Different prognosis of ARVC patients between DSG2 and PKP2 variant carriers

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy mainly caused by desmosomal gene variants. In Europe and North America, pathogenic variants in PKP2 were identified in most of the ARVC patients. On the other hand, we have reported that the genetic backgrounds of ARVC in Japanese were different from those in European; pathogenic variants in DSG2 were predominant in Japanese. Genotype-phenotype correlations, however, have not been clarified yet.

Purpose

In this study, we aimed to examine whether the genotype affect the phenotype and outcome in Japanese ARVC patients.

Methods and results

This study included 167 Japanese ARVC patients who received genetic testing (128 males [77%]). Their median age at diagnosis was 44 [24–55] years old and median follow-up duration was 10 [4–21] years. We found 90 patients with pathogenic variants: 52 in DSG2 (31%), 30 in PKP2 (18%), 3 in DSP (1.8%), 1 in DSC (0.6%), 1 in JUP (0.6%) and 3 in DES (1.8%). The age of the first sustained ventricular arrhythmia (SVT) were older in the patients with DSG2 than those with PKP2 variants (48±15 years vs. 35±15 years, P=0.008) but younger in DSG2 variant carriers at the first hospitalization for heart failure (41 [22–61] years vs. 67 [61–74] years, P=0.03). The left ventricular ejection fractions of DSG2 variant carriers were significantly lower at diagnosis than that of PKP2 (52 [41–60] % vs. 61 [56–66] %, P=0.002). Kaplan-Meier survival curve for lethal arrhythmic events including SVT, ventricular fibrillation and sudden death revealed that the event rate of DSG2 variant carriers was significantly lower than that of PKP2 (log-rank test, P=0.02) (Fig. 1).

Among 11 patients who had both SVT and hospitalizations for HF, 7 PKP2 variant carriers had SVT first, then, hospitalized for HF (48 [35–53] years and 67 [55–71] years, P=0.02). Contrary, the clinical course of 4 DSG2 variants carriers were different from those with PKP2 (54 [40–68] years for SVT and 65 [56–70, P=0.1] years for HF) (Fig. 2).

Conclusion

The patients with DSG2, which is the major causative gene for ARVC in Japanese, show different phenotype and outcome from those with PKP2. We should examine the effect of variants on the prognosis of ARVC patients in more large population including various ethnics.

Funding Acknowledgement

Type of funding sources: None.

Association Between Deleterious SCN5A Variants and Ventricular Septal Defect in Young Patients With Brugada Syndrome

OBJECTIVES

This study aimed to investigate the clinical characteristics of young patients with Brugada syndrome (BrS) with ventricular septal defect (VSD) and explore their genetic backgrounds.

BACKGROUND

VSD is the most frequently occurring congenital heart disease among children. In contrast, BrS is a rare hereditary disease that is responsible for ventricular fibrillation and sudden cardiac death. Owing to their low incidence, the genetic background and clinical characteristics of patients with BrS with VSD have not been elucidated yet.

METHODS

This study enrolled 36 individuals who were diagnosed with BrS when they were <20 years of age and performed genetic screening for SCN5A. The functional alteration in mutant Na⁺ channels was confirmed by patch clamp technique.

RESULTS

Among the 36 patients with BrS, 5 had been diagnosed with VSD. This study found 14 heterozygous SCN5A variants in 15 unrelated patients. The 5 patients with VSD carried SCN5A variants, including R367S, R535∗, R893C, W1345C, and G1743R. The 3 missense variants (R893C, W1345C, and G1743R) have been proved to reduce peak Na⁺ current to <10%. A functional analysis of SCN5A R367S was performed and the variant was found to be nonfunctional.

CONCLUSIONS

This study identified 5 loss-of-function SCN5A variants in 5 young patients with BrS with VSD. The study hypothesizes that altered blood flow in the right ventricular outflow tract leads to fibrosis and electrophysiological changes, predisposing the patients to earlier clinical presentation of BrS. In patients with VSD and ST-segment elevation in the right precordial leads, BrS should be considered and appropriate screening should be pursued accordingly.

Impact of cascade screening for catecholaminergic polymorphic ventricular tachycardia type 1

Objective

Human cardiac ryanodine receptor 2 (RYR2) shows autosomal-dominant inheritance in catecholaminergic polymorphic ventricular tachycardia type 1 (CPVT1); however, de novo variants have been observed in sporadic cases. Here, we investigated CPVT1-related RYR2 variant inheritance and its clinical significance between familial and de novo cases.

Methods

We enrolled 82 independent CPVT1 probands (median age: 10.0 (7.0–13.0) years; 45 male) carrying the RYR2 variants and whose biological origin could be confirmed by parental genetic analysis: assured familial inheritance (familial group: n=24) and de novo variants (de novo group: n=58). We examined the clinical characteristics of the probands and their family members carrying the RYR2 variants.

Results

In the de novo group, the RYR2 variants were more likely located in the C-terminus domain and less likely in the N-terminus domain than those in the familial group. The cumulative incidence of the first cardiac events (syncope and cardiac arrest (CA) or CA only) of the probands at the age of 5 and 10 years was higher in the de novo group than in the familial group. Nearly half of the probands in both groups experienced CA events before diagnosis. Only 37.5% of their genotype-positive parents had symptoms; however, at least 66.7% of the genotype-positive siblings were symptomatic.

Conclusions

CPVT1 probands harbouring de novo RYR2 variants showed an earlier onset of symptoms than those with assured familial inheritance. Cascade screening may enable early diagnosis, risk stratification and prophylactic therapeutic intervention to prevent sudden cardiac death of probands and potential genotype-positive family members.

Early onset of heart failure in Japanese ARVC patients with pathogenic desmosomal gene variants

Background

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy mainly caused by desmosomal gene variants. Although there are a lot of reports regarding to European ARVC patients, the ones in Asian are a few, and the characteristics of Asian ARVC have been still unclear. We have reported that the genetic backgrounds in Japanese ARVC patients were different from those in European ones. In this study, we aimed to examine the phenotype and outcome of Japanese ARVC patients with specific genetic backgrounds.

Methods and results

This study included 104 Japanese ARVC patients who were diagnosed as definite in the 2010 Task Force Criteria for ARVC and received genetic analysis (79 males [76%]; median age at diagnosis, 40 years [IQR 22–53 years].) Fifty-seven patients carried variants in desmosomal genes classified as pathogenic based on ACMG guideline: 30 in DSG2 (29%), 22 in PKP2 (21%), 2 in DSC2 (2%) and 3 in DSP (3%). The median age of diagnosis was significantly younger in the patients with the pathogenic variants than in those without (37 years [IQR 21–49 years] vs. 46 years [IQR 34–58 years], P=0.01). During a median follow-up of 9.3 years (IQR 3.5–20.9 years), 10 patients died and 2 were received heart transplantation. Sixty-two suffered lethal arrhythmic events including cardiopulmonary arrest, ventricular fibrillation, sustained ventricular tachycardia and appropriate shocks by implantable cardioverter defibrillator. Twenty-two were hospitalized for heart failure. There was no difference in these events rate between the two groups. However, survival analysis revealed that patients with pathogenic variants hospitalized for heart failure significantly earlier in their life than those without (P=0.04, log-rank test, Figure 1).

Conclusions

The Japanese ARVC patients with pathogenic variants in desmosomal genes are diagnosed and hospitalize for heart failure at younger age than those without. These findings have not been reported in other ethnics. Our study warns that we should be cautious for not only the prevention of lethal arrhythmic events but also the progress of the heart failure in Japanese ARVC patients with pathogenic variants.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Japan Agency for Medical Research and Development Figure 1

Clinical significance of controlling nutritional status score for predicting short-term clinical events in takotsubo syndrome: a multicenter study

Background

The Controlling Nutritional Status (CONUT) score is well known as a marker of nutritional status. Previous studies have reported that CONUT score could predict a prognosis of acute or chronic heart failure, and infective endocarditis. Takotsubo syndrome (TTS) is said to have a relatively good prognosis, but some patients have a bad turning point in hospital stay. Lower systolic blood pressure on admission, history of diabetes mellitus, and β-blocker use before admission have been reported as predictors of in-hospital cardiac complications. However, the prognostic utility of CONUT score in TTS is unclear. The aim of study was to evaluate duration of hospital stay and short-term clinical events with CONUT score in TTS.

Methods

Seventy-nine TTS patients who were admitted to 3 medical centers in Japan between January 2011 and October 2019 were enrolled. The average age was 71.8±11.5 years old, and the prevalence of female sex was 81%. The CONUT score was calculated based on the serum albumin, total lymphocyte and total cholesterol on admission. We retrospectively investigated the association between the short-term clinical events and CONUT score. The duration of hospital stay was defined as the primely outcome, and all cause death and congestive heart failure in hospital stay as the secondary outcome.

Results

The average CONUT score was 3.7±3.0. A positive correlation was found between the CONUT score and the duration of hospital stay (r=0.56, p&lt;0.01). Twenty (25.3%) patients suffered from clinical events (all cause death and congestive heart failure in hospital). Those patients with clinical events had significantly higher the CONUT score than those without (all cause death, 7.2±2.6 vs. 3.5±2.9, p&lt;0.01, congestive heart failure, 5.3±3.4 vs. 3.3±2.8, p=0.02, composite clinical events, 5.8±3.2 vs. 3.0±2.6, p&lt;0.01). ROC curve analysis revealed that the optimal cut-off value of the CONUT score for the prediction of composite clinical events was 4.0 (AUC: 0.75, sensitivity: 80%, Specificity: 64%). The patients with CONUT score of 4 or more (high COUNT score) were more prevalent in patients who experienced composite clinical events than in those who didn't (80% vs. 35.6%, p&lt;0.01). The patients with a high CONUT score had a longer hospital stay and higher occurrence of composite clinical events than those with CONUT score less than 4 (respectively, 27.2±19.1 days vs. 13.8±8.3 days, p&lt;0.01, 25.3% vs. 9.5%, p&lt;0.01).

Conclusions

The CONUT score in TTS patients was strongly associated with the duration of hospital stay and clinical events in hospital. The CONUT score is a simple indicator that can be calculated with only three factors. Therefore, the CONUT score on admission may be useful for a predictor of short-term clinical events in TTS patients.

Funding Acknowledgement

Type of funding source: None

Long-read sequence confirmed a large deletion of MYH6 and MYH7 in a family with atrial septal defect

Background

Genome structural variants (SVs) have larger effect on human genome functions than single nucleotide variants (SNVs). Although short-read sequencing (SRS) is current major next generation sequencing method and has given us a great benefit to elucidate the genetic background of inherited diseases, it does not detect SVs accurately. Long-read sequencing (LRS) produces tens to thousands of kilobases reads and detects the breakpoints of complex SVs. This study aimed to confirm a large deletion, which was suspected by SRS, using LRS by Oxford Nanopore technology (ONT).

Methods

Genomic libraries for SRS was prepared with HaloPlex. Targeted SRS was performed for 58 genes with MiSeq. Genomic libraries for LRS were prepared using the Ligation sequencing 1D kit SQK-LSK109 (ONT). Whole genome LRS was performed with GridION X5 and R9.4 flow cells (ONT).

Results

The patient was a five-month-old boy with atrial septal defect (ASD) and atrial tachycardia. Though SRS failed to identify any causative SNVs, the results with SureCall software (Agilent) suspected a deletion between exon 3 to exon 26 in MYH6 encoding α heavy chains of cardiac myosin. The variants in MYH6 are known to be associated with ASD. Because a deletion between MYH6 exon 26 and MYH7 exon 27 was reported as esv2748480 on the Database of Genomic Variants, we performed long-range PCR from MYH6 intron26 to MYH7 exon26 and found an abnormal 1.5K bases PCR product only in the case. Due to high homology of MYH6 and MYH7, Sanger sequencing failed to detect the break point.

In LRS, 3 flow cells generated 3.8M base-called reads containing 42G bases with N50 of 13K bases. We used NGMLR, which is a long-read mapper, to align the reads to the human reference genome (hg38). SVs were called by Sniffles detecting all types of SVs. The deletion was found to range from chr14: 23390037 to 23419824 (see figure) and did not contain other SVs. There was no pathogenic SV on ACTC1, GATA4, TBX20 and TLL1 which are genes related to ASD on Genetic Testing Registry.

His mother had also ASD and harbored the same deletion.

Conclusions

This is the first report to identify a large deletion between MYH6 and MYH7 in the family with ASD. The combination of SRS and LRS is useful to detect SVs in patients with suspected inherited diseases but carried no causative SNVs.

Funding Acknowledgement

Type of funding source: None

Splice site mutation of LMNA causes severe dilated cardiomyopathy via strong dominant reduction of total lamin expression

Objective

LMNA is a known causative gene of dilated cardiomyopathy (DCM) and familial cardiac conduction disturbance (CCD). Genetic variants affecting the pre-mRNA splicing process often lead to premature stop codons and result in nonsense-mediated mRNA decay (NMD), followed by degradation of mutated alleles. The misssense variant LMNA c. 936G&gt;C was previously reported in a French family affected by muscular dystrophy, CCD, and DCM, but no detailed analysis has been performed. We so far identified the same variant in two Japanese families affected by CCD and DCM. In this study, we investigated the molecular consequences of the variant located at the last codon of LMNA exon5 to demonstrate its pathogenicity.

Methods

Genomic DNA and total RNA were isolated from patients' peripheral blood lymphocytes or cardiac tissue. LMNA-coding exons were screened by direct sequencing. Complementary DNAs (cDNAs) were generated by reverse transcription PCR from RNA. Quantitative PCR (qPCR) was performed to quantify the LMNA cDNA amount by using specific primers for lamins A and C. The protein expressions of both isoforms were analyzed by western blotting.

Results

We detected the heterozygous LMNA c.936 G&gt;C (p. Q312H) variant at the end of exon 5 by genomic DNA sequencing in two unrelated Japanese families (figure. pedigree) affected by DCM and CCD. In a genomic database survey, we did not find the variant in either gnomAD, TogoVar, or the Human Genetic Variation Database. The two commonly used splice site predictor tools, NetGene2 and FSPLICE, estimated that this site was a splice donor site. Sequencing of cDNA demonstrated that the mutated allele was absent. By qPCR assay, we confirmed a 90% reduction in LMNA cDNA. Western blot analysis revealed that lamin A and C expression was reduced far more than 50% (figure. western blot).

Conclusions

We report a LMNA missense mutation found in two families, which disrupts a normal splicing site, leads to NMD, and resulted in severe cardiac laminopathy. The drastic reductions of lamin expression at the cDNA and protein levels suggested that other co-existing mechanisms may also have suppressed the expression of the healthy wild type allele.

Pedigree and western blot assay

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science KAKENHI

LMNA Missense Mutation Causes Nonsense-Mediated mRNA Decay and Severe Dilated Cardiomyopathy

BACKGROUND

LMNA is a known causative gene of dilated cardiomyopathy and familial conduction disturbance. Nonsense-mediated mRNA decay, normally caused by nonsense mutations, is a safeguard process to protect cells from deleterious effects of inappropriate proteins from mutated genes. Nonsense-mediated mRNA decay induced by nonstop codon mutations is rare. We investigated the effect of an LMNA missense mutation identified in 2 families affected by cardiac laminopathy.

METHODS

Genomic DNA and total RNA were isolated from patients' peripheral blood lymphocytes or cardiac tissue. LMNA-coding exons were screened by direct sequencing. Complementary DNAs were generated by a reverse transcription-polymerase chain reaction from total RNA. Quantitative polymerase chain reaction was performed to quantify the LMNA complementary DNA amount by using specific primers for lamins A and C. A minigene splicing reporter experiment was performed to assess the effect of detected variants on RNA splicing. The protein expressions of both isoforms were analyzed by Western blotting.

RESULTS

We detected a missense variant c.936 G>C (p. Q312H) at the end of exon 5 of LMNA by genomic DNA sequencing in 2 unrelated families affected by dilated cardiomyopathy and cardiac conduction disturbance. This variant was previously reported in a French family suffering from muscular dystrophy and cardiac conduction disturbance. Sequencing of complementary DNA demonstrated that the mutated allele was absent. By quantitative polymerase chain reaction assay, we confirmed a 90% reduction in LMNA complementary DNA. The minigene splicing reporter assay demonstrated a splicing error by the variant. Western blot analysis revealed that lamin A and C expressions were reduced far >50%.

CONCLUSIONS

We report an LMNA missense mutation found in 2 families, which disrupted a normal splicing site, led to nonsense-mediated mRNA decay, and resulted in severe cardiac laminopathy.

Prevention of postprandial hypotension-related syncope by caffeine in a patient with long-standing diabetes mellitus

A 74-year-old man who had type 2 diabetes mellitus of a duration of 20 years was admitted for syncope after eating a high carbohydrate meal. Although he had had episodes of pallor or syncope after carbohydrate-rich meals, such as with large amounts of white rice, several times within a year and he had been taken to hospitals emergently, the etiology of these episodes had remained unclear despite his undergoing several studies. Studies did show severe orthostatic hypotension during the head-up tilt test and a decrease in the coefficient of variation of the R-R interval (CVR-R) on resting electrocardiogram, suggesting severe autonomic nervous dysfunction. Because of the episodes of syncope after eating a carbohydrate-rich meal, we investigated whether he had postprandial hypotension (PPH). The 75 g oral glucose tolerance test revealed a significant decrease in his postprandial blood pressure by about 40 mmHg, leading to the diagnosis of PPH. The carbohydrate-rich meal test induced syncope with systolic blood pressure under 40 mmHg. Then 150 mg caffeine was administered before a second carbohydrate-rich meal. The marked decline in postprandial blood pressure was suppressed and plasma noradrenaline levels were gradually increased over a period of 60 minutes. Caffeine could be useful for prevention of postprandial hypotension-related syncope.

P176 Left ventricular diastolic function by gated myocardial perfusion SPECT strongly reflects NT-ProBNP

Background

The importance of left ventricle diastolic dysfunction (LVDD) has been recognized widely, as it is well established that heart failure with preserved ejection fraction has a poor prognosis. Furthermore, N-terminal pro–B-type natriuretic peptide (NT-ProBNP) is used as a marker of heart failure. However, the association between LVDD and NT-proBNP is unclear. 

Purpose

The aim of this study was to clarify the association between LVDD and NT-ProBNP. 

Methods

In this study, an index based on gated myocardial perfusion SPECT using CardioREPO software for the diagnosis of LVDD was used. Out of the 171 patients who underwent myocardial perfusion imaging (MPI) between January 2015 and December 2018, 163 individuals (116 men and 47 women) completed MPI and NT-ProBNP. Patients were classified into 4 groups: NT-ProBNP levels below 125 pg/ml (n = 52), NT-ProBNP levels 125 to 400 pg/ml (n = 33), NT-ProBNP levels 400 to 900 pg/ml (n = 23), and NT-ProBNP levels over 900 pg/ml (n = 37). CardioREPO parameters (peak filling rate　(PFR), 1/3 mean filling rate (MFR), and time to peak filling rate/R-R (TTPFR)) were compared between the 4 NT-ProBNP groups. 

Results

Of the 163 patients, 55 had LVDD. The PFR and 1/3MFR were associated with LVDD. There was a statistically significant difference in PFR and 1/3 MFR between the NT-ProBNP levels below 125 pg/ml group and the NT-ProBNP levels 400 to 900 pg/ml group (PFR = 2.51+/-1.11 vs. 1.80+/-0.65, p = 0.001; 1/3 MFR = 1.41+/-0.55 vs. 1.06+/-0.47, p = 0.006, Table).

Conclusions

The MPI indices obtained by CardioREPO software were useful in the diagnosis of LVDD. The evaluation of LVDD by MPI correlated with NT-Pro BNP level is thought to have a clinical utility in the diagnosis and management of LVDD.

Variable: NT-ProBNP 　 0-125 (n = 52) 125-400 (n = 33) 400-900 (n = 23) 900- (n = 37) p Age 66 ± 11 72 ± 11 68 ± 17 70 ± 12 0.133 Male 40 (77%) 22 (12%) 18 (78%) 23 (62%) 0.36 Left ventricular diastolic dysfunction 8 (15%) 4 (12%) 10 (43%) 27 (73%) &lt;0.001 E/A 0.9 ± 0.3 0.8 ± 0.2 1.1 ± 0.7 1.4 ± 0.9 (35) &lt;0.001 E/e" 10.27 ± 3.69 (20) 8.83 ± 3.56 (10) 12.46 ± 3.75 (12) 20.25 ± 8.30 (25) &lt;0.001 rest-PFR /s 2.51 ± 1.11 2.06 ± 0.58 2.16 ± 0.65 1.80 ± 0.65 0.001 rest-1/3 MFR /s 1.41 ± 0.55 1.19 ± 0.41 1.16 ± 0.50 1.06 ±0.47 0.008 rest-TTPFR ms 177 ± 53 181 ± 69 198 ± 80 166 ± 85 0.38 rest-TTPFR / R-R 　 0.19 ± 0.06 0.20 ± 0.11 0.21 ±0.09 0.21 ± 0.15 0.92

Genetic variants of alcohol-metabolizing enzymes in Brugada syndrome: Insights into syncope after drinking alcohol

BACKGROUND

Patients with Brugada syndrome (BrS) are known to have arrhythmic events after alcohol drinking and are recommended to avoid its excessive intake. Mechanisms underlying the alcohol-induced cardiac events are however unknown. This study aimed to test the hypothesis whether activity of alcohol-metabolizing enzymes determines fatal arrhythmic events after drinking alcohol.

METHODS

A total of 198 Japanese patients with BrS were enrolled in this study. These patients were classified into symptomatic (n = 90) and asymptomatic (n = 108) groups. The former was divided into an alcohol-related group (syncope after alcohol drinking, n = 16) and an alcohol-unrelated group (n = 74). Polymerase chain reaction was performed to determine genetic variants of genes encoding alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2).

RESULTS

The genotype distribution for ALDH2 was not significantly different between symptomatic and asymptomatic groups and between alcohol-related and alcohol-unrelated groups. The genotype distribution for ADH1B was not significantly different between symptomatic and asymptomatic groups, but the genotype ADH1B His/His was significantly more prevalent in the alcohol-related group than in the alcohol-unrelated group (81.3% vs 50%, P = .023). In multivariate logistic regression analysis, the genotype of ADH1B His/His was independently associated with syncope after alcohol drinking (odds ratio, 5.746; 95% confidence interval, 1.580-28.421; P = .007).

CONCLUSIONS

Arrhythmic events after alcohol drinking was associated with enhanced activity of alcohol-metabolizing enzyme ADH1B in our cohort of BrS. Therefore, the lifestyle change to avoid the excessive alcohol intake deserves attention.

Sex-Dependent Phenotypic Variability of an SCN5A Mutation: Brugada Syndrome and Sick Sinus Syndrome

Background Brugada syndrome ( BS ) is known to be 9 times more prevalent in males than females. However, little is known about the development of sick sinus syndrome in female members with familial BS . Methods and Results Familial BS patients and family members, both from our institutions and collaborating sites that specialize in clinical care of BS , participated in this study. We collected information on their clinical and genetic background, along with the inheritance patterns of BS . Detailed information on each case with familial BS is described. A total of 7 families, including 25 BS patients (12 females and 13 males), were included. Seven were probands and 18 were family members. Ten out of the 12 female patients and none of the 13 male patients developed sick sinus syndrome. Sudden death or spontaneous ventricular fibrillation occurred in 7 out of 13 male patients and 2 out of 12 female patients. Conclusions Familial BS existed in which female patients developed sick sinus syndrome but male patients did not. Some of those female patients with sick sinus syndrome had unrecognized BS . Information should be collected not only regarding a family history of sudden death or BS , but also whether a pacemaker was implanted in female members.

Copy number variations of SCN5A in Brugada syndrome

BACKGROUND

Loss-of-function mutations in SCN5A are associated in ∼20% of Brugada syndrome (BrS) patients. Copy number variations (CNVs) have been shown to be associated with several inherited arrhythmia syndromes.

OBJECTIVE

The purpose of this study was to investigate SCN5A CNVs among BrS probands.

METHODS

The study cohort consisted of 151 BrS probands who were symptomatic or had a family history of BrS, sudden death, syncope, or arrhythmic diseases. We performed sequence analysis of SCN5A by the Sanger method. For detecting CNVs in SCN5A, we performed multiplex ligation-dependent probe amplification analysis of the 151 BrS probands.

RESULTS

We identified pathogenic SCN5A mutations in 20 probands by the Sanger method. In 140 probands in whom multiplex ligation-dependent probe amplification was successfully performed, 4 probands were found to present different CNVs (deletion in 3 and duplication in 1). Three of them had fatal arrhythmia events; the remaining 1 was asymptomatic but had a family history. Mean age at diagnosis was 23 ± 14 years. All of the baseline 12-lead electrocardiograms showed PQ-interval prolongation. The characteristics of these 4 probands with CNVs were similar to those of the probands with mutations leading to premature truncation of the protein or missense mutations causing peak I_Na reduction >90%.

CONCLUSION

We identified SCN5A CNVs in 2.9% of BrS probands who were symptomatic or had a family history.

Effects of intertrochanteric osteotomy plane and preoperative femoral anteversion on the postoperative morphology of the proximal femur in transtrochanteric anterior rotational osteotomy: 3D CT-based simulation study

BACKGROUND

Transtrochanteric anterior rotational osteotomy (ARO) is joint-preserving surgery for patients with osteonecrosis of the femoral head (ONFH). During ARO, femoral neck-shaft varus angulation by changing intertrochanteric osteotomy plane is often designed to obtain a sufficient postoperative intact ratio. However, the effect of intertrochanteric osteotomy plane on postoperative femoral anteversion has not been well examined. Therefore, we performed a simulation study of ARO to determine how intertrochanteric osteotomy plane and preoperative femoral anteversion affect both femoral neck-shaft varus angle and postoperative femoral anteversion.

HYPOTHESIS

Both femoral neck-shaft varus angle and postoperative femoral anteversion are predicted by intertrochanteric osteotomy plane and preoperative femoral anteversion in ARO.

MATERIALS AND METHODS

Using CT-data obtained from 10 hips in 10 patients with ONFH, ARO was simulated. On anteroposterior view, basic intertrochanteric osteotomy line (AP-view line) was defined as the perpendicular line to the femoral neck axis. On lateral view, basic intertrochanteric osteotomy line (lateral-view line) made through the cut surface of greater trochanter was defined as the perpendicular line to the lateral axis of the femur. By changing either AP-view or lateral-view line, 49 ARO models/hip were produced, in which femoral neck-shaft varus angle and postoperative femoral anteversion were assessed.

RESULTS

With increase in the vertically-inclined degree of AP-view line, both neck-shaft varus angle and postoperative femoral anteversion increased. With increase in the posteriorly-tilted degree of lateral-view line, neck-shaft varus angle increased, whereas postoperative femoral anteversion decreased. The approximation equations based on the multiple regression analyses were as follows: neck-shaft varus angle≈vertically-inclined degree of AP-view line×0.9+posteriorly-tilted degree of lateral-view line×0.8+preoperative femoral anteversion×0.7; postoperative femoral anteversion≈vertically-inclined degree of AP-view line×1.1-posteriorly-tilted degree of lateral-view line×0.8.

DISCUSSION

The postoperative morphology of proximal femur was nearly defined by intertrochanteric osteotomy plane with preoperative femoral anteversion, which is useful for preoperative planning in terms of both achieving a sufficient postoperative intact ratio and maintaining femoral anteversion.

LEVEL OF EVIDENCE

Level IV case series without control group.

Quantitative analysis of PKP2 and neighbouring genes in a patient with arrhythmogenic right ventricular cardiomyopathy caused by heterozygous PKP2 deletion

AIMS

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disease mainly caused by desmosome gene mutations. The genetic culprit, however, remains elusive in ∼50% of ARVC patients. One of the reasons for missing genetic abnormalities is the difficulty in detecting large deletions/duplications, which are called as copy number variation (CNV) by the Sanger sequencing method. This study aimed to identify CNVs in PKP2 and a part of other desmosome genes in ARVC patients.

METHODS AND RESULTS

The study cohort consisted of 71 ARVC probands who were diagnosed as definite or borderline cases based on 2010 Task Force Criteria. Among them, 32 (45%) carried at least one mutation in desmosome genes detected by the Sanger method. Using the multiplex ligation-dependent probe amplification method, we identified a male proband (1.4%) with a complete deletion of all PKP2 coding exons. He was 31 years old and showed exercise-induced sustained ventricular tachycardia with superior axis and left bundle-branch block pattern. His cardiac magnetic resonance imaging and computed tomography showed right ventricular dilatation and reduced ejection fraction. His 12-lead electrocardiogram showed T-wave inversion in V1-V3, and late potentials were positive, indicating definite ARVC. To confirm the precise location of the deletion, we performed relative quantitative PCR. We found complete deletion of both SYT10 and ALG10 located in 3' of PKP2; the total deletion size was at least 1.23 Mb.

CONCLUSION

Screening for CNVs in desmosome genes is useful to identify the genetic basis of disease in clinically suspected ARVC patients.

Factors influencing progressive collapse of the transposed necrotic lesion after transtrochanteric anterior rotational osteotomy for osteonecrosis of the femoral head

BACKGROUND

Transtrochanteric anterior rotational osteotomy (ARO) for osteonecrosis of the femoral head (ONFH) can preserve for a long-time collapsed femoral head. Progressive collapse of anteriorly-transposed necrotic lesion leads to secondary arthritic changes and clinical failure. Critical factors influencing collapse of the transposed necrotic lesion after ARO remain largely unknown. Therefore, we performed a retrospective study of ARO to determine: (1) if preoperative collapse influences collapse of the transposed necrotic area, (2) if any other factor may influence collapse of the transposed necrotic area.

HYPOTHESIS

We hypothesized the degree of preoperative femoral head collapse influences progressive collapse of the transposed necrotic lesion after ARO.

MATERIALS AND METHODS

We reviewed 47 hips in 42 patients with ONFH treated with ARO between 2000 and 2005 with a mean follow-up of 11.4 years (10-14 years). The occurrence of progressive collapse of the transposed necrotic lesion after ARO was examined using lateral radiographs taken at least once every year after ARO. The following factors were statistically analyzed: age, sex, body mass index, Harris Hip Score (HHS), preoperative level of collapse, extent of the necrotic lesion and postoperative intact ratio (ratio of the transposed intact articular surface of the femoral head).

RESULTS

Progressive collapse of the transposed necrotic lesion (progressive collapse group) was seen in 17 hips (36%) during a mean period of 1.8 years (0.5-3.7 years) after ARO, which has developed within 4 years in all cases. Preoperative level of collapse in the progressive collapse group (4.4±1.4mm) was significantly larger than that in the non-progressive collapse group (2.1±1.0mm), which was independently associated with progressive collapse of the transposed necrotic lesion in multivariate analysis (P<0.0001) with cut off point of 2.98mm. In univariate analysis, lower preoperative HHS, severe extent of the necrotic lesion and the lower postoperative intact ratio were also associated with progressive collapse of the transposed necrotic lesion, but were not associated as independent factors in multivariate analysis.

DISCUSSION

The current study suggests that progressive collapse of the transposed necrotic lesion after ARO depends mainly on the preoperative level of collapse (cut-off point=2.98mm).

LEVEL OF EVIDENCE

IV; retrospective case series.

Phenotypic Variability of ANK2 Mutations in Patients With Inherited Primary Arrhythmia Syndromes

BACKGROUND

Mutations inANK2have been reported to cause various arrhythmia phenotypes. The prevalence ofANK2mutation carriers in inherited primary arrhythmia syndrome (IPAS), however, remains unknown in Japanese. Using a next-generation sequencer, we aimed to identifyANK2mutations in our cohort of IPAS patients, in whom conventional Sanger sequencing failed to identify pathogenic mutations in major causative genes, and to assess the clinical characteristics ofANK2mutation carriers.Methods and Results:We screened 535 probands with IPAS and analyzed 46 genes including wholeANK2exons using a bench-top NGS (MiSeq, Illumina) or performed whole-exome-sequencing using HiSeq2000 (Illumina). As a result, 12 of 535 probands (2.2%, aged 0-61 years, 5 males) were found to carry 7 different heterozygousANK2mutations.ANK2-W1535R was identified in 5 LQTS patients and 1 symptomatic BrS and was predicted as damaging by multiple prediction software. In total, as to phenotype, there were 8 LQTS, 2 BrS, 1 IVF, and 1 SSS/AF. Surprisingly, 4/8 LQTS patients had the acquired type of LQTS (aLQTS) and suffered torsades de pointes. A total of 7 of 12 patients had documented malignant ventricular tachyarrhythmias.

CONCLUSIONS

VariousANK2mutations are associated with a wide range of phenotypes, including aLQTS, especially with ventricular fibrillation, representing "ankyrin-B" syndrome. (Circ J 2016; 80: 2435-2442).

A type 2 ryanodine receptor variant associated with reduced Ca2+ release and short-coupled torsades de pointes ventricular arrhythmia

BACKGROUND

Ventricular fibrillation may be caused by premature ventricular contractions (PVCs) whose coupling intervals are <300 ms, a characteristic of the short-coupled variant of torsades de pointes (scTdP).

OBJECTIVE

The purpose of this study was to analyze the underlying cardiac ryanodine receptor (RyR2) variants in patients with scTdP.

METHODS

Seven patients with scTdP (mean age 34 ± 12 years; 4 men and 3 women) were enrolled in this study. The RyR2 gene was screened by targeted gene sequencing methods; variant minor allele frequency was confirmed in 3 databases; and the pathogenicity was investigated in silico analysis using multiple tools. The activity of wild-type and mutant RyR2 channels was evaluated by monitoring Ca²⁺ signals of HEK293 cells with a [³H]ryanodine binding assay.

RESULTS

The mean coupling interval of PVCs was 282 ± 13 ms. The 12-lead electrocardiogram had no specific findings except PVCs with an extremely short-coupling interval. Genetic analysis revealed 3 novel RyR2 variants and 1 polymorphism, all located in the cytoplasmic region. p.Ser4938Phe was not detected in 3 databases, and in silico analysis indicated its pathogenicity. In functional analysis, p.Ser4938Phe demonstrated loss of function and impaired RyR2 channel Ca²⁺ release, while 2 other variants, p.Val1024Ile and p.Ala2673Val, had mild gain-of-function effects but were similar to the polymorphism p.Asn1551Ser.

CONCLUSION

We identified an RyR2 variant associated with reduced Ca²⁺ release and short-coupled torsades de pointes ventricular arrhythmia. The mechanisms of arrhythmogenesis remain unclear.

Multigenerational Inheritance of Long QT Syndrome Type 2 in a Japanese Family

Congenital long QT syndrome (LQTS) is an important cause of sudden cardiac death in young people without any other structural disease. Mutations in the genes encoding the cardiac ion channels or associated proteins have been shown to result in ion channel dysfunction and thereby causing LQTS. We investigated a Japanese family with LQTS for four generations, with the female family members showing severe symptoms. We performed genetic tests for LQTS-related genes and identified a heterozygous KCNH2 mutation (p.K638del). In the family, the KCNH2 mutation had a very high multigenerational inheritance, and female genotype positives showed more severe phenotypes.

High Frequency of Early Repolarization and Brugada-Type Electrocardiograms in Hypercalcemia

BACKGROUND

J wave, or early repolarization has recently been associated with an increased risk of lethal arrhythmia and sudden death, both in idiopathic ventricular fibrillation and in the general population. Hypercalcemia is one of the causes of J point and ST segment elevation, but the relationship has not been well studied. The aim of this study was to examine the effects of hypercalcemia on J point elevation.

METHODS

Electrocardiographic findings were compared in 89 patients with hypercalcemia and 267 age- and sex-matched healthy controls with normocalcemia. The association of J point elevation with arrhythmia events in patients with hypercalcemia was also studied.

RESULTS

The PR interval and the QRS duration were longer in patients with hypercalcemia than in normocalcemic controls. Both the QT and the corrected QT intervals were shorter in patients with hypercalcemia compared with normocalcemic controls. Conduction disorders, ST-T abnormalities, and J point elevation were more common in patients with hypercalcemia than normocalcemic controls. Following the resolution of hypercalcemia, the frequency of J point elevation decreased to a level similar to that noted in controls. During hospitalization, no arrhythmia event occurred in patients with hypercalcemia.

CONCLUSION

Hypercalcemia was associated with J point elevation.

Frequency characteristics and associations with the defibrillation threshold of ventricular fibrillation in patients with implantable cardioverter defibrillators

OBJECTIVE

The dominant frequency (DF) in frequency analyses is considered to represent the objective cycle length and complexity of activation under conditions of ventricular fibrillation (VF). However, knowledge regarding the mechanisms determining the DF in human VF is limited. We studied the characteristics of the DF of human VF and relationship between DF and the defibrillation threshold.

METHODS

Seventy-two implantable cardioverter-defibrillator patients and 211 VF were studied. Using defibrillation tests, we performed a frequency analysis with fast Fourier transformation. The correlations between DF and clinical characteristics, including the defibrillation threshold, were assessed.

RESULTS

The mean DF of all induced VFs was 5.2±0.8 Hz. The patients were divided into two groups according to DF: the low-DF (DF <5.2 Hz, n=32) and high-DF (DF ≥5.2 Hz, n=40) groups. The frequency of structural heart disease was significantly higher in the low-DF group. In addition, the QRS duration, QT interval and effective refractory period of the right ventricle (RV-ERP) were significantly longer in the low-DF group. A multivariate analysis showed RV-ERP to be the only independent predictor of DF. Excluding patients receiving group III anti-arrhythmic drugs, which are known to have potent defibrillation threshold effects, the defibrillation threshold was significantly lower in the low-DF group (p=0.026).

CONCLUSION

We found that the DF of human VF is associated with underlying heart disease, the cardiac function, cardiac conduction, ventricular refractoriness and defibrillation threshold. Our findings may be useful for identifying and managing patients with a high defibrillation threshold.

Correlation between reduced p21(WAF1/CIP1) expression and abnormal p53 expression in esophageal carcinomas

p21(WAF1/CIP1) is a potent inhibitor of various cyclin-dependent kinases, the expression of which is transcriptionally regulated by tumor suppressor gene product p53. We immunohistochemically examined the expression of p53 and p21(WAF1/CIP1) in 61 esophageal squamous cell carcinomas. p53 protein was expressed in 37 (61%) of 61 carcinomas. p21(WAF1/CIP1) was consistently expressed in the normal stratified esophageal mucosa. In the carcinomas, the expression of p21(WAF1/CIP1) protein was markedly reduced or not expressed in 33 (54%) cases. Clinicopathologic analyses revealed that no significant correlation exists either between p53-positive and -negative cases or between p21(WAF1)/(CIP1)-positive and -negative cases. Twenty-four cases were p53-positive/p21(WAF1/CIP1) negative, 15 were p53-negative/p21(WAF1/CIP1)-positive, 13 were positive for both and 9 were negative for both, and these findings thus showed an inverse correlation of the positivity between p53 and p21(WAF1/CIP1) (p<0.05). Furthermore, of the 13 cases with positive staining for both, the distribution of the expression was mutually exclusive in 6 cases and coincidental in the remaining 7 cases. These findings showed the p53-dependent expression of p21(WAF1/CIP1) was observed in esophageal squamous cell carcinomas, while the lack of an absolute correlation between abnormal p53 expression and p21(WAF1/CIP1) expression suggested that the p53-independent expression of p21(WAF1/CIP1) might also occur in some portions of the esophageal squamous carcinomas, suggesting that the molecular mechanisms of esophageal carcinogenesis appear to be complicated.

Mechanical alternans in human idiopathic dilated cardiomyopathy is caused with impaired force-frequency relationship and enhanced poststimulation potentiation

Mechanical alternans (MA) is frequently observed in patients with heart failure, and is a predictor of cardiac events. However, there have been controversies regarding the conditions and mechanisms of MA. To clarify heart rate-dependent contractile properties related to MA, we performed incremental right atrial pacing in 17 idiopathic dilated cardiomyopathy (DCM) patients and in six control patients. The maximal increase in left ventricular dP/dt during pacing-induced tachycardia was assessed as the force gain in the force-frequency relationship (FG-FFR), and the maximal increase in left ventricular dP/dt of the first post-pacing beats was examined as the force gain in poststimulation potentiation (FG-PSP). As a result, MA was induced in 9 DCM patients (DCM MA(+)) but not in the other 8 DCM patients (DCM MA(-)), and not in any of the control patients. DCM MA(+) had significantly lower FG-FFR (34.7 ± 40.9 vs 159.4 ± 103.9 mmHg/s, P = 0.0091) and higher FG-PSP (500.0 ± 96.8 vs 321.9 ± 94.9 mmHg/s, P = 0.0017), and accordingly a wider gap between FG-PSP and FG-FFR (465.3 ± 119.4 vs 162.5 ± 123.6 mmHg/s, P = 0.0001) than DCM MA(-) patients. These characteristics of DCM MA(+) showed clear contrasts to those of the control patients. In conclusion, MA is caused with an impaired force-frequency relationship despite significant poststimulation potentiation, suggesting that MA reflects ineffective utilization of the potentiated intrinsic force during tachycardia.

Novel therapeutic strategies to target RCAS1, which induces apoptosis via ectodomain shedding

The expression of receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is associated with aggressive characteristics and poor overall survival for 15 different human malignancies. The correlation between RCAS1 expression and several clinicopathological variables, including tumor size, clinical stage, invasion depth and lymph node metastasis highlights this molecule's clinical significance. RCAS1 is a biomarker because: (1) its concentration in serum or pleural effusion is significantly higher in cancer patients; (2) its level is associated with treatment response; and (3) high RCAS1-valued serum from cancer patients inhibits growth of RCAS1 putative receptor-expressing K562 cells. RCAS1 is secreted by ectodomain shedding and induces apoptosis in peripheral lymphocytes and natural killer (NK) cells. Although its putative receptor and mechanism of apoptosis induction remain undefined, RCAS1 is believed to help tumor cells evade immune surveillance. RCAS1 expression is also related to changes in extracellular matrix characteristics, reduction of vimentin-positive stromal cells, and increased microvessel density (MVD), all suggesting that RCAS1 may induce connective tissue remodeling. Further exploration of RCAS1 biological function will facilitate development of novel therapeutic strategies that target RCAS1.

Benign premature ventricular complexes from the right ventricular outflow tract triggered polymorphic ventricular tachycardia in a latent type 2 LQTS patient

A 57-year-old woman showed frequent premature ventricular complexes (PVCs) originating from the right ventricular outflow tract (RVOT), and some of the PVCs triggered polymorphic ventricular tachycardia (PVT). Structural heart diseases were ruled out by conventional cardiac examinations. Radiofrequency catheter ablation was successful in eliminating the PVCs and subsequent PVT. However, epinephrine infusion unmasked her prolonged QT interval, and a genetic analysis revealed a KCNH2 mutation (R694H) as the cause of latent type-2 long QT syndrome (LQTS). This case suggests that latent LQTS may work as an arrhythmogenic substrate of PVT triggered by a benign form of RVOT-PVCs in patients with a structurally normal heart.

An appropriate defibrillation threshold obtained by the combined connection between two shock leads and ICD generator

A 60-year-old man with arrhythmogenic right ventricular cardiomyopathy was readmitted for the battery exchange of his implantable cardioverter-defibrillator (ICD). Since (i) he had been treated with a dual-coil shock lead (Sprint Fidelis, Medtronic) and (ii) pre-operative venography showed mild collateral flow to the left subclavian vein, a single-coil lead was additionally implanted. However, the single-coil defibrillation system was unable to terminate the induced ventricular fibrillation (VF), thus dual defibrillation shock pathways were created using the connection to the superior vena cava coil of the Fidelis lead. The combined connections of the two shock leads provided an appropriate margin of the defibrillation threshold.

Purification and Some Properties of an Extracellular Amylase from a Moderate Halophile, Micrococcus halobius

A moderate halophile, Micrococcus halobius ATCC 21727, produced an extracellular dextrinogenic amylase when cultivated in media containing 1 to 3 M NaCl. The amylase was purified from the culture filtrate to an electrophoretically homogenous state by glycogen-complex formation, diethylaminoethyl-cellulose chromatography, and Bio-Gel P-200 gel filtration. The enzyme had maximal activity at pH 6 to 7 in 0.25 M NaCl or 0.75 M KCl at 50 to 55 degrees C. The activity was lost by dialysis against distilled water. Molecular weight was estimated to be 89,000 by sodium dodecyl sulfate-gel electrophoresis. The action pattern on amylose, soluble starch, and glycogen showed that the products were maltose, maltotriose, and maltotetraose, with lesser amount of glucose.

Clinical significance of heparin-binding epidermal growth factor-like growth factor in peritoneal fluid of ovarian cancer

Epidermal growth factor receptor (EGFR) has been implicated in tumour growth and extension of ovarian cancer. Peritoneal fluid in ovarian cancer patients contains various growth factors that can promote tumour growth and extension. In order to investigate the clinical significance of EGFR ligands as activating factors of ovarian cancer, we examined the cell proliferation-promoting activity and the level of EGFR ligands in peritoneal fluid obtained from 99 patients. Proliferation-promoting activity in peritoneal fluid from 63 ovarian cancer patients (OVCA) was much higher than peritoneal fluid from 18 ovarian cyst patients (OVC) and 18 normal ovary patients (NO), and the activity was suppressed only by antibodies against EGFR or heparin-binding epidermal growth factor (HB-EGF). A large difference was observed in the level of EGFR ligands between HB-EGF and TGF-α or amphiregulin. The concentration of HB-EGF in OVCA significantly increased compared to that in OVC or NO (P<0.01). No significant difference in the concentration of TGF-α and amphiregulin was found between the OVCA and NO or OVC groups. In peritoneal fluid, HB-EGF is sufficiently elevated to activate cancer cells even at an early stage of OVCA. These results suggested that HB-EGF in peritoneal fluid might play a key role in cell survival and in the proliferation of OVCA.

Laparoscopically assisted distal gastrectomy for early gastric cancer in the elderly

Background

Open gastrectomy is associated with increased morbidity and a longer hospital stay than laparoscopically assisted gastrectomy. The aim of this study was to clarify the value of laparoscopically assisted distal gastrectomy (LDG) in the elderly, in whom co-morbid disease is generally more common.

Methods

Forty-five elderly patients (aged 70 years or more) and 57 younger patients who underwent LDG, and 28 elderly patients who underwent open distal gastrectomy (ODG) for early gastric cancer between January 1994 and April 2003 were studied. Demographics and postoperative outcomes were compared.

Results

Co-morbidity was more common in elderly patients than in younger patients who underwent LDG (25 of 45 versus 16 of 57; P = 0·004). The postoperative complication rate, time to solid diet and postoperative hospital stay were similar in these two groups. Elderly patients who underwent LDG had a significantly reduced medical complication rate (two of 45 versus six of 28; P = 0·023), time to first flatus (3·7 versus 4·2 days; P = 0·042), time to solid diet (4·6 versus 5·5 days; P = 0·011) and postoperative hospital stay (16·3 versus 23·9 days; P = 0·011) than elderly patients who had ODG.

Conclusion

LDG offers particular advantages to elderly patients with early gastric cancer, including rapid return of gastrointestinal function, fewer complications and a shorter hospital stay.

T lymphocyte subsets and Th1/Th2 balance after laparoscopy-assisted distal gastrectomy

BACKGROUND

Laparoscopic surgery provides for a less invasive procedure than open surgery in patients with gastric cancer, but the immune responses after laparoscopic surgery for early gastric cancer remain unknown.

METHODS

Peripheral blood mononuclear cells from 20 patients with early gastric cancer who underwent laparoscopy-assisted distal gastrectomy (LADG) or open distal gastrectomy (ODG) were obtained; the cell surface molecules and intracellular cytokines (IFN-gamma and IL-4) were measured by flow cytometry.

RESULTS

The populations of T lymphocytes after LADG, including CD3-, 4-, 8-, 57-, and HLA-DR-positive lymphocytes, showed patterns similar to those after ODG. The production of IFN-gamma as Th1 cell function decreased significantly on the third postoperative day after ODG but increased after LADG. The production of IL-4, representing Th2 cell function, increased postoperatively after ODG but not after LADG.

CONCLUSIONS

When compared with ODG, LADG contributes to the preservation of postsurgical Th1 cell-mediated immune function.

Association between RCAS1 expression and clinical outcome in uterine endometrial cancer

RCAS1, which acts as a ligand for a putative receptor on immune cells such as peripheral lymphocytes and natural killer cells, is strongly expressed in human cancers. RCAS1 can induce these cells to undergo apoptotic cell death, which suggests that RCAS1 expression may prohibit the stromal reaction occurring in a tumour. To clarify the clinical significance of RCAS1 expression in uterine endometrial cancer, we analysed the association between RCAS1 expression and clinicopathologic variables by statistical methods. With the use of immunohistochemical techniques, we performed a retrospective study of RCAS1 expression in resected tumour tissue from 147 patients with uterine endometrial cancer. We evaluated the statistical correlation between RCAS1 expression and clinicopathologic variables. RCAS1 was expressed in 106 of 147 patients with uterine endometrial cancer; 30 of these 147 patients showed RCAS1 overexpression. Overexpression of RCAS1 was significantly correlated with age at surgery, stage, extent of myometrial invasion, and positive peritoneal cytologic results. Multivariate analysis revealed that RCAS1 expression and metastasis were clinically significant prognostic factors for the overall survival. These findings indicated that analysis for RCAS1 expression can provide crucial information about the clinical behaviour of uterine endometrial cancer, which may be valuable for the management of patients with this disease.

Acute rejection of orthotopic corneal xenografts in mice depends on CD4(+) T cells and self-antigen-presenting cells

PURPOSE

Guinea pig corneal xenografts have been reported to be rejected acutely in eyes of normal adult mice. Rejection of this type is independent of xenoreactive antibodies, and mice deficient in CD8(+) and NK T cells are unable to reject guinea pig corneal grafts acutely. Therefore, a study was conducted to determine the extent and manner by which CD4(+) T cells are responsible for rejection of orthotopic corneal xenografts.

METHODS

Xenogeneic corneas were prepared from eyes of normal guinea pigs and grafted orthotopically into normal eyes of C57BL/6 mice, class II major histocompatibility complex (MHC) knockout (KO) mice, and class II MHC KO mice reconstituted with syngeneic (C57BL/6) CD4(+) T cells and/or bone marrow cells. Graft survival was assessed clinically, and success of cellular reconstitution was assayed using flow cytometric analysis of peripheral blood leukocytes. T cells from rejector mice were analyzed for proliferative responses to guinea pig xenoantigens in vitro.

RESULTS

Median survival times (MST) of corneal xenografts in MHC class II KO mice was significantly delayed (31 days) compared with grafts in wild-type C57BL/6 eyes (9 days). Acute rejection was restored almost completely when MHC class II KO mice were reconstituted simultaneously with C57BL/6 bone marrow and CD4(+) T cells, but not when the KO mice were reconstituted with either CD4(+) T cells or bone marrow cells alone. Mice that rejected guinea pig corneas possessed only CD4(+) T cells capable of responding to guinea pig xenoantigens in vitro.

CONCLUSIONS

Acute rejection of orthotopic corneal xenografts in mice is mediated by CD4(+) T cells that detect guinea pig xenoantigens that are presented on MHC class II(+) syngeneic antigen-presenting cells. These results strongly suggest that rejection occurs exclusively through the indirect pathway of T-cell activation.

Ivermectin treatment of demodicosis in 56 hamsters

Fifty-six hamsters with demodicosis were treated with daily oral administration of ivermectin (0.3 mg/kg). Thirty-three cases (58.9%) were cured and 6 cases (10.7%) had improved clinically but needed to continue treatment. Of 5 cases (8.9%) who relapsed within 3 months and were retreated with ivermectin, 4 were cured and 1 needed further treatment. Five cases (8.9%) had improved clinically but died within 3 months. Seven cases (12.5%) had not improved and died within 3 months. Overall 49 (87.5%) hamsters had improved clinically. No significant differences in prognosis of demodicosis were detected according to sex, breed, age and clinical features, but the prognosis of demodicosis in hamsters with concurrent disease was poor.

[Treatment outcomes with vinorelbine for metastatic breast cancer patients previously treated with both doxorubicin and docetaxel]

The purpose of this study was to evaluate the efficacy and toxicity of weekly vinorelbine (VNB) in patients with metastatic breast cancer previously treated with both adriamycin (ADM) and docetaxel (TXT). VNB was administered weekly at the dose 20 mg/m2 by i.v. infusion over 20 minutes followed by flushing the vein with 100 ml of normal saline. From June 1999 to August 2000, ten patients were enrolled in this study. Patient characteristics were that the cumulative doses (median) of previous ADM and TXT were 300 mg (range, 120-880 mg), 560 mg (range, 120-960 mg) respectively. The median number of metastatic sites was four, with poor performance status (ECOG 1-2: 40%, 3-4: 60%). The median cycles of weekly VNB were seven (range: 2-12). Two of 10 assessable patients obtained partial response, with an overall response rate of 20%. The main toxicity (NCI grade 4) was leukopenia in 10% of 10 patients. Phlebitis (grade 2) was observed in 4 of 10 patients (40%). VNB is an active agent against metastatic breast cancer pretreated with both ADM and TXT, possessing no severe toxicities.

Conservative treatment for cervical spondylotic myelopathy. prediction of treatment effects by multivariate analysis

BACKGROUND CONTEXT

Many studies have suggested only slight effects of conservative treatment on cervical spondylotic myelopathy (CSM), whereas a few reports describe conservative treatment as being effective. This suggested the influence of various factors on treatment outcomes.

PURPOSE

We investigated symptomatic changes after conservative treatment in patients based on a clear understanding of the effects and limitations of conservative treatment.

STUDY DESIGN

We have encountered cases that showed symptomatic improvement with conservative treatment and became interested in the effectiveness of conservative treatment for CSM and whether other factors affect the results of conservative treatment.

PATIENT SAMPLE

We have analyzed the results of conservative treatment for CSM in 69 cases, derived from a population of 101 CSM cases.

OUTCOME MEASURES

Symptoms at the time of the first examination were compared with those at the final examination, and the patients were classified into three groups showing improvement, no change or exacerbation.

METHODS

Improvement or exacerbation of the symptoms was used as dependent variables and the collected factors as independent variables, and logistic regression was performed on these variables.

RESULTS

Multivariate analysis showed significant correlation between clinical outcome and the disease duration and the presence of rigorous conservative treatment.

CONCLUSIONS

Conservative treatment for CSM is considered to be effective if it is performed intensively in selected patients. In treating CSM, the therapeutic approach must be selected first in consideration of the patient's disease duration. Conservative treatment must be carried out intensively after sufficient explanation to the patients. Timely surgical intervention is considered to be important if the symptoms show no change or exacerbation with conservative treatment.