Risk factors associated with persistent postoperative hypertension in Cushing's syndrome

The aim of the present study was to assess the long-term results of adrenalectomy and to evaluate potential risk factors for the persistence or recurrence of hypertension. Forty-five patients with Cushing's syndrome caused by benign cortisol-producing adrenocortical adenomas were evaluated before and for a period of 1 year after surgical cure. When the patients were classified into two groups according to whether their preoperative BP was more (HBP group) or less (NBP group) than 140/90 mmHg, the BP level was found to be continuously higher in the HBP group than in the NBP group during the year after surgery. This finding suggests that the preoperative BP level in Cushing's syndrome may be a determinant factor for persistent hypertension after surgery (P<0.05). In addition, a correlation was found between postoperative BP level and duration of hypertension (P<0.05), but no relationships were found between postoperative BP levels and other factors, including age, BMI, tumor size, serum cortisol, aldosterone, potassium, total cholesterol, or glucose levels. The above findings indicate that intensive control of preoperative BP to maintain it below 140/90 mmHg with antihypertensive medication is a very important means of improving prognosis for postoperative BP. Immediate diagnosis and surgical treatment to reduce the duration of hypertension are also crucial for the long-term BP prognosis.

Transcriptional regulation of steroid receptor coactivator-1 (SRC-1) in glucocorticoid action

Diverse mechanisms of steroid receptor action have been clarified in recent years, as a consequence of the discovery of multiple coactivators. Among them, steroid receptor coactivator-1 (SRC-1) is a member of the p160 coactivator families, which are 160 kDa proteins that interact with steroid receptors in a hormone-sensitive manner. Since coactivators function as transcriptional power boosters, subtle changes in coactivator expression levels in certain cells markedly change of receptor-mediated transcriptional activity. Expression of the glucocorticoid receptor (GR) has been shown to be autoregulated in glucocorticoid action, i.e., GR is downregulated by its cognate ligand, indicating that this autoregulation of GR may protect target cells against excessive hormone action. In the present study, we examined whether coactivator expression levels are also regulated by glucocorticoids. Among several coactivators, the SRC-1 mRNA level was downregulated by dexamethasone treatment in rat tissues, such as liver, heart, kidney, stomach, and cerebrum, in vivo. We also demonstrated dexamethasone-mediated downregulation of SRC-1 mRNA and its protein levels in rat renal mesangial cells in vitro. These results suggest that ligand-mediated downregulation of SRC-1 is crucial in the physiology of glucocorticoid action.

Polymorphism in the promoter of lipopolysaccharide receptor CD14 and ischemic cerebrovascular disease

BACKGROUND AND PURPOSE

A growing amount of evidence suggests that infectious and inflammatory processes may be involved in the initiation of arteriosclerosis, but the mechanisms are conceivably multifactorial and complex. Two European groups have recently demonstrated that a C(-260)-->T polymorphism in the promoter of the CD14 lipopolysaccharide receptor may be a risk factor for coronary artery disease (CAD). The T allele of this polymorphism reportedly increases the expression of CD14 and may be involved in atherogenesis. In the present study we investigated a possible association between the C(-260)-->T polymorphism in the CD14 promoter and the occurrence of symptomatic ischemic cerebrovascular disease (CVD).

METHODS

Genotype frequencies of the C(-260)-->T polymorphism in the CD14 promoter were determined in 235 patients with CVD, as confirmed by brain CT and/or MRI, and 309 age- and sex-matched control subjects.

RESULTS

The distribution of genotypes was as follows: CVD patients, T:/T: 24.3%, C:/T: 53.2%, and C:/C: 22. 6%; controls, T:/T: 26.9%, C:/T: 50.2%, and C:/C: 23.0%. There was no significant difference between the CD14 promoter genotypes of the CVD patients and the controls (chi(2)=0.601, P:=0.741). We also measured the concentration of serum soluble CD14 and the density of membranous CD14 on monocytes in the CVD patients, but the polymorphism was not associated with either the concentration of soluble CD14 or the density of membranous CD14 (P:=0.358, P:=0.238, respectively).

CONCLUSIONS

Our results indicate that the C(-260)-->T polymorphism in the CD14 promoter is not associated with an increased risk for CVD.

Possible role of cytotoxic T cells in acute liver injury in hepatitis C virus cDNA transgenic mice mediated by Cre/loxP system

A line of hepatitis C virus (HCV) transgenic mice was established previously that was mediated by Cre/loxP system using HCV cDNA, including core, E1, E2 and NS2 genes. Intravenous infection of a recombinant adenovirus that expresses Cre DNA recombinase (AxCANCre) induced HCV structural protein expression in the liver of transgenic mice. HCV core protein production and transgene recombination in the mouse liver were serially evaluated after AxCANCre infusion. Core proteins were expressed efficiently and transgene was almost completely recombined in the liver of mice after 3 days and then the levels of both core protein production and transgene recombination decreased continuously for 28 days. However, 30.6% of the transgene recombination remained at 28 days and only 2.7% of core production remained at 28 days after infection. Compared with nontransgenic controls, the serum alanine aminotransferase levels in transgenic mice were significantly higher 10, 14, and 21 days after adenovirus infection. Histological scoring also indicated severe pathological changes in the liver of transgenic mice after adenovirus infection. AxCANCre infusion increased CD8+ lymphocyte infiltration into the liver of transgenic mice compared with that of non-transgenic controls. Furthermore, cytotoxic T lymphocytes (CTLs) isolated from transgenic mice during liver injury were specific for the HCV proteins. These results suggest that HCV structural proteins expressed in the liver of transgenic mice enhanced liver injury. HCV-specific CTLs may be to enhance hepatitis. Thus, the present HCV transgenic mouse model provides a useful model of liver injury due to HCV, and the host immune response may play a pivotal role(s) in the pathogenesis of HCV.

Amplification of pepleomycin-mediated DNA cleavage and apoptosis by unfused aromatic cations

An important approach to improve chemotherapy of members of the bleomycin (BLM) family of antibiotics is to find compounds (amplifiers) that enhance the activity of BLM-mediated DNA cleavage and apoptosis. Using a DNA-sequencing technique and pulsed field gel electrophoresis, we have investigated whether BLM-mediated cleavage of isolated and cellular DNA is amplifed by three compounds (RW-12, LS-20, 1S-5Me) which have a conformationally flexible, unfused polyaromatic system and cationic side chain in the molecules. RW-12 enhanced most effectively both pepleomycin (PEM)-induced cytotoxicity and apoptosis. The order of the maximum enhancing effect of amplifiers on PEM-mediated DNA damage is RW-12 > LS-20 > 1S-5Me. RW-12 amplified PEM-mediated DNA cleavage most effectively not only in vitro but also in cultured cells. We have reported that the order of the DNA binding constants of these compounds is RW-12 > LS-20 > 1S-5Me. In this study, we found a good correlation between PEM-mediated cleavage of isolated DNA and cellular DNA. These results suggest that BLM amplifiers bind to DNA and by doing so enhance drug-mediated DNA degradation, ultimately leading to apoptosis. The present study on amplifiers of anticancer agents shows a novel approach to the potentially effective anticancer therapy.

Structure of IL-10 and its role in autoimmune exocrinopathy

Cytokines are implicated in the pathogenesis of a variety of autoimmune disorders. Whether the presence of cytokines is primary or secondary and the extent to which these factors may contribute to the development and progression of clinicopathologic alterations in these disorders remain largely unknown but are highly important questions. Our research focuses on evaluating these issues by using a transgenic approach to direct the constitutive expression of cytokines to epithelial cells in the intact exocrine glands of mice. Our recent studies have focused on the potential of the regulatory cytokine IL-10 produced by type 2 T-helper cells to inhibit inflammation and the development of autoimmue diseases. Using targeted introduction of this molecule into the exocrine gland epithelial cells, we found that IL-10 induced apoptosis of glandular tissues destruction and lymphocyte infiltration consisting primarily of Fas-ligand+ CD4+ T cells, as well as in vitro upregulation of FasL expression on T cells. These results suggest that IL-10 is necessary and sufficient for exocrine gland dysfunction in the transgenic mice. This article discusses recent advances in IL-10 and its role in the pathological conditions of autoimmune exocrinopathy.

Site-selective DNA alkylation of GG steps by naphthaldiimide derivatives possessing enantiomeric epoxide

We have synthesized an enantiomeric pair of novel DNA alkylating agents consisting of a naphthaldiimide intercalator and a chiral epoxy side chain. These naphthaldiimide derivatives have high DNA binding affinity and selectively alkylate 5'G of the GG steps for (S)-epoxide and 3'G for (R)-epoxide.

Comparison of fatal coronary heart disease occurrence based on population surveys in Japan and the USA

BACKGROUND

Although vital statistics have indicated large Japanese-American differences in mortality rates for coronary heart disease (CHD), the magnitude of difference has not been documented well using comparable validation of cause of death.

METHODS

Population-based fatal CHD data were compared between the Oita Cardiac Death Survey, Japan and the Atherosclerosis Risk in Communities (ARIC) Study, USA. Both studies (population: Oita City 198 093; the ARIC comunities 286 820) identified possible fatal CHD events (International Classification of Diseases, Ninth Revision [ICD-9]: 410-414, 250, 401-402, 427-429, 440, and 798-799) among residents aged 35-74 years during 1992-1993. Comparable criteria for classifying cause of death were applied. Sex-specific, age-adjusted mortality rates of CHD were calculated by place of death.

RESULTS

In all, 330 deaths in Oita and 1398 in the ARIC communities had eligible ICD-9 death certificate codes; CHD codes (ICD-9 410-414) comprised 30.6% of investigated deaths in Oita and 58.6% in ARIC. For men, the non-validated rate ratio for CHD deaths (ARIC:Oita City) was 5.9 (95% CI : 4.2-8.5), which fell to 4.7 (95% CI : 3.5-6.4) with validation and inclusion of sudden deaths within one hour of onset as fatal CHD. For women, the overall non-validated rate ratio was 4.6 (95% CI : 2.8-7.6), which fell to 3.9 (95% CI : 2.4-6.3) with validation and but there was little further change when the sudden deaths were added.

CONCLUSIONS

Our results suggest that differences in fatal CHD rates between Japanese and Americans were not as large as suggested by vital statistics when events were validated and sudden deaths were included.

Incidence of human papillomavirus 16 and 18 infection and p53 mutation in patients with oral squamous cell carcinoma in Japan

The purpose of this study was to investigate the prevalence of human papillomaviruses (HPVs) 16 and 18 infection, and p53 mutation in oral squamous cell carcinomas (SCCs) in Japanese patients. Our results showed a higher incidence of HPV16 and 18 infections than previous studies because we combined the findings of a consensus polymerase chain reaction (PCR), restriction fragment length polymorphism by using the restriction enzyme digestion of the PCR products and Southern blot hybridization. Each HPV16 and 18 E6/E7 DNA was detected in 9 (20%) and 25 (54%) of 46 samples. The p53 mutation in the exons from 5 to 8 were detected in 20 out of 46 samples (43%) by a PCR-single strand conformation polymorphism analysis. There was a significant relationship between HPV16 and the p53 mutation (P =0.02) suggesting that HPV16 infection has a mutagenic effect in oral SCC. However, neither HPV infection nor p53 mutation influenced survival.

Evaluation of flow volume and flow patterns in the patent false lumen of chronic aortic dissections using velocity-encoded cine magnetic resonance imaging

In 21 patients with chronic aortic dissections and proven patent false lumens, the flow volume and flow patterns in the patent false lumens was evaluated using velocity-encoded cine magnetic resonance imaging (VENC-MRI) and the relationship between the flow characteristics and aortic enlargement was retrospectively examined. Flow patterns in the false lumen were divided into 3 groups: pattern A with primarily antegrade flow (n=6), pattern R with primarily retrograde flow (n=3), and pattern B with bidirectional flow (n=12). In group A, the rate of flow volume in the false lumen compared to the total flow volume in true and false lumens (%TFV) and the average rate of enlargement of the maximum diameter of the dissected aorta per year (deltaD) were significantly greater than in groups R and B (%TFV: 74.1+/-0.07 vs 15.2+/-0.03 vs 11.8+/-0.04, p<0.01; deltaD: 3.62+/-0.82 vs 0 vs 0.58+/-0.15 mm/year, p<0.05, respectively). There was a significant correlation between %TFV and deltaD (r=0.79, p<0.0001). Evaluation of flow volume and flow patterns in the patent false lumen using VENC-MRI may be useful for predicting enlargement of the dissected aorta.

Importance of sex and age factor in assessing family history of stroke

Incidence of stroke differs between men and women and it increases nearly exponentially with age. Therefore, assessment of family history of stroke disregarding sex and age of family members results in bias or misclassification. In this study the effects of sex and age on the positivity of the past history were analyzed numerically. Sex- and age-specific proportion of a positive history of stroke among 24,007 family members was obtained from a questionnaire survey of 2,316 high school students. By analyzing the sex- and age-specific proportion with the logistic regression model odds ratios resulting from sex and age difference were estimated. The odds ratio for sex difference was 2.458 (95% confidence interval: 2.067-2.924) and odds ratio for age difference was 1.064 (95% confidence interval: 1.058-1.070). This indicated that a positive history of stroke was 2.458 times higher in male members than in female members of the same age and that a positive history increased by (1.064)y, where y was age difference in years. Potential bias or misclassification resulting from disregarding sex and age can be substantial. Some measures to control for sex and age of family members are required in assessing the family history.

Mechanisms of neonatal tolerance induced in an animal model for primary Sjögren's syndrome by intravenous administration of autoantigen

Neonatal exposure to autoantigen is believed to induce effective antigen-specific T-cell tolerance in experimental models of autoimmunity. We have identified 120 kDa alpha-fodrin autoantigen in an animal model for primary Sjögren's syndrome (SS), that has been determined as a candidate autoantigen in both an animal model and the patients with primary SS. We demonstrate here that neonatal injection of autoantigen induce relevant tolerance when treated with intravenous (i.v.) administration within 24 h after birth, but not with i.v. injection after the thymectomy or with intraperitoneal injection. Autoantigen-specific T-cell response was significantly reduced in mice induced neonatal tolerance, and the activation markers of splenic CD4+ T cells were down-regulated in mice treated with neonatal administration. Because we detected that neonatal i.v. injection of autoantigen prevented Th1 response, it is possible that the autoantigen administration within 24 h after birth induce regulatory T cells that had a protective effect against Th1-mediated autoimmune diseases. These results indicate that the prevention of the spontaneous anti-120 kDa alpha-fodrin response in vivo, by tolerization of the autoantigen-reactive T cells, blocked the development of autoimmune lesions in an animal model for primary SS.

Combined medical and surgical treatment of severe vernal keratoconjunctivitis

PURPOSE

We report the efficacy of an alternative method of treatment for vernal keratoconjunctivitis (VKC) that consists of excision of the palpebral conjunctiva followed by supratarsal injection of corticosteroid and five times daily topical application of 0.05% cyclosporine A (CsA) and cromolyn sodium.

METHODS

We evaluated 10 patients with severe treat-resistant VKC with corneal complications. The patients were evaluated for symptoms and for signs, including conjunctival changes, corneal limbal infiltrates, vascularization, reduction of epitheliopathy, meibomitis, visual acuity, intraocular pressure, and pathologic evaluation, before and after treatment.

RESULTS

All patients showed marked improvement after 2 weeks of treatment. The symptoms (P <.01), signs (P <.02), and the visual acuity of all patients (P <.01) had significantly improved following treatment. Histological examination showed significant inflammatory cell decreases 4 weeks after surgery (P <. 05).

CONCLUSION

Surgery plus topical drug therapy may be useful in treating patients with very severe VKC.

Effects of body weight control on changes in blood pressure: three-year follow-up study in young Japanese individuals

Numerous epidemiological studies have shown a close relationship between obesity and hypertension. However, there have been few reports on the relationship between changes in the body weight and blood pressure of lean to normal-weight young subjects. The purpose of this study was to investigate the effects of body weight control on blood pressure in lean to obese young Japanese individuals in a 3-year follow-up study. University students (3,558 males and 1,418 females, aged 18.6+/-0.8 in 1994) were classified into 4 groups according to the baseline body mass index (BMI), and were followed up for 3 years. Among male students, changes in body weight were significantly correlated with changes in blood pressure during the 3 years in all 4 BMI groups, and the correlation coefficient was larger in the group with higher baseline BMI. Positive correlations between changes in body weight and changes in heart rate were noted only in the obese and mildly-obese groups. Also in female students, positive correlations were observed between changes in body weight and changes in blood pressure in lean to obese groups. However, no correlations between changes in body weight and changes in heart rate were noted in any of the female groups. To summarize, close correlations were observed between changes in body weight and those in blood pressure during the 3 years in both male and female university students. These findings suggest the importance of body weight control not only in obese but also in normal to mildly-obese young subjects in reducing or preventing an increase in blood pressure. There could be, however, a gender difference in the effects of body weight change on heart rate.

Autoantigen-specific CD4+CD28low T cell subset prevents autoimmune exocrinopathy in murine Sjögren's syndrome

Organ-specific autoimmune exocrinopathy resembling Sjögren's syndrome (SS) that spontaneously develops in NFS/sld mutant mice thymectomized 3 day after birth is dependent on Th1-type CD4+ T cells. We previously reported that a cleavage product of 120-kDa alpha-fodrin may be an important autoantigen in the pathogenesis of SS in both an animal model and the patients. We demonstrate that in an animal model of SS with overt exocrinopathy, a unique CD4+ T cell subset expressing CD28low is dramatically increased in spleen cells before the disease onset, but that the CD4+ T cells of diseased mice were virtually all CD28high. We found that the spleen cells in these mice before the disease onset showed a significant increase in autoantigen-specific T cell proliferation. Analysis of in vitro cytokine production by spleen cells indicated, before the disease onset, severely impaired production of IL-2 and IFN-gamma in the animal model, whereas high levels of IL-4 were observed. Expression of cytokine genes, including IL-4, IL-10, and TGF-beta, was detected in FACS-sorted CD4+CD28low T cells by RT-PCR analysis. Transfer of CD4+CD28low T cells into the animal model actually prevented the development of autoimmune lesions including autoantibody production. These results suggest that a CD4+CD28low T cell subset that is continuously activated by an organ-specific autoantigen may play a regulatory role in the development of organ-specific autoimmune disease in an animal model of SS.

Using one rotary blood pump to produce separate pulsatile circulations in the upper and lower halves of the body

Separate systemic circulations with pulsatile flow were obtained using 1 rotary blood pump as a left ventricular assist device. The outlet of the pump was divided into 2 conduits, 1 connected to the upper half of the body and the other connected to the lower half. An electric actuator that clamped the 2 outlet conduits alternately provided pulsatile flows. An in vitro experiment showed that the pulsatility phases of the upper and lower halves of the body were complementary with pulsatile flow, and an in vivo experiment showed that controlled flow distributions of continuous flows could be obtained.

Development of a miniature undulation pump for the distributed artificial heart

Research of the distributed artificial heart is important not only to acquire the means of individual organ perfusion but also to clarify the characteristics of the organ and the mechanism of blood distribution. To investigate the distributed artificial heart, the miniature undulation pump was developed. The outer diameter and the thickness of the developed pump were 38 mm and 11 mm, respectively. The priming volume of the pump was 3.2 ml. The total size including the motor unit was 38 mm in diameter and 32 mm in length. The total weight was 67.5 g. The total volume was 27.5 ml. The pump was driven with pulse width modulation by using a 1 chip motor controller. More than 5 L/min of continuous output could be obtained. The results showed that the developed miniature undulation pump system had enough performance for individual organ perfusion.

Nontraditional risk factors for coronary heart disease incidence among persons with diabetes: the Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

Major risk factors explain much of the excess risk for coronary heart disease produced by diabetes, but nontraditional factors may also relate to incident coronary heart disease.

OBJECTIVE

To examine the association of traditional and nontraditional risk factors with incidence of coronary heart disease in adults with diabetes.

DESIGN

Prospective cohort study.

SETTING

The Atherosclerosis Risk in Communities (ARIC) Study.

PARTICIPANTS

1676 middle-aged persons who had diabetes but no history of prevalent coronary heart disease.

MEASUREMENTS

Multiple risk factors were recorded at baseline. Follow-up was from 1987 through 1995.

RESULTS

186 participants developed incident coronary heart disease events during follow-up. As expected, the incidence of coronary heart disease in participants with diabetes was associated positively with traditional risk factors (hypertension, smoking, total cholesterol level, and low high-density lipoprotein [HDL] cholesterol level). After adjustment for sex, age, ethnicity, and ARIC field center, incident coronary heart disease was also significantly associated with waist-to-hip ratio; levels of HDL3 cholesterol, apolipoproteins A-I and B, albumin, fibrinogen, and von Willebrand factor factor VIII activity; and leukocyte count. However, after adjustment for traditional risk factors for coronary heart disease, only levels of albumin, fibrinogen, and von Willebrand factor; factor VIII activity; and leukocyte count remained independently associated with coronary heart disease (P < 0.03). The relative risks associated with the highest compared with lowest groupings of albumin, fibrinogen, factor VIII, and von Willebrand factor values and leukocyte count were 0.64 (95% CI, 0.44 to 0.92), 1.75 (CI, 1.12 to 2.73), 1.58 (CI, 1.02 to 2.42), 1.71 (CI, 1.11 to 2.63), and 1.90 (CI, 1.16 to 3.13), respectively. Adjustment for diabetes treatment status attenuated these associations somewhat.

CONCLUSIONS

Levels of albumin, fibrinogen, and von Willebrand factor; factor VIII activity; and leukocyte count were predictors of coronary heart disease among persons with diabetes. These associations may reflect 1) the underlying inflammatory reaction or microvascular injury related to atherosclerosis and a tendency toward thrombosis or 2) common antecedents for both diabetes and coronary heart disease.

Cleavage of parallel-stranded DNA duplex by peplomycin metal complexes

Peplomycin-mediated degradation of parallel-stranded (ps) duplex was investigated. It was found that Co- and Fe-peplomycins degraded ps DNA duplex by 4'-hydrogen abstraction at 5'-GPy (pyrimidine) site in a similar manner to that of antiparallel B-DNA. While the orientation of two strands of ps and B-form DNA duplexes are reversed, peplomycin metal complex can bind to ps DNA duplex to cause oxidative DNA damage. These results indicate that peplomycin metal complex mainly interacts with one strand which is damaged.

Amplification of bleomycin-induced DNA cleavage by pyrrole triamide

We investigated the amplification of bleomycin-induced DNA cleavage by synthetic pyrrole triamide (PyPyPy) using 32P-labeled DNA fragments obtained from human genes. Peplomycin, a kind of bleomycins, plus Fe(II) caused DNA cleavage at the 5'-GC-3' and 5'-GT-3' sequences (damaged bases are underlined). The addition of PyPyPy enhanced the cleavage at cytosine and thymine residues 3' to consecutive guanines, particularly at the 5'-GGGGC-3' and 5'-GGGGT-3' sequences. These results suggest that PyPyPy binds to DNA to induce its conformational change, resulting in alteration of the site specificity and amplification of DNA cleavage. The present study on amplifiers of antitumor drugs would show a novel approach to the establishment of more effective chemotherapy.

DNA HOMO as a new landmark for nucleic acid properties. ab initio calculations and experimental mapping

Of the non-covalent binding forces in DNA-drug or DNA-protein interaction, electrostatic interaction, stacking interaction, hydrogen bonds and hydrophobic effect have been well established. However, only a few HOMO-LUMO interaction in DNA have been reported. We examined the ab initio calculations of B-DNA duplex 5-mers. Based on the calculated results, we investigated the mapping of HOMO experimentally and found that DNA cleavage patterns with Co(II) and BPO (Benzoyl peroxide) were in good agreement with the ab initio calculation results.

Synthesis of pyrrole-imidazole-duocarmycin polyamide and its sequence selective DNA alkylation

The new solid phase synthesis of sequence-specific DNA alkylating polyamides containing segment A of Du86 (Duo), N-methylimidazole (Im) and N-methylpyrrole (Py) amino acids is described. New monomer building block N-carboxylmethyl Py (Pyc) was synthesized from 2-methylpyrrolecarboxylate by eight steps. After normal coupling of FMOC-protected-Im and -Py monomer, the deprotection of silyl group generates free carboxylic acid. Introduction of various types of functional groups on solid support will be presented.

Reversible photoligation of DNA via 5-vinyldeoxyuridine

We report a novel non-enzymatic template-directed reversible photoligation of oligodeoxyribonucleotides (ODNs). In this photoligation system, a modified ODN containing 5-vinyldeoxyuridine at 5'-end reacts by photoirradiation at 366 nm with cytosine and thymine at the 3'-end of another ODN in the presence of a complementary template to yield a ligated ODN quantitatively. The ligated ODN can be split site-selectively to regenerate the parent ODN by photoirradiation at 302 nm.

Detection of viable myocardium by dobutamine stress tagging magnetic resonance imaging with three-dimensional analysis by automatic trace method

The present study attempted to detect the viability of myocardium by quantitative automatic 3-dimensional analysis of the improvement of regional wall motion using an magnetic resonance imaging (MRI) tagging method. Twenty-two subjects with ischemic heart disease who had abnormal wall motion on echocardiography at rest were enrolled. All patients underwent dobutamine stress echocardiography (DSE), coronary arteriography and left ventriculography. The results were compared with those of 7 normal volunteers. MRI studies were done with myocardial tagging using the spatial modulation of magnetization technique. Automatic tracing with an original program was performed, and wall motion was compared before and during dobutamine infusion. The evaluation of myocardial viability with MRI and echocardiography had similar results in 19 (86.4%) of the 22 patients; 20 were studied by positron emission tomography or thallium-201 single photon emission computed tomography for myocardial viability, or studied for improvement of wall motion following coronary intervention. The sensitivity of dobutamine stress MRI (DSMRI) with tagging was 75.9% whereas that of DSE was 65.5%. The specificity of DSMRI was 85.7% (6/7) and that of DSE was 100% (7/7). The accuracy of DSMRI was 77.8% (28/36) and that of DSE 72.2% (26/36). DSMRI was shown to be superior to DSE in terms of evaluation of myocardial viability.

Results of animal experiments using an undulation pump total artificial heart: analysis of 10 day and 19 day survival

An undulation pump is a special rotary blood pump in which rotation of a brushless DC motor is transformed to an undulating motion by a disc in the pump housing attached by means of a special link mechanism. In the blood pump, a closed line between the disc and housing moves from the inlet to the outlet by this undulating disc motion, which sucks and pushes the blood from the inlet to the outlet. Because the same phenomena occurs at both sides of the disc, a continuous flow is obtained when the motor rotational speed is constant. The pump flow pattern can be easily changed from continuous flow to pulsatile flow by controlling the motor drive current pattern. A seal membrane made of segmented polyurethane protects the blood from invading the link mechanism as well as the motor. UPTAH is fabricated with two undulation pumps and two brushless DC motors. Its size is 75 mm in diameter and 80 mm long, and it has one of the great advantage of no compliance chamber required in the system. UPTAHs were implanted under cardiopulmonary bypass (CPB) into the chest cavities of 16 goats, each weighing between 41 and 72 kg. No anticoagulant and antiplatelet agent was used after the surgery. The left atrial pressure was automatically controlled to prevent its elevation and sucking of the atrial wall into the atrial cuff. The following results were obtained: (1) UPTAHs fit well into all the goats; (2) the longest survival was 19.8 days, the cause of death was bleeding from the aortic anastomosis; (3) No thrombus was observed in the blood pump despite no anticoagulant use. Hemolysis depended upon the length of CPB during surgery. When CPB time was within 2 hours, hemolysis level returned to baseline within a few days of the surgery. UPTAH is a promising implantable TAH, because of its small size and easy controllability.

Cloning and characterization of a human brain Na(+)-independent transporter for small neutral amino acids that transports D-serine with high affinity

We isolated a cDNA for the human homologue of system asc transporter Asc-1 from human brain. The encoded protein designated as hAsc-1 (human Asc-1) exhibited 91 % sequence identity to mouse Asc-1. Consistent with mouse Asc-1, hAsc-1 required 4F2 heavy chain for its functional expression in Xenopus oocytes. hAsc-1 exhibited the properties of amino acid transport system asc which transports small neutral amino acids in a Na(+)-independent manner. hAsc-1 transported D-serine at high affinity with a K(m) value of 22.8 microM. In brain, 2.0 kb mRNA was highly expressed. hAsc-1 gene was mapped to human chromosome 19, region q12-q13.1. Because of the high-affinity transport with the K(m) value close to the physiological concentration of D-serine, together with the high levels of expression in brain, hAsc-1 is proposed to play significant roles in the D-serine mobilization in brain.

Experimental studies of stereotactic laser balloon hyperthermic treatment

BACKGROUND AND OBJECTIVE

The hyperthermic treatment of small malignant brain tumors in basal ganglia and other eloquent cortical areas was investigated with a stereotactic Nd:YAG laser balloon unit.

STUDY DESIGN/MATERIALS AND METHODS

An Ultra Line fiber (Heraeus Laser Sonics, CA) was inserted into a 6 F silicone balloon catheter, which caused the laser beam to be directed 80 degrees laterally. The balloon was inflated with physiologic saline to make the tumor tissue surrounding the laser fiber hypoxic. The hypoxia enhances the thermal effect on the tumor. The laser power was set at 5 watts (W) and a computer, programmed with specific parameters using feedback control was used to maintain the tissue 10 mm distant from the laser fiber at a temperature of 45 degrees C. Forty five minutes of hyperthermic treatment was applied to an implanted subcutaneous glioma in a rat.

RESULTS/CONCLUSION

The thermally induced damaged in the tumor appeared as a fan-shape lesion extending at a 100 degrees angle from the laser beam axis. The entire tumor could be treated by rotating the laser fiber in the balloon catheter.

Severe destructive autoimmune lesions with aging in murine Sjögren's syndrome through Fas-mediated apoptosis

When we evaluated the age-associated changes in autoimmune exocrinopathy in a NFS/sld murine model for primary Sjögren's syndrome (SS), severe destructive autoimmune lesions developed in the salivary and lacrimal glands in the aged mice, compared with those observed in the younger model. We detected a decreased secretion of saliva and tear flow in the aged group. A significant increase of TUNEL(+)-apoptotic epithelial duct cells in the salivary glands was detected in the aged SS animal model. A higher proportion of mouse salivary gland cells bearing Fas was found in the aged group, whereas no significant changes were seen on tissue-infiltrating CD4(+) T cells bearing FasL in the salivary glands from young and aged mice. We detected an increased cleavage product of organ-specific autoantigen, 120-kd alpha-fodrin, in the aged salivary gland tissues on immunoblotting, and an increase in serum autoantibody production against 120-kd alpha-fodrin by enzyme-linked immunosorbent assay. An increase in the proliferative response of splenic T cells against organ-specific autoantigen was observed, whereas nonspecific concanavalin A responsiveness was decreased in the aged mice. In addition, a decrease in Fas expression was found on splenic CD4(+) T cells in the aged mice, and anti-Fas mAb-stimulated apoptosis was down-regulated on CD4(+) T cells. These results indicate that age-associated dysregulation of CD4(+) T cells may play a crucial role on acceleration of organ-specific autoimmune lesions in a murine model for primary SS through Fas-mediated apoptosis.

Participation in school sports clubs and related effects on cardiovascular risk factors in young males

The effects of belonging to sports clubs on male high school students was evaluated. The relationships between the type and extent of school-based exercise were examined in conjunction with percent body fat, blood pressure (BP), and other key metabolic parameters. A total of 264 male Japanese high school students (age range: 17-18 years old) were studied. Percent body fat was measured and blood was collected in the fasting state during a routine health check. Subjects were divided into two groups. The exercise (E) group (n=150) included students who had belonged to a sports club during the past 2 years. The non-exercise (NE) group (n=114) included students who did not belong to a sports club during the past 2 years. The body mass index was significantly greater in group E (21.7 +/- 2.3 (SD) kg/m2) than in group NE (20.7 +/- 2.6 kg/m2, p < 0.01). However, the percent body fat in group E (13.6 +/- 3.4%) was significantly lower than that in group NE (14.9 +/- 3.8%, p < 0.01). The diastolic BP and heart rate in group E (64 +/- 7 mmHg, 70 +/- 11/min) were significantly lower in group E than in group NE (66 +/- 8 mmHg, p < 0.05; 76 +/- 14/min, p < 0.01). The serum triglyceride level was significantly lower, and the HDL cholesterol level was higher in group E than in group NE. The homeostasis model assessment (HOMA) index, used as an index of insulin resistance, was similar in the two groups. However, the level of the HOMA index was significantly lower among the 62 subjects in group E who preferred highly dynamic exercise (1.50 +/- 0.46) than it was among those in group NE (1.66 +/- 0.49, p < 0.05). Results indicate that belonging to sports clubs influences the BP and lipid profiles of adolescent males, as well as their percent body fat. In view of the reduction of cardiovascular risk factors, it is recommended that even young males practice regular exercise, especially aerobic exercise.

C242T polymorphism of NADPH oxidase p22 PHOX gene and ischemic cerebrovascular disease in the Japanese population

BACKGROUND AND PURPOSE

Superoxide has been implicated in the pathogenesis of ischemic stroke and atherosclerosis. NADPH oxidase, a major source of superoxide generation in neutrophils and the vascular system, plays a critical role in ischemic injury and atherogenesis. Recently, an association between the C242T polymorphism of p22 PHOX, an essential component of NADPH oxidase, and coronary artery disease (CAD) has been reported in several studies. To investigate the relationship between the C242T polymorphism of p22 PHOX and ischemic cerebrovascular disease (CVD), we conducted a case-control study.

METHODS

We recruited 226 CVD patients (atherothrombotic infarction, lacunar infarction, and transient ischemic attack) and 301 control subjects and analyzed C242T polymorphism of p22 PHOX by detection of restriction fragment length polymorphism.

RESULTS

The TC+TT genotype frequencies in the CVD group and control group were 21.7% and 13.3%, respectively, and the prevalence of the TC+TT genotype was significantly higher in the CVD patients (chi(2)=6.477, P=0.01, OR 1.81, 95% CI 1.15 to 2.86). Analysis by CVD subtypes showed that the OR for the TC+TT genotype was higher in the CVD patients with atherothrombotic infarction than in those with lacunar infarction and transient ischemic attack.

CONCLUSIONS

The C242T polymorphism of the NADPH oxidase p22 PHOX gene is a novel pathogenetic risk factor for CVD.

Analysis of hemodynamic response with 1/R control on biventricular bypass goat

A conductance and arterial pressure based method (1/R control) to determine the cardiac output (CO) of a total artificial heart (TAH) was developed to provide a central nervous system with control over the output of TAH. In order to clarify the deference in hemodynamic response between natural heart and 1/R control, biventricular bypass was introduced in the goat. After 2 pneumatically driven sac-type blood pumps were connected to the natural heart, the pulmonary artery was totally clamped to acquire 100% right heart bypass, and the ascending aorta was stenosed to acquire about 60 to 90% left heart bypass; 1/R control was performed substituting the output of the right artificial heart for the CO. The results demonstrated that stable control could be achieved. A discrepancy was often seen between the pulse rate (PR) of the artificial heart and the heart rate (HR) in absolute value. However, the relative changes of PR were quite similar to that of HR for the most part, indicating that the responses of 1/R control were the duplication of natural cardiac responses in normal daily activity.

Angiotensin II antagonists for hypertension: are there differences in efficacy?

We compared the antihypertensive efficacy of available drugs in the new angiotensin-II-antagonist (AIIA) class. The antihypertensive efficacy of losartan, valsartan, irbesartan, and candesartan was evaluated from randomized controlled trials (RCT) by performing a metaanalysis of 43 published RCT. These trials involved AIIA compared with placebo, other antihypertensive classes, and direct comparisons between AIIA. A weighted-average for diastolic and systolic blood pressure reduction with AIIA monotherapy, dose titration, and with addition of low-dose hydrochlorothiazide (HCTZ) were calculated. Weighted-average responder rates were also determined. The metaanalysis assessed a total of 11,281 patients. The absolute weighted-average reductions in diastolic (8.2 to 8.9 mm Hg) and systolic (10.4 to 11.8 mm Hg) blood pressure reductions (not placebo-corrected) for AIIA monotherapy were comparable for all AIIA. Responder rates for AIIA monotherapy were 48% to 55%. Dose titration resulted in slightly greater blood pressure reduction and an increase in responder rates to 53% to 63%. AIIA/hydrochlorothiazide combinations produced substantially greater reduction in systolic (16.1 to 20.6 mm Hg) and diastolic (9.9 to 13.6 mm Hg) blood pressure reductions than AIIA monotherapy and responder rates for AIIA/HCTZ combinations were 56% to 70%. This comprehensive analysis shows comparable antihypertensive efficacy within the AIIA class, a near-flat AIIA-dose response when titrating from starting to maximum recommended dose, and substantial potentiation of the antihypertensive effect with addition of HCTZ.

CTLA4IgG gene delivery prevents autoantibody production and lupus nephritis in MRL/lpr mice

MRL/MP-lpr/lpr (MRL/lpr) mice spontaneously develop an autoimmune syndrome closely resembling systemic lupus erythematosus (SLE) in humans, characterized by hypergammaglobulinemia, various autoantibody production, and the development of fatal glomerulonephritis. We have previously demonstrated that systemic administration of soluble form of CTLA4IgG prevented autoantibody-related diseases in MRL/lpr mice. To test the potential protective effects of CTLA4IgG gene delivery on the development of lupus nephritis, we injected MRL/lpr mice with a recombinant adenovirus vector containing CTLA4IgG gene, Adex1CACTLA4IgG (AdCTLA4IgG). It was demonstrated that a single administration of intravenous injection of AdCTLA4IgG into MRL/lpr mice resulted in almost complete amelioration of lupus nephritis.

Presence of sonographically detectable parathyroid glands can predict resistance to oral pulsed-dose calcitriol treatment of secondary hyperparathyroidism

Oral pulsed-dose calcitriol administration has been shown to be effective therapy for patients with secondary hyperparathyroidism. However, this effect is not consistently observed in the clinical setting. This study was undertaken to examine whether enlarged parathyroid glands can serve as a clinical marker that predicts the suppressive effect of calcitriol. Thirty-five patients undergoing chronic hemodialysis (HD) were examined (age, 51.9 +/- 14.9 years; duration of HD, 72.0 +/- 56.0 months). Based on the volume of parathyroid glands measured using an ultrasonographic scanner, patients were divided into two groups: 15 patients with undetectable parathyroid glands (ND group) and 20 patients with detectable parathyroid glands (D group; mean volume of parathyroid glands, 261. 9 +/- 347.5 mm(3)). No significant differences were found in serum ionized calcium (Ca(++)) or parathyroid hormone (PTH) levels before calcitriol administration between the two groups. For each patient, 8 microg of calcitriol was administered orally at the end of the HD session, and the changes in serum PTH levels were determined 44 hours after dosing. No significant differences were found between the two groups in serum Ca(++) levels. However, a significant decrease in serum PTH levels was observed in the ND group, whereas no significant changes were found in the D group. The results of the study show that the suppressive effect on PTH through calcitriol therapy was reduced in patients with detectable enlarged parathyroid glands. This may indicate that the size of parathyroid glands is one factor determining the therapeutic potential of pulsed-dose calcitriol administration for secondary hyperparathyroidism.

Continuous monitoring of cerebrospinal fluid acid-base balance and oxygen metabolism in patients with severe head injury: pathophysiology and treatments for cerebral acidosis and ischemia

INTRODUCTION

Continuous monitoring of cerebral acid-base balance and oxygen metabolism has been introduced in neurointensive care settings. The hypothesis of this study utilizing multimodal neuromonitoring modalities is that hyperventilation and hypothermia improve cerebral acidosis through prevention of cerebral ischemia aggravation in patients with severe head injury.

PATIENTS AND METHODS

Continuous monitoring of cerebrospinal fluid (CSF) pH, PCO2, HCO3-, base excess (BE), PO2, SO2, temperature, lactate and pyruvate (La and Py) measurements were conducted in 8 patients with severe head injury. Temperature-corrected CSF parameters were correlated with those in the jugular blood including oxygen saturation (SjO2), regional oxygen saturation (rSO2), intracranial pressure (ICP) and cerebral perfusion pressure (CPP), jugular blood temperature (Tjb), and endtidal PCO2 (PetCO2). Therapeutic significance of hyperventilation and hypothermia was evaluated.

RESULTS

1) CSF acidosis was observed in all cases (minimum pH 6.59-7.17) due to increased CSF PCO2 and/or decreased CSF HCO3- and tended to associate with abnormal ICP and/or CPP or ischemic episodes indicated by CSF PO2 and SO2, rSO2, and/or SjO2 during monitoring. 2) It was more obvious in CSF than in jugular blood that increased PCO2, La and Py, and/or decreased HCO3- resulted in decreased BE and pH. 3) Decreased CSF PO2 and SO2 only correlated with severe CSF acidosis. 4) Hyperventilation: Decreased PetCO2 did not always closely correlate with CSF PCO2 decrease and CSFpH increase. 5) Hypothermia: There were negative correlations of Tjb with CSF pH and SO2 in all cases, though correlation coefficients were not always high.

CONCLUSIONS

CSF acidosis caused by increased CSF PCO2, La and Py, and/or decreased HCO3- tended to associate with abnormal ICP and CPP, and desaturation indicated by CSF SO2, rSO2, and/or SjO2. Hypothermia rather than hyperventilation tends to improve cerebral acidosis and ischemia.

Association between platelet glycoprotein Ibalpha genotype and ischemic cerebrovascular disease

BACKGROUND AND PURPOSE

Platelets play pivotal roles in the development of ischemic cerebrovascular disease (CVD). The platelet glycoprotein (GP) Ib/IX/V complex is a receptor for von Willebrand factor, which plays a major role in the initial phase of platelet activation under high shear stress conditions. This study was designed to investigate the association between a genetic variation of this receptor and the prevalence of CVD.

METHODS

Two hundred patients with ischemic CVD, as confirmed by brain CT and/or MRI, and 317 age- and sex-matched control subjects without clinical evidence of CVD or cardiovascular disease were analyzed for their genotype frequencies of the (145)Thr/Met dimorphism of the alpha-chain of GPIb (GPIbalpha).

RESULTS

Genotypes with (145)Met (T/M and M/M) were more frequently found in the CVD patients (26.5%) than in control subjects (14.2%, P=0.0005). The genotype effect was more obvious in those <60 years of age or without acquired cardiovascular risk factors. The odds ratio for nonsmoking women <60 years of age was 10. 6 (95% confidence intervals, 2.2 to 51.7). Although the number of patients studied was small (n=24), transient ischemic attack showed the highest odds ratio (4.3, P=0.0004), followed by lacunar infarction (OR=2.2, P=0.0024) and atherothrombotic infarction (OR=1. 5, P=0.3143). Logistic regression analysis revealed that the presence of Met-allele was independently associated with CVD.

CONCLUSIONS

Our study suggests that the platelet GPIbalpha genotype is a genetic risk factor for ischemic CVD.

Treatment with anti-CD86 costimulatory molecule prevents the autoimmune lesions in murine Sjögren's syndrome (SS) through up-regulated Th2 response

Intraperitoneal administration with anti-CD86 (B7.2) MoAb into the murine model for primary SS in NFS/sld mutant mice resulted in dramatically inhibitory effects on the development of autoimmune lesions, while no significant effects were observed when the mice were administered with anti-CD80 (B7.1) MoAb. We found that spleen cells in the murine SS model treated with anti-CD86 MoAb showed a significant impairment of autoantigen-specific T cell proliferation. T cell activation markers (CD44high, CD45RBlow, Mel-14low) were significantly down-regulated in the spleen cells gated on CD4 in anti-CD86-treated mice. We detected a higher level of cytokine production of IL-4 from splenic T cells in anti-CD86-treated mice, but not of IL-2, and interferon-gamma (IFN-gamma), compared with those in the anti-CD80- and PBS-treated SS model. Moreover, serum autoantibody production against alpha-fodrin autoantigen was almost entirely suppressed in anti-CD86-treated mice. These data provide strong evidence that in autoimmune exocrinopathy resembling SS in NFS/sld mutant mice, the CD86 costimulatory molecule plays a crucial role in the initiation and subsequent progression of Th1-mediated autoimmunity in the salivary and lacrimal glands.

New method for scanning of single-nucleotide polymorphisms (SNPs): recognition of guanine-guanine mismatches by dimeric naphthyridine

Dimeric naphthyridine was designed and synthesized as a novel ligand that specifically binds to G-G mismatch, one of four SNP types. In the presence of dimeric naphthyridine, CD spectra of the G-G mismatch containing duplex noticeably changed, being accompanied by the induced CD at 300-350 nm, whereas no CD spectral change was observed for normal duplex. DNaseI footprinting titration indicated a selective binding of dimeric naphthyridine to the G-G mismatch with a dissociation constant of 53 nM.

Site-specific oxidation at GG and GGG sequences in double-stranded DNA by benzoyl peroxide as a tumor promoter

Benzoyl peroxide (BzPO), a free-radical generator, has tumor-promoting activity. As a method for approaching the mechanism of tumor promoter function, the ability of oxidative DNA damage by BzPO was investigated by using (32)P-labeled DNA fragments obtained from the human p53 tumor suppressor gene and c-Ha-ras-1 protooncogene. BzPO induced piperidine-labile sites at the 5'-site guanine of GG and GGG sequences of double-stranded DNA in the presence of Cu(I), whereas the damage occurred at single guanine residues of single-stranded DNA. Both methional and dimethyl sulfoxide (DMSO) inhibited DNA damage induced by BzPO and Cu(I), but typical hydroxyl radical ((*)OH) scavengers, superoxide dismutase (SOD) and catalase, did not inhibit it. On the other hand, H(2)O(2) induced piperidine-labile sites at cytosine and thymine residues of double-stranded DNA in the presence of Cu(I). Phenylhydrazine, which is known to produce phenyl radicals, induced Cu(I)-dependent damage at thymine residues but not at guanine residues. These results suggest that the BzPO-derived reactive species causing DNA damage is different from (*)OH and phenyl radicals generated from benzoyloxyl radicals. BzPO/Cu(I) induced 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation in double-stranded DNA more effectively than that in single-stranded DNA. Furthermore, we observed that BzPO increased the amount of 8-oxodG in human cultured cells. Consequently, it is concluded that benzoyloxyl radicals generated by the reaction of BzPO with Cu(I) may oxidize the 5'-guanine of GG and GGG sequences in double-stranded DNA to lead to 8-oxodG formation and piperidine-labile guanine lesions, and the damage seems to be relevant to the tumor-promoting activity of BzPO.