Gaseous nitrous acid (HONO) and nitrogen oxides (NOx) emission from gasoline and diesel vehicles under real-world driving test cycles

Reactive nitrogen species emission from the exhausts of gasoline and diesel vehicles, including nitrogen oxides (NO_x) and nitrous acid (HONO), contributes as a significant source of photochemical oxidant precursors in the ambient air. Multiple laboratory and on-road exhaust measurements have been performed to estimate the NO_x emission factors from various vehicles and their contribution to atmospheric pollution. Meanwhile, HONO emission from vehicle exhaust has been under-measured despite the fact that HONO can contribute up to 60% of the total hydroxyl budget during daytime and its formation pathway is not fully understood. A profound traffic-induced HONO to NO_x ratio of 0.8%, established by Kurtenbach et al. since 2001, has been widely applied in various simulation studies and possibly linked to under-estimation of HONO mixing ratios and OH radical budget in the morning. The HONO/NO_x ratios from direct traffic emission have become debatable when it lacks measurements for direct HONO emission from vehicles upon the fast-changing emission reduction technology. Several recent studies have reported updated values for this ratio. This study has reported the measurement of HONO and NO_x emission as well as the estimation of exhaust-induced HONO/NO_x ratios from gasoline and diesel vehicles using different chassis dynamometer tests under various real-world driving cycles. For the tested gasoline vehicle, which was equipped with three-way catalyst after-treatment device, HONO/NO_x ratios ranged from 0 to 0.95 % with very low average HONO concentrations. For the tested diesel vehicle equipped with diesel particulate active reduction device, HONO/NO_x ratios varied from 0.16 to 1.00 %. The HONO/NO_x ratios in diesel exhaust were inversely proportional to the average speeds of the tested vehicles.

IMPLICATIONS

Photolysis of HONO is a dominant source of morning OH radicals. Conventional traffic-induced HONO/NO_x ratio of 0.8% has possibly linked to underestimation of the total HONO budget and consequently underestimation of OH radical budget. The recently reported HONO/NO_x ratio of ~1.6% was used to stimulate HONO emission, which resulted in increased HONO concentrations during morning peak hours and its impact of 14% OH increment in the morning. However, the results were still lower than the measured concentrations. More studies should be conducted to establish an updated traffic-induced HONO/NO_x ratio.

Post-transplant renal function and cardiovascular events are closely associated with the aortic calcification index in renal transplant recipients

INTRODUCTION

The aortic calcification index (ACI) is reported to be closely associated with renal dysfunction and cardiovascular events; however, its implication in renal transplant recipients has not been well examined. In this study, we investigated the relationship between pretransplant ACI, ACI progression, post-transplant renal function, and post-transplant cardiovascular events in renal transplant recipients.

PATIENTS AND METHODS

The study from June 1996 to Jan 2012 included 61 renal transplant recipients (living donors, 47; cadaveric donors, 14). The median follow-up period was 60 months. ACI was quantitatively measured on abdominal computed tomography. The relationship between age, dialysis period, estimated glomerular filtration rate (eGFR), and pre- and post-transplant ACI was longitudinally evaluated. Risk factors for post-transplant ACI progression were determined by logistic regression analysis. Patient background and the incidence of post-transplant cardiovascular events were also assessed.

RESULTS

The pretransplant ACI (median 4.2%) significantly correlated with age at transplant, dialysis period, and diabetes mellitus. ACI gradually increased up to 2.8 times at 10 years after transplantation. Post-transplant eGFR significantly correlated with ACI progression in patients with chronic kidney disease of stage ≥ 3. Logistic regression analyses showed that age at transplantation, post-transplant period, cadaveric donors, and post-transplant chronic kidney disease stage 3 were risk factors for post-transplant ACI progression. The pretransplant ACI was higher (median 66%) in 3 patients who experienced post-transplant cardiovascular events.

CONCLUSIONS

ACI progression closely correlates with age and post-transplant renal function. A high pretransplant ACI is a risk factor for post-transplant cardiovascular events in renal transplant recipients.

A primary retroperitoneal serous cystadenocarcinoma with clinically aggressive behavior

CASE REPORT

We describe a 44-year-old woman with a primary retroperitoneal serous cystadenocarcinoma as the fourth report in the world literature. A contrast-enhanced computed tomographic scan of the abdomen demonstrated a mass with enhanced solid mural nodules and septa in the left retroperitoneum. Serum CA19-9 was elevated at 181 U/ml. The patient underwent a complete resection of the retroperitoneal tumor with a partial resection of the psoas major muscle and its fascia. Pathological examination showed a well-differentiated papillary serous cystadenocarcinoma of ovarian type and locoregional lymph node metastases. Seven months after surgery, the patient developed a pelvic recurrence, and underwent a total hysterectomy, a left salpingo-oophorectomy and a resection of the metastatic mesenteric mass. Two months after the second surgery, serum CA19-9 and CA125 increased to 1,114 U/ml and 218 U/ml, respectively. A solitary liver metastasis was confirmed on a computed tomographic scan. The patient is now being treated with weekly docetaxel and carboplatin.

CONCLUSION

The present case illustrates the clinically aggressive nature of a primary retroperitoneal serous cystadenocarcinoma.

Coffee consumption and serum aminotransferases in middle-aged Japanese men

We investigated the relation between coffee drinking and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations among 7313 Japanese men receiving a health examination, excluding former alcohol drinkers and men with a history of chronic liver disease. Serum AST > 40 and/or ALT > 40 U/L was defined as liver inflammation. Adjustment was made for alcohol use, smoking, body mass index, serum marker for hepatitis virus infection, and other possible confounders. Adjusted odds ratios of liver inflammation were 1.00 (reference), 0.80, 0.69, and 0.61 for men drinking < 1, 1-2, 3-4, and > or = 5 cups of coffee daily, respectively. Among 6898 men without liver inflammation, serum AST and ALT were inversely associated with coffee consumption, and alcohol-related rise in AST was attenuated with coffee drinking. These findings suggest coffee may have an effect of suppressing the rise of serum aminotransferase, partly by inhibiting the alcohol-related elevation. Studies regarding biological mechanism are warranted.

Functional uncoupling of T-cell receptor engagement and Lck activation in anergic human thymic CD4+ T cells

Human thymic CD1a-CD4+ T cells in the final stage of thymic maturation are susceptible to anergy induced by a superantigen, toxic shock syndrome toxin-1 (TSST-1). Thymic CD4+ T-cell blasts, established by stimulating human thymic CD1a-CD4+ T cells with TSST-1 in vitro, produce a low level of interleukin-2 after restimulation with TSST-1, whereas TSST-1-induced adult peripheral blood (APB) CD4+ T-cell blasts produce high levels of interleukin-2. The extent of tyrosine phosphorylation of the T-cell receptor zeta chain induced after restimulation with TSST-1 was 2-4-fold higher in APB CD4+ T-cell blasts than in thymic CD4+ T-cell blasts. The tyrosine kinase activity of Lck was low in both thymic and APB CD4+ T-cell blasts before restimulation with TSST-1. After restimulation, the Lck kinase activity increased in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Surprisingly, Lck was highly tyrosine-phosphorylated in both thymic and APB CD4+ T-cell blasts before restimulation with TSST-1. After restimulation, it was markedly dephosphorylated in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Lck from APB CD4+ T-cell blasts bound the peptide containing the phosphotyrosine at the negative regulatory site of Lck-505 indicating that the site of dephosphorylation in TSST-1-activated T-cell blasts is Tyr-505. Confocal microscopy demonstrated that colocalization of Lck and CD45 was induced after restimulation with TSST-1 in APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. Further, remarkable accumulation of Lck in the membrane raft was observed in restimulated APB CD4+ T-cell blasts but not in thymic CD4+ T-cell blasts. These data indicate that interaction between Lck and CD45 is suppressed physically in thymic CD4+ T-cell blasts and plays a critical role in sustaining an anergic state.

Is communication to endocardium necessary for angiogenesis in transmyocardial laser revascularization?

There is evidence of angiogenesis being induced after transmyocardial laser revascularization (TMLR), although the precise mechanism has not been fully elucidated. This study was designed to examine whether or not blood flow from the left ventricle through the channels is essential for angiogenesis following TMLR. Ten dogs underwent the creation of two types of laser channels in the left ventricle: 1) a transmural channel (TMC), which penetrates the myocardium, and 2) a non-transmural channel (NTMC), which does not open to the epicardium. The animals were sacrificed on the 28th postoperative day and the vascular density was examined. Vessels with smooth muscle media were seen within or around the channel remnant. The vessel density was compared between TMC and NTMC. The outer and inner halves of the myocardium in the TMC region were compared in the same way. The density of vessels within and around the channel remnants was significantly higher in TMC than in NTMC (1.439 versus 0.685 vessels/microscopic visual field (mvf=40X); p=0.0025). The vascular density was significantly higher in the region adjacent to TMC than in a distant region (>3 mm from the channel center). The vascular density was significantly higher in the outer half than in the inner half of the myocardium (1.730 versus 1.180 vessels/mvf: p=0.0459). These findings demonstrate that communication to the left ventricular lumen enhances angiogenesis of TMLR, although blood flow in the channel did not exist 4 weeks after TMLR and angiogenesis tended to be more highly enhanced in the outer half than in the inner half of the myocardium.

Immunopathophysiological aspects of an emerging neonatal infectious disease induced by a bacterial superantigen

We recently discovered an emerging neonatal infectious disease, neonatal toxic shock syndrome-like (TSS-like) exanthematous disease (NTED), which is induced by a superantigen, TSS toxin-1 (TSST-1), produced by methicillin-resistant Staphylococcus aureus (MRSA). Here, we analyzed the activation and the response of TSST-1-reactive Vss2(+) T cells in NTED patients during the acute and recovery phases and in asymptomatic infants exposed to MRSA. In the acute phase, Vss2(+) T cells were anergic to stimulation with TSST-1 and underwent marked expansion, but by 2 months after disease onset, their numbers had declined to about 10% of the control level. Although the percentage of Vss2(+) T cells in the ten asymptomatic neonatal MRSA carriers was within the control range, these individuals could be divided into two groups on the basis of Vss2(+) T-cell activation. Vss2(+)CD4(+) T cells from three of these infants (Group 1) highly expressed CD45RO and were anergic to TSST-1, whereas in the other seven asymptomatic neonatal MRSA carriers (Group 2), these cells expressed CD45RO at the control level and were highly responsive to stimulation with TSST-1. The serum anti-TSST-1 IgG Ab titer was negligible in the four NTED patients in the acute phase and the three asymptomatic neonatal MRSA carriers in Group 1, but it was high in the seven asymptomatic carriers in Group 2. We suggest that maternally derived anti-TSST-1 IgGs helps to suppress T-cell activation by TSST-1 and protects infants from developing NTED.

Activation of the beta-catenin gene by interstitial deletions involving exon 3 as an early event in colorectal tumorigenesis

beta-Catenin has been identified as an oncogene in several tumors including colorectal cancers. beta-Catenin gene is activated by interstitial deletions involving exon 3 in colorectal carcinomas of Japanese population, in contrast to amino acid substitutions detected among Caucasian population. The aim of this study was to examine the type and frequency of beta-catenin gene mutation during early stages of colorectal tumorigenesis. We screened 100 colorectal adenomas for somatic mutations in the beta-catenin gene by single-strand conformation polymorphism method, as well as polymerase chain reaction amplification. In cases with mutations, sequencing analyses and immunohistochemical staining were also performed. Somatic interstitial deletions of 272-413 bp, each of which included all parts of exon 3, were detected in three tumors. However, no adenoma carried missense mutations. We confirmed accumulation of aberrant beta-catenin protein in cytoplasm and nuclei of adenoma cells by immunohistochemical analysis. Our results suggested that activation of the beta-catenin gene by interstitial deletions involving exon 3 might be less frequent compared with frequent alterations of adenomatous polyposis coli (APC) gene, but could be an early event in colorectal tumorigenesis equivalent to APC gene alterations in the Japanese population.

Relationship between serologically diagnosed chronic atrophic gastritis, Helicobacter pylori, and environmental factors in Japanese men

BACKGROUND

Whereas chronic atrophic gastritis is known to be an intermediate stage in gastric carcinogenesis, information is sparse about factors associated with this precancerous lesion except for Helicobacter pylori.

METHODS

In a cross-sectional study of 566 men aged 50-55 years in the Japan Self-Defense Forces, we examined the relation of H. pylori infection, smoking, alcohol use, and dietary factors to the prevalence of chronic atrophic gastritis as determined by serum pepsinogen I and pepsinogen II (I/II ratio < 3.0. and pepsinogen I < 70 ng/ml). Chronic atrophic gastritis was classified as severe when the pepsinogen I/II ratio was < 2.0, and as moderate otherwise.

RESULTS

The overall prevalence of chronic atrophic gastritis was 35.7% (202 of 566). The seropositivity of H. pylori was associated with a 10-fold increase in the risk of chronic atrophic gastritis, and the association was much stronger for moderate atrophic gastritis. Neither cigarette smoking nor alcohol consumption was related to the overall risk of chronic atrophic gastritis. Consumption of vegetables and fruits was each unrelated to chronic atrophic gastritis whether examined as a whole or separately for moderate and severe atrophic gastritis. Green tea was related to decreased risk of severe atrophic gastritis, although not statistically significant, whereas garlic consumption showed no protective association.

CONCLUSIONS

The findings corroborate that H. pylori infection has an important role in the development of chronic atrophic gastritis in middle-aged Japanese men. Green tea consumption may be protective against the advance of atrophic gastritis. Vegetables, fruits, or garlic had no protective effect against the development of atrophic gastritis in the study.

Coffee drinking and serum gamma-glutamyltransferase: an extended study of Self-Defense Officials of Japan

PURPOSE

To examine the effect of coffee drinking on serum gamma-glutamyltransferase (GGT) level in relation to alcohol drinking, smoking, and degree of obesity in middle-aged Japanese men.

METHODS

From 1986 to 1994, a total of 7,637 male officials of the Self-Defense Forces of Japan aged 48-59 years received a preretirement health examination. Coffee drinking was ascertained by a self-administered questionnaire, and serum GGT level was measured. After excluding 1,360 men with a possible pathologic condition influencing liver enzyme levels and 182 former alcohol drinkers, effect of coffee drinking on serum GGT was examined by a multiple linear regression model and analysis of variance adjusting for alcohol drinking, smoking, and body mass index (BMI).

RESULTS

The adjusted percentage of difference in serum GGT was -4.3 (95% CI = -5.0; -3.5) per cup of coffee. The inverse coffee-GGT relation was most prominent among men drinking > or = 30 ml of ethanol and smoking > or = 15 cigarettes daily; and positive associations of alcohol and smoking with GGT were attenuated by coffee drinking, more clearly among men with BMI > or = 25.00 kg/m2. Adjusted percentages of difference in serum GGT were -2.6% (p = 0.0003) per cup of brewed coffee, and -5.1% (p = 0.0001) per cup of instant coffee, independently of each other.

CONCLUSIONS

The present study suggests that coffee consumption may weaken GGT-induction by alcohol, and possibly by smoking. These effect modifications by coffee may differ according to the degree of obesity.

[Kidney]

Kidney is one of the major target organ for angiotensin II (AT-II). The presence of three types of AT-II receptors, AT-II type 1, type 2, type 4 receptor (AT1, AT2, and AT4 receptor, respectively) were reported in kidney. AT1 receptor is the main type of receptor in kidney and mediates most of physiological effects of AT-II in kidney. The population of AT2 receptor is small in kidney. However, AT2 receptor also seems to play an important role for development and apoptosis in kidney. AT4 receptor is the receptor for angiotensin IV, but the physiological function is still unknown.

Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan

The study aims to examine the relationship between habitual coffee consumption and blood pressure. The subjects were 3336 male self-defense officials aged 48-56 years, who received a preretirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1992. Average coffee intake in the past year was ascertained by a self-administered questionnaire. A significant inverse relation between habitual coffee consumption and blood pressure was found with and without adjustment for alcohol use, cigarette smoking, body mass index, glucose tolerance, and green tea intake. Green tea, another major source of caffeine intake in Japanese, was unrelated to blood pressure. The adjusted mean differences per cup of coffee consumed per day were -0.6 mmHg (95% confident interval [CI]: -0.9 to -0.3, p = 0.0001) in systolic blood pressure and -0.4 mmHg (95% CI: -0.5 to -0.2, p = 0.0002) in diastolic blood pressure. Habitual coffee drinkers had lower blood pressure than non-drinkers at any levels of alcohol use, cigarette smoking, obesity, and glucose intolerance. Our findings consolidate the previous observation that habitual coffee consumption was associated with lower blood pressure.

Relationship of cigarette smoking, alcohol use, recreational exercise and obesity with serum lipid atherogenicity: a study of self-defense officials in Japan

We investigated the relationship of cigarette smoking, alcohol use, recreational exercise and obesity with serum lipid atherogenicity because of paucity of epidemiological studies. The subjects were 2,228 male officials of the Self-Defense Forces in Japan, who were aged 49-55 years and received a preretirement health examination in the period from 1991 to 1992. A self-administered questionnaire was used to ascertain cigarette smoking, alcohol use and recreational exercise. Serum total cholesterol (TC) and low-density-lipoprotein cholesterol (LDL-C) were increased with increasing levels of body mass index (BMI) and waist-to-hip ratio (WHR), and decreased with increasing levels of cigarette smoking and alcohol use. Serum high-density-lipoprotein cholesterol (HDL-C) was positively associated with alcohol use and recreational exercise, and negatively associated with cigarette smoking, BMI and WHR. BMI and alcohol use were most strongly associated with both LDL-C/HDL-C and TC/HDL-C ratios with BMI in an atherogenic direction and alcohol use in an antiatherogenic direction. Recreational exercise was weakly associated with less atherogenic lipid profile. BMI was the strongest determinant of serum lipid atherogenicity whereas alcohol use was most antiatherogenic. WHR was less important than BMI in the determination of serum lipid atherogenicity in Japanese men.

Exanthematous disease induced by toxic shock syndrome toxin 1 in the early neonatal period

BACKGROUND

We have seen a number of patients who developed systemic exanthema and thrombocytopenia in the first week of life. Although nearly 100% of the patients were carriers of meticillin-resistant Staphylococcus aureus (MRSA), no clear link between MRSA and this exanthematous disease has yet been made.

METHODS

20 neonates with exanthema and thrombocytopenia were selected for study. To see whether superantigenic exotoxins from MRSA are involved in the pathogensis of the exanthematous disease, we studied the production of these exotoxins by MRSA isolates from the neonates. We studied the expression of T-cell-receptor Vbeta and CD45RO in T cells taken from four of the neonates. We also analysed the DNA sequences of 16 cloned Vbeta2-positive T-cell-receptor-chain genes taken from two of the neonates.

FINDINGS

Although most of the patients recovered within 5 days of onset of the exanthematous disease without any active treatment, two preterm infants died in the recovery phase. All patients showed colonisation by MRSA. The MRSA produced toxic shock syndrome toxin-1 (TSST-1). The number of T cells positive for T-cell-receptor Vbeta2, reactive to TSST-1, was increased in the four patients studied (p<0.0001), and these T cells expressed CD45RO (p=0.0185). None of the Vbeta2 clones had the same junctional sequences.

INTERPRETATION

The polyclonal expansion of Vbeta2-positive T cells in patients colonised by TSST-1-producing MRSA suggests that the pathogenic micro-organism of this neonatal exanthematous disease is S aureus, mainly MRSA, and that in its pathogenesis it activates T cells by TSST-1. Although the pathogenesis of both this exanthematous disease and toxic shock syndrome are fundamentally the same, a diagnosis of toxic shock syndrome cannot be made in this case, based on the clinical criteria for toxic shock syndrome. We propose neonatal toxic-shock-syndrome-like exanthematous disease (NTED) as the name for this disease.

cDNA cloning, expression, and mutagenesis of scytalone dehydratase needed for pathogenicity of the rice blast fungus, Pyricularia oryzae

We purified scytalone dehydratase from the rice blast fungus, Pyricularia oryzae, and cloned its cDNA on the basis of its amino acid sequence. The deduced amino acid sequence was 62% identical to the scytalone dehydratase from Colletotrichum lagenarium. The expression of this gene was induced transcriptionally in the stationary phase when melanin synthesis occurs. We constructed a heterologous expression system for the enzyme in Escherichia coli, did deletion analysis with this system, and found that a C-terminal region is essential for the enzyme function.

Physiological control of a total artificial heart: conductance- and arterial pressure-based control

To obtain a physiological response by a total artificial heart (TAH), while eliminating the hemodynamic abnormalities commonly observed with its use, we proposed the use of a conductance- and arterial pressure-based method (1/R control) to determine TAH cardiac output. In this study, we endeavored to make use of a variable more closely tied to central nervous system (CNS) efferents, systemic conductance, to provide the CNS with more direct control over the output of the TAH. The control equation that calculates the target cardiac output of the TAH was constructed on the basis of measurement of blood pressures and TAH flow. The 1/R control method was tested in TAH-recipient goats with an automatic method by using a microcomputer. In 1/R control animals, the typical TAH pathologies, such as mild arterial hypertension and substantial systemic venous hypertension, did not occur. Cardiac output varied according to daily activity level and exercise in a manner similar to that observed in natural heart goats. These results indicate that we have determined a control method for the TAH that avoids hemodynamic abnormalities exhibited by other TAH control systems and that exhibits physiological responses to exercise and daily activities under the conditions tested. The stability of the control and the complete lack of inappropriate excursions in cardiac output is suggestive of CNS involvement in stabilizing the system.

Post-thymic maturation of migrating human thymic single-positive T cells: thymic CD1a- CD4+ T cells are more susceptible to anergy induction by toxic shock syndrome toxin-1 than cord blood CD4+ T cells

To determine whether human CD4+ T cells undergo post-thymic maturation, we compared the susceptibility to anergy induction in human thymic CD1a- CD4+ single-positive (CD4+), cord blood (CB) CD4+, and adult peripheral blood (APB) CD4+ T cells by stimulation with toxic shock syndrome toxin-1 (TSST-1). Most TSST-1-induced T cell blasts derived from either T cell preparation expressed TCR Vbeta2, which determines the potential reactivity to TSST-1. Most thymic CD4+ T cell blast preparations exhibited little or no production of IL-2 and IL-4 after restimulation with TSST-1 and only marginal responses after stimulation with rIL-2 or a combination of PMA and calcium ionophore, while the APB CD4+ T cell blasts showed high responses to these stimuli. The responses of CB CD4+ T cell blasts to these stimuli varied, ranging from minimal to relatively high. Studies of DNA fragmentation showed that there was no significant cell death of thymic CD4+ T cell blasts. Most thymic CD1a- CD4+ and CB CD4+ T cells were CD38 positive. APB CD4+ T cell blasts derived from the CD38+ fraction and from the CD38- fraction exhibited equally high responses to restimulation with TSST-1. These results indicate that thymic CD1a- CD4+ and CB CD4+ T cells are inherently highly susceptible to anergy induction by bacterial superantigens and that thymic CD1a- CD4+ T cells are less mature than CB CD4+ T cells, suggesting that post-thymic maturation in thymic T cells migrating to the periphery is required for acquisition of full reactivity to antigenic stimulation.

Anticipation of job loss or job change and cardiovascular risk factors: a study of retiring self-defense officials in Japan

Self-defense officials in Japan are to retire at the age of early 50s. This unique situation prompted the authors to investigate whether preexisting morbid conditions cause any difficulty in finding a post-retirement job and whether anticipation of job loss or job change, as measured by the status of post-retirement job and months remaining until retirement, was related to biological cardiovascular risk factors. The subjects were 2,228 male self-defense officials who received a preretirement health examination at three Self-Defense Forces Hospitals from 1991 to 1992; the period in time remaining until retirement ranged from 1-40 months (median 12 months), and 62% had one year or less until the retirement. The defined preexisting illnesses included a wide range of chronic, non-communicable diseases. Overall, the preexisting illness was unrelated to the determination of a post-retirement job. In men having 6 months or less until retirement, however, the security of post-retirement job was less frequent when they had the preexisting illness, especially cardiovascular diseases. In 1,839 men excluding those with the preexisting illness, the period until retirement was not adversely related to obesity, blood pressure, serum lipids, serum uric acid, or glucose intolerance whether the post-retirement job had been secured or not. The findings suggest that the preexisting illness decreases the chance of obtaining a post-retirement job, but do not provide any evidence that anticipation of job loss or job change due to early retirement exerts an adverse effect on biological cardiovascular risk factors.

Vasoactive intestinal polypeptide and pituitary adenylate cyclase-activating polypeptide receptor chimeras reveal domains that determine specificity of vasoactive intestinal polypeptide binding and activation

Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) receptors are closely related G protein-coupled receptors with seven-transmembrane domains. The VIP receptor can bind both VIP and PACAP with high affinity, whereas the PACAP receptor binds only PACAP with high affinity. To elucidate the structural domains involved in a selectivity for VIP binding and the subsequent receptor activation, a series of chimeric receptors between the VIP and PACAP receptors was constructed, expressed in COS-7 cells, and analyzed for ligand binding and cAMP generation. All chimeric constructs bound PACAP with high affinity and subsequently activated cAMP generation similarly to the wild-type receptors. In contrast, profound differences were observed in the potencies of VIP for competition of 125I-labeled PACAP binding to both wild-type receptors and the chimeric receptors. The cAMP responses of these receptors generally correlated with the ability of VIP to compete for PACAP radioligand binding with the exceptions for some particular chimeras. In this report we demonstrate that several domains, including the amino-terminal extracellular domain, the transmembrane domains I and II, and the first extracellular loop of the VIP receptor, are important for the selectivity for VIP binding and responsiveness to VIP. We further show that the third extracellular loop and its proximal domains of the VIP receptor appear to be involved in the VIP recognition, especially the receptor activation process. On the other hand, the direct binding experiments of the VIP radioligand demonstrated that both wild-type receptors and all chimeric receptors have a high affinity binding site for VIP, although this high affinity VIP binding resulted in a biological response only in the VIP receptor or VIP receptor-like chimeras. This suggests that there is a nonbiologically relevant high affinity VIP-binding site within the rat PACAP receptor.

Relationship of cigarette smoking, alcohol use, and dietary habits with Helicobacter pylori infection in Japanese men

BACKGROUND

Little is known of factors determining infection with Helicobacter pylori.

METHODS

In a cross-sectional study of 566 men aged 50-55 years, who received a preretirement health examination at the Self Defense Forces Fukuoka Hospital between January 1993 and December 1994, we examined the association of smoking, alcohol use, and dietary habits with H. pylori infection.

RESULTS

The overall seropositivity as determined with IgG antibody was 79.3% (449 of 566). The rank was inversely associated with the infection (trend, P = 0.048). Neither smoking nor alcohol drinking was related to the infection. The prevalence adjusted for rank tended to be lower in men consuming raw vegetables (trend, P = 0.12) daily than those with less consumption. Unexpectedly, the consumption of tofu (soybean curd) was significantly, negatively related to the infection (trend, P = 0.013). The seropositivity was unrelated to the consumption of pickled vegetables, soy paste soup, green tea, or garlic.

CONCLUSION

The findings suggest that fresh vegetables may be protective against H. pylori infection. The study does not support either an increased risk of the infection associated with salty foods or a protective effect of green tea or garlic.

Behavioral correlates of plasma sex hormones and their relationships with plasma lipids and lipoproteins in Japanese men

In contrast to the hypothesis that endogenous testosterone decreases plasma high-density lipoprotein (HDL) cholesterol levels, many, but not all, studies have reported a positive correlation between plasma total testosterone and HDL cholesterol. We examined behavioral correlates of plasma testosterone and estradiol and the relationships between these sex hormones and plasma lipoproteins, in middle-aged Japanese men. Plasma, lipids, including HDL subfractions, total and free testosterone, and total estradiol were determined with 313 men aged 50-54 years who received a preretirement health examination at the Self-Defence Forces Fukuoka Hospital from January to June in 1992. Body mass index and waist-hip ratio were also measured. Smoking habit, alcohol use, and physical activity were ascertained by a self-administered questionnaire. Obesity, especially waist-hip ratio, was a strong correlate of both total and free testosterone, but not of estradiol. Smoking was associated with elevated levels of testosterone without a dose-effect relation. Neither alcohol use nor physical activity was associated with total or free testosterone, but plasma estradiol levels were higher among current alcohol drinkers. HDL and HDL2 cholesterol were unrelated to either total or free testosterone in the univariate analysis, but negatively associated with free, not total, testosterone after adjustment for obesity. HDL and HDL2 cholesterol also were positively associated with estradiol regardless of adjustment for obesity and other covariates. These findings add to evidence for a hypothesis that high levels of endogenous testosterone and low estradiol levels may cause a decrease in plasma HDL cholesterol, thereby being linked with atherosclerosis in middle aged men.

Use of a Catecholamine Sensor in the Control of an Artificial Heart System

An electrochemical sensor system to allow real-time measurement and feedback of catecholamine concentrations was developed for use in the control of artificial hearts. Electrochemical analyses were carried out using a carbon fiber working electrode, an Ag-AgCI reference electrode, and a potentiostat. The operating parameters of the pneumatically-driven artificial heart system were altered in accordance with the algorithm for changes in the catecholamine concentration. The minimum detectable concentrations of both adrenaline and noradrenaline in a mock circulatory system using a phosphate-buffered solution were approximately 1-2 ng/ml (10-8 mol/L). An artificial heart control system utilizing this set-up performed satisfactorily without delay, although sensor sensitivity decreased when placed in goat plasma instead of a phosphate-buffered solution, due to the adsorption of various substances such as plasma proteins onto the electrodes. This study demonstrated the future feasibility of a feedback control system for artificial hearts using catecholamine concentrations.

Use of a catecholamine sensor in the control of an artificial heart system

An electrochemical sensor system to allow real-time measurement and feedback of catecholamine concentrations was developed for use in the control of artificial hearts. Electrochemical analyses were carried out using a carbon fiber working electrode, an Ag-AgCl reference electrode, and a potentiostat. The operating parameters of the pneumatically-driven artificial heart system were altered in accordance with the algorithm for changes in the catecholamine concentration. The minimum detectable concentrations of both adrenaline and noradrenaline in a mock circulatory system using a phosphate-buffered solution were approximately 1-2 ng/ml (10(-8) mol/L). An artificial heart control system utilizing this set-up performed satisfactorily without delay, although sensor sensitivity decreased when placed in goat plasma instead of a phosphate-buffered solution, due to the adsorption of various substances such as plasma proteins onto the electrodes. This study demonstrated the future feasibility of a feedback control system for artificial hearts using catecholamine concentrations.

Synovial mononuclear cells consist with T cells which produce high levels of tumor necrosis factor alpha

To determine whether synovial mononuclear cells include a population of tumor necrosis factor alpha-producing T cells, we measured tumor necrosis alpha levels in culture supernatants of synovial mononuclear cells by ELISA and analyzed tumor necrosis alpha mRNA-positive cell frequencies. There were no significant differences in the spontaneous levels of TNF alpha between synovial mononuclear cells and peripheral mononuclear cells. The frequency of tumor necrosis factor alpha mRNA-positive cells in synovial mononuclear cells was higher than that of peripheral mononuclear cells. When stimulated with a superantigen, mononuclear cells from the synovial fluid of rheumatoid arthritis patients showed higher levels of tumor necrosis factor alpha production (1,035 +/- 817 pg/ml) than did mononuclear cells from their peripheral blood (236 +/- 180 pg/ml). In addition, we observed that a few T cell clones were resistant to superantigenic restimulation in vitro. We conclude that when these types of T cells persist in the synovium, they play a role in the development of rheumatoid arthritis via a mechanism involving tumor necrosis factor alpha production.

Identification of murine T cells reactive with the bacterial superantigen Yersinia pseudotuberculosis-derived mitogen (YPM) and factors involved in YPM-induced toxicity in mice

We previously reported that Yersinia pseudotuberculosis-derived mitogen (YPM) acts as a superantigen to human T cells. In this study, we assessed the superantigenicity and toxicity of YPM using murine experimental models. YPM activated T cells to produce interleukin-2 in a major histocompatibility complex class II molecule-dependent manner. The T-cell blasts induced by YPM expressed T-cell receptor (TCR) beta-chain variable region (Vbeta)7, Vbeta8.1, Vbeta8.2 and Vbeta8.3. The injection of YPM into mice pre-sensitized with D-galactosamine induced lethal shock. This shock was blocked by the injection of monoclonal antibodies (mAbs) to CD4, TCR Vbeta7 plus Vbeta8, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma), but not by injection to CD8 or unrelated Vbeta. These results indicate that YPM-induced shock requires the presence of CD4+ T cells bearing TCR Vbeta7 and Vbeta8, and that endogenous TNF-alpha and IFN-gamma mediate the lethal effects.

Cytokines in alopecia areata: contrasting cytokine profiles in localized form and extensive form (alopecia universalis)

Recent studies have suggested that cytokines play a critical role in the pathophysiology of alopecia areata; however, no information is available regarding the difference in cytokine profiles in these patients. Serum levels of cytokines, including interferon gamma (IFN-gamma), tumor necrosis factor alpha, interleukin 1 alpha (IL-1 alpha), IL-2, IL-4, and IL-6, were measured using radioimmunoassay or enzyme-linked immunosorbent assay techniques in patients with the localized form and the extensive form (alopecia universalis). The serum levels of IL-1 alpha and IL-4 were significantly elevated in patients with the localized form. In contrast, the serum levels of IFN-gamma and IL-2 were significantly elevated in patients with the extensive form. These results indicate that immune responses in the localized form and the extensive form of alopecia areata are regulated by Th2 cytokines and Th1 cytokines, respectively.

Relation of green tea consumption to serum lipids and lipoproteins in Japanese men

Animal experiments have shown a hypocholesterolemic effect of green tea extracts. Only few epidemiological studies have addressed the relation between green tea consumption and serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). This paper examined the relation of green tea consumption to serum lipids and lipoproteins in 2,062 male self-defense officials in Japan, aged 49-55 years, who received a preretirement health examination at three hospitals of the Self-Defense Forces in 1991-1992. A self-administered questionnaire queried the consumption of green tea and a limited number of other dietary items as well as lifestyle characteristics. After adjustment for body mass index, waist-hip ratio, smoking, alcohol use, exercise, rank, and hospital, green tea consumption was inversely associated with serum levels of TC and LDL-C, but not with either high density lipoprotein cholesterol or triglycerides. Rice consumption was positively correlated with green tea consumption, and also was associated independently with lower levels of TC and LDL-C. Additional adjustment for rice, however, did not change the results. Daily drinking of 10 cups of green tea was associated with differences of 6.2 mg/dl in TC (95% confidence interval [CI] 0.4-12.1) and 6.2 mg/dl in LDL-C (95% CI 0.7-11.7). These findings of association of green tea with blood cholesterol hint at a possible causal relationship, which requires confirmation by further studies in humans using different methods.

Implantation of IL-2-containing osmotic pump prolongs the survival of superantigen-reactive T cells expanded in mice injected with bacterial superantigen

In the present study we investigated the mechanism of deletion of superantigen (sAg)-reactive T cells expanded in sAg-injected mice. In staphylococcal enterotoxin A (SEA)-injected mice, IL-2 activity in serum peaked at 1 to 3 h and the expression of IL-2R alpha-chain (IL-2R alpha) on SEA-reactive (V beta 3+, or V beta 11+) T cells peaked at 6 to 12 h after the injection. Expansion of V beta 3+ or V beta 11+ T cells peaked at 2 days after the injection when most of these T cells were IL-2R alpha negative, and IL-2 activity was not detected at all in serum, suggesting the involvement of IL-2 deprivation in the deletion of expanded T cells. Implantation of an osmotic pump containing human rIL-2 (IL-2 pump) prolonged the expanded states of V beta 3+ or V beta 11+ T cells in SEA-injected C57BL/6 mice and of V beta 8+ T cells in SEB-injected MRL +/+ and Fas Ag-defective MRL-Ipr/Ipr mice. Adult thymectomy did not change at all the effect induced by implantation of IL-2 pump. DNA fragmentation was blocked substantially in mice co-treated with SEA and IL-2 pump. In addition, CD4+ T cell blasts, obtained by in vitro stimulation with rIL-2 of splenic CD4+ T cells from mice co-treated with SEA and IL-2 pump, produced substantial amounts of IL-2 upon restimulation with SEA. These results indicate that deprivation of IL-2 is deeply involved in the deletion of expanded sAg-reactive T cells and their anergy induction in sAg-injected mice.

Implantation of IL-2-containing osmotic pump prolongs the survival of superantigen-reactive T cells expanded in mice injected with bacterial superantigen

In the present study we investigated the mechanism of deletion of superantigen (sAg)-reactive T cells expanded in sAg-injected mice. In staphylococcal enterotoxin A (SEA)-injected mice, IL-2 activity in serum peaked at 1 to 3 h and the expression of IL-2R alpha-chain (IL-2R alpha) on SEA-reactive (V beta 3+, or V beta 11+) T cells peaked at 6 to 12 h after the injection. Expansion of V beta 3+ or V beta 11+ T cells peaked at 2 days after the injection when most of these T cells were IL-2R alpha negative, and IL-2 activity was not detected at all in serum, suggesting the involvement of IL-2 deprivation in the deletion of expanded T cells. Implantation of an osmotic pump containing human rIL-2 (IL-2 pump) prolonged the expanded states of V beta 3+ or V beta 11+ T cells in SEA-injected C57BL/6 mice and of V beta 8+ T cells in SEB-injected MRL +/+ and Fas Ag-defective MRL-Ipr/Ipr mice. Adult thymectomy did not change at all the effect induced by implantation of IL-2 pump. DNA fragmentation was blocked substantially in mice co-treated with SEA and IL-2 pump. In addition, CD4+ T cell blasts, obtained by in vitro stimulation with rIL-2 of splenic CD4+ T cells from mice co-treated with SEA and IL-2 pump, produced substantial amounts of IL-2 upon restimulation with SEA. These results indicate that deprivation of IL-2 is deeply involved in the deletion of expanded sAg-reactive T cells and their anergy induction in sAg-injected mice.

[A case of effusive-constrictive pericarditis and its surgical treatment]

A 69-year-old male of effusive-constrictive pericarditis with a symptom of right heart failure was reported. The patient underwent surgery, as the medical treatment had not been effective. Through median spritting, very thickened pericardium and calcified epicardium of the right atrium, the right ventricle and the left ventricle were resected as largely as possible. In the space between the pericardium and epicardium, there existed yellow and thick fluid of about 50 ml which was evacuated. After surgery hemodynamic improvement was observed and the patient experienced a smooth postoperative course. Although pathological examinations revealed no special findings except the increased activity of adenosine deaminase of the yellow and thick fluid, tuberculosis was mostly suspected as the cause of the disease.

cDNA cloning of a mouse pituitary adenylate cyclase-activating polypeptide receptor

A cDNA clone for mouse pituitary adenylate cyclase-activating polypeptide (PACAP) receptor (PACAP-R) was obtained from the brain using reverse transcription-polymerase chain reaction (RT-PCR). The recombinant PACAP receptor expressed in COS cells bound PACAP with about 1000-times higher affinity than vasoactive intestinal polypeptide (VIP), and PACAP stimulated adenylate cyclase through the cloned PACAP receptor. The mouse PACAP receptor consists of 496 amino acids, contains seven transmembrane segments and has 98.4%, 93.0%, and 92.5% identity with the rat, bovine, and human PACAP-R, respectively.

A percutaneously accessible pulsatile left ventricular assist device: modified assist device type 5

To provide percutaneous access, a new circulatory assist system was developed. We call this newly developed system the modified assist device (MAD). The system is composed of a sac-type blood pump and cannula. Inflow and outflow valves are mounted in the apex and at the side wall 10 cm from the apex of the cannula, respectively. During systole, the blood is sucked from the left ventricle through the inflow valve of the cannula connected to the blood pump, and during diastole, the blood is ejected to the root of the aorta through the outflow valve. In vitro and in vivo evaluations of the pump performance were performed. The maximum flow rate of 1.9 L/min was obtained in the mock circulatory system. In our animal experiment, effective systolic unloading and diastolic augmentation were observed by activation of this system during regular sinus rhythm. In conclusion, the MAD-5 is thought to be percutaneously accessible and increases systemic and coronary flow.

Ofuji's disease and cytokines: Remission of eosinophilic pustular folliculitis associated with increased serum concentrations of interferon gamma

BACKGROUND AND OBJECTIVE

Eosinophilic pustular folliculitis (EPF) is a distinct inflammatory dermatosis of unknown etiology. The aim of this study is to evaluate the serum levels of cytokines in 3 patients with EPF before and after treatment with indomethacin.

RESULTS

Serum levels of interleukin 4 (IL-4) were elevated in patients with EPF. The remission of EPF was associated with increased serum concentrations of interferon gamma with no essential change of serum levels of IL-4.

CONCLUSION

These results suggest that subtle changes in serum levels of cytokines are involved in the remission of EPF and that indomethacin may provide the remission of EPF by altering cytokine production in patients with EPF.

Evidence for immunologic immaturity of cord blood T cells. Cord blood T cells are susceptible to tolerance induction to in vitro stimulation with a superantigen

T cell blasts resulting from stimulating human cord blood (CB) mononuclear cells (MC) and adult peripheral blood (APB) MC with a bacterial superantigen, toxic shock syndrome toxin-1 (TSST-1), and then with human rIL-2 were investigated for their reactions to restimulation with TSST-1. Expression of TCR V beta 2, which determines the potential reactivity to TSST-1 and of CD45RO, was increased in both TSST-1-induced CB and APB T cell blasts. Most preparations of the TSST-1-induced CB T cell blasts exhibited low or no production of IL-2 and IL-4 in response to restimulation with TSST-1, while the APB T cell blasts showed high responses. TSST-1-induced T cell blasts derived from APB T cells depleted of both CD45RO+ T cells and HLA class II+ T cells showed high IL-2 production in response to restimulation with TSST-1. TSST-1-induced CB T cell blasts generated in the presence of DR+ L cells with high accessory cell activity still showed a low response to restimulation with TSST-1. These results indicate that CB T cells are inherently highly susceptible to tolerance induction by bacterial superantigens, suggesting the immunologic immaturity of CB T cells.

Evidence for immunologic immaturity of cord blood T cells. Cord blood T cells are susceptible to tolerance induction to in vitro stimulation with a superantigen

T cell blasts resulting from stimulating human cord blood (CB) mononuclear cells (MC) and adult peripheral blood (APB) MC with a bacterial superantigen, toxic shock syndrome toxin-1 (TSST-1), and then with human rIL-2 were investigated for their reactions to restimulation with TSST-1. Expression of TCR V beta 2, which determines the potential reactivity to TSST-1 and of CD45RO, was increased in both TSST-1-induced CB and APB T cell blasts. Most preparations of the TSST-1-induced CB T cell blasts exhibited low or no production of IL-2 and IL-4 in response to restimulation with TSST-1, while the APB T cell blasts showed high responses. TSST-1-induced T cell blasts derived from APB T cells depleted of both CD45RO+ T cells and HLA class II+ T cells showed high IL-2 production in response to restimulation with TSST-1. TSST-1-induced CB T cell blasts generated in the presence of DR+ L cells with high accessory cell activity still showed a low response to restimulation with TSST-1. These results indicate that CB T cells are inherently highly susceptible to tolerance induction by bacterial superantigens, suggesting the immunologic immaturity of CB T cells.

Relationship of cigarette smoking, alcohol use, and dietary habits with sigmoid colon adenomas

The relationship between cigarette smoking, alcohol use, and dietary factors and the risk of adenomas of the sigmoid colon was examined in male self-defense officials who received a preretirement health examination at three Self-Defense Forces hospitals in Japan. In the comparison between 228 patients with sigmoid adenomas and 1484 control subjects with normal colonoscopy findings (> or = 60 cm from the anus), a clear dose-response relationship was observed between cigarette smoking and risk of adenoma. After adjustment for rank, body mass index, alcohol use, and physical activity as well as for hospital and survey season, the odds ratios (and 95% confidence intervals (CIs)) for the categories of 0, 1 to 399, 400 to 799, and 800 or more cigarette-years were 1.0, 2.1 (1.2 to 3.5), 2.8 (1.8 to 4.3), and 3.5 (2.1 to 5.8), respectively. Current alcohol drinkers tended to have an increased risk, but without a dose-response relation. Among four types of alcoholic beverages (shochu, sake, beer, and whiskey), only whiskey showed a weak association with risk of adenoma. None of the 13 dietary items studied (including meat and rice consumption) was measurably associated with adenoma risk. The present findings provide additional evidence that cigarette smoking is a risk factor for colon adenomas. It is inconclusive regarding alcohol intake's association with adenoma risk.

The relation of smoking, alcohol use and obesity to risk of sigmoid colon and rectal adenomas

We conducted a case-control study, using 429 cases with histologically confirmed sigmoid adenoma, 75 cases with rectal adenoma, and 3101 controls showing normal colonoscopy at least up to 60 cm from the anus. The subjects were male Self-Defense Forces personnel aged 48-56 who received a retirement health examination including a routine sigmoid- or colonoscopy. Lifestyle characteristics were ascertained by a self-administered questionnaire. Smoking in the recent past (< or = 10 years preceding the colonoscopy) and smoking in the remote past (> 10 years before the colonoscopy) were both significantly associated with risk of sigmoid adenoma but not with rectal adenoma as a whole. After reciprocal adjustment for smoking in the two periods, only smoking in the recent past was associated with both sigmoid colon and rectal adenomas. Odds ratios (OR) of sigmoid adenoma (and 95% confidence interval) for the categories of 0, 1-150, 151-250 and > or = 251 cigarette-years were 1.0 (reference), 1.9 (1.3-2.8), 2.1 (1.4-3.0) and 3.0 (1.9-4.7), respectively (P for trend < 0.01), and those for rectal adenoma were 1.0 (reference), 1.2 (0.4 3.2), 3.5 (1.4-8.5) and 2.0 (0.6 6.7), respectively (P for trend = 0.03). Alcohol use was significantly positively associated with sigmoid adenoma, and insignificantly associated with rectal adenoma. Body mass index was significantly positively associated with sigmoid adenoma, especially large ones. No such association was found for rectal adenoma. These findings suggest that smoking, especially in the recent past, and alcohol use are common risk factors for sigmoid colon and rectal adenomas while obesity may be exclusively related to the growth of sigmoid adenoma.

Tumor necrosis factor production by human T-cells stimulated with bacterial superantigens

Tumor necrosis factor (TNF) production from T-cells stimulated with superantigenic exotoxins, staphylococcal enterotoxin B and streptococcal pyrogenic exotoxin A was investigated in the presence of cells bearing distinct isotypes of HLA class II molecules. The main T-cell subset for TNF production was investigated in parallel. Similarly high levels of TNF production were induced upon stimulation with the toxins in the presence of DR+ or DQ+ cells, but only marginal levels of TNF production were induced in the presence of DP+ cells. Although both CD4+ T-cells and CD8+ T-cells produced TNF-alpha and TNF-beta in response to toxin stimulation in the presence of HLA class II+ cells, the former T-cell subset was the major source of producers of TNF-alpha and TNF-beta.

Relation of waist-hip ratio to glucose tolerance, blood pressure, and serum lipids in middle-aged Japanese males

OBJECTIVE

To investigate whether waist-hip ratio (WHR) influences glucose tolerance, blood pressure, and serum lipids independently of body mass index (BMI).

DESIGN

Cross-sectional study.

SUBJECTS

2,228 male self-defense officials aged 49-55 years in Japan.

MEASUREMENTS

BMI, WHR, serum lipids, systolic and diastolic blood pressure, and glucose tolerance status according to World Health Organization (WHO) criteria.

RESULTS

Adjustment was made for smoking, alcohol use, physical activity, and inter-hospital variation in statistical analysis. Adjusted odds ratios of non-insulin-dependent diabetes mellitus (NIDDM) were progressively increased with increasing levels of WHR, but not BMI. Both BMI and WHR were independently positively associated with impaired glucose tolerance to almost the same degree. Adjusted means of blood pressure, total cholesterol, and triglycerides were almost linearly increased with increasing levels of both BMI and WHR, and high-density lipoprotein cholesterol was progressively decreased. Although the associations of BMI and WHR with blood pressure and serum lipids attenuated after mutual adjustment for each, BMI was less influenced by WHR than vice versa, except for triglycerides.

CONCLUSION

WHR is an important contributor not only to NIDDM but also to impaired glucose tolerance, blood pressure, and serum lipids, although the associations of WHR with blood pressure and serum lipids were generally weaker than those of BMI, except for triglycerides.

New version of flow-transformed pulsatile total artificial heart with no electrical switching valve

The flow-transformed pulsatile total artificial heart (FTPTAH) is a new pulsatile total artificial heart that consists of a single continuous flow rotary blood pump and blood flow switching valves. It can perfuse the pulmonary and the systemic circulation alternately with pulsatile flow. A new version of the FTPTAH, which consists of one undulation pump (UP), 4 jellyfish valves, and a compensatory chamber, has been proposed. The UP is a reversible continuous flow blood pump, and flow transformation is caused by switching the direction of the motor rotation so that no electrical flow switching valve is needed. A prototype model could perfuse alternately pulmonary and systemic circulation with 3.0 L/min in a mock circulation. Unoxygenated blood in the UP at the end of pulmonary circulation will be stored in the compensatory chamber by shifting a flexible membrane to the direction of the left atrium (LA); therefore, the blood is not sent to the systemic circulation.

Development of a new apparatus to observe microcirculation chronically in continuous flow blood pump research

To observe microcirculation chronically is an important key to the successful evaluation of the continuous flow blood pump. In this study, we succeeded in developing a new apparatus by which microcirculation could be observed chronically without a microscope in a conscious animal. The apparatus utilizes a charge coupled device (CCD). A thin living tissue, such as mesentery, is put directly on a highly integrated CCD and is lit up through the tissue with a light-emitting diode (LED). The vascular nets in the tissue are projected onto the CCD like a contact photograph, which is then sent to a television screen and which can be used to analyze their motion and function. A 0.5-inch CCD having 250,000 pixels was used in this study. The cover glass of the CCD was removed, and a fiber optic plate was fixed onto the surface of the CCD for the tissue to be able to contact with the apparatus surface without clearance. The CCD as well as the LED were molded with epoxy resin for electrical insulation. The apparatus was 35 mm wide and 12 mm high with a micro stand for an LED, which can be easily implanted into an animal. The apparatus was implanted into a rabbit for 12 h. The configuration of arterioles and venules, tens of micrometers in diameter, and their motions in subcutaneous tissue could be observed.

Basic study to develop the undulation pump for practical use: antithrombogenicity, hemolysis, and flow patterns inside the pump

The undulation pump (formerly called the precessional displacement pump) is a continuous flow displacement-type blood pump that is being developed as an implantable total artificial heart. A new undulation pump was developed for chronic use and was examined with animal experiment and flow visualization studies. In the animal experiment using a left ventricular bypass in goats, severe hemolysis occurred. After driving for 12 h, thrombus formation inside the pump was found. In the flow visualization studies, the flow pattern showed that the flow inside the pump was a very complicated turbulent flow. Improvement of hemolysis and thrombus formation is important to realize implantable total artificial hearts using undulation pumps.

Gallstone disease among Japanese men in relation to obesity, glucose intolerance, exercise, alcohol use, and smoking

BACKGROUND

Risk factors for gallstones are not fully understood, especially in men. Obesity and other risk factors for gallstone disease were investigated in Japanese men based on gallbladder ultrasonography.

METHODS

Forty-one men with gallstones, 31 with postcholecystectomy state, and 2044 with a normal gallbladder were identified among 2228 men aged 49-55 years who received a retirement health examination at three hospitals of the Japan Self-Defense Forces between 1991 and 1992. Glucose tolerance was determined with a 75-g oral glucose tolerance test.

RESULTS

Body mass index was not associated with gallstones, although it was significantly, positively related to postcholecystectomy. Waist to hip circumference ratio tended to be weakly associated with gallstones. Diabetes mellitus was associated only with postcholecystectomy. Smoking, alcohol intake, and physical activity were not measurably related to either gallstones or postcholecystectomy.

CONCLUSIONS

The present study failed to substantiate an association of gallstone risk with either obesity or any other risk factor. Further observation is needed in view of the limited study power.