Duration and clinical outcome of dual antiplatelet therapy after percutaneous coronary intervention: a retrospective cohort study using a medical information database from Japanese hospitals

In this real-world, retrospective cohort study of 9753 patients in Japan prescribed dual antiplatelet therapy (DAPT) following percutaneous coronary intervention (PCI), we investigated DAPT duration and determined factors associated with early DAPT discontinuation and with event rates in patients who discontinued DAPT. The study period was April 1, 2012–March 31, 2018; endpoints comprised composite efficacy [death, myocardial infarction (MI), and stroke] and bleeding (intracranial, gastrointestinal, and requiring transfusion) endpoints. Overall, 68.8% of patients were continuing DAPT at 3 months post-PCI. Patients without major efficacy or safety events within 3 months after index PCI were included in a landmark analysis set (LAS; n = 7056), and categorized as DAPT ≥ 3 months (continuation) versus < 3 months (discontinuation). In the two LAS analysis groups, there was no difference in the composite bleeding endpoint (P = 0.067), although the incidence of the composite efficacy endpoint was higher in the discontinuation group (P < 0.001). In multivariate regression analysis, age ≥ 75 years, minor bleeding after PCI, history of cerebral infarction, history of cerebral or gastrointestinal bleeding, atrial fibrillation, dialysis, and anticoagulant use after PCI were associated with early DAPT discontinuation. Acute coronary syndrome, history of MI, kidney disorder, and anticoagulant use after PCI were associated with the composite efficacy endpoint in the discontinuation group. In conclusion, early DAPT discontinuation is more likely in patients at high bleeding risk, but may influence the occurrence of ischemic events in these patients. Determination of DAPT duration should take into account potential ischemic risk, even in patients at high bleeding risk.

Predictive factors for achievement of mucosal healing by budesonide 2-mg foam in ulcerative colitis: a pooled analysis of data from two clinical trials

Background/Aims

Mucosal healing (MH) of distal lesions in ulcerative colitis (UC) has recently been confirmed with budesonide 2-mg foam (BF) treatment in 2 clinical trials; however, few studies have investigated the predictive factors for complete MH.

Methods

We conducted a post hoc analysis using pooled data from phase II and III clinical trials evaluating the efficacy and safety of BF for UC. Additionally, we analyzed the relationships between complete MH and baseline factors and clinical symptoms from baseline to week 6.

Results

Among the 291 Japanese patients from the 2 pooled clinical studies, 119 patients in the BF twice a day group and 117 in the placebo group were included in the full analysis set. The proportion of patients with a rectal bleeding (RB) subscore of 0 was significantly higher in the BF group than in the placebo group after a 5-day treatment (P<0.05). After a 2-day treatment, significantly more patients in the BF group had a stool frequency (SF) subscore of 0 than patients in the placebo group (P<0.05). Multivariate analysis showed that complete MH at week 6 was influenced by baseline SF subscore and 5-aminosalicylic acid (5-ASA) enema or suppository use (P=0.0086 and P=0.0015, respectively). The relationship between complete MH at week 6 and RB subscore after week 2 was also confirmed.

Conclusions

Normal SF at baseline, history of 5-ASA topical product use, and elimination of RB after week 2 are suggested predictors of complete MH at week 6 with twice-daily BF treatment.

Retrospective analysis of medical costs and resource utilization for severe hypoglycemic events in patients with type 2 diabetes in Japan

AIMS/INTRODUCTION

The present study aimed to describe hospital utilization and examine actual medical costs for severe hypoglycemic events in patients with type 2 diabetes mellitus in Japan.

MATERIALS AND METHODS

Medical resource utilization associated with severe hypoglycemia was evaluated using a receipt database of acute-care hospitals in Japan. Patients with type 2 diabetes treated with antihyperglycemic agents were included. Severe hypoglycemic events were identified and divided into two groups: with or without hospitalization. Total and attributable medical costs per event were calculated based on the actual medical treatment after severe hypoglycemic events. Attributable costs were estimated from the receipt codes directly associated with the treatment of severe hypoglycemia.

RESULTS

In the hospitalized patients, the median length of hospital stay was 11 days, and the median total and attributable medical costs were ¥402,081 and ¥302,341, respectively. The majority of the hospitalized patients underwent a radiographic examination and general blood tests. Apart from the hospitalization costs, the costs associated with diagnosis accounted for 29.6% of the total medical costs. In the outpatients, 60.6% visited hospitals only once for the severe hypoglycemic event, whereas 11.4% visited hospitals daily for a week after the severe hypoglycemic event. The mean number of hospital visits of the outpatient after a severe hypoglycemic event was 2.7 ± 2.6 days. The median total and attributable medical costs were ¥265,432 and ¥4,628, respectively.

CONCLUSIONS

Significant medical resources are used for the treatment of severe hypoglycemic events of patients with type 2 diabetes in Japan.

Incidence rate and patient characteristics of severe hypoglycemia in treated type 2 diabetes mellitus patients in Japan: Retrospective Diagnosis Procedure Combination database analysis

AIMS/INTRODUCTION

To evaluate the incidence rate of and identify factors associated with severe hypoglycemic episodes in patients with treated type 2 diabetes mellitus.

MATERIALS AND METHODS

Using Diagnosis Procedure Combination hospital-based medical database, we carried out a retrospective cohort study to assess the incidence rate of severe hypoglycemia in treated type 2 diabetes mellitus patients. We evaluated the associations between severe hypoglycemia and age, sex, complications, and current use of insulin or sulfonylurea (SU) in a nested case-control study.

RESULTS

Of 166,806 eligible patients, 1,242 had episodes of severe hypoglycemia during the observational period. The incidence rate of the first hypoglycemic events was 3.70/1,000 patient years. Based on the nested case-control analysis, age was associated with hypoglycemic events with adjusted odds ratios (ORs) of 1.64 or 65-74-year-old patients and 3.79 for ≥75-year-old patients in comparison with 20-64-year-old patients. Comorbidities, such as cognitive impairment, cancer, macrovascular disease and diabetic complications (retinopathy, nephropathy and neuropathy), were associated with severe hypoglycemia, with adjusted ORs ranging from 1.25 to 3.80. Severe hypoglycemic events also increased in patients with current use of both SU and insulin, either SU or insulin, with adjusted ORs of 18.36, 6.31 or 14.07, respectively, compared with patients with other antihyperglycemic agents. In patients with an SU glimepiride, adjusted ORs increased dose-dependently from 3.65 (≤1 mg) to 13.34 (>2 mg).

CONCLUSIONS

The incidence rate of severe hypoglycemia in this cohort was 3.70/1,000 patient years. Age, cognitive impairment, cancer, diabetic complications, current use of insulin + SU and SU dosage were identified as risk factors for severe hypoglycemia.

Real-world evidence of raloxifene versus alendronate in preventing non-vertebral fractures in Japanese women with osteoporosis: retrospective analysis of a hospital claims database

We conducted a retrospective cohort study using a de-identified hospital administrative claims database to assess the risk of non-vertebral fracture in Japanese women with osteoporosis treated with raloxifene compared with alendronate. The study included Japanese women ≥50 years of age with newly initiated alendronate or raloxifene treatment between July 2008 and March 2013 (index date was defined as the day of first prescription for alendronate or raloxifene), and had any claim with an osteoporosis definition during the study period. A total of 37,056 patients in the database initiated treatment, and there were 4802 and 1250 patients included in the alendronate and raloxifene analysis groups, respectively. The mean observation period in the alendronate group (529.2 days) was significantly longer than that for the raloxifene group (473.5 days, P < 0.001). Non-vertebral fractures accumulated linearly, at a similar rate, for both study drugs: incidence at 1 year was 2.83 and 2.64% for the alendronate and raloxifene groups, respectively. For the relative risk of non-vertebral fracture within 1 year, the adjusted hazard ratio was 0.933 for raloxifene versus alendronate, indicating that the relative risk of non-vertebral fracture was similar for the two drugs. The effectiveness of raloxifene in preventing non-vertebral fractures in Japanese women with osteoporosis was similar to that of alendronate. Therefore, raloxifene may be worthy of consideration as an alternative treatment.

Recurrent Stroke and Bleeding Events after Acute Cardioembolic Stroke-Analysis Using Japanese Healthcare Database from Acute-Care Institutions

BACKGROUND

To understand the reality of patients who experienced a cardioembolic stroke (CES) is important because of the high incidence of recurrent stroke and the need to account for bleeding risk in relation to the need for anticoagulation treatment. We elucidated the current real-world medical care in patients who had a CES and identified the risk factors for recurrent stroke.

METHODS AND RESULTS

The study comprised 9804 patients who were diagnosed with CES between April 2008 and September 2013 as identified in a healthcare database used by acute-care institutions in Japan. We analyzed the incidence and risk factors of stroke and bleeding events in CES patients. The incidence of stroke was 10.3% during the median observation period of 68 days, mainly consisting of recurrent CES (8.5%). The incidence of bleeding events and intracranial bleeding was 10.3% and 7.0%, respectively. The recurrence of ischemic stroke was significantly lower, and brain hemorrhage was significantly higher in the anticoagulation treatment group. The factors related to an increased risk of stroke were a history of cerebral infarction or transient ischemic attack, diabetes, and increase of CHA₂DS₂-VASc and CHADS₂ scores. The risk factors for bleeding events were hypertension, renal dysfunction, and use of proton pump inhibitors (PPIs).

CONCLUSIONS

The patients who experienced CES had a high rate of recurrent stroke or CES, mainly consisting of recurrent CES. Although anticoagulation may be beneficial for reducing recurrence of ischemic stroke, careful management is required given consideration of increased risk of brain hemorrhage during anticoagulation treatment, especially for patients with hypertension, renal dysfunction, and use of PPIs.

Incidence of venous thromboembolism and bleeding events in patients with lower extremity orthopedic surgery: a retrospective analysis of a Japanese healthcare database

BACKGROUND

Orthopedic surgeries of lower extremities such as total knee arthroplasty (TKA), total hip arthroplasty (THA), and hip fracture surgery (HFS) are widely considered to carry a high risk of developing deep venous thrombosis (DVT) and pulmonary thromboembolism (PTE). Growing attention to epidemiological studies using a healthcare database led us to quantify the risks using a Japanese database to reveal recent medical care for such events.

METHODS

The study comprised 36,947 patients who had undergone orthopedic surgeries of the lower extremities and whose medical information from April 2008 to September 2013 was available. The source population of the database was derived from 100 acute-care hospitals with Diagnosis Procedure Combination. The events were defined by diagnosis, medication, imaging, and laboratory tests.

RESULTS

A breakdown of patients who underwent orthopedic surgeries by type of surgery showed 13.6% for TKA, 10.4% for THA, 56.8% for HFS, 1.5% for rupture of Achilles tendon, and 18.0% for simple fracture of lower extremities. The incidence for DVT, PTE, and bleeding events by type of surgery was 1.3, 0.2, and 1.0% for TKA; 0.9, 0.2, and 1.1% for THA; and 0.4, 0.1, and 1.8% for HFS, respectively. The population for risk factor analysis consisted of patients with similar background factors who underwent TKA, THA, or HFS. The statistically significant risk factors for PTE analyzed by the backward elimination procedure in a multivariate model were female sex, history of venous thromboembolism (VTE), thrombophilia, and varicose veins of lower extremity.

CONCLUSIONS

The incidence of DVT, PTE, and bleeding events and the risk factors for DVT and PTE in patients by type of orthopedic surgeries of lower extremities found in our study are considered to be rational as they reflect evidence from real-world cases.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry UMIN000012667.

Predictors of venous thromboembolism recurrence and the bleeding events identified using a Japanese healthcare database

BACKGROUND

Treatment to prevent the recurrence of venous thromboembolism (VTE) and prevent bleeding events should be given to patients with VTE in an appropriate balance in relation to relevant predictors. We elucidated the current medical care in a real world setting and quantified predictors using a Japanese healthcare database.

METHODS

The study included 3578 patients who were diagnosed with VTE between April 2008 and September 2013 at a Japanese acute-care hospital and included in the hospital database. Twenty-four patients who had a VTE event during the 180-day period after enrollment were excluded. We analyzed the incidence of recurrent VTE, incidence of bleeding events, and predictors in VTE patients. Events were defined by disease, medication, imaging, and laboratory testing, among other factors.

RESULTS

The rate of recurrence of VTE events was 7.2 per 100 patient-years. The incidence rate of bleeding events was 8.3 per 100 patient-years. The presence of malignant disease, antipsychotic drugs, and nonsteroidal anti-inflammatory drugs increased the risk for recurrent VTE. The predictors for bleeding events were malignant disease, central venous catheterization, cancer chemotherapy, stroke, and diabetes.

CONCLUSIONS

These findings obtained from healthcare database suggest predictors either for recurrent VTE and bleeding that should be considered when selecting treatment to reduce the risk of recurrent VTE and mitigate bleeding.

The Direct Cost of Parkinson Disease at Juntendo Medical University Hospital, Japan

Objective Many studies on the cost of Parkinson disease (PD) have been published; however, there are limited studies pertaining to this issue in Asia. This study looks to assess the direct medical costs of patients with PD at a university hospital in Japan by calculating the average monthly direct medical costs of PD patients from July to December 2008. Methods We enrolled 724 consecutive patients (411 women and 313 men) with PD who were registered in Japan's "Specified Disease Treatment Research Program" and obtained data on the total direct medical costs of all patients. Results Values are reported as the mean (standard deviation). The major finding of the direct medical cost analysis was that the outpatient clinic cost per subject (n=715) was USD 485.74 (376.31) per month. A multivariate analysis revealed that a younger age, the presence of wearing-off, hallucination, and longer disease duration increased the direct medical cost significantly. Disease severity had no influence on the direct medical costs. A longer disease duration was significantly correlated with higher hospitalization costs. Conclusion The direct medical cost of PD in Japan was found to be similar to that in Western countries. Costs due to productivity loss exceeded the direct costs, and they may be reduced through the better integration of PD patients in the work environment.

Effects of mammal host diversity and density on the infection level of Trypanosoma cruzi in sylvatic kissing bugs

Several reports have described host species diversity and identity as the most important factors influencing disease risk, producing either dilution or amplification of the pathogen in a host community. Triatomine vectors, mammals and the protozoan Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae) Chagas are involved in the wild cycle of Chagas disease, in which infection of mammals occurs by contamination of mucous membranes or skin abrasions with insect-infected faeces. We examined the extent to which host diversity and identity determine the infection level observed in vector populations (i.e. disease risk in humans). We recorded infection in triatomine colonies and on the coexisting host mammalian species in semi-arid Chile. Host diversity, and total and infected host species densities are used as predictor variables for disease risk. Disease risk did not correlate with host diversity changes. However, the densities of each infected rodent species were positively associated with disease risk. We suggest that the infected host density surrounding the vector colonies is a relevant variable for disease risk and should be considered to understand disease dynamics. It is crucial to pay attention on the spatial scale of analysis, considering the pattern of vector dispersal, when the relationship between host diversity and disease risk is studied.

High-density lipoprotein cholesterol is positively associated with hypertension in apparently healthy Japanese men and women

Among five components of metabolic syndrome, high-density lipoprotein (HDL) cholesterol is unique because it is not significantly associated with blood pressure. This study looks at cross-sectional relationships between HDL cholesterol and hypertension using medical check-up data from 1803 apparently healthy Japanese men aged 49.9 +/- 9.0 years, and 1150 Japanese women aged 49.5 +/- 9.0 years. Pearson's correlation coefficients between systolic blood pressure (SBP)/diastolic blood pressure (DBP) and HDL cholesterol were -0.01 (ns)/-0.01 (ns) in men and -0.04 (ns)/-0.01 (ns) in women. The standardised partial regression coefficient of HDL cholesterol for SBP/DBP (mmHg) controlling for age, body mass index (BMI), fasting plasma glucose (FPG), triglycerides, high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein (LDL) cholesterol were 0.15 (P < 0.0001)/0.15 (P < 0.0001) in men and 0.10 (P < 0.0001)/0.12 (P < 0.0001) in women. The odds ratio (OR; 95% confidence interval [CI]) of a 1 mg/dL increment of HDL cholesterol for hypertension controlling for age, BMI, FPG, triglycerides, hs-CRP, LDL cholesterol, metabolic syndrome, diabetes, exercise status, drinking status, and smoking status was 1.03 (1.02-1.04; P < 0.001) in men and 1.03 (1.01-1.05; P = 0.002) in women. Thus, HDL cholesterol was independently positively associated with hypertension in apparently healthy Japanese men and women.

Influence of multiple genetic polymorphisms on genitourinary morbidity after carbon ion radiotherapy for prostate cancer

PURPOSE

To investigate the genetic risk of late urinary morbidity after carbon ion radiotherapy in prostate cancer patients.

METHODS AND MATERIALS

A total of 197 prostate cancer patients who had undergone carbon ion radiotherapy were evaluated for urinary morbidity. The distribution of patients with dysuria was as follows: Grade 0, 165; Grade 1, 28; and Grade 2, 4 patients. The patients were divided (2:1) consecutively into the training and test sets and then categorized into control (Grade 0) and case (Grade 1 or greater) groups. First, 450 single nucleotide polymorphisms (SNPs) in 118 candidate genes were genotyped in the training set. The associations between the SNP genotypes and urinary morbidity were assessed using Fisher's exact test. Then, various combinations of the markers were tested for their ability to maximize the area under the receiver operating characteristics (AUC-ROC) curve analysis results. Finally, the test set was validated for the selected markers.

RESULTS

When the SNP markers in the SART1, ID3, EPDR1, PAH, and XRCC6 genes in the training set were subjected to AUC-ROC curve analysis, the AUC-ROC curve reached a maximum of 0.86. The AUC-ROC curve of these markers in the test set was 0.77. The SNPs in these five genes were defined as "risk genotypes." Approximately 90% of patients in the case group (Grade 1 or greater) had three or more risk genotypes.

CONCLUSIONS

Our results have shown that patients with late urinary morbidity after carbon ion radiotherapy can be stratified according to the total number of risk genotypes they harbor.

The free-radical scavenger, edaravone, augments NO release from vascular cells and platelets after laser-induced, acute endothelial injury in vivo

In vitro and in vivo experimental models have demonstrated that vascular endothelial function is significantly impaired as a result of oxidative stress, mediated by the generation of oxygen-derived free radicals in response to chronic or acute inflammation. In particular, super-oxide () at specific concentrations leads to the impairment of nitric oxide (NO) bioactivity, and it is known that NO plays a fundamental role in the maintenance of vascular homeostasis. The relationship between reactive oxygen species (ROS) and NO release in thrombosis-related endothelial damage in the peripheral microvasculature remains unclear, however. The purpose of the present study was to investigate the effect of the free-radical scavenger, edaravone, on NO synthesis and thrombotic potential in arterioles after exposure to laser irradiation. Highly sensitive electrochemical NO microsensors were positioned in femoral arterioles of mice, and the kinetics of NO release were recorded in response to standardized laser irradiation in vivo. In addition, images of NO release from damaged vascular cells were investigated in a similar rat model using the NO-sensitive dye 4,5-diaminofluorescein diacetate (DAF-2DA). Thrombogenesis was assessed in carotid arterioles by continuous video microscopy using image analysis software. Laser irradiation led to NO release from perturbed endothelial cells and from platelet-rich thrombi. Edaravone had no significant effect on NO release in non-laser treated, intact endothelium compared with placebo. In contrast, edaravone demonstrated a dose-dependent effect on NO release and thrombogenicity. At a concentration of 10.5 mg/kg per h, edaravone promoted a 5-fold increase in NO and a reduction in platelet-rich thrombus volume to 58% of the placebo values. Our data provide direct evidence to confirm that acute endothelial damage in peripheral microvessels initially induces NO release and that the free-radical scavenger, edaravone, augments NO synthesis leading to suppression of platelet thrombus formation.

Analysis of non-genetic risk factors for adverse skin reactions to radiotherapy among 284 Breast Cancer patients

OBJECTIVES

We analyzed non-genetic risk factors for adverse skin reactions to irradiation at 4 collaborating Japanese institutions, to design future investigation into genetic risk factors for adverse skin reactions to irradiation in a multicenter setting.

METHODS

From April 2001, 284 breast cancer patients, who underwent radiotherapy with breast-conserving surgery, were enrolled from 4 collaborating institutions in Japan. We graded skin reactions according to international scoring systems. Clinical factors were tested against adverse effects.

RESULTS

Grade 1+ skin reactions were observed in 261 (92%) of the patients in less than 3 months, 118 (42%) at 3 months, and 29 (10%) at 6 months in the late phase. Univariate analysis of treatment risk factors (such as the use of a multi-leaf colimeter, wedge-filter, or immobilization device) for skin reactions revealed a significant association (p< 0.0001). After a variable selection procedure with logistic regression, the institution, operative procedure, and magnitude of photon energy remained significantly associated with acute skin reactions. Only the institution was an explanatory variable for skin reactions at 3 and 6 months in the final logistic model.

CONCLUSION

After stratification, substantial remaining variations in the occurrence of skin reactions of a given level suggested that individual genetic factors contribute markedly to individual radiosensitivity. Analysis of genetic factors associated with adverse effects would be possible by stratifying patients according to institution. Selection of eligible institutions, where appropriate treatment modalities could be performed, would also be possible when planning such a study.

The effect of dietary bacillus natto productive protein on in vivo endogenous thrombolysis

The influence of dietary bacillus natto productive protein (BNPP) on endogenous thrombolysis was investigated in the rat. Animals were given a standard feed for 14 weeks, to which 0.2 or 1% BNPP was added. Thrombolysis was evaluated using an He-Ne laser-induced thrombosis model in mesenteric microvessels. Changes in thrombus volume, reflecting thrombolysis, decreased to 82% of the initial value in the control group. In contrast, the thrombus volume decreased to 67% in the animals fed 0.2% BNPP, and decreased to 51% in the group given 1% BNPP. The extent of thrombolysis in the 1% BNPP group was equivalent to that seen in animals treated with a bolus intravenous infusion of 0.2 mg/kg tissue plasminogen activator. The results demonstrated that the dietary administration of BNPP enhanced endogenous thrombolysis in a dose-dependent manner. Argatroban (2 mg/kg/h) enhanced endogenous fibrinolysis only in control animals, but not in the BNPP groups. The results support the suggestion that dietary supplementation with BNPP may provide a simple means to promote fibrinolysis not only in the treatment of thromboembolism but also in the prevention of venous occlusion.

Varying the ratio of dietary n−6/n−3 polyunsaturated fatty acid alters the tendency to thrombosis and progress of atherosclerosis in apoE−/− LDLR−/− double knockout mouse

We have investigated the influence of dietary n-6/n-3 (ù-6/ù-3) polyunsaturated fatty acid-balance on the tendency to arterial thrombosis and the progress of atherosclerosis in apoE-/- LDLR-/- double knockout mouse. Homozygous apoE-/- LDLR-/- double knockout mouse (DKO mice, 129XC57BL/6J background) and male C57BL/6 mice aged 6 weeks were divided into four groups. Each group was fed a diet containing a different n-6/n-3 ratio (Group l: 0.29; Group 2: 1.43; Group 3: 5.00; Group 4: 8), prepared with high linolenic (LNA) flaxseed oil (n-3 rich) and high linoleic (LA) safflower oil (n-6 rich). There were no statistical differences in the gain in body weight between the four groups. After 16 weeks, plasma triglyceride and LDL levels in Group 1 were significantly lower than in the other groups. Conversely, HDL was the highest. After 8 and 16 weeks, the tendency to arterial thrombosis was assessed using a He-Ne laser-induced thrombosis model. The degree of atherosclerosis was measured using the entire aorta method employing image analysis software. The n-6/n-3 ratio had a dose-dependent antithrombotic effect (thrombus volume decreased 23%, Group 1 vs. Group 4), In addition, the extent of atherosclerosis was less in the animals fed a low n-6/n-3 ratio compared with the high n-6/n-3 ratio group (atherosclerotic area decreased 40%, Group 1 vs. Group 4). The lowest n-6/n-3 ratio tested (0.29) was the most effective in suppressing the thrombotic and atherosclerotic parameters in these DKO mice.

Unidimensional scale for dementia

A cognitive test comprising 27 subscales was administered to 262 demented patients and 92 normal subjects. Principal factor analysis followed by varimax and Harris-Kaiser rotation and Guttman's scalogram analysis was performed. The analysis yielded three factors, i.e. "recent memory", "immediate memory or attention" and "remote memory". The relationships between the three-dimensional distribution of the scores and the DSM-IIIR grade of dementia indicated the existence of a continuum of dementia severity. Scalogram analysis showed unidimensionality in the difficulty level of the subscales as well as in the severity of the cases. Thus, the simple summary score can be used as a good measure of the severity of dementia.

Reprimo, a new candidate mediator of the p53-mediated cell cycle arrest at the G2 phase

A novel gene, Reprimo, in which induction in cells exposed to X-irradiation is dependent on p53 expression, has been isolated. Ectopic p53 expression results in the induction of its mRNA. Reprimo is a highly glycosylated protein and, when ectopically expressed, it is localized in the cytoplasm and induces G(2) arrest of the cell cycle. In the arrested cells, both Cdc2 activity and nuclear translocation of cyclin B1 are inhibited, suggesting the involvement of Reprimo in the Cdc2.cyclin B1 regulation pathway. Thus, Reprimo may be a new member involved in the regulation of p53-dependent G(2) arrest of the cell cycle.

Noxa, a BH3-only member of the Bcl-2 family and candidate mediator of p53-induced apoptosis

A critical function of tumor suppressor p53 is the induction of apoptosis in cells exposed to noxious stresses. We report a previously unidentified pro-apoptotic gene, Noxa. Expression of Noxa induction in primary mouse cells exposed to x-ray irradiation was dependent on p53. Noxa encodes a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family of proteins; this member contains the BH3 region but not other BH domains. When ectopically expressed, Noxa underwent BH3 motif-dependent localization to mitochondria and interacted with anti-apoptotic Bcl-2 family members, resulting in the activation of caspase-9. We also demonstrate that blocking the endogenous Noxa induction results in the suppression of apoptosis. Noxa may thus represent a mediator of p53-dependent apoptosis.

Loss of transcription factor IRF-1 affects tumor susceptibility in mice carrying the Ha-ras transgene or nullizygosity for p53

The transcription factor IRF-1 has been implicated in tumor suppression: IRF-1 suppresses cell transformation and mediates apoptosis in vitro. Here we show that the loss of IRF-1 alleles per se has no effect on spontaneous tumor development in the mouse but dramatically exacerbates previous tumor predispositions caused by the c-Ha-ras transgene or by nullizygosity for p53. Grossly altered tumor spectrum, as compared to p53-null mice, was also observed in mice lacking both IRF-1 and p53, and cells from these mice show significantly higher mutation rate. Our results suggest that IRF-1 is a new member of the tumor susceptibility genes.

[The critical appraisal of QOL questionnaire for prostate cancer patients]

BACKGROUND

Prostate cancer is a common malignancy that affects Japanese elderly men. Its incidence is increasing, recently, and its treatments are various. The measurement of quality of life (QOL) has become important for the evaluation of and selection of treatments. In Japan, however, there is no standard way of measuring QOL for prostate cancer patients, except the Japanese version of the EORTC QOL questionnaire for prostate cancer patients. We examined the validity and feasibility of this translated EORTC QOL questionnaire for prostate cancer patients.

METHODS

Sixty-nine prostate cancer patients who were under treatment in 4 hospitals were selected for this study. We applied the content validity, the factorial validity which was analyzed by the oblique principal component cluster analysis, the internal consistency analyzed by the alpha coefficient of Cronbach, the convergent validity which was used GHQ, IPSS and PS as external measures, and the feasibility.

RESULTS

This questionnaire showed good internal consistency, as the alpha coefficient was 0.61 to 0.90 in all domains, except for sex life, which was the lowest. This questionnaire was classified into 7 clusters by the oblique principal component cluster analysis. Consequently, the factorial validity was good, except for items regarding sex life. As domains correlate well with external measures except in sex life, the convergent validity was good. It was suggested that only two items were not acceptable in regard to the content validity and the feasibility, and that the translation into Japanese of 2 items was inadequate.

CONCLUSIONS

Our study suggests that the Japanese version of the EORTC QOL questionnaire for prostate cancer patients demands improvement for the practical employment in clinical trials, as there is a problem of translation and feasibility.

Functionally inactivating point mutation in the tumor-suppressor IRF-1 gene identified in human gastric cancer

Loss of heterozygosity (LOH) observed in human tumors strongly suggests the existence of (a) tumor-suppressor gene(s) at the concerned locus. A series of studies has revealed that LOH on the long arm of chromosome 5 (5q) frequently occurs in differentiated gastric adenocarcinomas. Furthermore, it has been shown that the interferon regulatory factor-1 (IRF-1) locus on chromosome 5q31.1 is one of the common minimal regions of LOH in these cancers. IRF-1 is a transcriptional activator that shows tumor-suppressor activity in the mouse. In the present study, we examined the sequence of the IRF-1 gene in 9 cases of histologically differentiated gastric adenocarcinomas, all of which exhibited LOH at the IRF-1 locus. We identified a mis-sense mutation in the residual allele in one case. This mutated form of IRF-1 showed markedly reduced transcriptional activity. In addition, overexpression of wild-type IRF-1 induced cell-cycle arrest, whereas such activity was attenuated in the mutant IRF-1. These results suggest that the loss of functional IRF-1 is critical for the development of human gastric cancers.

Cloning and characterization of a GC-box binding protein, G10BP-1, responsible for repression of the rat fibronectin gene

Fibronectin (FN) is an extracellular matrix protein that connects the extracellular matrix to intracellular cortical actin filaments through binding to its cell surface receptor, alpha5beta1, a member of the integrin superfamily. The expression level of FN is reduced in most tumor cells, facilitating their anchorage-independent growth by still unclarified mechanisms. The cDNA clone encoding G-rich sequence binding protein G10BP-1, which is responsible for repression of the rat FN gene, was isolated by using a yeast one-hybrid screen with the G10 stretch inserted upstream of the HIS3 and lacZ gene minimal promoters. G10BP-1 comprises 385 amino acids and contains two basic regions and a putative zipper structure. It has the same specificity of binding to three G-rich sequences in the FN promoter and the same size as the G10BP previously identified in adenovirus E1A- and E1B-transformed rat cells. Expression of G10BP-1 is cell cycle regulated; the level was almost undetectable in quiescent rat 3Y1 cells but increased steeply after growth stimulation by serum, reaching a maximum in late G1. Expression of FN mRNA is inversely correlated with G10BP-1 expression, and the level decreased steeply during G1-to-S progression. This down regulation was strictly dependent on the downstream GC box (GCd), and base substitutions within GCd abolished the sensitivity of the promoter to G10BP-1. In contrast, the level of Sp1, which competes with G10BP for binding to the G-rich sequences, was constant throughout the cell cycle, suggesting that the concentration of G10BP-1 relative to that of Sp1 determines the expression level of the FN gene. Preparation of glutathione S-transferase pulldowns of native proteins from the cell extracts containing exogenously or endogenously expressed G10BP-1, followed by Western blot analysis, showed that G10BP-1 forms homodimers through its basic-zipper structure.

Induction of Sp1 in differentiating human embryonal carcinoma cells triggers transcription of the fibronectin gene

Cells of the human embryonal carcinoma line NEC14 proliferate as densely packed clusters consisting of small, polygonal stem cells and do not express a detectable level of fibronectin (FN). Upon induction of differentiation by treatment with N,N'-hexamethylene bisacetamide (HMBA), the level of FN mRNA increased steeply within 24 h and FN began to be accumulated, along with the organization of actin filaments in the cells. The FN promoter elements required for the activation were analyzed in reference to a cluster of GC boxes by using the chloramphenicol acetyltransferase (CAT) gene fused to 5' sequential-deletion derivatives of the promoter and promoters carrying base substitutions in the GC boxes. Among four GC boxes, GC boxes 2 and 3 had the greatest effect on promoter activation, and base substitutions in these GC boxes resulted in 80% reduction in promoter activity. The pattern of DNA-protein complex formation with these GC boxes changed drastically after induction of differentiation. The extract prepared from undifferentiated NEC14 cells formed fast-migrating complexes (UnD complexes), while the extract prepared from NEC14 cells treated with HMBA for 24 h formed slow-migrating complexes containing Sp1. Both complexes were formed predominantly with GC box 2. Base substitutions within the GC boxes completely abolished the formation of both UnD and Sp1 complexes. Consistent with these changes, the Sp1 level increased steeply within 24 h. Induction of Sp1 expression in NEC14 cells effectively stimulated the promoter activity of the transfected FN promoter-CAT constructs. These results indicate that activation of the FN promoter in differentiating NEC14 cells occurs by the steep induction of Sp1, which prevents an undifferentiated cell factor from binding to the Sp1 sites.

Involvement of the IRF family transcription factor IRF-3 in virus-induced activation of the IFN-beta gene

The virus-induced activation of interferon alpha/beta (IFN-alpha/beta) gene transcription is essential for host defense. The IFN-beta promoter is controlled primarily by the virus-inducible enhancer elements, the IRF-Es. Here we show that IRF-3, an IRF family transcription factor, translocates to the nucleus from the cytoplasm upon virus infection in NIH/3T3 cells. The nuclear IRF-3 is phosphorylated, interacts with the co-activators CBP/p300, and binds specifically to the IFN-beta IRF-E. Furthermore, overexpression of IRF-3 causes a marked increase in virus-induced IFN-beta mRNA expression. Thus, IRF-3 is a candidate transcription factor mediating the activation of the IFN-beta gene.

Type I interferons are essential mediators of apoptotic death in virally infected cells

BACKGROUND

The interferons (IFNs) have been extensively studied in the context of host defence against viral infection. In the established model of IFN action, virally infected cells secrete type I IFNs (IFN-alpha/beta) which induce an antiviral state in uninfected cells. However, it is not clear how IFNs function on the infected cells. It has been reported that cells infected by some viruses die by apoptosis.

RESULTS

In the present study, we found that three types of viruses commonly induce apoptosis in primary cell cultures. Importantly, we observed that virus-induced apoptosis was inhibited by anti-IFN-alpha/beta antibodies, and in cells lacking either the type I IFN receptor 1 (IFNAR1) or its downstream mediator, Stat1 (Signal transducer and activator of transcription 1). IFN-alpha treatment by itself did not induce apoptosis unless it was combined with transfection by double-stranded RNA (dsRNA), which is normally generated during the course of viral infection.

CONCLUSION

These results indicate a novel antiviral function of the type I IFNs, i.e. the selective induction of apoptosis in virally infected cells. In effect, these IFNs have a bifunctional role in limiting the spread of virus; eliciting an antiviral state in uninfected cells while promoting apoptosis in infected cells. Our results may help explain why IFNs are sometimes useful in the treatment of viral diseases and will provide further insight into the mechanisms of virus-induced pathogenesis.

[Reliability and factorial structure of a rating scale for persistent vegetative state]

We developed a new rating scale, Kohnan Vegetative Score, to measure severity and small clinical changes in vegetative state patients. It has 7 items corresponding to the conditions of vegetative state by Japanese Society of Neurosurgery: motor function, food ingestion, urination and defecation, eye movement, vocalization, communication, and facial expression. Each item is rated in 5 ordinal categories: slight (score = 1), mild(2), moderate(4), and extreme(5). The sum of the scores is used as the summary score, which ranges from 7 to 35, and high score means 'severe'. We examined the reliability and the factorial structure of the Kohnan Vegetative Score. The subjects were 10 patients who met the conditions of vegetative state. Four neurosurgeons rated the subjects, and then 2 of them repeated the rating after one week interval. As a measure of reliability, the (weighted) Kappa coefficient proposed Cohen (1960, 1968) was calculated for each item, and the intraclass correlation coefficient (ICC) was calculated for the summary score. To analyze the factorial structure, the factor analysis was carried out. The minimum and the maximum weighted Kappa values were 0.44 and 0.64 for intra-rater reliability, and 0.37 and 0.69 for inter-rater reliability, respectively. Concerning the factorial structure, the contribution of the first factor was 91.5% which indicated the unidimensionality of the scale. The ICC's estimate for the summary score were 0.90 (95% C.I.: 0.766-0.970). On the basis of these results, the Kohnan Vegetative Score has unidimensionality and high reliability enough for a practical use.

[The physical, mental and social impacts of telling prostate cancer patients the true diagnosis]

BACKGROUND

Telling cancer patients the true diagnosis is inevitable to acquire informed consent especially in the Western world. In Japan, however, no such consensus has been established yet. We investigated the influence of telling the true diagnosis on QOL of prostate cancer patients.

METHODS

We measured physical, mental and social aspect of prostate cancer outpatients by the General Health Questionnaire (GHQ) and the international Prostate Symptom Score (I-PSS). Using the general linear models we tried to explore which variables would attribute to "severe depression", "anxiety and insomnia" and "social dysfunction".

RESULTS

No significant differences were found in any of the eight variables (age, performance status, clinical stage, I-PSS and Goldberg's four factors of GHQ) among the two groups that were informed the true diagnosis or not. The correlation structures of "severe depression", "somatic symptoms" and I-PSS are significantly different in the two groups. As a result of the analysis by the GLM, "somatic symptoms", I-PSS and clinical stages had main effect on "severe depression". Also, there was an interaction between the effect of telling the true diagnosis and "somatic symptoms".

CONCLUSION

These results suggest that the mental condition of prostate cancer patients remain stable when they are in good physical condition regardless of being informed the true diagnosis or not. However, the patients who weren't told the true diagnosis have a tendency to get depression accompanying deterioration of physical condition. It is therefore considered that telling the true diagnosis makes the patients understand the changes of their physical conditions and help their mind to be stable.

[Reliability and factorial structure of a rating scale for amyotrophic lateral sclerosis]

The Modified Norris Scale is a rating scale for amyotrophic lateral sclerosis (ALS), which consists of two parts, the Limb Norris Scale and the Norris Bulbar Scale. The Limb Scale has 21 items to evaluate extremity function and the Bulbar Scale has 13 items to evaluate bulbar function. Each item is rated in 4 ordinal categories. Considering the habitual difference, we translated the English scale into Japanese one with minor modification, and added more detailed explanations for all categories of each item. Then we examined reliability and factorial structure of the translated scale. The subjects were 23 patients with motor disturbance and each subject was rated twice by 2-4 neurologists. As a measure of reliability, the Kappa coefficient proposed by Cohen (1960) and Kraemer (1980) was calculated for each item and the intraclass correlation coefficient (ICC) was evaluated for total scores of each of two scales. To analyze the factorial structure, the factor analysis was carried out. The minimum and the maximum Kappa values were .70 and .97 for intra-rater reliability of the Limb Scale's items, .60 and .83 for inter-rater reliability of the Limb Scale's items, .41 and 1.00 for intra-rater reliability of the Bulbar Scale's items and .26 and .81 for inter-rater reliability of the Bulbar Scale's items, respectively. Concerning the factorial structure, the contribution of the first factor was 83.6% for the Limb Scale and that for the Bulbar Scale was 66.7%. This indicates unidimensionality of both Scales. The ICCs for the total scores were .97 (95%C.I. .95-.99) for the Limb Scale and .86 (.73-.93) for the Bulbar Scale, respectively. On the basis of these results, the Scale has unidimensionality and high reliability enough for practical use.

Isolation and characterization of the human inter-alpha-trypsin inhibitor family heavy chain-related protein (IHRP) gene (ITIHL1)

Inter-alpha-trypsin inhibitor (ITI) family heavy chain-related protein (IHRP) is a novel human glycoprotein that shows significant homology in amino acid sequence to proteins of the ITI family heavy chains from human plasma. Three overlapping clones that encode the human inter-alpha-trypsin inhibitor family heavy chain-related protein (IHRP) gene (ITIHL1) were isolated and characterized. The IHRP gene spans 15 kb and is composed of 24 exons from 27 to 207 bp in size with consensus splice sites. The gene codes for the precursor of IHRP, which is similar to inter-alpha-trypsin inhibitor (ITI) family heavy chains. Two major transcription initiation sites were identified in the 5'-flanking region. They contain putative promoter elements, but no typical TATA box. Some exons of this gene showed significant similarities to those of the ITI-H1 gene in nucleotide length and in intron phasing. The tissue-specific transcription of this gene may be due to the presence of binding sites for the hepatocyte nuclear factors LF-A1, HNF-5, NF-IL6, and C/EBP. This gene was found to be localized very close to another unknown gene related to EST (GenBank accession #: R54643, R50663, R50563, H27139, and R54913).

[A clinical evaluation of fluconazole in deep seated fungal infections associated with hematological disorders]

The effectiveness of fluconazole on deep seated fungal infections associated with hematological disorders was evaluated in a multicenter clinical study. The underlying diseases included acute myeloblastic leukemia, acute lymphocytic leukemia, malignant lymphoma, adult T cell leukemia, multiple myeloma and others. Fluconazole (FLCZ) was administrated 100-400 mg/day intravenously or orally to 79 patients with systemic fungal infections complicated with hematological disorders and it was possible to evaluate clinical efficacies in 60 patients. 27 patients were diagnosed as having determinate systemic fungal infections and 33 patients suspected fungal infections. The clinical efficacies were 81.5% (22/27) in patients with diagnosed fungal infections and 57.6% (19/33) in patients with suspected fungal infections. The overall clinical efficacy was 68.3% (41/60). No side effects such as gastrointestinal symptoms, vascular pain and renal dysfunction were observed in this study. As for abnormal laboratory test, transient increases in GOT, GPT, Al-P, LDH, serum Na, Cl and decrease in serum K were observed in 9 patients (11.4%). These results indicated that FLCZ has a high therapeutic efficacy on deep seated fungal infections in patients with hematological disorders.

[Beneficial effects of the combination of idebenone and manidipine 2HCl on neurological deficits and histological changes following cerebrovascular lesions in stroke-prone spontaneously hypertensive rats]

We investigated the effects of the combination of idebenone, an energy metabolism enhancer, and manidipine 2HCl, a dihydropyridine-derivative calcium antagonist, on neurological deficits and histological changes in the brain and kidneys of stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions (stroke). The SHRSP were kept on a 1% NaCl solution as their drinking water to synchronize the onset of stroke. After the onset of stroke symptoms, the salt solution was replaced with tap water. On the day following the onset of stroke, idebenone (50 mg/kg), manidipine 2HCl (2 mg/kg) or a combination of idebenone (50 mg/kg) and manidipine 2HCl (2 mg/kg) was administered orally once a day for 3 weeks. In the combination group and manidipine 2HCl-treated group, the neurological deficits after the onset of stroke were ameliorated during the entire experimentalperiod. Especially, the combination significantly decreased the number of days with severe neurological deficits as compared to the control group. The combination and manidipine 2HCl significantly recovered the decrease in body weight and ameliorated the increase of brain weight, which was mainly caused by edema, significantly as compared to the control group. Manidipine 2HCl ameliorated the histological changes in the brain. In the combination group, the histological changes in both the brain and the kidneys were ameliorated. In conclusion, the combination of idebenone and manidipine 2HCl significantly ameliorated the neurological deficits and the histological changes in the brain and the kidney of SHRSP with stroke as compared to each individual treatment. We concluded that manidipine 2HCl enhances the therapeutic effect of idebenone in the treatment of cerebrovascular diseases.

G10BP, an E1A-inducible negative regulator of Sp1, represses transcription of the rat fibronectin gene

Downregulation of the fibronectin (FN) gene in a rat 3Y1 derivative cell line, XhoC, transformed by the adenovirus E1A and E1B genes seems to be caused by the induction of a negative regulator, G10BP, which binds to three G-rich sequences in the promoter (T. Nakamura, T. Nakajima, S. Tsunoda, S. Nakada, K. Oda, H. Tsurui, and A. Wada, J. Virol. 66:6436-6450, 1992). These are the G10 stretch and two GC boxes consisting of the G10 stretch with one internal C residue insertion. The recognition sequences of G10BP and Sp1 (GGGCGG) overlap in these GC boxes. To analyze the mechanism of the downregulation, G10BP was purified by DNA affinity chromatography, and its molecular mass was estimated to be about 30 kDa. The promoter was modified by substituting the sequence GGGG with ATCC or CTTA in these G-rich sequences, leaving the Sp1 motif intact, and by replacing the Sp1 motif by the T stretch. Transcription of FN promoter-chloramphenicol acetyltransferase fusion genes carrying the base substitution in one or more of these G-rich sequences both in vivo and in vitro revealed that the base substitution in any G-rich sequence results in reduction of promoter activity, although the downstream GC box (GCd) plays a primary role. The addition of G10BP severely inhibited the activities of the FN promoters carrying the wild-type GCd in vitro, while the promoters carrying the mutant GCd were unaffected. The binding affinity of G10BP and Sp1 to each of the G-rich sequences, analyzed by gel shift assays, indicated that G10BP binds strongly to the GCd, moderately to the G10 stretch, and weakly to GCu, while Sp1 binds strongly to GCu, moderately to GCd, and weakly to the G10 stretch. Sp1 binding to GCd and the G10 stretch was inhibited by G10BP, while binding to GCu was unaffected. These results indicate that FN gene transcription is inhibited in XhoC cells primarily by exclusion of Sp1 binding to GCd by G10BP and that G10BP is a new class of Sp1 negative regulator.

Determination of the active site of CD59 with synthetic peptides

CD59 inhibits the formation of membrane attack complex (MAC) of human complement by binding to C8 and C9 in the nascent membrane attack complex and inhibiting C9 binding to C8 in C5b-8 and C9 polymerization. Considering five disulfide bridges of CD59, we divided the molecule into two portions and synthesized the two peptides. One represented an amino-terminal half, P1-41, consisting of residues 1-41, while another represented a carboxyl-terminal half, P42-77, consisting of residues 42-77. P1-41 inhibited the MAC formation much more strongly than P42-77, indicating that the amino-terminal half contained the active site. We further synthesized P4-18 that consisted of residues 4-18 and P19-41 that consisted of residues 19-41. The activity of P4-18 was less than that of P19-41. Surprisingly, P19-41 showed higher activity than P1-41 and was comparable to urine CD59. Residues 19-41 were further divided into two portions: P20-25 which consisted of residues 20-25 and P27-38 which consisted of residues 27-38. Although their activities were significantly less than the activity of P19-41, P27-38 showed higher activity than P20-25. Residues 27-38 were further divided into three portions: P27-32 which consisted of residues 27-32, P30-34 which consisted of residues 30-34 and P33-38 which consisted of residues 33-38. When these peptides were assayed for the activities, all of them showed significant activities, even though they needed 10-fold more concentrations than P19-41. These data suggest that the portion made up of residues 27-38 is the active site constituting the binding site to C8 and C9.

Purification and characterization of a novel glycoprotein which has significant homology to heavy chains of inter-alpha-trypsin inhibitor family from human plasma

Plasmapheresis with a dextran sulfate column is a treatment for patients with hypercholesteremia. When proteins bound to the column during the treatment were fractionated to prepare some known proteins, we found a 57 kDa glycoprotein designated GP57 which showed a new N-terminal amino acid sequence. Western-blot analysis of human plasma revealed that only a 120 kDa protein, GP120, reacted with anti-GP57 antibody. Since GP120 and GP57 had an identical N-terminal amino acid sequence, GP120 is probably the intact form of GP57. The isoelectric point of GP120 was 6.8. N-Glycanase treatment decreased the molecular weight of GP120 by 15 kDa. Neuraminidase and O-glycanase, however, did not affect the molecular weight. Amino acid sequence analyses of the lysylendopeptidase digest of GP120 revealed significant homology to the heavy chains of inter-alpha-trypsin inhibitor (ITI) family. Since GP120 showed no bikunin sequence, and chondroitinase treatment and alkaline treatment of GP120 did not affect its molecular weight, we concluded that GP120 was not a complex with bikunin. We designated GP120 as IHRP (ITI heavy chain-related protein).

Determination of carboxyl-terminal residue and disulfide bonds of MACIF (CD59), a glycosyl-phosphatidylinositol-anchored membrane protein

MACIF (CD59) is a glycosyl-phosphatidylinositol (GPI)-anchored membrane glycoprotein which inhibits the formation of membrane attack complex of human complement. MACIF prepared from human erythrocyte membranes was digested with pronase. When the digest was subjected to two-phase partition with butanol and 0.1 N HCl, the carboxyl-terminal peptide was recovered in the butanol phase because of the attachment of the highly hydrophobic GPI. The amino acid sequence of the peptide was determined to be Asn72 at its amino-terminus and up to Glu76, while the presence of Asn77 was ambiguous. To allow unequivocal determination of the carboxyl-terminus, a soluble form of MACIF was prepared from human urine on a large scale. The carboxyl-terminal peptide from the soluble form was prepared by tryptic digestion followed by reversed-phase HPLC. The sequence and composition of the peptide unequivocally revealed Asn77 as the carboxyl-terminus. The pattern of disulfide bonds of MACIF was also determined with the membrane form as well as the soluble form. Cystine-containing peptides were prepared by chymotryptic and tryptic digestion, purified by HPLC, and their amino acid sequences were determined. The results indicated that disulfide bonds were formed at Cys3-Cys26, Cys6-Cys13, Cys19-Cys39, Cys45-Cys63 (or 64), and Cys63 (or 64)-Cys69.

Tetrasomy 8 in acute myelomonocytic leukemia developing after a gastric cancer operation

A 70 year-old-Japanese man underwent gastrectomy for early gastric cancer with preoperative hypocellular marrow. Three weeks later, acute myelomonocytic leukemia developed with tetrasomy for chromosome 8 (48,XY,+8,+8). The patient died of leukemia on the 33rd postoperative day. Whether or not the operation triggered the leukemia remains unknown.

Molecular cloning and characterization of MACIF, an inhibitor of membrane channel formation of complement

Human erythrocytes contain a membrane protein, MACIF, which inhibits the formation of a membrane attack complex (MAC) of complement. We have cloned and sequenced the complementary DNA of MACIF messenger RNA. The amino acid sequence predicted from its nucleotide sequence consists of 128 amino acids. The amino-terminal 25 residues may correspond to a signal peptide. The carboxy-terminal sequence confirmed that MACIF is a glycosylphosphatidylinositol (GPI)-anchored protein. The amino acid sequence of MACIF was partially determined by established techniques for protein chemistry and the resultant sequence was consistent with that predicted from the nucleotide sequence. The results of sequence analyses also suggested that asparagine at the 18th position was N-glycosylated. When mRNA obtained from the MACIF cDNA clone with SP6 RNA polymerase was microinjected into Xenopus oocytes, the oocytes synthesized a product which exhibited MACIF activity and reacted with anti-MACIF antibody. Comparison of the predicted sequence revealed significant homology with mouse Ly-6 antigens.

Changes in QT interval during exercise testing in patients with VVI pacemakers

The changes in QT intervals were studied in nine patients with normal sinus node function who had VVI pacemakers. Though PP intervals uniformly shortened during exercise, the change in QaT* intervals during exercise was variable. The correlation between PP and QaT intervals varied from case to case. A good correlation was found in only two cases (r = +0.816 or +0.897); a fair correlation was found in four cases (r = +0.672, +0.615, +0.615, or -0.669) and in the remaining three, the correlation was poor (r = +0.494, +0.467 or -0.424). In patients who are candidates for VTI pacemaker implantation, changes in QaT intervals should be assessed during exercise stress testing to determine if the intervals shorten during exercise or not.