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Asymptomatic or silent atrial fibrillation (AF) has long been a clinical problem due to the incidence of ischemic stroke. A method is needed to predict the development of silent AF before the occurrence of ischemic stroke. This study was focused on the symptoms of AF, especially palpitation, in pacemaker patients. We assessed the hypothesis that absence of palpitation during rapid ventricular pacing could be a predictor of future onset AF being asymptomatic.In this study, we assessed the presence of symptoms during RV pacing and AF symptoms on 145 pacemaker patients at the outpatient clinic by VVI pacing at 120 ppm. The relationship between symptoms during RV pacing and symptom during AF was assessed. The predictive value of absence of symptom during RV pacing on AF being asymptomatic was assessed.Of 145 patients, 74 had previous AF episode. Among the AF patients, absence of symptom during VVI pacing was associated with AF being asymptomatic.Of 145 patients, 71 had no previous AF events. There were 14 patients who had new-onset AF or atrial flutter (AFL) after the device implantation. Four of the 14 patients (28.6%) were symptomatic during first AF/AFL episode, and 10 (71.4%) were asymptomatic during first-onset AF. All ten patients who were asymptomatic during cardiac pacing test were asymptomatic during their initial episodes of AF as well.This study showed that absence of symptoms during rapid ventricular pacing was associated with first-onset AF being asymptomatic.

Robust localization of self-reproducing autocatalytic chemistries is a key step in the realization of heritable and evolvable chemical systems. While autocatalytic chemical reaction networks already possess attributes such as heritable self-reproduction and evolvability, localizing functional multispecies networks within complex primitive phases, such as coacervates, has remained unexplored. Here, we show the self-reproduction of the Azoarcus ribozyme system within charge-rich coacervates where catalytic ribozymes are produced by the autocatalytic assembly of constituent smaller RNA fragments. We systematically demonstrate the catalytic assembly of active ribozymes within phase-separated coacervates—both in micron-sized droplets as well as in a coalesced macrophase, underscoring the facility of the complex, charge-rich phase to support these reactions in multiple configurations. By constructing multispecies reaction networks, we show that these newly assembled molecules are active, participating both in self- and cross-catalysis within the coacervates. Finally, due to differential molecular transport, these phase-separated compartments endow robustness to the composition of the collectively autocatalytic networks against external perturbations. Altogether, our results establish the formation of multispecies self-reproducing reaction networks in phase-separated compartments which in turn render transient robustness to the network composition.

We demonstrate that a recombinase ribozyme achieves multiple functions in the same reaction network: self-reproduction, iterative elongation and circularization of other RNAs, leading to synthesis of diverse products predicted by a kinetic model. This shows that key mechanisms can be integrated and controlled toward Darwinian evolution in RNA reaction networks., The integration of self-reproduction and diversification mechanisms in RNA reaction networks paves the way for experimental tests of prebiotic evolution.

Objective: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin K antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years. Methods: Individual patient data analysis from seven prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (

Emergence and maintenance of polymers with complex sequences is a major question in the study of origins of life. To answer this, we studied a model polymerization reaction, where polymers are synthesized by stepwise ligation from two types of monomers, catalyzed by a long polymer as a template. Direct stochastic simulation and dynamical systems analysis revealed that the most dominant polymer sequence in a population successively changes against the flow rate of monomer to the system. The slower the flow, the more is the complex sequence selected. We discuss the relevance of this kinetic selection of sequence by the non-equilibrium flow rate to the origin of complex polymers., Comment: 12 pages, 12 figures

The emergence of replicases that can replicate themselves is a central issue in the origin of life. Recent experiments suggest that such replicases can be realized if an RNA polymerase ribozyme is divided into fragments short enough to be replicable by the ribozyme and if these fragments self-assemble into a functional ribozyme. However, the continued self-replication of such replicases requires that the production of every essential fragment be balanced and sustained. Here, we use mathematical modeling to investigate whether and under what conditions fragmented replicases achieve continued self-replication. We first show that under a simple batch condition, the replicases fail to display continued self-replication owing to positive feedback inherent in these replicases. This positive feedback inevitably biases replication toward a subset of fragments, so that the replicases eventually fail to sustain the production of all essential fragments. We then show that this inherent instability can be resolved by small rates of random content exchange between loose compartments (i.e., horizontal transfer). In this case, the balanced production of all fragments is achieved through negative frequency-dependent selection operating in the population dynamics of compartments. This selection mechanism arises from an interaction mediated by horizontal transfer between intracellular and intercellular symmetry breaking. The horizontal transfer also ensures the presence of all essential fragments in each compartment, sustaining self-replication. Taken together, our results underline compartmentalization and horizontal transfer in the origin of the first self-replicating replicases., 14 pages, 4 figures, and supplemental material

A biological system consists of a variety of polymers that are synthesized from monomers, by catalysis that exists only for some long polymers. It is important to elucidate the emergence and sustenance of such autocatalytic polymerization. We analyze here the stochastic polymerization reaction dynamics, to investigate the transition time from a state with almost no catalysts to a state with sufficient catalysts. We found an optimal volume that minimizes this transition time, which agrees with the inverse of the catalyst concentration at the unstable fixed point that separates the two states, as is theoretically explained. Relevance to the origin of life is also discussed., 6 pages, 7 figures

The purpose of this project is to examine several numerical simulation techniques which have been used for the development of 400 mm silicon single crystals. The temperature distribution in all of the hot zone (HZ) regions is calculated by global heat transfer analysis. The thermoelastic stress within a crystal is calculated based on the crystal temperature. The melt convection or argon gas flow is simultaneously solved by global heat transfer analysis. In this paper, we report our design and experiment results for an 18-in HZ configuration for 150 mm crystals. This configuration can be enlarged to 36-in. HZ for 300 mm crystal or 36-in. HZ for 400 mm crystals. For each of these HZ configurations, a global heat transfer numerical simulation is performed. These results show that a degradation in the thermal damage to the quartz crucible, the argon gas flow pattern, and the thermoelastic stress at the growth interface, are predicted to be functions of HZ size — the larger the configuration, the greater the degradation. In order to reduce the thermoelastic stress, the shape of the growth interface should be controlled to be as flat as possible

The purpose of this project is the development of a crystal supporting system (CSS) for silicon crystals with large diameters of 400 mm. Amongst the many technical problems the one that the Super Silicon Crystal Research Institute Corp. (SSi) has directed its energies is to support a weight in excess of the ability of the Dash neck to support this weight. After considering various solutions, we developed a CSS that mechanically supports the silicon subsidiary cone formed between the Dash neck and crystal shoulder. Using this method, an approximately 400 kg ingot was successfully grown from 500 kg of molten silicon in a 36-in. quartz crucible. We confirmed that the CSS mechanism worked correctly through the entire crystal growth process. This paper presents some of the anticipated problems in the mechanical supporting method and the corresponding solutions. Finally, results from real crystal growth to test and verify machine operation are reported.

Since 1996, we have been investigating the crystal growth of 400-mm silicon crystals as the next generation of silicon wafer size after 300 mm. The first dislocation-free crystal was grown in 1998, and the heaviest dislocation free crystal ever, weighing 413 kg, was safely grown in 2000 using a crystal suspending system. In this paper, we describe an experimental study on large-diameter silicon crystal growth, its growth conditions, and the crystal properties of 400-mm silicon crystals.

In the SSi project, the growth technologies for 400 mm silicon single crystals have been investigated by several numerical simulation techniques, global heat transfer analysis in a Czochralski (CZ) furnace, structural analysis, analysis of fluid dynamics for melt convection and argon gas flow. In this paper, the bake out process, the initial meltdown process, the dip process and the body process are numerically simulated, respectively. According to these results, the numerical simulation is very useful and necessary for development of the CZ furnace, designing of hot zone structures and the prediction of experimental results.

The intermediate results of Super Silicon Crystal project are introduced to serve a production platform of 400 mm silicon. SSi has already installed a 400 mm CZ furnace. Raw materials are sufficiently applicable for 36 inch hot zone. We discuss a contact part between a crystal suspending system and a subsidiary cone. A successful handling system for a fragile quartz crucible and for a heavy silicon crystal is also described. A wire saw for 400 mm wafers has already been installed in SSi and sliced 400 mm wafers are demonstrated. For 400 mm epitaxial wafers, we describe pretreatment for epitaxial growth at low temperature.

We examine the origins of metal impurities in Czochralski (Cz) single-crystal silicon in order to develop improved crystal purification techniques. We calculate the mass of metal impurities incorporated into molten silicon from each origin during crystal growth and estimate the concentration of impurities in the molten silicon and single-crystal silicon. To confirm these results, we analyze a sample of the residual melt after crystal growth. By comparing the calculated and experimental results, it is shown that the main origins of Al and Ni are probably the quartz crucible and polysilicon, respectively, while Fe originates from both. The calculated concentration of Fe and Ni in single-crystal silicon is 10 8 – 10 9 cm −3 , and that of Al is 10 11 – 10 12 cm −3 . We confirm that the concentrations of Fe and Ni can be reduced by using high-purity silicon as a raw material.

During a five-year period, the International Atomic Energy Agency supported a Coordinated Research Programme (CRP) to investigate the quantitative relationship between internal body burdens of a number of elements of environmental health significance and their respective concentrations in hair. The use of nuclear-related analytical techniques, such as neutron activation analysis, X-ray fluorescence, particle-induced X-ray emission and radiotracers, was emphasized. One aspect of the CRP focused on studies in man, using autopsy cases, of mineral distribution in five tissues, i.e. liver, kidney, lung, brain and bone in addition to hair, and the elements of primary importance were As, Cd, Cu, Hg, Pb, Se and Zn. Emphasis was placed on analytical quality assurance. Hair and internal tissue samples were obtained from subjects from Bulgaria, China, the former German Democratic Republic, Hungary, Japan, Norway and Sweden.

The aim of this study was to evaluate the operative techniques of total arch replacement, the clinical results and the survival curves of patients following this procedure.Since December 2001, 92 patients have undergone surgical treatment for aortic dissection and aneurysm. The total aortic arch replacement was performed in 24 of these patients. There were 16 men and 8 women, and the age range was 42 to 81 years with a mean age of 59.4 years. As the operative technique for total arch replacement, we used the 4-branched prosthetic graft, selective cerebral perfusion (SCP), continuous cold blood cardioplegia (CCBC), and open distal anastomosis under circulatory arrest. The combined operations were coronary bypass grafting in 4 patients, aortic valve suspension in 1 patient and a Bentairs procedure in 1 patient. Eleven (73.3%) patients with acute dissection required emergency operation.The hospital mortality rate was 25% (6 of the 24 patients). The causes of death were multiple organ failure (MOF) due to renal and mesenteric ischemia in 3 patients, cerebral infarction in 2 patients, myonephropathic metabolic syndrome (MNMS) in 1 patient, respectively. The data concerning extracorporeal circulation was 204+/-53 min in total pump time, 136+/-43 min in aortic cross clamp time, 83+/-14 min in SCP time and 48+/-10 min in circulatory arrest time, respectively. The long-term result in actuarial survival rate was 76% for 5 years.We consider the technique of total arch replacement using 4-branched prosthetic graft, SCP, CCBC, and open distal anastomosis is a useful operative method in patients with aortic aneurysm.

Humic substances, naturally occurring highly polymerized organic compounds, exist widely in the water and soil environments. It has been known that the humic substances affect the fate of micro-organic pollutants (e.g. intake, accumulation, movement, degradation, toxicity, etc.). Of these, the effect of humic substances on the intake into biota (i.e. living cell) is one of the most important. In this research, the effects of co-existing humic substances on the intake of micro-organic pollutants into aquatic biota were experimentally evaluated. The humic acid filtrate using a 3,000 Da ultra-filtration membrane was used. Two PAHs (i.e. pyrene and phenanthrene) were used as micro-organic pollutants. Liposome for simulating living cell membrane was synthesized in the laboratory, and used for investigating the intake of micro-organic pollutants into aquatic biota precisely. The batch experiment results (PAHs onto humic acid, humic acid into liposome, and PAHs into liposome (K(lipw))) led to the fact that the sorption of PAHs into liposome is suppressed apparently by binding with humic acid in the aqueous phase. This suggests that the accumulation and/or toxicity of micro-organic pollutants is retarded by humic substances in the actual aqueous environment. Moreover, the experimental results indicated that the sorption into liposome (i.e. liposome/water partition coefficient (K(lipw))) could be a better parameter for estimating the intake of micro-organic pollutants into aquatic biota than n-octanol/water partition coefficient (K(ow)) in the aqueous environment.

A 36-year-old man was admitted to our hospital because of impalement injury due to a downwards fall upon some reinforced steel rods. An emergency operation was performed using percutaneous cardiopulmonary support (PCPS). The steel rods were taken out in the operating room. The heart, great vessels, vertebrae, and spinal cord were not involved in the impalement wounds. We performed a bronchoplasty of the torn and separated right main bronchus, and repaired the impaled left lung without any pulmonary resection. He recuperated without sequelae.

Recently life expectancy has become longer and longer. The purpose of this study was to analyse whether arterial surgery for patients over 80 years of age is advisable.During the last 14 years, 527 patients, 50 of whom were over 80 and 477 of whom were under 80 years of age, received graft replacement or bypass surgery. They suffered from ruptured abdominal aortic aneurysm (R-AAA, n=21), non-ruptured abdominal aortic aneurysm (N-R AAA, n=133) or arteriosclerosis obliterans (ASO, n=373). Complications such as cerebrovascular disease, ischemic heart disease, respiratory and kidney dysfunction, and risk factors for ASO were also checked.All of the patients over 80 with R-AAA (n=3/3) and 50% of the patients under 80 with R-AAA (n=9/18) died during their stay in the hospital. However, none of the N-R AAA patients over 80 (n=0/7) and only one of the 126 N-R AAA patients (0.8%) under 80 died. For the patients over 80 with ASO, the graft patency rate was better than the patients survival rate. There were no age-specific factors that should condemn arterial surgery for patients over 80 years of age.Arterial surgery should not be ruled out on the basis of age alone.

We used fibrin adhesive for the treatment of pulmonary air leak after pneumonectomy to sealing effect of fibrin adhesive which was classified by application and obtained the following results. 98 patients with pulmonary air leak were randomly allocated to the double layer group and spray group. The following were investigated between the double layer group and spray group. 1) size and dose of fibrin adhesive, 2) airway pressure where pulmonary air leak was observed before and after application, 3) duration of postoperative pulmonary air leak, 4) degree of postoperative pulmonary air leak, and 5) postoperative complication. The dose of fibrin adhesives was significantly smaller, the mean duration of postoperative pulmonary air leak was significantly shorter and the degree of postoperative pulmonary air leak was significantly more slight in the spray group than in the double layer group. In addition, the sutured part was examined before and after application of fibrin adhesives with a scanning electron microscope. Fibrin nets were formed more uniformly by the spray method than by the double layer method. From these investigations it is concluded that since the appliance for the spray method is improved and easily used and fibrin nets are formed uniformly by this method, the spray method is useful for the prophylaxis of pulmonary air leak.

The metabolism of toborinone, (+/-)-6-[3-(3,4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-quin - olinone, a novel inotropic agent, was studied in rats and dogs after intravenous administration. Chemical structures of the 13 metabolites were characterized by direct-probe FAB/MS and field desorption/MS, LC/FAB/MS, and various NMR measurements. After intravenous dosing of 10 mg/kg [14C]toborinone, fecal and urinary recoveries of the 14C dose were approximately 70% and 26-30%, respectively, in both rats and dogs. The predominant component of radioactivity was the unchanged toborinone in every biological specimen in rats and dogs. Although unchanged toborinone was predominantly observed, toborinone underwent extensive conjugations with glucuronic acid, sulfate, and glutathione, either directly or following phase I reaction. Metabolites resulting from oxidative N-C cleavage were minor both in number and in quantity in every biological specimen in rats and dogs. In rats, toborinone underwent O-demethylation to form M-7 and successive phase it reaction to yield the glucuronide M-1 and the sulfoconjugate M-2, and deconjugation to yield M-7, which was a primary metabolite accounted for 35.67% of the radioactivity excreted in the feces by 48 hr. Conjugates M-1 and M-2 were the major metabolites in rat plasma. In dogs, toborinone was metabolized via mercapturic acid pathway to yield the primary metabolites, cysteine conjugates M-10 and M-11 that accounted for 19.10% and 6.70% of the radioactivity excreted in the feces by 48 hr and that were detected species specifically in dogs. The glutathione conjugate M-13, which was isolated from in vitro incubations using dog liver, led us to consider a possible mercapturic acid pathway from the parent compound to M-10. Metabolites in dog plasma and those in urine in both rats and dogs were minor in quantity. The metabolic pathways of toborinone in rats and dogs are proposed herein.

A) Noninvasive Diagnosis 1. Doppler ultrasonic techniques to get vascular image, to measure blood flow velocity and to hear blood flow sounds. 2. Plain X-ray photography to evaluate arterial wall calcification. 3. Plain and contrast enhanced X-ray computed tomography to assess arterial wall calcification, luminal stenosis and occlusion. 4. Three-dimensional spiral computed tomographic angiography to image the vascular lumen stereographycally. 5. Magnetic resonance angiography for the diagnosis and follow up. 6. Thermography at rest and after loading low temperature and/or exercise. B) Invasive Diagnosis 1. Vascular endoscope to evaluate arterial lumen directly. 2. Intravascular ultrasound imaging to assess the arterial wall architecture. C) Radioisotopic Diagnosis 1. RI angiography. 2. Single photon emission computed tomography to diagnose blood flow distribution in ischemic ulcer and/or hip muscle. In conclusion, it is very important to think always what one is seeing and what one wants to see. There is no single diagnostic procedure which enables one to diagnose everything.

An 81-year-old man was admitted to our hospital with a complaint of dysuria. He had had a right hypogastric aneurysm repaired three years earlier. Physical examination showed a distended soft abdomen and tender mass about the size of a child's head but no murmur was heard over the mass. An excretory urogram (DIP) showed left hydronephrosis and no excretion from the right kidney. Computerized tomography (CT) showed urinary bladder compressed by the mass on the upper right back side. Cystography showed that the large mass occupied the pelvic region with calcification and communicated with the bladder. After a few days, an operation for the aneurysm was undertaken by the surgical department. Although bilateral ureterolysis was possible, a resection of the aneurysm could not be done. The aneurysm was injected with fibrin adhesive and a bilateral nephrostomy was performed. The renal function has been stable and the size of the aneurysm has remained unchanged for 9 months after the surgery.

Red blood cells parasitized with Theileria sergenti were cultured in vitro for a short period in microplate wells. Addition of [3H]hypoxanthine to cultures enabled us to titrate the intraerythrocytic parasite growth because a significant amount of [3H]hypoxanthine was incorporated into the parasitized red blood cells (PRBC) in proportion to the number of PRBC. The incorporation of [3H]hypoxanthine was almost completed in an early phase of incubation. Bovine peripheral blood leukocytes incubated with lysate of PRBC did not incorporate [3H]hypoxanthine, indicating that contaminating leukocytes were not involved in the incorporation in the PRBC culture. The incorporation of [3H]hypoxanthine was decreased markedly by the addition of certain anti-parasitic drugs such as chloroquine, quinine, and pyrimethamine. This inhibition test was performed quantitatively with high sensitivity. Based on these results, this short-term culture seemed to be useful for drug screening or studying the mechanisms of theilerial infection. However, anti-T. sergenti antibodies failed to inhibit the [3H]hypoxanthine incorporation.

As of the end of September 1989, 52 EXS Dacron grafts had been implanted for femoropopliteal bypass operations. The distal ends of 27 grafts were anastomosed to above-knee popliteal arteries and those of 25 grafts to below-knee popliteal arteries. The cumulative patency rate of above-knee grafts was 71.3% at 54 months, and that of below-knee grafts was 78.8% at 48 months (n.s.). Kinking and stenosis of the arteriosclerotic proximal and/or mid popliteal artery when the knee was bent were angiographically remarkable. These changes may explain why some femoropopliteal grafts occlude with time and why the late results of above-knee grafts are not much better than those of below-knee grafts.

Reconstructive surgery was carried out in 93 patients of ASO and TAO. Factors influenced on prognosis were studied being compared with ASO and TAO. Cumulative 5-year patency was 60% in ASO and 25% in TAO. Distal patency was shown by total score given in each site of arteriogram. Patency rate was well correlated with combinated factors such as total score of arteriogram and back flow at site of surgery. Period from onset of symptom to surgery and site of operation also correlated with patency statistically, though total serum cholesterol, ischemic time at reconstructive surgery, and amount of bleeding at operation did not relate to prognosis. Causes of early failure and special problems of late failure in TAO were studied.

In order to elucidate the origin of elevated serum CA-125 values in patients with endometriosis, CA-125 content in the uterine endometrium, myometrium, leiomyoma, fallopian tube, ovary, adenomyotic tissue and endometriotic tissue, were measured by RIA. The CA-125 content in the normal endometrium was 334.7 +/- 39.1 U/mg-protein, and this was significantly (p less than 0.001) higher than that in the myometrium (66.1 +/- 8.6), cervical gland (131.7 +/- 24.2), fallopian tube (111.6 +/- 15.8) and ovary (64.6 +/- 15.6). Endometriotic tissue contained 217.5 +/- 23.1, and adenomyotic tissue contained 235.3 +/- 47.7. No significant difference was found between tissue from cervical and corporal malignancies of the uterus, but ovarian cancer tissue contained a high CA-125 level compared to normal ovarian tissue. The mean concentration of CA-125 in menstrual blood was 377.9 +/- 79.9 U/ml and was about 11 times as high as that seen in peripheral blood in the same donor. The fact that the endometrium contained the highest amount of CA-125 among normal tissues examined supports the hypothesis that externally developed endometrium is the primary source of elevated serum CA-125 in patients with endometriosis.

Radioprotective effects of pre‐ and post‐irradiation treatments giving zinc manganese, or one of biological response modifiers (BRMs), or subjecting mice to stressful conditions on the whole bodily irradiated mice were investigated with respect to MT induction.The normal level of MT in murine liver is as low a 1–2 nano mole/g tissue, but the level can be elevated to several or even twenty times after the administration of a heavy metal or a certain BRM or both. A stress, e.g. dermal excision also induced hepatic MT synthesis.These pretreatments to induce hepatic MT gave a strong tolerance against lethal damage to mice. The effect of combined use of BRM with manganese or zinc was more prominent. Since manganese has less adverse effects and easily eliminated from organs, the spot administration of even after the irradiation was considerably effective. Mice administered manganese manifested a quicker regaining in the number of leucocytes and erythrocyted than control mice.These investigations suggested us a ...

Out of 216 patients with Buerger's disease, 14 showed the involvement of the iliac artery in addition to the occlusive lesion in the leg arteries. It occurred within 2 to 8 years after the onset of symptom. The obliterative lesion of the iliac artery might owe its cause to a direct proximal progression of thromboangitis obliterans of the femoral artery or to a skip progression of the disease. The skip lesion of the iliac artery might be due to an ascending progress of the thromboangiitic lesion in the branch arteries of the iliac artery. The indication for arterial reconstruction in the case with the involvement of the iliac artery depends on run-off in the deep femoral artery. Out of the 14 cases, 2 underwent thromboendarterectomy with autogenous vein patch grafting of the external iliac artery and 6 underwent bypass grafting, but their long-term follow-up result was poor.

Murine antibody against Mycoplasma pulmonis (Mp) was detected sensitively and specifically in experimentally and naturally infected animals by an enzyme-linked immunosorbent assay (ELISA), using urease conjugated antimurine immunoglobulin. More than 98% of the experimentally infected mice and rats exhibited positive reaction in the ELISA two or more weeks after infection, and the titer remained for a prolonged period (up to one year) after infection. However, we failed to detect antibody in the sera of one-week-postinfected animals. Mice and rats from breeding colonies were tested with the ELISA and compared with isolation of Mp from the respiratory organs. Positive reactions were shown in the ELISA using the sera from 91% of the mice and 98% of the rats from which the organisms were isolated. Conversely, 97% of the mice and 78% of the rats among Mp-free animals showed negative results in the ELISA. The sensitivity and specificity of the complement fixation test, which has been used widely for serodiagnosis of Mp-infection, were apparently lower compared to those of the ELISA. From these results, the ELISA was found to be available for the serodiagnosis of Mp-infection in mice and rats.