Negative Geotactic Behavior of Paramecium Caudatum is Completely Described by the Mechanism of Buoyancy-Oriented Upward Swimming

This paper presents evidence that the negative geotactic behavior of Paramecium caudatum takes place by the mechanism of buoyancy-oriented upward swimming. Photographs of swimming pathways of the organisms were completely described by two dynamic equations for the translational motion of the center of gravity of the organism's body and for the rotational motion of the organism's body about its center of gravity, where the rotational torque is induced by a slight difference in position between the center of gravity and the center of buoyancy. It now seems unlikely that complicated mechanisms such as the statocyst mechanism and the gravity-propulsion mechanism, which have been proposed by many investigators, need be considered for other protozoa since preliminary observation and analysis of other ciliates such as Paramecium multimicronucleatum, Paramecium tetraurelia, and Tetrahymena pyriformis also strongly suggested that their negative geotaxis is due to buoyancy-oriented upward swimming.

Bidirectional cavopulmonary shunt with additional pulmonary blood flow

There are some controversies regarding the usefulness of leaving additional pulmonary blood flow when establishing a bidirectional cavopulmonary shunt. From April 2002 to September 2008, 13 patients (mean age, 24 +/- 16 months) underwent a bidirectional cavopulmonary shunt procedure with fine adjustment of additional pulmonary blood flow, as an intermediate step before the Fontan operation. There were no hospital deaths. Modified Blalock-Taussig shunts were left during the bidirectional cavopulmonary shunt operation in 7 patients, and pulmonary bands were tightened in 4. The main pulmonary artery with a previous pulmonary band was left open in one case. Oxygen saturation increased from 74.5% +/- 7.4% to 84.6% +/- 1.9% after the operation, cardiothoracic ratio decreased from 55.9% +/- 6.1% to 53.2% +/- 3.4%, Left ventricular end-diastolic pressure decreased from 11.0 +/- 2.6 to 7.8 +/- 3.0 mm Hg, and mean pulmonary arterial pressure from 14.7 +/- 7.5 to 10.2 +/- 3.1 mm Hg. Pulmonary artery index did not change significantly. In our experience, additional pulmonary blood flow with adjustment in each patient at the time of shunt construction was an excellent temporary palliation prior to the Fontan operation.

Air-stable Curved π-Radical Based on Corannulene: Dynamic Electronic-spin Structure Induced by Temperature-dependent Conformational Changes

A new corannulene-based curved neutral π-radical bearing a tert-butylnitroxide moiety has been synthesized and isolated as an air-stable solid. Direct attachment of the spin centre to the corannulene skeleton gives rise to an extensive spin-delocalization onto the curved π-conjugated system from the nitroxide moiety. This salient electronic feature in the curved neutral radical system and its high stability have allowed us to find a dynamic electronic-spin behaviour induced by the temperature-dependent conformational change of the nitroxide moiety, as studied by liquid-phase variable-temperature electron spin resonance and 1H electron-nuclear double resonance and electron-nuclear-nuclear triple resonance spectroscopies with the help of density functional theory calculations.

Source of N-nitrosodimethylamine in river waters of the upper Tone River basin in Japan

The presence of N-nitrosodimethylamine (NDMA) in the Hirose River and its tributaries, located in the upper Tone River basin, in the Kanto region of Japan, was investigated. NDMA was detected at high levels in the Arato River, one of the tributaries of the Hirose River, at high concentrations (up to 2,100 ng/L). Due to the confluence of the Arato River, NDMA concentration in the Hirose River increased (up to 61 ng/L). The NDMA in the Arato River was due to industrial discharge from a livestock processing plant located near the river. There were three discharges at the plant, with NDMA concentrations of 78, 11, and 33,000 ng/L. The industrial discharges from the livestock processing plant did not contain significant amounts of NDMA precursors on chloramination. On the other hand, sewage effluent was shown to contain NDMA precursors. The amounts of NDMA precursors in the sewage effluent that were rapidly transformed into NDMA were considered to be lower than those slowly transformed into NDMA.

Hydrodynamics of aortic cannulae during extracorporeal circulation in a mock aortic arch aneurysm model

This study was designed to analyze flow pattern, velocity, and strain on the aortic wall of a glass aortic arch aneurysm model during the extracorporeal circulation, and to elucidate the characteristics of flow pattern in three different aortic cannulae. Different patterns of large vortices and helical flow were made by each cannula. With the curved end-hole cannula, the high velocity flow (approximately 0.6-0.8 m/s) was blowing to the aneurismal wall without attenuating the strain rate tensor (approximately 0.2-0.25/s). With the dispersion cannula and the Soft-Flow cannula, cannular jet was attenuated in the ascending aorta creating a large vortex at a velocity less than 0.5 m/s, and the strain rate tensor on the aneurismal wall was small (less than 0.15/s). In conclusion, end-hole cannula should not be used in the operation of aortic arch aneurysm. Dispersion-type aortic cannulae were less invasive on the aortic arch aneurismal wall, but particular attention to alternative cannulation sites should be paid in cases with severe atherosclerosis on the ascending aortic wall.

[Surgical treatment of aortic root disease]

We reviewed aortic root disease and operative procedures. Between January 1982 and December 2008, aortic root operation was performed for 58 patients with various aortic root disease. We chose Bentall type operations in extensive root destructive cases and urgent or reoperative cases. Overall in-hospital mortality was 8.6% (5/58). Four patients (7.5% of survivors) died during the period of followup. Actuarial survival at 15 years was 92%. Freedom from cardiovascular event at 10 and 15 years was 81% and 27%, respectively. Of 5 reoperations in 5 patients, only 1 was required due to complications of the initial Bentall type operation. The Bentall type operations resulted in a durable result. Although, in Marfan syndrome, freedom from cardiovascular event was lower than that in non-Marfan syndrome, actuarial survival rate was equal with non-Marfan syndrome. Close observation is necessary for detecting cardiovascular event, especially in Marfan syndrome.

[Improved cardiac function after inhalation of nitric oxide and tricuspid annuloplasty in dilated cardiomyopathy patient on left ventricular assist system]

A 17-year-old man with severe cardiac failure due to dilated cardiomyopathy was treated by medication. As he did not improve, he had indication for transplantation of the heart and was put on a ventricular assist system as a bridge until he could be transplanted. He also had severe tricuspid regurgitation and tricuspid annuloplasty was performed. Inhalation of nitric oxide was used to decrease pulmonary vascular resistance. Although cerebral infarction was present postoperatively, he is waiting for transplant without paralysis. The ventricular assist system proved to be useful therapy for serious cardiac failure due to terminal dilated cardiomyopathy.

Structural analyses of chromosomes and their constituent proteins

The importance of chromosome structural study is first described. Then an overview of historical imaging methods that enable us to quantitatively understand chromosome images and structure is given with special reference to the identification of small plant chromosomes and development of their quantitative chromosome maps. A three-dimensional understanding of chromosome distribution within a nucleus answers why the gene-rich regions localize at both ends of chromosomes, especially in the case of species with Rabl orientation. Not only imaging methods but also proteomic approaches are effective in understanding chromosome structure. Over 200 proteins have been identified by proteome analysis of human metaphase chromosomes, and are categorized into four distinct groups according to their nature and localization on chromosomes. These are chromosome coating proteins (CCPs), chromosome peripheral proteins (CPPs), chromosome structural proteins (CSPs), and chromosome fibrous proteins (CFPs). A chromosome four layer model has been developed accordingly. Case studies on individual identified proteins are further described, and the functional similarities of CPPs are exemplified. In addition the controversial roles of CSPs (topoisomerase and condensin), especially for development of higher-order chromosome structure, are discussed. Finally, it is concluded that further advances in chromosome research are necessary to solve an enigma lasting nearly two centuries, that is, why chromosomes retain the same shape in plants and animals.

Olmesartan improves left ventricular function in pressure-overload hypertrophied rat heart by blocking angiotensin II receptor with synergic effects of upregulation of angiotensin converting enzyme 2

It is not clear how the blocking effect of angiotensin II receptors by olmesartan affects the functional recovery of pressure-overload hypertrophied heart. Hypertrophied heart was created by abdominal aortic banding above the celiac artery in Wistar rats at the age of eight weeks. Hypertrophied heart was excised and studied at 10 and 16 weeks after the operation (HT groups). For the last four weeks before the experiment, olmesartan (0.2 mg/kg per day) was administered subcutaneously by osmotic minipumps (Olm groups). Left ventricular function was measured by Langendorff perfusion. The levels of mRNA for angiotensin-converting enzyme (ACE), ACE2 and extracellular signal-regulated kinases (ERKs) in myocardium were analyzed by RT-PCR. Left ventricular systolic (+d P/dtmax, left ventricular systolic pressure) and diastolic functions (-d P/dtmax, tau) were impaired in HT groups, while in Olm groups they were significantly improved. The left ventricle to body weight (LV/BW) ratio increased significantly in HT groups, but in Olm groups the LV/BW ratio decreased significantly in comparison with HT groups. The ACE2 mRNA level was significantly higher in Olm groups as compared with HT groups. Plasma angiotensin II and the ERK mRNA level in HT groups increased significantly, but decreased in Olm groups in comparison with HT groups significantly. Olmesartan improved left ventricular function and hypertrophy through the increase of the ACE2 mRNA and decrease of both angiotensin II and ERK mRNA in pressure-overload rat heart.

Effect of Supplemental Oxygen versus Dobutamine Administration on Liver Oxygen Tension in dPP-Guided Normovolemic Pigs

<i>Background:</i> Difference in pulse pressure (dPP) confirms adequate intravascular filling as a prerequisite for tissue perfusion. We hypothesized that both oxygen and dobutamine increase liver tissue oxygen tension (pt<i>O</i>₂). <i>Methods:</i> Eight anesthetized pigs received dPP-guided fluid management. Hepatic p<i>O</i>₂ was measured with Clark-type electrodes placed subcapsularly, and on the liver surface. Pigs received: (1) supplemental oxygen (F_i<i>O</i>₂ 1.0); (2) dobutamine 2.5 μg/kg/min, and (3) dobutamine 5 μg/kg/min. Data were analyzed using repeated-measures ANOVA followed by a Tukey post-test for multiple comparisons. pt<i>O</i>₂measured subcapsularly and at the liver surface were compared using the Bland-Altman plot. <i>Results:</i> Variation in F_i<i>O</i>₂ changed local hepatic tissue pt<i>O</i>₂ [subcapsular measurement: 39 ± 12 (F_i<i>O</i>₂ 0.3), 89 ± 35 mm Hg (F_i<i>O</i>₂ 1.0, p = 0.01 vs. F_i<i>O</i>₂ 0.3), 44 ± 10 mm Hg (F_i<i>O</i>₂ 0.3, p = 0.05 vs. F_iO₂ 1.0); surface measurement: 52 ± 35 (F_i<i>O</i>₂ 0.3), 112 ± 24 mm Hg (F_i<i>O</i>₂ 1.0, p = 0.001 vs. F_i<i>O</i>₂ 0.3), 54 ± 24 mm Hg (F_i<i>O</i>₂ 0.3, p = 0.001 vs. F_i<i>O</i>₂ 1.0)]. Surface measurements were widely scattered compared to subcapsular measurements (bias: –15 mm Hg, precision: 76.3 mm Hg). Dobutamine did not affect hepatic oxygenation. <i>Conclusion:</i> Supplemental oxygen increased hepatic tissue p<i>O</i>₂ while dobutamine did not. Although less invasive, the use of surface measurements is discouraged.

[Interrupted aortic arch type B survived after single stage repair and continuous hemodiafiltration; report of a case]

A 14-day-old, 2,042 g neonate with interrupted aortic arch (IAA) type B was admitted to our hospital because of respiratory failure. Although alprostadil and alprostadil alfadex were used to keep the ductus arteriosus open, her congestive heart failure became worse and anuria and metabolic acidosis started to appear. We performed single-stage repair for her at 14 days old. Continuous hemodiafiltration (CHDF) was initiated immediately after the operation and peritoneal dialysis was started after paralytic ileus improved. CHDF improved her renal function and she was discharged at postoperative day 84. We conclude that CHDF is effective for neonates with acute renal failure although circulation management is rather difficult.

Dynamic cardiomyoplasty using artificial muscle

Dynamic cardiomyoplasty using latissimus dorsi muscle was previously used to compensate for congestive heart failure. Now, however, this method is not acceptable because the long-term result was not as expected owing to fatigue of the skeletal muscle. BioMetal fiber developed by Toki Corporation is one of the artificial muscles activated by electric current. The behavior of this fiber is similar to that of organic muscle. We made an artificial muscle like the latissimus dorsi using BioMetal fiber and tested whether we could use this new muscle as a cardiac supporting device. Testing one Biometal fiber showed the following performance: practical use maximal generative force was 30 g, exercise variation was 50%, and the standard driving current was 220 mA. We created a 4 x 12-cm tabular artificial muscle using 8 BioMetal fibers as a cardiac support device. We also made a simulation circuit composed of a 6 x 8-cm soft bag with unidirectional valves, reservoir, and connecting tube. The simulation circuit was filled with water and the soft bag was wrapped with the artificial muscle device. After powering the device electrically at 9 V with a current of 220 mA for each fiber, we measured the inside pressure and observed the movement of the artificial device. The artificial muscle contracted in 0.5 s for peak time and squeezed the soft bag. The peak pressure inside the soft bag was measured as 10 mmHg. Although further work will be needed to enhance the speed of deformability and movement simulating contraction, we conclude that artificial muscle may be potentially useful as a cardiac assistance device that can be developed for dynamic cardiomyoplasty.

Description of International Caenorhabditis elegans Experiment first flight (ICE-FIRST)

Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads.