Clinical efficacy of intermittent pressure augmented–retrograde cerebral perfusion

ObjectiveDuring aortic surgery under hypothermic circulatory arrest, retrograde cerebral perfusion (RCP) is commonly used as a cerebroprotective method to extend the duration of circulatory arrest safely. Kitahori and colleagues described a novel protocol of RCP using intermittent pressure augmented (IPA)–RCP in 2005. The aim of the present study was to determine the clinical effectiveness of this novel protocol.MethodsA total of 20 consecutive patients undergoing total replacement of the aortic arch were assigned to a conventional RCP (n = 10) or an IPA-RCP group (n = 10). Cerebral perfusion was provided at a continuous venous pressure of 25 mm Hg in the conventional RCP, and venous pressure was intermittently provided at 20 mm Hg for 120 seconds and at 45 mm Hg for 30 seconds in the IPA-RCP group. The clinical outcomes were compared between the 2 groups. Regional cerebral oxygen saturation (rSO2) was measured using near infrared spectroscopy every 10 minutes from the beginning of RCP initiation. To represent the brain oxygen consumption, the decline ratio of rSO2 was calculated.ResultsThere was no surgical mortality or major neurologic complications in either group. The interval from the end of surgery to full wakefulness was significantly shorter in the IPA-RCP group (85 ± 64 minutes) than in the conventional RCP group (310 ± 282 minutes; P < .05). Although the initial rSO2 value did not show significant difference in both groups, the rSO2 with IPA-RCP was greater than that with conventional RCP from 10 to 70 minutes (P < .05). The decline ratio of rSO2 was lower in the IPA-RCP group than in the RCP perfusion group at all points (P < .05).ConclusionsIPA-RCP might provide more homogenous cerebral perfusion and a more effective oxygen supply to the brain with better clinical results than conventional RCP

Human Hematopoietic Stem Cells Can Survive In Vitro for Several Months

We previously reported that long-lasting in vitro hematopoiesis could be achieved using the cells differentiated from primate embryonic stem (ES) cells. Thus, we speculated that hematopoietic stem cells differentiated from ES cells could sustain long-lasting in vitro hematopoiesis. To test this hypothesis, we investigated whether human hematopoietic stem cells could similarly sustain long-lasting in vitro hematopoiesis in the same culture system. Although the results varied between experiments, presumably due to differences in the quality of each hematopoietic stem cell sample, long-lasting in vitro hematopoiesis was observed to last up to nine months. Furthermore, an in vivo analysis in which cultured cells were transplanted into immunodeficient mice indicated that even after several months of culture, hematopoietic stem cells were still present in the cultured cells. To the best of our knowledge, this is the first report to show that human hematopoietic stem cells can survive in vitro for several months

Total aortic arch replacement under intermittent pressure-augmented retrograde cerebral perfusion

Kitahori, Kawata, Takamoto et al. described the effectiveness of a novel protocol for retrograde cerebral perfusion that included intermittent pressure augmentation for brain protection in a canine model. Based on their report, we applied this novel technique clinically. Although the duration of circulatory arrest with retrograde cerebral perfusion was long, the patient recovered consciousness soon after the operation and had no neurological deficit. Near-infrared oximetry showed recovery of intracranial blood oxygen saturation every time the pressure was augmented

Establishment of Mouse Embryonic Stem Cell-Derived Erythroid Progenitor Cell Lines Able to Produce Functional Red Blood Cells

BACKGROUND: The supply of transfusable red blood cells (RBCs) is not sufficient in many countries. If erythroid cell lines able to produce transfusable RBCs in vitro were established, they would be valuable resources. However, such cell lines have not been established. To evaluate the feasibility of establishing useful erythroid cell lines, we attempted to establish such cell lines from mouse embryonic stem (ES) cells. METHODOLOGY/PRINCIPAL FINDINGS: We developed a robust method to obtain differentiated cell lines following the induction of hematopoietic differentiation of mouse ES cells and established five independent hematopoietic cell lines using the method. Three of these lines exhibited characteristics of erythroid cells. Although their precise characteristics varied, each of these lines could differentiate in vitro into more mature erythroid cells, including enucleated RBCs. Following transplantation of these erythroid cells into mice suffering from acute anemia, the cells proliferated transiently, subsequently differentiated into functional RBCs, and significantly ameliorated the acute anemia. In addition, we did not observe formation of any tumors following transplantation of these cells. CONCLUSION/SIGNIFICANCE: To the best of our knowledge, this is the first report to show the feasibility of establishing erythroid cell lines able to produce mature RBCs. Considering the number of human ES cell lines that have been established so far, the intensive testing of a number of these lines for erythroid potential may allow the establishment of human erythroid cell lines similar to the mouse erythroid cell lines described here. In addition, our results strongly suggest the possibility of establishing useful cell lines committed to specific lineages other than hematopoietic progenitors from human ES cells

Reference values for the locomotive syndrome risk test quantifying mobility of 8681 adults aged 20–89 years: A cross-sectional nationwide study in Japan

Background The locomotive syndrome risk test was developed to quantify the decrease in mobility among adults, which could eventually lead to disability. The purpose of this study was to establish reference values for the locomotive syndrome risk test for adults and investigate the influence of age and sex. Methods We analyzed 8681 independent community dwellers (3607 men, 5074 women). Data pertaining to locomotive syndrome risk test (the two-step test, the stand-up test, and the 25-question geriatric locomotive function scale [GLFS-25]) scores were collected from seven administrative areas of Japan. Results The reference values of the three test scores were generated and all three test scores gradually decreased among young-to-middle-aged individuals and rapidly decreased in individuals aged over 60 years. The stand-up test score began decreasing significantly from the age of 30 years. The trajectories of decrease in the two-step test score with age was slightly different between men and women especially among the middle-aged individuals. The two physical test scores were more sensitive to aging than the self-reported test score. Conclusion The reference values generated in this study could be employed to determine whether an individual has mobility comparable to independent community dwellers of the same age and sex

Real-time 3D Photoacoustic Visualization System with a Wide Field of View for Imaging Human Limbs [version 2; referees: 2 approved]

Background: A breast-specific photoacoustic imaging (PAI) system prototype equipped with a hemispherical detector array (HDA) has been reported as a promising system configuration for providing high morphological reproducibility for vascular structures in living bodies. Methods: To image the vasculature of human limbs, a newly designed PAI system prototype (PAI-05) with an HDA with a higher density sensor arrangement was developed. The basic device configuration mimicked that of a previously reported breast-specific PAI system. A new imaging table and a holding tray for imaging a subject's limb were adopted. Results: The device’s performance was verified using a phantom. Contrast of 8.5 was obtained at a depth of 2 cm, and the viewing angle reached up to 70 degrees, showing sufficient performance for limb imaging. An arbitrary wavelength was set, and a reasonable PA signal intensity dependent on the wavelength was obtained. To prove the concept of imaging human limbs, various parts of the subject were scanned. High-quality still images of a living human with a wider size than that previously reported were obtained by scanning within the horizontal plane and averaging the images. The maximum field of view (FOV) was 270 mm × 180 mm. Even in movie mode, one-shot 3D volumetric data were obtained in an FOV range of 20 mm in diameter, which is larger than values in previous reports. By continuously acquiring these images, we were able to produce motion pictures. Conclusion: We developed a PAI prototype system equipped with an HDA suitable for imaging limbs. As a result, the subject could be scanned over a wide range while in a more comfortable position, and high-quality still images and motion pictures could be obtained