External quality assessment survey for SARS-CoV-2 nucleic acid amplification tests in clinical laboratories in Tokyo, 2021

INTRODUCTION

Nucleic acid amplification tests (NAATs) play a pivotal role in clinical laboratories for diagnosing COVID-19. This study aimed to elucidate the accuracy of these tests.

METHODS

In 2021, an external quality assessment of NAATs for SARS-CoV-2 was conducted in 47 laboratories in Tokyo, Japan. In open testing, where the laboratories knew that the samples were intended for the survey, a simulated nasopharyngeal swab suspension sample was used, featuring a positive sample A with a viral concentration of 50 copies/μL, positive sample B with 5 copies/μL, and a negative sample. Laboratories employing real-time RT-PCR were required to report cycle threshold (Ct) values. In blind testing, where the samples were processed as normal test samples, a positive sample C with 50 copies/μL was prepared using a simulated saliva sample.

RESULTS

Of the 47 laboratories, 41 were engaged in open testing. For sample A, all 41 laboratories yielded positive results, whereas for sample B, 36 laboratories reported positive results, 3 laboratories reported "test decision pending", 1 laboratory reported "suspected positive", and 1 laboratory did not respond. All 41 laboratories correctly identified the negative samples as negative. The mean Ct values were 32.2 for sample A and 35.2 for sample B. In the blind test, six laboratories received samples. Sample C was identified as positive by five laboratories and negative by one laboratory.

CONCLUSIONS

The nature of the specimen, specifically the saliva, may have influenced the blind test outcomes. The identified issues must be meticulously investigated and rectified to ensure accurate results.

Genetic Characteristics of the Virus Detected in the First Mpox Imported Case in Tokyo, Japan

Mpox, caused by the mpox virus (MPXV), produces symptoms similar to those of smallpox when transmitted to humans. Since 1970, this disease has been endemic, particularly in Africa. However, since May 2022, the number of patients without a history of travel to endemic areas has increased rapidly globally. Under these circumstances, in July 2022, two different real-time PCR methods were used on specimens brought to the Tokyo Metropolitan Institute of Public Health. MPXV was detected in the skin samples, and it was inferred that the virus was a West African strain. Furthermore, a more detailed analysis of the genetic characteristics of the detected MPXV using next-generation sequencing revealed that the MPXV detected in Tokyo was strain B.1, which corresponds to the same strain that is prevalent in Europe and the USA. This suggests that mpox reported for the first time in Japan was imported and related to outbreaks in Europe and the USA. Therefore, it is necessary to continue monitoring outbreaks in Japan in conjunction with global epidemics.

Multisource surveillance conducted by the Tokyo Metropolitan Government during the Tokyo 2020 Olympic and Paralympic Games

The Tokyo 2020 Olympic and Paralympic Games (the Games) were held from 23 July to 5 September 2021 in Tokyo, Japan, after a 1-year delay due to the coronavirus disease (COVID-19) pandemic. The Tokyo Metropolitan Government was responsible for monitoring and responding to infectious disease outbreaks other than COVID-19 during the Games. A multisource surveillance system was used from 1 July to 12 September 2021 for the early detection and rapid response to infectious diseases. This included routine notifiable disease surveillance, sentinel surveillance, syndromic surveillance, cluster surveillance, ambulance transfer surveillance and the Tokyo Infectious Alert system. Daily reports were disseminated summarizing the data collected from the multisource surveillance system. No case of infectious disease under the Tokyo Metropolitan Government system required a response during the Games. The multisource surveillance was useful for providing intelligence during the Games and, if required, could contribute to the early detection and rapid response to outbreaks during other mass gatherings. The system could be improved to overcome the challenges implied by the findings of this multisource surveillance.

Melanin-producing medullary thyroid carcinoma with transformation to melanoma: A case report

Only one case of melanoma arising from melanin-producing medullary thyroid carcinoma (MTC) has been reported previously. In the present study, a second such case was reported and compared with the previous one. The patient was an 86-year-old male who presented with a right anterior neck mass. Ultrasound revealed a nodule measuring 49x48x40 mm in the right lobe of the thyroid. The levels of serum calcitonin (2,298 pg/ml) and carcinoembryonic antigen (CEA; 27.0 ng/ml) were markedly elevated. Aspiration cytology revealed suspected malignant anaplastic thyroid carcinoma and total thyroidectomy without neck nodal dissection was performed. On gross observation, the nodule was well encapsulated, soft, solid and black. Light microscopy indicated that the nodule was composed mainly of large, occasionally huge, pleomorphic cells with a solid or alveolar growth pattern. On immunohistochemistry, these cells were positive for melan-A and S-100 protein, and negative for thyroid transcription factor 1, calcitonin, chromogranin A and CEA. In the subcapsular area, melanin-producing MTC was intimately intermingled with the pleomorphic cells. No primary site of the melanoma was detectable in other organs. At three years after surgery, the patient died due to metastasis of the melanoma to the brain. The previously reported case had no detectable recurrence or distant metastasis up to 11 years after surgery. In comparison with that case, the present case had a similar morphology but the outcome was poorer. Thus, the prognosis of melanoma that transforms from MTC appears to remain uncertain.

Effectiveness and cost-effectiveness of influenza vaccination for elderly people

For elderly people who have low incidence of influenza, calculation of credible vaccine effectiveness (VE) sometimes becomes difficult. Currently, VE for elderly people is insufficient to ascertain the precise efficacy specifically. Cost-effectiveness of influenza vaccination of elderly people is discussed widely in terms of topics and areas. This report describes research results demonstrating influenza vaccination effectiveness among elderly people based on recent findings. Newly available influenza vaccination for elderly people appears to be cost-effective compared with that of trivalent inactiveted influenza vaccine. Overall, for all influenza virus types, it remains unclear whether influenza vaccination shows high VE. A decreasing effect of repeated vaccination was confirmed partially by test negative design and a serological study of cohorts. However, some studies have found no such decreasing effect. Measurement of VE and subsequent analysis of the cost-effectiveness of influenza vaccination for elderly people requires long-term monitoring using serological studies and test negative design.

A study of quality assessment in SARS-CoV-2 pathogen nucleic acid amplification tests performance; from the results of external quality assessment survey of clinical laboratories in the Tokyo Metropolitan Government external quality assessment program in 2020

Introduction

The Tokyo Metropolitan Government (TMG) conducted an external quality assessment (EQA) survey of pathogen nucleic acid amplification tests (NAATs) as a TMG EQA program for SARS-CoV-2 for clinical laboratories in Tokyo.

Methods

We diluted and prepared a standard product manufactured by Company A to about 2,500 copies/mL to make a positive control and distribute it with a negative control. The participants reported the use of the NAATs methods for SARS-CoV-2, the name of the real-time RT-PCR kit, the name of the detection device, the target gene(s), nucleic acid extraction kit, Threshold Cycle value in the case of RT-PCR and the Threshold time value and Differential calculation value in the case of Loop-Mediated Isothermal Amplification (LAMP) method.

Results

As a result, 17 laboratories using fully automated equipment and 34 laboratories using the RT-PCR method reported generally appropriate results in this EQA survey. On the other hand, among the laboratories that adopted the LAMP method, there were a plurality of laboratories that judged positive samples to be negative.

Conclusion

The false negative result is considered to be due to the fact that the amount of virus genome contained in the quality control reagent used this time was below the detection limit of the LAMP method combined with the rapid extraction reagent for influenza virus. On the other hand, false positive results are considered to be due to the non-specific reaction of the NAATs. The EQA program must be continued for the proper implementation of the pathogen NAATs.

Higher Incidence of Syphilis among Patients with HIV Infection: Population Study using Surveillance Data of Tokyo, Japan

In Japan, the reported cases of syphilis have been increasing since 2011 especially in large cities such as Tokyo. The objective of this study was to evaluate the risk of HIV infection for syphilis co-infection on the population of Tokyo, Japan. We analyzed data of syphilis cases obtained from additional surveillance by the Tokyo Metropolitan Government in 2018, including those with human immunodeficiency virus (HIV) infection as well as data of HIV/acquired immunodeficiency syndrome (AIDS) cases during 1985-2017. We calculated the incidence of symptomatic syphilis cases among HIV-infected or non-HIV-infected individuals. Similarly, we calculated the incidence of syphilis, including asymptomatic cases, among each population. The relative risk of HIV infection for syphilis, including or excluding asymptomatic syphilis cases, was estimated. The relative risk was calculated by dividing the incidence of syphilis in the HIV-infected population by that in the non-HIV-infected population. Of the 1,775 syphilis cases reported in 2018, 172 cases were infected with HIV, 575 cases were uninfected, and the remainder were either unknown or not reported. The cumulative number of HIV/AIDS cases during 1985-2017 in Tokyo was 9,629; among them, 172 were co-infected with syphilis. The relative risk of HIV infection for syphilis was estimated as 423.29 if asymptomatic syphilis cases were included, and 372.37 if they were excluded. These results showed an extremely high risk of HIV infection. Since many syphilis cases have unknown or unreported HIV infection status, reduction of these cases might contribute to more reliable estimation of HIV infection risk.

Evaluating Apple Inc Mobility Trend Data Related to the COVID-19 Outbreak in Japan: Statistical Analysis

Background

In Japan, as a countermeasure against the COVID-19 outbreak, both the national and local governments issued voluntary restrictions against going out from residences at the end of March 2020 in preference to the lockdowns instituted in European and North American countries. The effect of such measures can be studied with mobility data, such as data which is generated by counting the number of requests made to Apple Maps for directions in select countries/regions, sub-regions, and cities.

Objective

We investigate the associations of mobility data provided by Apple Inc and an estimate an an effective reproduction number R(t).

Methods

We regressed R(t) on a polynomial function of daily Apple data, estimated using the whole period, and analyzed subperiods delimited by March 10, 2020.

Results

In the estimation results, R(t) was 1.72 when voluntary restrictions against going out ceased and mobility reverted to a normal level. However, the critical level of reducing R(t) to <1 was obtained at 89.3% of normal mobility.

Conclusions

We demonstrated that Apple mobility data are useful for short-term prediction of R(t). The results indicate that the number of trips should decrease by 10% until herd immunity is achieved and that higher voluntary restrictions against going out might not be necessary for avoiding a re-emergence of the outbreak.

Effects of voluntary event cancellation and school closure as countermeasures against COVID-19 outbreak in Japan

BACKGROUND

To control the COVID-19 outbreak in Japan, sports and entertainment events were canceled and schools were closed throughout Japan from February 26 through March 19. That policy has been designated as voluntary event cancellation and school closure (VECSC).

OBJECT

This study assesses VECSC effectiveness based on predicted outcomes.

METHODS

A simple susceptible-infected-recovered model was applied to data of patients with symptoms in Japan during January 14 through March 26. The respective reproduction numbers for periods before VECSC (R0), during VECSC (Re), and after VECSC (Ra) were estimated.

RESULTS

Results suggest R0 before VECSC as 2.534 [2.449, 2.598], Re during VECSC as 1.077 [0.948, 1.228], and Ra after VECSC as 4.455 [3.615, 5.255].

DISCUSSION AND CONCLUSION

Results demonstrated that VECSC can reduce COVID-19 infectiousness considerably, but after VECSC, the value of the reproduction number rose to exceed 4.0.

Risk factors affecting the failure to complete treatment for patients with latent tuberculosis infection in Tokyo, Japan

OBJECTIVE

The treatment completion rate for all latent tuberculosis infection (LTBI) patients in Tokyo was 83.6% in 2014: somewhat lower than the targeted goal of 85%. This study examines the association between risk factors and LTBI patients' failure to complete treatment.

METHODS

We collected data related to the treatment of LTBI patients who were reported to public health centers in Tokyo from January 2014 through December 2014. Data included potential risk factors affecting treatment, treatment results, and patient characteristics. We used Fisher's exact test to evaluate risk factors affecting failure to complete treatment. The failure rate was defined as the incompletion rate of treatment.

RESULTS

Of 1060 notified cases, 877 had completed treatment; 116 had not completed treatment. Of these 116 cases, failure to complete treatment in 52 cases was attributable to side effects of anti-tuberculosis drugs. Reasons other than side effects were given for 64 cases. Another 67 cases could not be followed up. In all, 941 cases were analyzed, excluding cases lost to follow-up and cases for which patients had not completed treatment because of anti-tuberculosis drug side effects. Failure rates among foreign-born patients (26.9%) were significantly much higher than those among Japan-born patients (3.9%). Statistical tests indicated no presumed potential risk factor as significant. However, "no supporter for foreign-born LTBI patients" was marginally significant.

CONCLUSION

Only "no supporter for foreign-born LTBI patients" was found to be marginally significant. More data must be accumulated to assess the risk factors affecting LTBI treatment.

Determinants of Vaccination Coverage for the Second Dose of Measles-Rubella Vaccine in Tokyo, Japan

In Japan, some measles outbreaks were initiated by a tourist from oversea and foreign workers recently. Moreover, rubella outbreak emerged since July 2018 mainly in the South Kanto, and the outbreak is currently ongoing in 2019. It is important to maintain a high measles-rubella combined vaccine (MR) coverage for measles-rubella control. Vaccination coverage for the second dose of MR (MR2) is 90.8% in Tokyo in 2016, which was the third worst among all prefectures in Japan. The purpose of this study was to clarify determinant factors of vaccination coverage for MR2 in Tokyo. Data were obtained for 49 wards and cities in Tokyo in 2016. We regressed vaccination coverage of MR2 on the times of notification by mail, the proportion of households receiving welfare payments, and the proportion of non-Japanese elementary school students. In addition to the simplest specification, five factors were included separately as explanatory variables: the proportion of public health nurses; the ratio of the number of pediatric medical facilities to the number of preschool and elementary school children; the moving-in rate; the proportion of households with a single parent; and the proportion of households with husband and wife both working. Results show that a high proportion of households receiving welfare payments, notification by two or more letters, and moving-in rate or a lower proportion of non-Japanese elementary school students improve coverage. In conclusion, the health authorities can exert efforts to reduce burden of time spent for vaccination and provide sufficient information to improve coverage.

Syndromic surveillance using ambulance transfer data in Tokyo, Japan

Bioterrorism attacks become more probable when important high-profile international or political events are held, such as G7 summit meetings or mass gathering events including Olympic and Paralympic games and FIFA World Cup tournaments. Outbreaks of infectious disease and widespread incidents of food poisoning are also public health concerns at such times. In Japan, the Tokyo Metropolitan Government operates Ambulance Transfer Syndromic Surveillance (ATSS), which can help monitor such incidents. The present study presents and assesses the ATSS framework. During the study period of October 2017 through November 2018, we monitored 33 areas for symptoms of 9 categories: vomiting/nausea, dizziness, palpitation, unconsciousness, breathing disorder, fever, spasm/paralysis, collapse/weakness, and bloody emesis/nasal hemorrhage. Among all symptoms, we found 9929 low-level aberrations, 2537 medium-level aberrations, and 577 high-level aberrations, with respective frequencies of 9.2%, 2.3%, and 0.5%. Of those, Tokyo Metropolitan Institute of Public Health reported the information to Tokyo Metropolitan Government 28 times during the period. Of the 28 identified clusters, Tokyo Metropolitan Government judged the necessity for investigating 7. All of those were investigated at hospitals by the jurisdictional public health center. Because ATSS covers almost the entire Tokyo metropolitan area, with about 13.8 million residents, it is definitely the largest syndromic surveillance in the world.

Association of influenza outbreak in each nursery school and community in a ward in Tokyo, Japan

In nursery schools, influenza outbreaks have occurred every year. However, influenza characteristics of its diffusion among nursery schools, within each nursery school, and among classes of different ages in nursery schools remains unclear. This paper presents an examination of these matters using the Nursery School Absenteeism Surveillance System (NSASSy). All nursery schools in ward A in Tokyo introduced to the NSASSy in 2015. The study period was November 2015 through March 2016. The data of influenza patients were extracted from NSASSy. We examined four definitions of 'starting date of community outbreak' (SDCO) of influenza: 1) the first recorded day of influenza patients (SDCO1), 2) the last day of influenza patients recorded for two consecutive days (SDCO2), 3) three consecutive days (SDCO3), and 4) four consecutive days (SDCO4). We evaluated those four definitions by duration of the initial case at each nursery school from SDCO and evaluated the proportion of nursery schools at which the initial case occurred before SDCO. The average durations of initial cases at respective nursery schools from SDCO1-4 were 40.3, 26.3, 23.1 and 13.3 days. The respective proportions of nursery schools at which the initial case occurred before SDCO1-4 were 3.1%, 6.4%, 9.4% and 40.6%. Results demonstrate that SDCO3 is an appropriate definition of SDCO. Robustness checks for other areas, seasons, and population size constitute the next challenge for research in this area.

Enhancing Preparedness against Rubella at the Workplace: Proactive Prevention Efforts by the Tokyo Metropolitan Government

In the 2012-2013 rubella epidemic in Japan, most transmissions in Tokyo occurred at workplaces, especially among men aged 20-49 years. This tendency was likely related to previous rubella immunization policies that prioritized female adolescents. Since 2015, the Tokyo Metropolitan Government has been promoting a project to prevent rubella and other infectious diseases in workplaces. Companies participate by choosing one or more of three options: (i) acquire fundamental understanding of infectious diseases, (ii) develop a Business Continuity Plan (BCP) for infectious diseases in the workplace, and (iii) increase rubella antibody prevalence in employees.Criteria for accomplishment are (i) at least 80% of employees complete the infectious disease training modules or (ii) produce a BCP and (iii) at least 90% of employees demonstrate the presence of antibodies at levels sufficient for preventing rubella. As of July 2018, 39.8% (n ＝ 90) of the 226 companies that began participating in 2015-2017 had met at least one accomplishment criteria (Option I, 42.7% of 192 companies; Option II, 19.3% of 140; and Option III, 17.0% of 53). The main project challenges were recruiting companies and following participating companies. Although early in its implementation, this project has made considerable contributions toward rubella elimination in Japan.

High-resolution imaging of coronary calcifications by intense low-energy fluoroscopic X-ray obtained from synchrotron radiation

Purpose: To obtain an intense monochromatic low-energy X-ray from synchrotron radiation (SR) and apply it to detect coronary calcifications.

Methods and Results: The SR beam was reflected with a silicon crystal to be expanded (150 mm in height and 80 mm in width) and to be monochromatized at an energy level of 37 keV. The X-ray was intermittently irradiated to obtain dynamic imaging of 30 images/s. Images were recorded by a digital fluorography system. The low-energy X-ray from SR sharply visualized calcification of coronary arteries, while conventional X-ray could not visualize coronary calcification.

Conclusion: The intense monochromatic low-energy X-ray from SR is sensitive, has high-resolution for imaging coronary calcification and may serve as a screening method for coronary artery disease.

Shedding of Rubella Virus among Infants with Congenital Rubella Syndrome Born in Tokyo, Japan, 2013-2014

Rubella is usually a mild illness, with febrile rash being its main symptom. However, serious consequences of rubella infection can result when the infection occurs during the early stages of pregnancy. After the occurrence of a rubella outbreak in Japan that was observed from 2012 to 2013, 45 infants were reportedly born with congenital rubella syndrome (CRS). We prospectively followed the 15 CRS cases reported in Tokyo to determine the virus shedding periods by using nested reverse transcriptase-polymerase chain reaction to detect rubella virus genes. Throast swabs were used for virus detection. The virus shedding period was measured from birth until the time when the sample last tested positive followed by 2 consecutive negative samples. Kaplan-Meier method was used to estimate the proportion of cases remaining positive for rubella virus genes over time. The proportion of CRS cases shedding virus dropped steadily after birth, dropping to 33.8% at 6 months and 16.9% at 12 months. Our findings also suggested that the earlier the mother's onset of rubella during pregnancy, the longer the infant remained positive. Based on our findings, we believe that infants with CRS should be monitored for rubella virus shedding until 1 year of age.

Increase in Primary and Secondary Syphilis Notifications in Men in Tokyo, 2007-2013

The number of notified syphilis cases in Tokyo has more than doubled in recent years. The number of reported primary and secondary syphilis cases increased from 108 cases (0.8 per 100,000 population) in 2007 to 245 cases in 2013 (1.9 per 100,000 population). During this period, the majority of cases was male (905/1,024), and the recent increase among primary and secondary syphilis cases was attributed to the increase among males (90/108 [83%] cases in 2007 to 218/245 [89%] cases in 2013); men aged 20-49 years contributed most to the increase, with those aged 30-34 years having the highest notification rate in 2013. Male-to-male transmission was the primary route of infection reported, and men who have sex with men (MSM) accounted for nearly 80% of male cases in 2013. Syphilis appears to be reemerging in Tokyo, and reducing the risk of acquiring syphilis among MSM aged 20-49 years should be a public health priority in Tokyo.

Enhanced Surveillance for the Sports Festival in Tokyo 2013: Preparation for the Tokyo 2020 Olympic and Paralympic Games

Enhanced surveillance was conducted during the Sports Festival in Tokyo 2013 (September 28-October 14, 2013) for early detection of outbreaks of infectious diseases and other health emergencies. Through this enhanced surveillance, 15 cases were found that required additional gathering of information outside the routine process of creating/evaluating the Daily Report. However, none of these was assessed as critical. Through the enhanced surveillance, we structured a framework that allows for earlier response when detecting aberrations. It includes the role of the Tokyo Metropolitan Government in communications and contacts with relevant parties such as public health centers, as well as in monitoring of surveillance data. However, some issues need to be further considered toward the Tokyo 2020 Olympic and Paralympic Games, such as establishing the criteria for additional response steps, increasing the number of participating bodies in syndromic surveillance, and strengthening of cooperation with related departments, including those for crisis management assuming potential biological/chemical terrorism.

Radioactive iodine (RAI) therapy for distantly metastatic differentiated thyroid cancer (DTC) in juvenile versus adult patients

In general, juvenile differentiated thyroid carcinoma (DTC) demonstrate indolent characteristics and favorable prognosis are observed in comparison with many other carcinomas. However, recurrence is frequent, necessitating additional treatment, including radioactive iodine (RAI) therapy. In this report, the probability of recurrence, prognostic factors, treatment, and outcomes in both juvenile- and adult-onset DTC were analyzed and compared. At our institution, a total of 1552 DTC patients underwent thyroidectomy and/or lymph node dissection. The patients included 23 in their teens, 118 in their twenties, and 1412 in their thirties or older. The risk factors for distant metastases for DTC were male gender, follicular carcinoma, size of the PTC primary tumor, cervical lymph node metastases from PTC, and the presence of more than two distant metastatic foci. Patients with the highest risk underwent RAI ablation in line with institutional guidelines. Although the overall outcome in our juvenile patients was excellent, during follow-up, 4 (17.4%) of the 23 patients developed recurrent disease: 91.3% achieved complete remission, 4.35% partial remission, and 4.35% stable disease, with no disease-related deaths. Among the 118 patients in their twenties to thirties, 1 (0.8%) experienced progressive disease and disease-related death. A younger age at diagnosis and less radical primary surgery without subsequent RAI ablation are factors strongly predictive of distant metastases in patients with juvenile-onset DTC. To reduce the rate of relapse and improve surveillance for recurrent disease, total thyroidectomy followed by RAI appears to be the most beneficial initial treatment for patients with high- and intermediate-risk juvenile DTC.

Epidemiological characteristics of rubella and congenital rubella syndrome in the 2012-2013 epidemics in Tokyo, Japan

A large rubella outbreak has been observed since June 2012 in Tokyo, Japan, and a rapid increase in the number of congenital rubella syndrome (CRS) cases have also been reported in Japan since October 2012. All the clinically diagnosed and laboratory-confirmed rubella cases reported in Tokyo from January 2012 to December 2013 and all the laboratory-confirmed CRS cases from January 2012 to March 2014 were analyzed. In total, 4,116 rubella cases were reported in Tokyo. Of these, 77.2% (n=3,176) were male; the highest number of cases occurred in males aged 35-39 years and in females aged 20-24 years. Complications included arthralgia/arthritis (19.4%), thrombocytopenic purpura (0.5%), hepatic dysfunction (0.3%), and encephalitis (0.1%). The circulating rubella virus in Tokyo was genotype 2B. The most possible site of transmission was the workplace. Because of the rubella epidemic, 16 CRS cases were reported in Tokyo from March 2013 to February 2014. Domestic infection with rubella was proven for all mothers of 16 cases. This situation suggests that Japan is still working to achieve rubella elimination.

Thyroglobulin suppresses thyroid-specific gene expression in cultures of normal but not neoplastic human thyroid follicular cells

CONTEXT

It was shown in the rat thyroid that thyroglobulin (Tg) stored in the follicular lumen is a potent regulator of thyroid-specific gene expression to maintain the function of individual follicles. However, the actions of Tg as a regulatory molecule in human thyroid have not been studied.

OBJECTIVE

Our objective was to determine the effect of Tg on gene expression in normal and diseased human thyroid and to examine whether the proposed model of negative-feedback autocrine regulation of thyroid function by Tg is applicable in the human as well as the rat.

DESIGN

Primary cultures of human thyrocytes were established from normal thyroid, Graves' disease thyroid, adenomatous goiter, follicular adenoma, and papillary carcinoma tissues obtained during surgery. Cells were stimulated with physiologic (ie, follicular) concentrations of Tg, and mRNA and protein expression of genes involved in thyroid hormonogenesis were evaluated. The effects of Tg on thyroid-specific gene expression were also assessed in 2 human papillary carcinoma cell lines.

RESULTS

Transcript levels of genes participating in thyroid hormone biosynthesis were significantly reduced by Tg in thyrocyte cultures derived from normal and Graves' thyroid, but not in cultures derived from thyroid neoplasms and adenomatous goiter.

CONCLUSION

It was confirmed that Tg acts as a negative-feedback regulator of gene expression in human thyrocytes, suggesting that Tg signaling may constitute a common mechanism for maintaining thyroid homeostasis in species with follicular thyroid morphology. However, certain diseases of intrinsic thyroid overgrowth appear to be associated with an escape from the regulatory mechanism of Tg.

Biological differential diagnosis of follicular thyroid tumor and Hürthle cell tumor on the basis of telomere length and hTERT expression

BACKGROUND

The most difficult thyroid tumors to diagnose by histology are follicular carcinomas (FTCs) and Hürthle cell carcinomas (HCCs). Telomere alteration and human telomerase reverse transcriptase (hTERT) expression have been observed in most human cancers and are known to be a feature of malignancy. The purpose of this study was to clarify whether hTERT protein expression and telomere alteration could be applicable biological markers for distinguishing FTC from HCC.

METHODS

We investigated a total of 78 thyroid tumor cases, including 14 FTCs, 47 follicular adenomas (FTAs), 5 HCCs, and 12 Hürthle cell adenomas (HCAs). hTERT protein expression was examined by immunohistochemistry, and telomere length was determined by tissue quantitative fluorescence in situ hybridization.

RESULTS

Positivity for hTERT protein expression was observed in 86 % of FTCs and 49 % of FTAs. Telomeres in FTCs were significantly shorter than those in FTAs. All HCCs and HCAs (100 %) expressed hTERT protein. Telomeres in HCCs were significantly shorter than those in HCAs.

CONCLUSIONS

Our results suggest that hTERT protein expression and telomere shortening would be applicable as biological markers to distinguish FTC from FTA. Previous studies have suggested that follicular tumor and Hürthle cell tumor should be classified biologically as distinct tumors. All Hürthle cell tumors expressed hTERT protein and HCCs had markedly shortened telomeres, suggesting that follicular tumor and Hürthle cell tumor might be biologically distinct entities.

Therapeutic strategy for low-risk thyroid cancer in Kanaji Thyroid Hospital

It is well-known that differentiated thyroid carcinoma (DTC) has a generally indolent character and shows a favorable prognosis in comparison with many other carcinomas. The therapeutic strategy for patients with DTC in Japan has differed from that in Western countries. Total thyroidectomy followed by radioactive iodine (RAI) ablation has been standard in Western countries, whereas limited hemi-thyroidectomy and subtotal thyroidectomy has been extensively accepted in Japan. Papillary thyroid carcinoma (PTC) accounts for over 90% of all thyroid cancers in Japan. The majority of patients with PTC are categorized into a low-risk group on the basis of the recent risk-group classification schemes, and they show excellent outcomes. Several management guidelines for thyroid cancers have been published in Western countries. However, the optimal therapeutic options for PTC remain controversial, and high-level clinical evidence aimed at resolving these issues is lacking. Moreover, as socioeconomic differences in medical care exist, conventional policies for the treatment of PTC have differed between Japan and other countries. This review focuses on the special features of treatment in Japan for patients with low-risk DTC involving subtotal thyroidectomy without adjuvant therapies, rather than total thyroidectomy with RAI, with the aim of preserving quality of life. At our institution in Japan, we have had extensive experience with RAI treatment for high-risk DTC patients, and this represents a very rare situation. Here we introduce the therapeutic strategy for low-risk thyroid cancer in Japan, including the measures adopted at our institution.

[The 2011 measles outbreak in Tokyo. An analysis of surveillance data]

OBJECTIVES

The study was conducted with the intention of establishing a strategy to eliminate measles on the basis of an analysis of the epidemiological profile of measles cases reported in Tokyo during the year 2011.

METHODS

We investigated measles cases reported to the Tokyo Metropolitan Government in 2011, recorded as part of the National Epidemiological Surveillance of Infectious Diseases. Factors analyzed included age, vaccination status for each patient, cases for which records were discarded after laboratory confirmation, genotype of the measles virus and relationships between dates of specimen collection and results of polymerase chain reaction (PCR) and IgM antibody tests.

RESULTS

A total of 178 measles cases were reported in Tokyo during 2011, and the majority of cases (128, 71.9%) were reported during the peak period from epiweeks 13 to 24. The largest age group reported was one to four years of age (40, 22.5%) followed by groups of 20-29 and 30-39 years of age (both 34, 19.1%). Most cases were sporadic, with only six outbreaks occurring. Even then, the numbers of cases for each outbreak was less than five. More than half of the patients in all age groups, except for the 1-4-year-old group, had not been vaccinated or did not have a record of vaccination. Genotypes D4 and D9 of measles virus were detected in most cases. However, genotype D5, which had been circulating in Japan before 2008, was not detected.

CONCLUSION

Imported viruses were the cause of measles cases reported in Tokyo during 2011. The disease control was better than that in 2007 and 2008 because of the swift and appropriate responses to the occurrences. It is also possible that there has been an increase in the proportion of people with immunity to measles. Increasing the rate of immunization, performing effective surveillance, and confirming suspicious measles cases by using molecular methods are important for achieving the elimination of measles.

Amplification of the human epidermal growth factor receptor 2 gene in differentiated thyroid cancer correlates with telomere shortening

The human epidermal growth factor receptor 2 (HER2) proto-oncogene plays an important role in the development and progression of breast and gastric cancer. Monitoring of the HER2 status and treatment with trastuzumab was performed initially in breast cancer, and subsequently in gastric cancer. However, the HER2 status of thyroid cancer remains unexplored. Telomere alteration and telomerase activity have been observed in most human cancers and are known to be a feature of malignancy. The aims of this study were to clarify the HER2 status of thyroid cancer and to examine any correlations to various characteristics of malignancy. We investigated 69 cases of differentiated thyroid cancers with reference to: i) telomere length as measured using tissue quantitative fluorescence in situ hybridization (Q-FISH), ii) expression of human telomerase reverse transcriptase (hTERT) as determined by immunohistochemistry (IHC), and iii) overexpression of the HER2 protein as determined by IHC and amplification of the HER2 gene as determined by fluorescence in situ hybridization (FISH). The telomeres of thyroid cancers, especially follicular carcinomas, were significantly shorter compared to those of adjacent normal tissues. Positivity for hTERT expression and HER2 amplification were observed in approximately 70 and 22% of thyroid cancers, respectively. Our data demonstrated that telomeres in HER2-positive cancers were significantly shorter compared to those in HER2-negative cancers. These results suggest that highly malignant differentiated thyroid cancer can be detected by monitoring HER2 status and telomere shortening, and that trastuzumab therapy may be effective for refractory thyroid cancer.

[The possibility of outbreak control by real-time surveillance with PCR method perfomed immediately--a case study of hand foot and mouth disease outbreak in a day care facility for children]

OBJECT

We examined the relationship between syndromic surveillance and laboratory confirmation, at an early stage of an outbreak of hand foot and mouth disease and RS virus infection.

METHOD

We observed the epidemiological situation from a surveillance system at a day care facility for young children in Tokyo from one week before onset of the indicator until one month thereafter. For laboratory diagnosis, we collected a rectal swab or a nasal swab from one patient in the early stage of the outbreak.

RESULT

A total of 20 patients, comprising 12 1-year-old, 5 2-year-old and 3 3-year-old children, were found to have hand foot and mouth disease on August 1st, 2011. From a rectal swab from one HFMD patient, enterovirus genome was detected and identified as coxsackievirus type A6 (CA6) with PCR sequencing. The CA6 had 99% identity to CA6 (Genbank No AB663318) in the VP4 coding region. RS virus also was detected from a nasal swab.

DISCUSSION

The establishment of a surveillance system at day care facilities for children can monitor infectious diseases among young children promptly. Laboratory confirmation, even though from only one patient as shown in this study, can provide critical information regarding the causative agent of the outbreak. This method is easy to conduct and could be used for activating appropriate countermeasures.

CONCLUSION

We believe that the combination of the timeliness of a surveillance system at day care facility for children and the convenience of laboratory diagnosis of even one patient can detect the causative pathogen, and thus enable the activation of countermeasures before an outbreak become widespread.

[Relationship between BCG immunization coverage and the immunization delivery system in the Tama area of Tokyo]

PURPOSE

The BCG immunization has long been performed in Japan. Although the BCG immunization service is the responsibility of the municipality, the manner in which the BCG immunization is delivered differs from municipality to municipality. The purpose of this study was to clarify how the different manner of the BCG immunization delivery systems influenced the BCG immunization coverage.

METHODS

The study of BCG immunization coverage was conducted in the Tama area located in the western suburbs of Tokyo in 2004. The birth data and the immunization history by the age of 3 years were collected in the three-year-old health check-up from a total of 2,341 children residing in the Tama area. Based on the age at immunization for each child, the BCG immunization coverage was calculated according to the types of the BCG immunization delivery system. The immunization types were defined as follows; the BCG immunization given on the occasion of the mass health check-up (Group 1); the exclusive mass BCG immunization in a monthly service (Group 2); the exclusive mass BCG immunization in a bimonthly service (Group 3); the exclusive mass BCG immunization in services of fewer than every two months (Group 4); and the immunization given on an individual basis by a general practitioner (Group 5). A univariate analysis was performed to examine the relationship between the BCG immunization coverage by the age of 6 months and the difference among the BCG immunization delivery systems, followed by a multivariate regression analysis to adjust for the factors related to the demography, health care services and the socio-economic status of the municipalities.

RESULTS

Unadjusted odds ratios and adjusted odds ratios for BCG unimmunized children under the age of 6 months by the BCG immunization delivery manner groups were OR 1 reference, adj. OR 1 reference in Group 1; OR 1.42 CI 0.87-2.29, adj. OR 4.01 CI 2.24-7.11 in Group 2; OR 4.96 CI 3.66-6.82, adj. OR 15.59 CI 10.10-24.49 in Group 3;OR 18.60 CI 13.77-25.49, adj. OR 48.17 CI 29.62-79.75 in Group 4; and OR 4.24 CI 2.86-6.31, adj. OR 15.61 CI 9.05-27.26 in Group 5. The univariate analysis and multivariate regression analysis revealed an influence of the BCG immunization delivery manner on the BCG immunization coverage.

CONCLUSION

The choice of BCG immunization delivery manner is very important to raise the BCG immunization coverage. The BCG immunization given on the occasion of the mass health check-up and the high-frequent immunization service are thought to improve the BCG immunization coverage.

Low-dose dobutamine radionuclide ventriculography for prediction of myocardial viability: quantitative analysis of regional left ventricular function

BACKGROUND

It is important to distinguish viable myocardium from necrotic tissue in order to decide upon therapy in patients with ischemic heart disease.

HYPOTHESIS

We verified the hypothesis that quantitative analysis of regional left ventricular function using low-dose dobutamine radionuclide ventriculography (RNV) can sensitively predict myocardial viability and compared its usefulness with thallium-201 (201Tl) single-photon emission computed tomography (201Tl-SPECT).

METHODS

Radionuclide ventriculography at rest and during low-dose dobutamine infusion (5 micrograms/kg/min), 201Tl-SPECT, and coronary angiography were performed in 51 subjects with severe ischemia-related stenosis of coronary arteries and 3 subjects without coronary artery disease. 201Tl uptake was assessed as normal (control), low perfusion (LP), or defect. We compared the response of regional function to dobutamine with the regional 201Tl uptake. The accuracy of both methods for identifying viable myocardium was investigated in 17 patients who underwent successful coronary revascularization, with a resulting improvement in wall motion.

RESULTS

The increase in regional ejection fraction (delta r-EF) in response to dobutamine was significantly greater in the control (12 +/- 6%) and LP (16 +/- 11%) regions than in the defect (5 +/- 10%) regions. The increase in one-third regional ejection fraction (delta r-1/3EF) was also significantly higher in the control (14 +/- 7%) and LP (10 +/- 8%) regions than in the defect regions (5 +/- 6%). We defined myocardial viability as a delta r-EF > 5% or a delta r-1/3EF > 2%. The sensitivity and specificity of the delta r-EF for identification of myocardial viability were 91.4 and 55.5%, respectively. The sensitivity and specificity of the delta r-1/3EF were 91.4 and 66.6%, respectively; the corresponding values for 201Tl SPECT were 74.2 and 77.8%.

CONCLUSION

Low-dose dobutamine RNV with quantitative analysis of regional left ventricular function was more sensitive for identification of viable myocardium than 201Tl-SPECT.

[Variation in yield of needle scars with multipuncture BCG vaccination]

PURPOSE

BCG vaccination using the multipuncture percutaneous method has long been employed in Japan. The purpose of this study is to clarify whether the number of needle scars achieved the BCG vaccination differs with the vaccinating physician.

METHODS

A total of 218 babies who were vaccinated at the age of 4 months by different physicians at the Public Health Centres of Katsushika-Ward, Tokyo, were examined at the age of 3 years, in the three-year-old health check-up programme. The BCG vaccination with the multipuncture method generates 18 needle scars at a maximum. We examined each child for how many needle scars after BCG vaccination were visible, with reference to the vaccinating physician.

RESULTS

The mean number of the visible scars was 9.23 (SD 6.11), and significantly smaller (P < 0.01) than that for all 22 Wards (12.18 +/- 5.64) investigated with the same method. The mean number of needle scars of the babies in Katsushika Ward was the third smallest among the 22 Wards and significantly smaller (P < 0.05) than the national average as determined in the nationwide survey conducted in 2000. Significant differences were evident among the 7 physicians performing the vaccination, the best and second best means being 15.26 (SD3.62) and 14.59 (SD3.58) respectively, and significantly larger (P < 0.01) than the means for the 7 physicians. The worst mean was 3.43 (SD4.46), significantly smaller (P < 0.01) than the mean for the 7 physicians.

CONCLUSION

The mean number of needle scars after BCG vaccination of babies significantly differed with the 7 physicians in the present study. Poor technique was presumed responsible for small numbers of scars and technical training is therefore necessary in order to improve the BCG vaccination outcome.

Ets-1 is involved in transcriptional regulation of the chick inducible nitric oxide synthase gene in embryonic ventricular myocytes

In order to elucidate roles of Ets family of transcription factors in transcriptional activation of inducible nitric oxide synthase (iNOS) genes, we analyzed the chick iNOS gene expression in cultured chick embryonic ventricular myocytes (CEVM). Deletional analysis and site-directed mutagenesis demonstrated that both the Ets/PEA3 site (-221 to -216 bp) and the kappaB site (-101 to -93 bp) of the 5'-flanking region of the chick iNOS gene were involved in the maximal activation of the lipopolysaccharide (LPS)-induced expression of the reporter (luciferase) gene, although the proximal kappaB site played the more essential role. Electrophoretic mobility shift assay revealed that LPS augmented the nuclear protein bindings to the Ets/PEA3 as well as kappaB motifs. Ets-1, one of the Ets proteins, was suggested to be bound to the Ets/PEA3 oligonucleotide. By Northern blot analysis, LPS was shown to induce iNOS mRNA in CEVM, along with a preceding increase in the levels of c-ets-1 mRNA. Ets-1 may be involved in the iNOS gene transcription in CEVM, presumably through interacting with the NF-kappaB.

Hypertrophic cardiomyopathy with midventricular obstruction and apical aneurysm: a case report

A 71-year-old woman had hypertrophic cardiomyopathy associated with midventricular obstruction and an apical aneurysm in the left ventricle. She had had abnormal electrocardiograms for more than 30 years and for the past year had been suffering from occasional attacks of dizziness and low systemic blood pressure. Holter 24-h electrocardiographic monitoring revealed ventricular paroxysmal contractions (676/day) with nonsustained ventricular tachycardia. Doppler echocardiography revealed paradoxical jet flow from the apical aneurysm to the left ventricular outflow during early diastole. Magnetic resonance imaging depicted midventricular hypertrophy and a dyskinetic thin apical wall, which were confirmed by angiography. Coronary angiograms showed no narrowing of the major extramural coronary arteries, but there was compression of aberrant coronary arteries apparently feeding the hypertrophic portion of the left ventricular wall. Stress thallium-201 myocardial imaging showed a persistent severe defect in the left ventricular apex. A hemodynamic study revealed low cardiac output and an intraventricular pressure gradient (approximately 90 mmHg) between the left ventricular apical high-pressure chamber and the subaortic low-pressure chamber. The present case represents a rare combination of hypertrophic cardiomyopathy, midventricular obstruction, and an apical aneurysm in an elderly woman. Myocardial ischemia may have played an important role in the genesis of the apical aneurysm.

Left ventricular relaxation abnormality is detectable by analysis of the relaxation time constant in patients with atrial fibrillation

Left ventricular (LV) contractility is constantly changing during atrial fibrillation (AF), which is dependent on the force-interval relationships. However, no information has been available on LV relaxation in patients with both AF and impaired LV systolic function. LV pressure was measured with a catheter-tipped micromanometer and the time constant of isovolumic LV pressure decline (tau(bf)) was calculated with best exponential fitting from more than 10 consecutive beats. Patients with AF (5 with mitral valvular disease, 6 with idiopathic dilated cardiomyopathy, and 1 with no underlying disease) were subdivided into 2 groups: group A, with ejection fraction (EF) <0.5 (n=7); and group B, with EF > or =0.5 (n=5). Linear correlation coefficients (r) between tau and RR2, RR2/RR1, LV peak systolic pressure (peak LVP) were calculated. Although tau did not show a discrepancy between the 2 groups, tau(bf) correlated better with RR2/RR1 only in the group A patients. The relation between tau and peak LVP showed a good correlation with a steep slope (R, Deltatau/Deltapeak LVP) only in the group A patients (accentuated afterload-dependence). R was significantly different between the 2 groups. Thus, a beat-to-beat analysis of tau may be a practical and feasible way for detecting LV relaxation abnormality in patients with AF.

Cloning of hypoxia-inducible factor 1alpha cDNA from chick embryonic ventricular myocytes

Hypoxia-inducible factor 1 (HIF-1) is composed of HIF-1alpha and arylhydrocarbon nuclear receptor translocator (ARNT), which belong to the basic-helix-loop-helix-Per/ARNT/Sim (bHLH-PAS) family of transcription factors. HIF plays key roles in oxygen homeostasis and embryonic cardiovascular development. In this study, we have cloned cDNAs encoding the chick HIF-1alpha from cultured embryonic ventricular myocytes (CEVM) and then examined its expression in various embryonic tissues. The deduced amino acid sequence of the chick HIF-1alpha cDNA showed 79% identity with that of the human HIF-1alpha cDNA. In contrast, sequence homology between the chick HIF-1alpha and endothelial PAS protein 1 (EPAS1), another member of the bHLH-PAS proteins, was only low (49%). HIF-1alpha mRNA was expressed abundantly in CEVM, but scarcely in the liver, which was quite different from expression pattern of EPAS1 mRNA. These data suggest that HIF-1alpha may be involved in embryonic cardiovascular development. HIF-1alpha and EPAS1 may play distinct roles during developmental stages.

Expression of genes encoding vascular endothelial growth factor and its Flk-1 receptor in the chick embryonic heart

Vascular endothelial growth factor (VEGF) is known to play an essential role in embryonic vascular development. The heart is one of the main organs that produce VEGF, but it is still unknown how expression of VEGF gene is regulated in embryonic cardiac myocytes. Thus, we cloned cDNAs encoding VEGF and its receptor (a KDR/flk-1 or Quek1 homologue) from cultured 10-day-old chick embryonic ventricular myocytes (CEVM). Reverse transcription-polymerase chain reaction revealed that the chick VEGF mRNAs consisted of at least four different species corresponding to the isoforms of 190, 166, 146 and 122 amino acids. In the embryonic heart and CEVM, the isoforms of 166 and 122 amino acids were dominant. Northern blot analysis detected an abundance of VEGF mRNA in both the embryonic heart and CEVM, even at the basal state. The levels of VEGF mRNA in CEVM were significantly augmented by forskolin (100 microM), or phorbol 12-myristate, 13-acetate (200 nM) in a time-dependent manner in CEVM. In contrast, the basal levels of VEGF mRNA were attenuated by genistein (100 microM), but not by H89 (100 microM) or bisindolylmaleimide (75 microM). Northern blot analysis also detected the chick flk-1 mRNA in abundance in the embryonic heart, and to a much lesser extent in CEVM. The expression levels of VEGF and flk-1 mRNA species were continuously high in the 6, 8 and 10-day-old chick embryonic hearts. In the 10-day-old embryonic hearts, in situ hybridization confirmed that mRNA encoding VEGF was mainly expressed in ventricular myocytes. In contrast, the flk-1 mRNA was detected in the microvascular endothelial cells, and to a lesser extent in the ventricular myocytes. These data suggest that VEGF is produced in embryonic ventricular myocytes, even at the basal state, and that the levels of VEGF mRNA may be differently regulated by various protein kinases. VEGF produced by the chick embryonic heart may play important roles in embryonic cardiovascular development by acting on surrounding endothelial cells and, possibly, on ventricular myocytes themselves.

Hemodynamic and thermal responses to a 30-minute constant-workload aerobic exercise in middle- or old-aged patients with cardiovascular diseases

The aim of the present investigation was to compare the hemodynamic and thermal responses to a 30-min aerobic exercise between middle- or old-aged patients with normal left ventricular function and those with left ventricular dysfunction. Constant-load sitting ergometer exercise of approximately 90% of the subject's oxygen uptake (VO2) at the anaerobic threshold for 30 min was conducted in 21 patients with left ventricular dysfunction (61+/-10 years, left ventricular ejection fraction (LVEF) 35+/-7%) and 24 patients with normal left ventricular function (59+/-9 years, LVEF 71+/-7%). Heart rate (HR), blood pressure, deep temperatures in the forehead and thigh, and forearm skin blood flow (SkBF) were measured every minute, and cardiac output (CO) and stroke volume (SV) were determined every 10 min with the dye-dilution technique during the exercise. Patients of both groups exhibited a progressive elevation in each temperature and an increase in SkBF during the exercise. Although the VO2 and CO remained stable, almost the same magnitude of decrease in SV as increase in HR was seen after the 10th min of exercise in both groups. The magnitude of the decrease in SV was greater in old-aged than middle-aged patients with left ventricular dysfunction. Thus, the downward drift in SV during a 30-min constant-load aerobic exercise might not be influenced by left ventricular function, but intensified by aging in patients with left ventricular dysfunction.

Lipopolysaccharide augments expression and secretion of vascular endothelial growth factor in rat ventricular myocytes

Vascular endothelial growth factor (VEGF), also known as vascular permeability factor, is highly expressed in the myocardium under various stimuli including hypoxia and ischemia. On the other hand, lipopolysaccharide (LPS) causes systemic inflammatory response syndrome (SIRS), which consists of systemic pathophysiological changes related to vascular hyperpermeability. To test the hypothesis that VEGF is one of the important mediators of SIRS, we examined effects of LPS on the VEGF expression and secretion in cultured neonatal rat ventricular myocytes. LPS (10 microg/ml) rapidly (within 1 h) augmented the levels of VEGF mRNA in these cells. Pharmacological inhibition of nucleic factor-kappaB or tyrosine kinases did not affect the LPS-induced augmentation of VEGF mRNA expression, while these treatments markedly suppressed the up-regulation of inducible nitric oxide synthase (iNOS) expression by LPS. The VEGF concentrations in the conditioned media were also significantly increased by the LPS treatment of 6 h. In conclusion, LPS augments VEGF expression and secretion in rat ventricular myocytes, suggesting that VEGF may be involved in pathogenesis of SIRS. LPS may induce VEGF mRNA through the signaling pathways that are distinct from those responsible for the iNOS induction.

High-resolution imaging of coronary calcifications by intense low-energy fluoroscopic X-ray obtained from synchrotron radiation

PURPOSE

To obtain an intense monochromatic low-energy X-ray from synchrotron radiation (SR) and apply it to detect coronary calcifications.

METHODS AND RESULTS

The SR beam was reflected with a silicon crystal to be expanded (150 mm in height and 80 mm in width) and to be monochromatized at an energy level of 37 keV. The X-ray was intermittently irradiated to obtain dynamic imaging of 30 images/s. Images were recorded by a digital fluorography system. The low-energy X-ray from SR sharply visualized calcification of coronary arteries, while conventional X-ray could not visualize coronary calcification.

CONCLUSION

The intense monochromatic low-energy X-ray from SR is sensitive, has high-resolution for imaging coronary calcification and may serve as a screening method for coronary artery disease.

Biological reactions in the heart: what should we do in 'cardiology'?

Humankind is on a similar evolutionary process to animals. Biological reactions in the human heart will be reviewed, and consideration will be made about what can be done in cardiology, from the viewpoints of basic, clinical and community medicine. Functional reactions of the heart to acute loading (exercise, etc) comprise myocardial contractility, preload, pump function and peripheral factors, and are mobilized step by step in that order, to maintain normal functioning. Morphological reactions to chronic loading (hypertension etc) comprise hypertrophy and dilatation, which are caused by mechanical and nonmechanical factors, but may not always be mobilized to maintain normal functioning. Various neurohumoral factors take part in the mechanisms, and modifications, of these reactions. They act in a complex manner according to the biological conditions, and may not always act to maintain normal functioning. The biological reactions in the heart (ie, Basic Cardiology) should not be interpreted as having purpose; that is, putting a value on humankind, although medical treatment (Clinical Cardiology) and the solution of health problems in the community (Community Cardiology) should be done from this viewpoint.

An adult case with an abnormal right ventricular structure causing intraventricular pressure gradient and a history of aphthous stomatitis and thrombophlebitis

We report a 50-year-old man with a right ventricular structure causing an intraventricular pressure gradient. He had been diagnosed as vasculo-Behçet with a history of aphthous stomatitis and thrombophlebitis. He had also been suffering from atrial flutter and mild right-side heart failure. Echocardiography showed that there was an abnormal structure attached to the right ventricular free wall and protruding into the cavity, and that it caused the pressure gradient estimated to be approximately 19 mmHg. Chest X-ray computed tomography demonstrated that the structure was partially calcified. Magnetic resonance imaging depicted the structure separating the right ventricle into two chambers. Angiographic study revealed a markedly enlarged right atrium and a filling defect at the mid-portion of the right ventricle, which divided the right ventricular cavity into two parts. Hemodynamic study showed a slightly elevated right atrial pressure (mean 7 mmHg) and a peak-to-peak intraventricular pressure difference of 18 mmHg in the right ventricle. The diastolic pressure tracing of the right ventricular low pressure chamber showed a 'dip and plateau' pattern. Although the pathological features of the abnormal right ventricular structure in this case were not fully clarified, abnormal muscle bundle and/or endocardial fibrosis, which were reported to be associated with Behçet's disease, may have contributed to its generation.