Factors associated with COVID-19 booster vaccine hesitancy: a nationwide, cross-sectional survey in Japan

OBJECTIVES

COVID-19 vaccine hesitancy/fatigue is increasing as the pandemic enters the endemic phase. The present study aimed to explore current perceptions about COVID-19 booster vaccination among the Japanese public.

STUDY DESIGN

This was a cross-sectional study.

METHODS

This cross-sectional study used data from the Japan COVID-19 and Society Internet Survey conducted in September 2021 and September 2022. The public's perceptions of COVID-19 vaccination and factors associated with COVID-19 booster vaccine hesitancy were analyzed.

RESULTS

In total, 56,735 respondents were included. In the Japan COVID-19 and Society Internet Survey 2021, 75.1% of the participants (21,126/28,118) had completed the primary vaccination series. In the 2022 survey, 74.1% of the respondents (21,216/28,617) completed the primary series of vaccination with booster doses. The proportion of fear toward COVID-19 and obtaining information about COVID-19 has decreased from 2021 to 2022. Factors independently associated with booster vaccine hesitancy were young age (range: 18-29 years; adjusted odds ratio [aOR]: 6.56), history of COVID-19 (aOR: 1.82), distrust of the Japanese government's COVID-19 prevention measures (aOR: 1.55), lack of confidence in COVID-19 vaccine efficacy (aOR: 1.30), lack of confidence in COVID-19 vaccine safety (aOR: 1.62), low reliance on the COVID-19 vaccine (aOR: 1.92), and belief in COVID-19 conspiracy theories (aOR: 1.77).

CONCLUSIONS

Providing clear and trustworthy information is critically important, especially targeted and tailored messages for the young generation, to promoting COVID-19 booster vaccination. Policymakers should therefore develop consistent and transparent communication strategies and the ability to respond promptly and flexibly to mitigate the negative impact of COVID-19 on the public while preparing for the next pandemic.

Dental Pain and Worsened Socioeconomic Conditions Due to the COVID-19 Pandemic

The coronavirus disease 2019 (COVID-19) pandemic has led to economic contraction and significant restrictions on society. The shock to the economy could lead to a deterioration of physical health outcomes, including dental health. The present study investigated the association between worsened socioeconomic conditions due to the COVID-19 pandemic and dental pain in Japan. The mediating effects of psychological distress and oral health-related behaviors were also evaluated. Cross-sectional data from the Japan COVID-19 and Society Internet Survey conducted from August to September 2020 (n = 25,482; age range, 15-79 y) were analyzed. Multivariable logistic regression models were fitted to evaluate the independent associations of household income reduction, work reduction, and job loss due to the COVID-19 pandemic with dental pain within a month. Dental pain was reported by 9.8%. Household income reduction, work reduction, and job loss were independently associated with dental pain after adjusting for confounders (odds ratios: 1.42 [95% confidence interval (CI), 1.28-1.57], 1.58 [95% CI, 1.41-1.76], 2.17 [95% CI, 1.64-2.88], respectively). The association related to household income reduction was mediated by psychological distress, postponing dental visits, toothbrushing behavior, and between-meals eating behavior by 21.3% (95% CI, 14.0-31.6), 12.4% (95% CI, 7.2-19.6), 1.5% (95% CI, -0.01 to 4.5), and 9.3% (95% CI, 5.4-15.2), respectively. Our findings showed that worsened socioeconomic conditions due to the COVID-19 pandemic deteriorated dental health. Policies that protect income and job loss may reduce dental health problems after the pandemic.

Hospital volume and five-year survival after cancer surgery in 2007-2011 in Osaka, Japan

Background

The relationship between hospital volume (HV) and patient outcome is well-known evidence, and hospital volume is widely used as a quality indicator. In Japan, however, few studies are available on the associations between HV and survival after cancer surgery. This study aimed at examining the association between HV and longitudinal survival after surgeries of major cancer sites.

Methods

This is a retrospective observational study. Using the Osaka Cancer Registry database, we identified patients who were diagnosed as major sites of cancer (esophageal, gastric, colorectal, pancreatic, lung, breast, and uterus cancer) between 2007 and 2011, and undergone surgeries in Osaka. To define the quartiles of HV (high, medium, low, and very low-volume hospitals), we ranked hospitals by annual surgical volume, sorted patients in descending order of HV, and assigned them into four equal-sized groups. The study outcome was five-year survival from the diagnosis. We analyzed the associations between hospital volume and survival among eligible patients aged between 15 and 84 years old, using Cox proportional hazard models. In the models, we adjusted for characteristics of patient and treatment received by the patients.

Results

A sample of 86,867 patients were analyzed. The mortality hazards of patients treated at very low-volume hospitals were 1.4 - 2.1 times higher than that of patients treated at high-volume hospital in all selected cancers. However, absolute differences (percent points) in adjusted survival rates between high- and very low-volume hospitals were varied by cancer site: esophagus (24.2), stomach (14.9), colorectum (11.5), pancreas (9.2), lung (10.8), breast (2.4), and uterus (3.3).

Conclusions

Very low-volume hospitals showed the poorest patient survival after cancer resections. Healthcare quality assessment at lower-volume hospitals and referrals to higher-volume hospitals are potential measures to improve survival of cancer patients.

Key messages

Patients treated at lower-volume hospitals had a higher mortality risk than those treated at higher-volume hospitals. Healthcare quality assessments and effective referrals of high-risk patients are potential interventions to improve patient survival.

Synovial mesenchymal stem cells promote healing after meniscal repair in microminipigs

OBJECTIVE

The induction of synovial tissue to the meniscal lesion is crucial for meniscal healing. Synovial Mesenchymal stem cells (MSCs) are an attractive cell source because of their high proliferative and chondrogenic potentials. We examined whether transplantation of synovial MSCs promoted healing after meniscal repair of extended longitudinal tear of avascular area in a microminipig model.

DESIGN

Longitudinal tear lesion was made in medial menisci and sutured in both knees, and then a synovial MSC suspension was administered for 10 min only in unilateral knee. The sutured meniscus was evaluated morphologically and biomechanically at 2, 4, and 12 weeks. The behavior of transplanted MSCs was also examined.

RESULTS

The meniscal healing at 12 weeks was significantly better in the MSC group than in the control group; macroscopically, histologically and by T1rho mapping analysis. Transmission electron microscopic analysis demonstrated that the meniscus lesion was occupied by dense collagen fibrils only in the MSC group. Biomechanical analysis revealed that the tensile strength to failure of the meniscus higher in the MSC group than in the control group in each microminipig. Synovial tissue covered better along the superficial layer from the outer zone into the lesion of the meniscus in the MSC group at 2 and 4 weeks in each microminipig. Synovial MSCs labeled with ferucarbotran were detected in the meniscus lesion and adjacent synovium by MRI at 2 weeks.

CONCLUSION

Transplantation of synovial MSCs promoted healing after meniscal repair with induction of synovium into the longitudinal tear in the avascular zone of meniscus in pigs.

Tobacco smoking and the risk of subsequent primary cancer among cancer survivors: a retrospective cohort study

BACKGROUND

Smoking is a well-known risk factor for cancer; however, there is little evidence as to whether the smoking status of cancer survivors has any risk for subsequent primary cancer (SPC) incidence, regardless of the first cancer sites.

PATIENTS AND METHODS

In total, 29,795 eligible patients with a first cancer between 1985 and 2004 were examined for SPC until the end of 2006, using a record linkage between hospital-based and population-based cancer registries. The association between smoking at the time of the first cancer diagnosis and three SPC groups (i.e. specific SPC, smoking-related SPCs, and all SPCs) was calculated by Poisson regression.

RESULTS

Ever smokers had 59% and 102% higher risk for all SPCs and smoking-related SPCs, respectively, than never smokers. Cancer survivors who had recently stopped smoking had 18% and 26% less risk, respectively, for these SPCs than those who smoked at the diagnosis. We also found that, compared with those who had never smoked, cancer survivors who had ever smoked had a significantly elevated risk of oral/pharyngeal, esophageal, stomach, lung, and hematological SPCs, regardless of the first cancer sites.

CONCLUSIONS

These findings indicate that smoking increases not only the first cancer but also a second or SPC. Moreover, the results from recent quitters versus current smokers suggest that smoking cessation may decrease the risk for SPC, especially for smoking-related SPCs in cancer survivors. Preventive measures are necessary to reduce not only SPC incidence but also tobacco use.

Radiofrequency heating and magnetically induced displacement of dental magnetic attachments during 3.0 T MRI

OBJECTIVE

The aim of this study was to estimate the risk of injury from dental magnetic attachments due to their radiofrequency (RF) heating and magnetically induced displacement during 3.0 T MRI.

METHODS

To examine the magnetic attachments, we adopted the American Society for Testing and Materials F2182-02a and F2052-06 standards in two MRI systems (Achieva 3.0 T Nova Dual; Philips, Tokyo, Japan, and Signa HDxt 3.0 T; GE Healthcare, Milwaukee, WI). The temperature change was measured in a cylindrical keeper (GIGAUSS D600; GC, Tokyo, Japan) with coping of the casting alloy and a keeper with a dental implant at the maximum specific absorption rate (SAR) for 20 min. To measure the magnetically induced displacement force, three sizes of keepers (GIGAUSS D400, D600 and D1000) were used in deflection angle tests conducted at the point of the maximum magnetic field strength.

RESULTS

Temperature elevations of both coping and implant were higher in the Signa system than in the Achieva system. The highest temperature changes in the keeper with implant and keeper with coping were 0.6 °C and 0.8 °C in the Signa system, respectively. The temperature increase did not exceed 1.0 °C at any location. The deflection angle (α) was not measurable because it exceeded 90°. GIGAUSS D400 required an extra 3.0 g load to constrain the deflection angle to less than 45°; GIGAUSS D600 and D1000 required 5.0 and 9.0 g loads, respectively.

CONCLUSIONS

Dental magnetic attachments pose no risk due to RF heating and magnetically induced displacement at 3.0 T MRI. However, it is necessary to confirm that these keepers are securely attached to the prosthesis before imaging.

Esophageal fibrovascular polyp removed by cervical esophagotomy

We report a case of esophageal fibrovascular polyp (FVP) removed by cervical esophagotomy. The patient was a 74-year-old man in whom an intraesophageal mass was detected by a chest CT examination during a complete medical check-up. An upper gastrointestinal series showed a large, pedunculated, cervical esophageal mass for which our preoperative diagnosis was a FVP. We studied its features, as well as removal procedures in 45 patients in the literature. Most patients had marked symptoms, but ours had no complaints, and so this case may be a rare one. Various removal procedures were reported, but thoracotomy and esophagectomy are considered to be the inappropriate procedures since FVP is a benign disorder.

Effect of atorvastatin on microRNA 221 / 222 expression in endothelial progenitor cells obtained from patients with coronary artery disease

BACKGROUND

Endothelial progenitor cells (EPCs) play an important role in the maintenance of vascular integrity. Lipid lowering therapy (LLT) with statins may contribute to biologically relevant activities including the proliferation of endothelial cells. The physiological role of microRNA (miR)-221/222, a newly discovered class of small RNA, is closely linked to the proliferation of endothelial cells. We therefore investigated whether LLT with statins might affect miR-221/222 expression in EPCs obtained from patients with coronary artery disease (CAD).

MATERIALS AND METHODS

This study included 44 patients with stable CAD and 22 subjects without CAD (non-CAD). Patients with CAD were randomized to 12 months of LLT with atorvastatin (10 mg day(-1)) or pravastatin (10 mg day(-1)). EPCs were obtained from peripheral blood at baseline and after 12 months of statin therapy. Levels of miR-221/222 in EPCs were measured by real-time RT-PCR.

RESULTS

Levels of miR-221/222 were significantly higher in the CAD group than in the non-CAD group (P < 0.01). Levels of miR-221/222 were weakly negatively correlated with EPC number in the CAD group. After 12 months of therapy, changes in lipid profiles were greater in the atorvastatin group than in the pravastatin group. LLT with atorvastatin markedly increased EPC numbers and decreased miR-221/222 levels (all P < 0.05), whereas LLT with pravastatin did not change EPC numbers or miR-221/222 levels.

CONCLUSIONS

This study demonstrates that LLT with atorvastatin increases EPC numbers and decreases miR-221/222 levels in patients with CAD, possibly contributing to the beneficial effects of LLT with atorvastatin in this disorder.

Characterization of carotid atherosclerosis and detection of soft plaque with use of black-blood MR imaging

BACKGROUND AND PURPOSE

In the treatment of carotid atherosclerosis, the rate of stenosis and characteristics of plaque should be assessed to diagnose vulnerable plaques that increase the risk for cerebral infarction. We performed carotid black-blood (BB) MR imaging to diagnose plaque components and assess plaque hardness based on MR signals.

MATERIALS AND METHODS

Three images of BB-MR imaging per plaque were obtained from 70 consecutive patients who underwent carotid endarterectomy (CEA) to generate T1- and T2-weighted images. To evaluate the relative signal intensity (rSI) of plaque components and the relationship between histologic findings and symptoms, we prepared sections at 2-mm intervals from 34 intact plaques. We then calculated the relative overall signal intensity (roSI) of 70 plaques to assess the relationship between MR signal intensity and plaque hardness and symptoms.

RESULTS

The characteristics of rSI values on T1- and T2-weighted images of fibrous cap (FC), fibrosis, calcification, myxomatous tissue, lipid core (LC) with intraplaque hemorrhage (IPH), and LC without IPH differed. Symptomatic plaques were associated with FC disruption (P < .001) and LC with IPH (P < .05). The roSI on T1-weighted images was significantly higher for soft than nonsoft plaques. When the roSI cutoff value was set at 1.25 (mean of the roSI), soft plaques were diagnosed with 79.4% sensitivity and 84.4% specificity. The roSI was also significantly higher for symptomatic than for asymptomatic plaques. Soft and nonsoft plaques as well as symptomatic and asymptomatic plaques did not significantly differ on T2-weighted images.

CONCLUSION

BB-MR imaging can diagnose plaque components and predict plaque hardness. This procedure provides useful information for planning therapeutic strategies of carotid atherosclerosis.

Lymphangiosarcoma in a cat

This report describes a 5-year-old female cat with lymphangiosarcoma arising within the dermis and subcutis of the caudal mammary region. The mass presented as a large, poorly demarcated and fluctuant swelling with bruising of the overlying skin. Histopathologically, the dermis and subcutis in the affected region were diffusely oedematous, haemorrhagic, and infiltrated by plump spindle cells that formed irregular vascular clefts and cavernous channels. Neoplastic cells were aligned in one or more layers along oedematous collagenous trabeculae. The vascular clefts and channels contained only a few or no erythrocytes. The neoplastic cells had moderate to marked nuclear pleomorphism and prominent nucleoli. Lymphocytes and plasma cells were scattered throughout the neoplasm and the adjacent soft tissues. Immunohistochemical labelling revealed the neoplastic cells to express vimentin, factor VIII-related antigen and the lymphatic endothelial cell marker PROX-1, but the cells did not express cytokeratin. The nuclei of many neoplastic cells expressed the proliferation marker Ki67. These histopathological and immunohistochemical findings confirmed the diagnosis of lymphangiosarcoma. This is the first report describing the usefulness of expression of PROX-1 for differentiating between angiosarcoma of lymphatic and vascular origin in cats.

[Penetrating right ventricular trauma by stab injury; report of a case]

A 52-year-old woman, who had attempted to commit suicide with a kitchen knife, was admitted. Upon arrival, conscious level was II-30 and blood pressure was 76/46 mmHg. The knife with a blade 20 cm long penetrated the thorax from the 7th left intercostal space beside sternum toward the heart and synchronously moved with pulsation of the heart. The chest X-ray showed the left hemothorax and a computed tomography (CT) revealed the tip of the knife reached the right ventricle. After draining the pleural effusion from the left thorax, the median sternotomy and pericardiotomy were made. The knife was shown to be stuck in right ventricle as it grazed the left anterior descending artery and the right posterior descending artery through pericardium from the apex. The ST segments in II, III, aVF and chests leads were elevated in the preoperative electrocardiography (ECG), but any damage was not recognized in coronary arteries. Under the total bypass on extracorporeal circulation, the knife was removed. The wound at the right ventricle reached about 12 cm length from the apex to the inferior wall. Fortunately, papillary muscles, chorda, septum in the right ventricle and also the left lung were not injured. The wound of the right ventricle was closed with reinforced using felt-strips. The postoperative course was uneventful. This case suggested that the most important factor for survival in cardiac trauma would be to make the hemodynamics stable with the urgent treatment just after arrival and to perform the surgical repair immediately.

Abdominal stapled side-to-end anastomosis (Baker type) in low and high anterior resection: experiences and results in 69 consecutive patients at a regional general hospital in Japan

OBJECTIVE

The technique of transanally introducing a circular stapled device to accomplish colorectal anastomoses has been widely used. However, the widespread popularity of this technique may have created the potential of anal sphincter injury during transanal insertion of the anastomosing stapler. Thus, to avoid the risk of anal sphincter injury during anal manipulation, we have been performing an abdominal approach, namely abdominal stapled side-to-end anastomosis (ASSEA) using a Purstring and premium curved EEA stapler in low and high anterior resection. This study will present our experience and results of consecutive resections.

METHODS

ASSEA following a resection of the rectum and sigmoid colon for carcinomas was consecutively performed between October 1998 and May 2002. Age, sex, pre-operative anal function, the TNM classification by the UICC rules, operative methods, postoperative morbidity, mortality, anal function and bowel frequency were evaluated.

RESULTS

Sixty-nine consecutive patients underwent a resection of the rectum and sigmoid colon with ASSEA. There were three (4.3%) clinical anastomotic leakages in the cases studied. Anastomoses that were located above the peritoneal reflection leaked in one (2.5%) of 40 cases, while anastomoses below the peritoneal reflection leaked in two (6.9%) of 29 cases. A diverting stoma was performed in five (17%) of the 29 cases with low anastomosis. Postoperative anal function was stable without soiling or faecal leakage and bowel frequency two months after surgery was less than four times in all 61 patients. There was no postoperative mortality related to the anastomosis.

CONCLUSIONS

Abdominal stapled side-to-end anastomosis (Baker type) was found to be a safe and relatively easy method in both low and high anterior resection in association with a good quality of life.

Nitrogen removal from water containing high nitrate nitrogen in a paddy field (wetland)

Nowadays, it has become very common to find in Japan that nitrate nitrogen concentrations are very high in spring water and in well water where the land use of a watershed is agricultural. We have often observed around 50 mg/L of nitrate nitrogen in the spring water where we live. Crops produced in those fields are mainly vegetables such as celery, cabbage, lettuce, carrots, and so on. Green tea is also popular in Japan. In order to produce good quality green tea, farmers apply a great amount of nitrogen fertilizer. This amount can reach up to 1,000 kg/ha in some areas, although the average application amounts to 628 kg/ha in Japan. As a result, ground water that is rich in nitrate flows into the river, which results in a high nitrogen concentration in river water and ground water. Further, this causes a low pH in river water in some tributary rivers in Japan, though this kind of case is very rare. We knew from field tests that if water contained a high nitrogen concentration and was introduced into paddy fields, high nitrogen removal would be performed. This paper presents the outline and results of a system on how to remove nitrogen using paddy fields (wetlands). Further, this paper presents the evaluated results of the removal quantity at the watershed level.

[A case of primary HIV infection with oral candidiasis not diagnosed by western blot]

Seroconversion to human immunodeficiency virus(HIV) associated with an illness characterized by fever, sore throat, and lymphadenopathy, sometimes with rash, diarrhea, and vomiting. Leukopenia and liver dysfunction also can occur in some patients. The antibody response associated with HIV infection is directed against a variety of viral proteins. Western blot analysis(WB) is used currently for determining HIV-1 infection. A 47-year-old man whose wife was infected with HIV was found to have contracted primary HIV infection. His first HIV antibody examination 4 weeks after speculated exposure was negative by particle agglutination(PA) method and WB. Approximately 2 weeks later he experienced fever, general fatigue, oral candidiasis. His second laboratory examination showed positive PA and indeterminate WB tests, an HIV-RNA PCR of 4.4 x 10(5) copies/ml, 223 CD4+ lymphocytes/microliter, and liver dysfunction. Two weeks later, all of his symptoms and the abnormal lab data had improved with antifungal therapy alone and no anti-HIV therapy. Subsequently, it took 16 more weeks before HIV infection could be diagnosed by WB. It is necessary to adopt an appropriate HIV-1 PCR method to shorten the diagnostic window in primary HIV infection.

Multiple actin-related proteins of Saccharomyces cerevisiae are present in the nucleus

An increasing number of actin-related proteins (Arps), which share the basal structure with skeletal actin but possess distinct functions, have been found in a wide variety of organisms. Individual Arps of Saccharomyces cerevisiae were classified into Arps 1-10 based on the relatedness of their sequences and functions, where Arp1 is the most similar to actin, and Arp10 is the least similar. While Arps 1-3 and their orthologs in other organisms are localized exclusively in the cytoplasm, Arp4 (also known as Act3) is localized in the nucleus and is involved in transcriptional regulation. Here we examined the more divergent Arps for possible nuclear functions. We show that Arps 5-9 are localized in the nucleus, but Arp10 is not. The nuclear export signals identified in actin are well conserved in the cytoplasmic Arps, Arps 1-3, but less conserved in the nuclear Arps. Gel filtration chromatography experiments show that the nuclear Arps are larger than monomer in size and thus are present in multi-protein complexes. Since nuclear protein complexes containing Arps are found to be responsible for histone acetylation and chromatin remodeling, it is suggested that most of the divergent Arps are involved in the !transcriptional regulation through chromatin modulation.

[Actual conditions of occupational health administration of small-scale enterprises in Japan: (II). Occupational health controls for hazardous and musculo-skeletally stressful working factors]

In order to clarify the actual condition of occupational health management for hazardous and musculo-skeletally stressful work factors in small-scale enterprises (SSEs) in Japan, a questionnaire survey was conducted in an area near Osaka city. The hazardous work factors examined were dust, organic solvents, lead, specified chemical substances, anoxia, noise, hand-arm vibration, ionizing radiation, high and low temperatures, and high air pressure. The musculo-skeletally stressful work factors examined were VDT work, prolonged standing, unnatural postures, handling of heavy weights, and stress on neck, shoulders and arms. The number of SSEs that replied to the questionnaire was 765 (recovery rate: 69.3%). Enterprises with noise, dust, hand-arm vibration and organic solvents numbered 14.0%, 10.7%, 6.9% and 6.4%, respectively, and those with other hazardous factors numbered less than 3%. Special medical examinations and working environment measurements for hazardous factors were conducted in 0.0% to 26.7% and 0.0% to 13.3%, respectively, of the enterprises. Working environment controls were conducted in 0.0% to 40.2%. Enterprises with prolonged standing and VDT work, were 42.0% and 35.8%, whereas those with other stressful factors were approximately 30%. Special medical examinations for musculo-skeletally stressful factors were conducted in 3.0% to 5.1% of the enterprises, and work controls were conducted in 20.4% to 25.3%. Non execution of the special medical examinations and working environment measurements were mainly due to "lack of knowledge of the law (19.7% and 30.2%)" and "lack of time to perform (16.0% and 23.3%)". Non execution of the controls for the hazardous work factors was due to "lack of knowledge as to how to control (9.0%)", "high costs (7.4%)", "lack of time to perform (6.4%)" and "absence of a suitable adviser (5.9%)". Non execution of the controls for stressful work factors was due to "lack of knowledge as to how to control (15.6%)" and "lack of time to perform (10.2%)". Consequently, as a result of the survey, it was suggested that it is necessary to enlighten the employers of SEEs as to the importance of occupational health controls. It is also necessary to propose low-cost, feasible control methods.

Transperitoneal drainage for a large cystic degeneration after regression of an intra-abdominal desmoid tumor

A new technique is described for treating a large cystic degeneration after regression of an intra-abdominal desmoid tumors in patients with familial adenomatous polyposis. A cysto-peritoneal shunt is made for the relief of large cystic degeneration by creating a channel between the mesenteric cyst and the peritoneal cavity by means of a silicone tube to facilitate transperitoneal drainage.

Percutaneous ethanol injection for hepatocellular carcinoma originating in the caudate lobe

BACKGROUND/AIMS

Hepatocellular carcinoma originating in the caudate lobe is rare and the treatments for caudate hepatocellular carcinoma were thought difficult, because of its unique location at hepatic resection, or because of complex arterial supply at transcatheter arterial embolization. Percutaneous ethanol injection is an effective treatment for small hepatocellular carcinoma. The aim of this study was to assess the efficacy of percutaneous ethanol injection for hepatocellular carcinoma originating in the caudate lobe.

METHODOLOGY

During the past 4 years, 7 patients with 7 hepatocellular carcinomas originating in the caudate lobe underwent percutaneous ethanol injection as a curative treatment. The outcomes of percutaneous ethanol injection and the survival of the 7 patients were evaluated.

RESULTS

Percutaneous ethanol injection was successfully carried out with no severe complications in all patients. During follow-up periods local recurrence was noticed in a patient, that was treated with percutaneous ethanol injection again. Four patients had recurrence in other parts of the liver, who were treated with percutaneous ethanol injection alone or percutaneous ethanol injection and transcatheter arterial embolization. Six patients were alive for 12-55 months after percutaneous ethanol injection and 1 patient died of hepatic failure 15 months after the procedure.

CONCLUSIONS

Percutaneous ethanol injection was a safe and effective treatment, and it would be an alternative therapy for hepatocellular carcinoma originating in the caudate lobe.

[Actual conditions of occupational health activities in small-scale enterprises in Japan: system for occupational health, health management and demands by small-scale enterprises]

In order to clarify the real conditions of occupational health services (OHS) in small-scale enterprises (SSEs) in Japan, we analyzed questionnaires recovered from 765 SSEs in the area of a city neighboring Osaka City (recovery rate, 69.3%). The SSEs included 358 SSEs with 1 to 4 workers (46.8% of total SSEs), 203 with 5 to 9 (26.5%), 163 with 10 to 29 (21.3%) and 41 with 30 to 49 (5.4%). The main types of businesses were manufacturing (374, 48.9% of total SSEs), wholesale/retail trade/restaurants (153, 20.0%), community, social and personal services (132, 17.3%) and construction (72, 9.4%). Health examinations were performed in 47.7% of SSEs. The reason for the lack of examinations were "shortage of time" (33.3% of SSEs lacking health examination) and "employees do not want to be examined" (28.1%). Some health promotion measures were conducted in 29.2% of SSEs. Health examination (59.0% of SSEs), health promotion (36.5%), measure of mental health (25.9%) and information service for employers and employees (25.5%) were demanded by SSEs as OHS. Financial subsidies and economical incentives were demanded by 46.4% and 28.8% of SSEs, respectively. Regional occupational health center in this area was poorly known among SSEs (8.2%), but health examination (48.4%), information service (37.5%), assessment of work method and advice to improve (19.8%) and environment measurement (12.4%) are demanded of the center by SSEs.

Granulocyte apheresis as a possible new approach in cancer therapy: A pilot study involving two cases

Patients with advanced cancer often develop immunodeficiency which may be associated with granulocytosis. The granulocytes have the potential to deplete cytotoxic T cells, resulting in accelerated tumor growth and metastasis. To study the elimination of excess granulocytes using granulocyte apheresis in patients with elevated granulocyte to lymphocyte ratios, 2 patients with recurrent metastatic tumors, were selected. Granulocyte apheresis was performed by extracorporeal vein-to-vein circulation with the G-1 granulocyte and monocyte/macrophage apheresis column filled with cellulose acetate beads, each 2 mm in diameter to adsorb granulocytes and monocytes/macrophages. The patients received 1 or 2 apheresis of 30 to 50 min duration per week, at a flow rate of 30-50 ml/min, with 15 sessions constituting one therapeutic course. Apheresis markedly reduced tumor size and prolonged patient survival time without causing any serious adverse events. The results of the present study suggest that granulocyte and monocyte/macrophage apheresis may be beneficial in patients with metastasizing tumors.

Tumor staging of pancreatic adenocarcinoma using early- and late-phase helical CT

OBJECTIVE

We compared early-phase CT with late-phase CT in the evaluation of pancreatic adenocarcinoma.

MATERIALS AND METHODS

Both early- and late-phase CT images of 25 pancreatic adenocarcinomas were compared with surgical-pathologic findings. We evaluated tumor detectability, tumor size, and local tumor invasion.

RESULTS

Tumor detectability was 96% on early-phase CT imaging and 64% on late-phase CT imaging (p < .01). Sensitivity for anterior serosal invasion, retroperitoneal invasion, and arterial invasion on early-phase CT exceeded sensitivity on late-phase CT (p < .05). However, specificity for all factors on early-phase CT was less than or equal to specificity on late-phase CT. The grade of local tumor invasion on early-phase CT achieved better agreement with the surgical-pathologic results than did late-phase CT, especially for tumor size and retroperitoneal invasion.

CONCLUSION

Early-phase CT was better than late-phase CT in revealing tumors, tumor size, and retroperitoneal invasion.

Significance of late diastolic potential preceding Purkinje potential in verapamil-sensitive idiopathic left ventricular tachycardia

BACKGROUND

Verapamil-sensitive idiopathic left ventricular tachycardia (VT) is due to reentry with an excitable gap. A late diastolic potential (LDP) is recorded during endocardial mapping of this VT, but its relation to the reentry circuit and significance in radiofrequency (RF) ablation remain to be elucidated.

METHODS AND RESULTS

Sixteen consecutive patients with this specific VT were studied (12 men and 4 women; mean age, 32 years). In all patients, sustained VT was induced and during left ventricular endocardial mapping, LDP preceding Purkinje potential (PP) was recorded at the basal (11 patients), middle (3 patients), or apical septum (2 patients). The area with LDP recording was confined to a small region (0.5 to 1.0 cm2) in each patient and was included in the area where PP was recorded (2 to 3 cm2). The relative activation times of LDP, PP, and local ventricular potential (V) at the LDP recording site to the onset of QRS complex were -50.4+/-18.9, -15.2+/-9.6, and 3.0+/-13.3 ms, respectively. The earliest ventricular activation site during VT was identified at the posteroapical septum and was more apical in the septum than the region with LDP in every patient. In 9 patients, VT entrainment was done by pacing from the right ventricular outflow tract while recording LDP. During entrainment, LDP was orthodromically captured, and as the pacing rate was increased, the LDP-to-PP interval was prolonged, whereas stimulus-to-LDP and PP-to-V interval were constant. In 3 patients, the pressure applied to the catheter tip at the LDP region resulted in conduction block between LDP and PP and in VT termination. RF energy application at the LDP recording site successfully eliminated VT.

CONCLUSIONS

LDP was suggested to represent the excitation at the entrance to the specialized area with a conduction delay in response to the increase in the rate within the critical slow conduction zone participating in the reentry circuit of this VT. LDP can be a useful marker for successful RF ablation for this VT.

Atrial ectopy originating from the posteroinferior atrium during radiofrequency catheter ablation of atrioventricular nodal reentrant tachycardia

Atrial ectopy sometimes appears during RF ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT). However, its origin, characteristics, and significance are still unclear. To examine these issues, we analyzed 67 consecutive patients with AVNRT (60 with slow-fast AVNRT and 7 with fast-slow AVNRT), which was successfully eliminated by RF ablation to the sites with a slow potential in 63 patients and with the earliest activations of retrograde slow pathway conduction in 4 patients. During successful RF ablation, junctional ectopy with the activation sequence showing H-A-V at the His-bundle region appeared in 52 patients (group A) and atrial ectopy with negative P waves in the inferior leads preceding the QRS and the activation sequence showing A-H-V at the His-bundle region appeared in 15 patients (group B). Atrial ectopy was associated with (10 patients) or without junctional ectopy (5 patients). Before RF ablation, retrograde slow pathway conduction induced during ventricular burst and/or extrastimulus pacing was more frequently demonstrated in group B than in group A (9/15 [60%] vs 1/52 [2%], P < 0.001). Successful ablation site in group A was distributed between the His-bundle region and coronary sinus ostium, while that in group B was confined mostly to the site anterior to the coronary sinus ostium. In group B, atrial ectopy also appeared in 21% of the unsuccessful RF ablations. In conclusion, atrial ectopy is relatively common during slow pathway ablation and observed in 8% of RF applications overall and 22% of RF applications that successfully eliminated inducible AVNRT. Atrial ectopy appears to be closely related to successful slow pathway ablation among patients with manifest retrograde slow pathway function.

Slow potential-guided radiofrequency catheter ablation in atrioventricular nodal reentrant tachycardia: characteristics of the potential associated with successful ablation

To examine the characteristics of Haïssaguerre's slow potential (SP) specific to effective catheter ablation of the slow pathway in AV nodal reentrant tachycardia, the properties of SP and its recording site were analyzed in 52 patients who underwent successful SP-guided ablation. The properties of SP included the ratio of the amplitude of SP to that of atrial potential (A)(SP/A), the SP duration, the interval between His-bundle potential (HP) and SP (HP-SP), the interval between A and SP (A-SP), the interval between SP and ventricular potential (V) (SP-V), and the ratio of A-SP to the interval between A and the V (A-SP/A-V). The SP recording site was determined by the ratio of the amplitude of A to that of V (A/V) and by the relative position of the ablation catheter on X ray (right anterior oblique projection), expressed as the ratio of the distance between the coronary sinus ostium and SP site to that between the coronary sinus ostium and HP recording site (relative SP position). Twenty-eight slow pathways were ablated with a single energy application, while the other 24 required applications > or = 2. In all successful applications, SP/A, SP duration, HP-SP, A-SP, SP-V, A-SP/A-V, A/V, and relative SP position were 51% +/- 25%, 28 +/- 5 ms, -11 +/- 9 ms, 57 +/- 25 ms, 68 +/- 13 ms, 46% +/- 9%, 15% +/- 13%, and 51% +/- 13%, respectively. A significant correlation was observed between the relative SP position and A-SP, and between the relative SP position and A-SP/A-V (r = 0.60 and 0.37, respectively), while it was not between the relative SP position and HP-SP, nor between the relative SP position and SP-V. When the characteristics of SP were comparatively analyzed between the effective and ineffective applications in 24 patients in whom applications > or = 2 were required, there was no difference observed in HP-SP, A-SP, SP-V, A-SP/A-V, and A/V. However, SP/A, SP duration, and the relative SP position in the effective applications were all greater than those in the ineffective ones (56% +/- 20% vs 35% +/- 18%, P < 0.001; 29 +/- 4 vs 26 +/- 5 ms, P < 0.01; and 52% +/- 15% vs 33% +/- 11%, P < 0.001, respectively). These results indicate that SP with an amplitude over a half of A amplitude and recorded at the mid-septum of the tricuspid annulus can be a marker for successful slow pathway ablation. Although the local atrial electrogram appears late as the SP recording site shifts to the lower position, the timing of SP relative to HP and V remained unchanged, suggesting that SP is independent of the local atrial activation.

[Workers' stress after Hanshin-Awaji earthquake in 1995--symptoms related to stress after 18 months]

Stress-related symptoms were investigated in workers living in the area hit by the Hanshin-Awaji earthquake. Questionnaires were distributed among taxi and truck drivers, longshoremen, workers in factories, hospitals and local government offices 18 months after the event. Nearly 40% of them, 3,015 answered. The multiple regressive analysis showed that the degree of housing damage was the factor most relevant to the symptoms. Although the symptoms decreased as time passed, the group with seriously damaged housing still complained of severe stress-related symptoms even 18 months after the event. Symptoms related to post traumatic stress disorder (PTSD) were observed in 48.0% in the male group with seriously damaged housing immediately after the quake. The figure was 34.2% of after 3 months and 12.6% after 18 months. 21.8%, 12.9% and 3.7%, respectively, were the figures in the male group with nil or slightly damaged housing. The number of workers who complained of the recurrence and worsening of chronic diseases peaked 3 months after the event and had not changed much even after 18 months. Workers also complained of anxiety over the loss of work, job pressure, overwork, difficulty of commuting to and from the area, danger at work, decline in income and changes of job location.

[Load on the low back of teachers in kindergartens]

In order to evaluate the load on the low back of teachers in kindergartens, basic activity and working posture were analyzed for four teachers by means of video recording. The trunk inclination angle (TIA) was also measured continuously during full workshifts for 12 kindergarten teachers by means of an inclination monitor. The kindergarten teachers spent 67% of the workshift on activities in contact with children, "indoor group childcare", "indoor free playing", "outdoor childcare", "preparation and clearing away" and "help and care", and did not take a recess during the workshift. They spent 36% of the workshift in three working postures with the load on the low back, "standing bent forward", "squatting" and "kneeling". Cumulative time at a TIA of 20 degrees or more represented 43% of the workshift. The frequency of trunk-lifting from severe bending forward (TIA > 45 degrees) was 95 times/hr on average. A comparison of the kindergarten teachers and nursery teachers in 4-5 year age classes showed that the time distributions of basic activities were generally similar to each other. Although the time distributions of working postures were also similar, time spent "standing bent forward", "squatting" and "kneeling" was longer in the kindergarten teachers than in the nursery teachers. Cumulative time at a TIA of 45 degrees or more was significantly longer in the kindergarten teachers. Although the frequency of trunklifting was not significantly different, the kindergarten teachers tended to lift their trunk more frequently. The present study found that the load on the low back was considerably great in the kindergarten teachers.

Effects of pilsicainide and propafenone on vagally induced atrial fibrillation: role of suppressant effect in conductivity

The effects of pilsicainide on vagally induced atrial fibrillation and on electrophysiological parameters were compared with those of propafenone in alpha-chloralose-anesthetized dogs. Conduction velocity, effective refractory period, wavelength, averaged atrial fibrillation cycle length and activation sequence in the right atrial free wall were determined before and after drug administration. Pilsicainide (2 mg/kg/5 min and 3 mg/kg/h)(n=10) or propafenone (2 mg/kg/15 min and 4 mg/kg/h)(n=10) was intravenously infused during stable atrial fibrillation sustaining > 30 min. Pilsicainide terminated atrial fibrillation in nine dogs, while propafenone did so in three (p < 0.01). After the drug, conduction velocity was suppressed more in the pilsicainide than in the propafenone group(p < 0.01). There was no difference in effective refractory period after drug between the two groups. Mean wavelength was prolonged from 46.0 to 70.4 mm in the pilsicainide group and from 45.0 to 110.8 mm in the propafenone (p < 0.01 vs. pilsicainide). Activation mapping during atrial fibrillation showed Type II or III atrial fibrillation as previously defined [Konings, K.T.S., Kirchhof, C.J.H.J., Smeets, J.R.L.M., Wellens, H.J.J., Penn, O.C., Allessie, M.A., 1994. High-density mapping of electrically induced atrial fibrillation in humans. Circulation. Vol. 89, pp. 511-521.] before the drug, and changed to Type I before atrial fibrillation termination. Thus, pilsicainide was more effective to terminate vagally induced atrial fibrillation than was propafenone despite a greater effect of propafenone than of pilsicainide on wavelength. In this canine atrial fibrillation model, the suppression of conduction velocity may play an important role in changing the activation pattern of atrial fibrillation and thus, terminating atrial fibrillation.

Transcatheter arterial chemoembolization through collateral arteries for hepatocellular carcinoma after arterial occlusion

PURPOSE

The purpose of this study was to evaluate the efficacy of transcatheter arterial chemoembolization (TACE) through collaterals after hepatic artery occlusion or severe stenosis in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

During the past three and one-half years, 19 of 167 patients with HCC showed hepatic artery occlusion or severe stenosis after repeated TACE, and 17 patients underwent TACE through collateral arteries. Types of collaterals, results, and effects of TACE through collaterals were evaluated.

RESULTS

Common collaterals were periportal collateral, intrahepatic anastomosis, and right inferior phrenic artery. TACE was successfully carried out through all detected collaterals in 40 of 49 TACE trials (82%). In eight of 49 TACE trials (16%), TACE through collaterals was partially carried out. The cumulative survival rates at the end of the first, second, third, forth and fifth year were 100%, 79%, 79%, 59% and 59%, respectively.

CONCLUSION

TACE through collateral arteries was able to be performed in most cases and will be an effective treatment to control HCC.

Desmoplastic response in biopsy specimens of early colorectal carcinoma is predictive of deep submucosal invasion

PURPOSE

The aim of this study was to evaluate the role of histopathology of biopsy specimens in predicting depth of infiltration in early colorectal carcinomas before treatment.

METHODS

Early colorectal carcinomas that had been resected surgically or endoscopically between 1984 and 1995 were analyzed. Histopathologic findings, including differentiation of adenocarcinoma and a desmoplastic response were investigated.

RESULTS

One hundred nine early colorectal carcinomas consisted of 73 lesions of carcinoma in situ, 13 submucosal carcinomas with minimum invasion, 8 lesions with moderate invasion, and 15 lesions with deep invasion. Of 73 carcinoma in situ lesions, 72 (approximately 99 percent) showed well-differentiated adenocarcinomas and no desmoplastic response. Twelve (92 percent) of 13 submucosal carcinomas with minimum invasion also revealed well-differentiated adenocarcinoma without a desmoplastic response. Sixty-three percent (5/8) of lesions with moderate invasion revealed well-differentiated adenocarcinoma. None of the lesions had a desmoplastic response. Among lesions with deep invasion, 73 percent (11/15) demonstrated moderately differentiated adenocarcinoma, and 11 lesions had a prominent desmoplastic response (73 percent; P < 0.01).

CONCLUSIONS

These results suggest that if histopathologic findings of biopsy specimens taken from them before treatment demonstrated adenocarcinoma associated with a desmoplastic response, the lesions had at least deep invasion carcinomas. These lesions should be resected surgically. Submucosal carcinomas with minimum invasion, which have no desmoplastic response, could be treated endoscopically.

Portal vein anomaly associated with deviation of the ligamentum teres to the right and malposition of the gallbladder

PURPOSE

To develop a complete clinical picture of a portal vein anomaly associated with a rightward-deviated ligamentum teres.

MATERIALS AND METHODS

Three hundred twenty-seven consecutive living donor candidates for partial liver transplantation were evaluated for hepatic vascular abnormalities with computed tomography supplemented with intraoperative examinations. Special attention was given to the branching pattern of the portal system and the relative positions of the umbilical portion of the portal vein, the ligamentum teres, and the gallbladder.

RESULTS

Four donor candidates (1.2%) had a portal vein anomaly associated with a rightward-deviated ligamentum teres. In all four, the umbilical portion of the portal vein (and hence the ligamentum teres) was abnormal, lying above the gallbladder bed and giving off major branches to the right anterior segment. If unrecognized, these might have been ligated, leading to major complications in the donors.

CONCLUSION

A portal vein anomaly associated with a rightward-deviated ligamentum teres is an important clinical entity that is not as rare as indicated in the literature. This anomaly should be kept in mind during preoperative examination of the liver.

Influence of chronic nitric oxide inhibition of coronary blood flow regulation: a study of the role of endogenous adenosine in anesthetized, open-chested dogs

The effect of chronic inhibition of endothelium-derived nitric oxide (NO) synthesis on the regulation of coronary blood flow (CBF) is yet to be elucidated. A chronic canine model of inhibited NO synthesis was created and the role of adenosine in the regulation of coronary blood flow in this model was examined. Dogs were fed a diet supplemented with 40 mg/kg per day N(G)-nitro-L-arginine methyl ester (L-NAME group, n=8) or a regular diet without L-NAME supplementation (control group, n=8) for 4 weeks. The experiments were performed in an anesthetized, open-chest state and the results were compared in the L-NAME and control groups. Chronic L-NAME treatment significantly increased arterial pressure. Neither basal CBF in the left anterior descending artery nor heart rate differed between the L-NAME and control groups. In the L-NAME group, the response of CBF to intracoronary acetylcholine and adenosine was blunted, but that to glyceryl trinitrate was not. In addition, myocardial reactive hyperemia following 20 sec coronary occlusion was blunted in the L-NAME group. During atrial pacing at a rate 60 beats/min faster than the sinus rate, CBF increased to a similar degree in the L-NAME and control groups, and systolic wall thickening (SWT) changed similarly in both groups. Intracoronary 8-phenyltheophylline (8-PT), an adenosine receptor blocker, decreased basal CBF in the L-NAME group but not in the control group. In the L-NAME group, pacing-induced increase in CBF was abolished and SWT deteriorated after 8-PT administration. Basal myocardial adenosine release was significantly increased in the L-NAME group compared with the control group. It is concluded that in anesthetized, open-chest dogs with chronic inhibition of NO synthesis, adenosine may play a compensatory role in the regulation of coronary blood flow, as concomitant blockade of adenosine causes deterioration of coronary circulation and cardiac function.

Effects of variation in exposure to airborne acetone and difference in work load on acetone concentrations in blood, urine, and exhaled air

Using a physiologically based pharmacokinetic (PBPK) model, the effects of variation of exposure concentration of acetone on three biological indicators--acetone concentrations in blood, urine, and exhaled air--were investigated. The effect of the difference in work load was also examined. It was confirmed that the model could be used to estimate acetone concentrations during fluctuating exposure by comparing simulated acetone concentrations with the corresponding values observed in field surveys. By inputting the exposure situations into the PBPK model, the variabilities of the biological indicators were simulated. The variation of acetone exposure was expressed by seven 1-hour time-weighted averages (CEXPs). The arithmetic means of the CEXPS were 200 and 750 ppm. The geometric standard deviations (GSDs) were 1.5, 2.0, and 3.0, representing low, moderate, and high variations, respectively. Work loads were set at 15 and 50 W. Consequently, there were 12 exposure situations. The acetone concentrations in venous blood (CB) and exhaled alveolar air (CA) at 1 minute after the end of the work shift were selected as biological indicators of exposure because they were predicted to decrease rapidly at the end of exposure and become relatively stable after 1 minute. The acetone concentration in urine excreted during the last 2 hours of the work shift (CU) was also used as a biological indicator. Simulation was repeated 100 times with randomly permuting CEXPs for each situation. The mean values of CB, CU, and CA showed almost no variation regardless of the difference in the GSD of CEXPs. The coefficients of variation increased with the GSD of CEXPs but were less than 0.2. Consequently, these variables were acceptable as biological indicators of daily average exposure for the same work load. However, the difference in work load greatly changed the mean values of CB, CU, and CA, thus making it difficult to use these variables as indicators of daily average exposure for different work loads.

Immune function and lifestyle of taxi drivers in Japan

Many studies have reported that stress affects the immune system. It is known that professional drivers are exposed to various forms of job-related stress. The aim of the present study was to investigate the job stress of taxi drivers based on the mitogen responses and cytokine production of peripheral blood lymphocytes (PBMC), combined with interviews on lifestyles and income. We examined randomly selected male taxi drivers aged 40-59 years who were members of the Kansai District Union of Private Railway, Hire, and Taxi at the end of 1992 and 1993. At the end of 1993, they were struck by a severe economic depression. The lymphocyte proliferative responses to phytohemagglutinin (PHA), concanavalin A (ConA), poke weed mitogen (PWM), and PHA-induced interleukin-2 (IL-2) and IL-4 production of the taxi drivers were at the same level as those of the control subjects as measured in 1992. The mitogen responses and IL-2 production of taxi drivers were found to have significantly decreased in 1993, while their IL-4 production was significantly elevated. Lifestyles of normal PHA respondents were significantly different from those of low-PHA respondents in 1992. However, in 1993, these differences were unclear. The immune alterations of taxi drivers who were prohibited from working overtime were more profound than those of the drivers who were allowed to do so. These results indicate that in addition to driving stress, the daily earnings affect taxi drivers as a strong stress or that induces immunological changes.

Studies on the antifungal activity of the new imidazole antimycotic lanoconazole in infected sites. Distribution in the skin and in vitro activity in the presence of stratum corneum

To answer the question why topically applied lanoconazole (CAS 101530-10-3, NND-318) is so highly effective in the treatment of dermatomycoses in both animal models and human patients, the antifungal activity of lanoconazole in infected sites was investigated. 1. Distribution of lanoconazole in rat skin: The distribution of lanoconazole within the dorsal skin of rats was examined by measurement of radioactivity and microscopic autoradiography. 24 h after dermal application of 14C-lanoconazole cream formulation, 83% of the total radioactivity in the skin was recovered from the stratum corneum, and thereafter the radioactivity decreased gradually up to 96 h. Metabolite analysis showed that more than 94% of the extractable radioactivity was lanoconazole itself after 24 and 48 h. Microautoradiograms of the skin also supported the radioactivity distribution. 2. In vitro antifungal activity in stratum corneum-containing medium: Candida albicans TIMM 2640 was incubated for 10 days at 27 degrees C in a vitamin-supplemented yeast carbon base medium containing 5 mg/ml of human stratum corneum and different concentrations of lanoconazole or bifonazole (CAS 60628-96-8, reference agent). Compared with the control culture, lanoconazole strongly inhibited fungal growth in a concentration dependent manner at concentration above 0.1 microgram/ml, resulting in a reduction of viable cell recovery to less than 50% after 10 days. The inhibitory activity of bifonazole was clearly weaker than that of lanoconazole. At concentrations of 0.1-10 micrograms/ml lanoconazole reduced keratinolytic acid proteinase activity in the culture-supernate to 40-70% of the control value, while bifonazole showed 50% reduction of the activity at a concentration of 10 micrograms/ml. These results indicate that lanoconazole is mainly distributed and retained in the stratum corneum after topical application where it exerts strong antifungal activity.

Extracellular fluid pathway inside the facial nerve fascicles

The extracellular fluid pathway in the facial nerve and the diffusion of a tracer from the facial nerve to other cranial nerves was examined in the rabbit. Sodium fluorescein solution was injected into either the facial nerve fascicles or the epineurial connective tissue as a tracer at the stylomastoid foramen and then localized by fluorescence microscopy. In the facial nerve, fluorescence was observed in the endoneurium and external nerve sheath (epineurium and perineurium) through the geniculate ganglion following injection into the nerve fascicles. The vestibular, trigeminal, and glossopharyngeal ganglia also showed fluorescence on the injection side in ganglion cells and intercellular connective tissues. The results suggested that the endoneurial connective tissue constitutes a diffusion pathway inside the facial nerve fascicles and that the extracellular fluid pathway from the facial nerve to these cranial ganglia may be related to the neural spread of inflammation or neoplastic metastasis.

Prednisolone therapy for intra-abdominal desmoid tumors in a patient with familial adenomatous polyposis

The management of intra-abdominal desmoid tumors in patients with familial adenomatous polyposis (FAP) is very difficult. Non-steroidal anti-inflammatory drugs (NSAIDs), anti-estrogenic agents, and steroids are most commonly used, because surgical removal of these tumors may result in severe morbidity, with local recurrence being common. We report a patient with FAP and intra-abdominal desmoid tumors that regressed markedly after prednisolone therapy. The patient, a 38-year-old woman, had undergone total colectomy and ileorectal anastomosis with a diagnosis of FAP with colon cancer. Approximately 17 months after the surgery, she noticed an elastic firm lump in the abdominal wall. She also experienced lower abdominal distension. Computed tomography (CT) of the lower abdomen showed an invasive heterogenous low-density mass occupying the intra-abdominal space. She was treated with sulindac, NSAID, at 300 mg/day, the diagnosis being intra-abdominal desmoid tumors. She exhibited an intestinal obstruction about 9 months after the initiation of sulindac therapy. We changed the treatment and began prednisolone (initial dose, 40 mg/day). This treatment was continued for two years; subsequently, the lesions regressed markedly. She is currently well, more than 3 years after the withdrawal of prednisolone.

The upper turnover site in the reentry circuit of common atrial flutter

The upper turnover site of the reentry circuit of common atrial flutter was examined with the uses of atrial activation mapping and extrastimulus techniques during atrial flutter. The findings suggest that it is anterior to the orifice of the superior vena cava, i.e., between the superior vena cava and tricuspid annulus.

Load on the low back of teachers in nursery schools

In order to evaluate the load on the low back of teachers in nursery schools, basic activity, working posture, child-lifting, and desk-lifting were analyzed for eight nursery teachers using video recording. The trunk inclination angle (TIA) was also measured continuously during full workshifts for 20 nursery teachers using an inclination monitor. The nursery teachers in the 0-1 (year) age class more often adopted low working postures, "sitting on the floor" and "kneeling," while teachers in the 4-5 age class more frequently adopted high working postures, "standing" and "sitting on a chair." The mean of TIA among all subjects was 20 degrees. The time spent at a TIA of more than 20 degrees represented 43% of the workshift. The mean and time distribution of TIA did not differ between the age classes. The frequency of trunk-lifting from severe bending forward (TIA > 45 degrees) was 86 times/hour on average. The frequency of trunk-lifting was highest in the 0-1 age class. The number of times of child-lifting was 46 in the 0-1 age class, while it was 1 in the 4-5 age class.

Impairment of coronary blood flow regulation by endothelium-derived nitric oxide in dogs with alloxan-induced diabetes

Diabetes mellitus is a major cause of ischemic coronary artery disease. Endothelial dysfunction is implicated in the pathogenesis of diabetic vascular disease. To examine coronary blood flow (CBF) regulation with endothelium-derived nitric oxide (EDNO) in the diabetic state, we compared the effects of both acetylcholine (ACh) and adenosine (Ado) on left circumflex coronary artery (LCX) blood flow in 12 vehicle-treated and 21 dogs made diabetic with alloxan anesthetized with pentobarbital. All dogs were pretreated with aspirin to inhibit endogenous prostaglandins. None of the hemodynamic parameters were significantly different in the two groups. The percent change in coronary vascular resistance (CVR) after ACh (100 ng/kg) infusion was significantly attenuated in diabetic dogs (-56.5 +/- 1.4%) as compared with vehicle-treated dogs (-64.5 +/- 1.2%) (p < 0.01), whereas the effect of Ado (1 microgram/kg) was not different between the two groups (-71.1 +/- 1.5% in vehicle, -67.0 +/- 1.3% in diabetes). After infusion of incremental doses of NG-nitro-L-arginine methyl ester (L-NAME) 10(-5)-10(-3)M, the effect of ACh was progressively inhibited in both groups and was different no longer between the two groups after the maximal dose. L-Arginine (L-ARG), but not D-ARG, significantly restored the effect of ACh in diabetic dogs but did not affect vehicle-treated dogs. The effect of Ado did not change after L- and D-ARG administration. Cu, Zn-superoxide dismutase (Cu, Zn-SOD) had no effect on any of the effects of ACh and Ado in diabetic dogs. Regulation of CBF with EDNO is impaired in dogs with alloxan-induced diabetes, and this impairment is partially restored by L-ARG.

Correlation between lead in plasma and other indicators of lead exposure among lead-exposed workers

In order to clarify the bioavailability of lead in plasma (PbP), we performed a study on five workers in a Japanese factory manufacturing lead glass-based paints. Blood and urine samples were obtained over a period of 15 months, during which time the workers took it in turns to perform sifting work (with the highest level of lead exposure) for 1-month periods. A total of 75 sets of blood and urine samples were thus obtained. We determined whole blood lead (PbB), PbP, Urinary coproporphyrin (CPU), urinary delta-aminolevulinic acid (ALAU), urinary lead (PbU) and ALA in plasma (ALAP). In the 15 sets of samples obtained at the end of the period with a high level of lead exposure, PbP correlated significantly with ALAU, CPU, PbU and ALAP, but PbB correlated significantly only with PbU. In the 60 sets of samples obtained following a low level of lead exposure, correlation coefficients between the concentrations of PbP and of ALAU, CPU and PbU exceeded those between the concentrations of PbB and of ALAU, CPU and PbU. These findings indicate that PbP is a better dose indicator of lead biochemically available for heme synthesis and that PbU has a closer correlation with PbP than with PbB.

Effects of angiotensin-converting enzyme inhibitor alacepril in patients with stable effort angina during chronic isosorbide dinitrate treatment

Nitrate tolerance has been reported to be reversed by certain types of angiotensin-converting enzyme (ACE) inhibitors. We examined whether alacepril, a new long-acting oral ACE inhibitor, has beneficial effects against exercise-induced angina in patients with stable effort angina after substantial isosorbide dinitrate (ISDN) treatment. Thirteen men with stable effort angina were treated with oral ISDN (80 mg/d) for >3 weeks. After this period, efficacy of single oral administration of either alacepril (50 mg) or its placebo on exercise-induced angina and electrocardiographic changes was examined by treadmill exercise test in a double-blind crossover design. Alacepril significantly improved the exercise duration by 9.1% (p=0.03), the time to 1 mm ST-segment depression by 19% (p<0.01), and the maximal ST-segment depression by 33% (p=0.015) compared with placebo. Alacepril did not significantly alter the rate-pressure product, a marker of myocardial oxygen demand, during exercise test compared with placebo. Plasma renin activity was significantly increased (p<0.05) after administration of alacepril, indicating that alacepril significantly blocked ACE activity in our patients. In conclusion, a single oral administration of the ACE inhibitor alacepril (50mg) elicited beneficial effects against exercise-induced myocardial ischemia in patients with stable effort angina during chronic nitrate treatment. These effects may be mediated by increased coronary blood flow.

Double atrial responses to a single ventricular impulse in long RP' tachycardia

Double atrial responses (DARs) to a single ventricular impulse have been described in patients with long RP' tachycardia. To define the determinants for the occurrence of DARs, 8 cases with long RP' tachycardia were examined. The mechanism of long RP' tachycardia was the orthodromic atrioventricular reciprocating tachycardia (AVRT) involving a slow conducting concealed accessory pathway in 4 cases and uncommon (fast-slow) type of atrioventricular nodal reentrant tachycardia (AVNRT) in the other 4 cases. Programmed and rapid ventricular pacing was performed during sinus rhythm and also rapid ventricular pacing during tachycardia (i.e., entrainment). The retrograde effective refractory period (ERP) and the retrograde maximal 1:1 conduction rate of the fast and slow conducting pathways were examined. In 1 of the 4 cases with AVRT, DARs were observed during programmed and rapid ventricular pacing, performed during sinus rhythm and also during entrainment. In 1 of the 4 cases with AVNRT, DARs were observed only during entrainment. The determinants of DARs in cases with long RP' tachycardia were: (1) presence of two different retrogradely conducting pathways; (2) short ERP of the retrograde fast and slow conducting pathways and a short minimal pacing cycle length at which 1:1 ventriculoatrial conduction occurs via these pathways; (3) crucial conduction delay in the slow conducting pathway; and (4) preexisting antegrade unidirectional block in the slow conducting pathway or the antegrade block in the slow conducting pathway produced by collision with a previous retrograde impulse during entrainment.