Organ Boundary Circuits Regulate Sox9+ Alveolar Tuft Cells During Post-Pneumonectomy Lung Regeneration

Tissue homeostasis is controlled by cellular circuits governing cell growth, organization, and differentation. In this study we identify previously undescribed cell-to-cell communication that mediates information flow from mechanosensitive pleural mesothelial cells to alveolar-resident stem-like tuft cells in the lung. We find mesothelial cells to express a combination of mechanotransduction genes and lineage-restricted ligands which makes them uniquely capable of responding to tissue tension and producing paracrine cues acting on parenchymal populations. In parallel, we describe a large population of stem-like alveolar tuft cells that express the endodermal stem cell markers Sox9 and Lgr5 and a receptor profile making them uniquely sensitive to cues produced by pleural Mesothelium. We hypothesized that crosstalk from mesothelial cells to alveolar tuft cells might be central to the regulation of post-penumonectomy lung regeneration. Following pneumonectomy, we find that mesothelial cells display radically altered phenotype and ligand expression, in a pattern that closely tracks with parenchymal epithelial proliferation and alveolar tissue growth. During an initial pro-inflammatory stage of tissue regeneration, Mesothelium promotes epithelial proliferation via WNT ligand secretion, orchestrates an increase in microvascular permeability, and encourages immune extravasation via chemokine secretion. This stage is followed first by a tissue remodeling period, characterized by angiogenesis and BMP pathway sensitization, and then a stable return to homeostasis. Coupled with key changes in parenchymal structure and matrix production, the cumulative effect is a now larger organ including newly-grown, fully-functional tissue parenchyma. This study paints Mesothelial cells as a key orchestrating cell type that defines the boundary of the lung and exerts critical influence over the tissue-level signaling state regulating resident stem cell populations. The cellular circuits unearthed here suggest that human lung regeneration might be inducible through well-engineered approaches targeting the induction of tissue regeneration and safe return to homeostasis.

Semisolid Enteral Nutrients Alter the Pharmacokinetics of Orally Administered Levetiracetam in Rats

Enteral nutrients (ENs) affect the plasma drug concentration of orally co-administered drugs, particularly those of antiepileptic drugs, such as phenytoin and carbamazepine. However, few studies have reported the interactions of levetiracetam (LEV), an upcoming antiepileptic drug, with ENs. In this study we aimed to investigate the pharmacokinetics of LEV in 55 rats after oral co-administration of LEV with liquid or semisolid ENs. Compared with the control group, co-administration with Terumeal ® Soft significantly decreased the plasma LEV concentration at 0.5, 1, and 2 h and area under the plasma concentration-time curve from 0 to 3 h (AUC0→3h) (P < 0.01). However, the AUC0→3h of LEV remained unchanged following the administration of Terumeal ® Soft 2 h after the initial LEV administration. Moreover, co-administration with semisolid Racol® NF delayed the absorption of LEV without decreasing the AUC0→3h, whereas liquid Racol ® NF did not alter LEV pharmacokinetics. Thus, co-administration of LEV with Terumeal® Soft reduced the absorption of LEV from the gastrointestinal tract, which was prevented by administering Terumeal ® Soft 2 h after LEV administration. Semisolid Racol ® NF altered LEV pharmacokinetics without decreasing its gastrointestinal absorption. Our findings suggested that careful monitoring of the plasma LEV levels is necessary when co-administering LEV with Terumeal ® Soft, semisolid Racol ® NF, or any other semisolid ENs, to prevent the inadvertent effects of the interaction between LEV and ENs.

A novel ex vivo lung cancer model based on bioengineered rat lungs

Introduction: Two-dimensional cell cultures have contributed substantially to lung cancer research, but 3D cultures are gaining attention as a new, more efficient, and effective research model. A model reproducing the 3D characteristics and tumor microenvironment of the lungs in vivo, including the co-existence of healthy alveolar cells with lung cancer cells, is ideal. Here, we describe the creation of a successful ex vivo lung cancer model based on bioengineered lungs formed by decellularization and recellularization. Methods: Human cancer cells were directly implanted into a bioengineered rat lung, which was created with a decellularized rat lung scaffold reseeded with epithelial cells, endothelial cells and adipose-derived stem cells. Four human lung cancer cell lines (A549, PC-9, H1299, and PC-6) were applied to demonstrate forming cancer nodules on recellularized lungs and histopathological assessment were made among these models. MUC-1 expression analysis, RNA-seq analysis and drug response test were performed to demonstrate the superiority of this cancer model. Results: The morphology and MUC-1 expression of the model were like those of lung cancer in vivo. RNA sequencing revealed an elevated expression of genes related to epithelial-mesenchymal transition, hypoxia, and TNF-α signaling via NF-κB; but suppression of cell cycle-related genes including E2F. Drug response assays showed that gefitinib suppressed PC-9 cell proliferation equally well in the 3D lung cancer model as in 2D culture dishes, albeit over a smaller volume of cells, suggesting that fluctuations in gefitinib resistance genes such as JUN may affect drug sensitivity. Conclusions: A novel ex vivo lung cancer model was closely reproduced the 3D structure and microenvironment of the actual lungs, highlighting its possible use as a platform for lung cancer research and pathophysiological studies.

Spontaneous pleural aspergillosis in an immunocompetent young adult treated with minimally invasive surgery

Spontaneous cases of pleural aspergillosis in healthy adults are rare, and the optimal therapeutic approach has not been established. Here we report a rare case of spontaneous pleural aspergillosis in an otherwise healthy young adult. Two-stage surgery with decortication and cavernostomy, followed by systemic antifungal therapy, finally resulted in a successful resolution of his empyema without any serious complications. In young patients with good pulmonary compliance, less invasive procedures, such as thoracoscopic decortication and/or carvernotomy, is a potential treatment option.

A Pulmonary Vascular Model From Endothelialized Whole Organ Scaffolds

The development of an in vitro system for the study of lung vascular disease is critical to understanding human pathologies. Conventional culture systems fail to fully recapitulate native microenvironmental conditions and are typically limited in their ability to represent human pathophysiology for the study of disease and drug mechanisms. Whole organ decellularization provides a means to developing a construct that recapitulates structural, mechanical, and biological features of a complete vascular structure. Here, we developed a culture protocol to improve endothelial cell coverage in whole lung scaffolds and used single-cell RNA-sequencing analysis to explore the impact of decellularized whole lung scaffolds on endothelial phenotypes and functions in a biomimetic bioreactor system. Intriguingly, we found that the phenotype and functional signals of primary pulmonary microvascular revert back—at least partially—toward native lung endothelium. Additionally, human induced pluripotent stem cell-derived endothelium cultured in decellularized lung systems start to gain various native human endothelial phenotypes. Vascular barrier function was partially restored, while small capillaries remained patent in endothelial cell-repopulated lungs. To evaluate the ability of the engineered endothelium to modulate permeability in response to exogenous stimuli, lipopolysaccharide (LPS) was introduced into repopulated lungs to simulate acute lung injury. After LPS treatment, proinflammatory signals were significantly increased and the vascular barrier was impaired. Taken together, these results demonstrate a novel platform that recapitulates some pulmonary microvascular functions and phenotypes at a whole organ level. This development may help pave the way for using the whole organ engineering approach to model vascular diseases.

Lung Microvascular Niche, Repair, and Engineering

Biomaterials have been used for a long time in the field of medicine. Since the success of "tissue engineering" pioneered by Langer and Vacanti in 1993, tissue engineering studies have advanced from simple tissue generation to whole organ generation with three-dimensional reconstruction. Decellularized scaffolds have been widely used in the field of reconstructive surgery because the tissues used to generate decellularized scaffolds can be easily harvested from animals or humans. When a patient's own cells can be seeded onto decellularized biomaterials, theoretically this will create immunocompatible organs generated from allo- or xeno-organs. The most important aspect of lung tissue engineering is that the delicate three-dimensional structure of the organ is maintained during the tissue engineering process. Therefore, organ decellularization has special advantages for lung tissue engineering where it is essential to maintain the extremely thin basement membrane in the alveoli. Since 2010, there have been many methodological developments in the decellularization and recellularization of lung scaffolds, which includes improvements in the decellularization protocols and the selection and preparation of seeding cells. However, early transplanted engineered lungs terminated in organ failure in a short period. Immature vasculature reconstruction is considered to be the main cause of engineered organ failure. Immature vasculature causes thrombus formation in the engineered lung. Successful reconstruction of a mature vasculature network would be a major breakthrough in achieving success in lung engineering. In order to regenerate the mature vasculature network, we need to remodel the vascular niche, especially the microvasculature, in the organ scaffold. This review highlights the reconstruction of the vascular niche in a decellularized lung scaffold. Because the vascular niche consists of endothelial cells (ECs), pericytes, extracellular matrix (ECM), and the epithelial-endothelial interface, all of which might affect the vascular tight junction (TJ), we discuss ECM composition and reconstruction, the contribution of ECs and perivascular cells, the air-blood barrier (ABB) function, and the effects of physiological factors during the lung microvasculature repair and engineering process. The goal of the present review is to confirm the possibility of success in lung microvascular engineering in whole organ engineering and explore the future direction of the current methodology.

Successful resection to treat idiopathic azygos vein aneurysm

Azygos vein aneurysm is a rare disease. Surgical resection is usually performed when it ruptures. To avoid the thromboembolism, procedures that do not touch or push the aneurysm are recommended. Herein, we report a case of idiopathic azygos vein aneurysm. A 56-year-old woman was admitted to the hospital for right lateral chest pain. Chest enhanced multi-detector CT revealed an azygos vein aneurysm in the posterior mediastinal space. No thrombus in the aneurysm was detected before surgery. Video-assisted thoracic surgery was performed to treat the aneurysm. The patient was discharged from the hospital 4 days after surgery. Video-assisted thoracic surgery was a good option to treat an azygos vein aneurysm, and an enhanced multi-detector CT was useful for performing surgery safely.

Functional Expression and Characterization of Tetrachloroethene Dehalogenase From Geobacter sp

Reductive dehalogenase (RDase) consists of two parts, RdhA and RdhB. RdhA is the catalytic subunit, harboring a cobalamin cofactor and two Fe-S clusters. RdhA is anchored to the cytoplasmic membrane via the membrane anchoring subunit, RdhB. There are many genes encoding RDases in the genome of organohalide-respiring bacteria, including Dehalococcoides spp. However, most genes have not been functionally characterized. Biochemical studies on RDases have been hampered by difficulties encountered in their expression and purification. In this study, we have expressed, purified and characterized RdhA of RDase for tetrachloroethene (PceA) from Geobacter sp. PceA was expressed as a fusion protein with a trigger factor tag in Escherichia coli. PceA was purified and denatured in aerobic condition. Subsequently, this protein was refolded in the presence of FeCl₃, Na₂S and cobalamin in anaerobic condition. The reconstituted PceA exhibited dechlorination ability for tetrachloroethene. UV-Vis spectroscopy has shown that it contains cobalamin and Fe-S clusters. Since this method requires anaerobic manipulation only in the reconstituting process and has a relatively high yield, it will enable further biochemical studies of RDases.

Balloon-Based Organ Retractor With Increased Safety and Reduced Invasiveness During Video-Assisted Thoracoscopic Surgery

OBJECTIVES

In recent years, video-assisted thoracoscopic surgery (VATS) has increasingly become the preferred technique for thoracic surgery. However, the inherent characteristics of the lungs as large, soft, slippery, and delicate creates difficulties for pulmonary surgery. In this article, we outline the development and assessment of a balloon-based organ retractor for VATS via collaboration between medical and engineering personnel.

METHODS

A dry lab trial and accompanying questionnaire assessment were performed by a group of thoracic surgeons. Objective pressure measurements were obtained, and animal experiment on pigs was performed.

RESULTS

In the dry lab trial, use of the developed organ retractor required significantly less time and resulted in fewer difficulties than using a Cherry Dissector. The measured pressure per mm² of the developed retractor was clearly lower than that for the Cherry Dissector. The questionnaire completed by the surgeons following the dry lab and animal experiments showed that most of the surgeons (7 surgeons out of 9) were satisfied with the quality of the balloon-based retractor based on a score of 3.13 ± 0.28 (mean ± standard deviation) out of 4.0. During the animal experiment, the balloon-based retractor provided stable and clear viewing with minimal need for adjustment.

CONCLUSION

This balloon-based retractor could contribute to increased safety and less-invasive VATS.

Sodium hydroxide based non-detergent decellularizing solution for rat lung

Lung transplantation is the last option for the treatment of end stage chronic lung disorders. Because the shortage of donor lung organs represents the main hurdle, lung regeneration has been considered to overcome this hurdle. Recellularization of decellularized organ scaffold is a promising option for organ regeneration. Although detergents are ordinarily used for decellularization, other approaches are possible. Here we used high alkaline (pH12) sodium hydroxide (NaOH)-PBS solution without detergents for lung decellularization and compared the efficacy on DNA elimination and ECM preservation with detergent based decellularization solutions CHAPS and SDS. Immunohistochemical image analysis showed that cell components were removed by NaOH solution as well as other detergents. A Collagen and GAG assay showed that the collagen reduction of the NaOH group was comparable to that of the CHAPS and SDS groups. However, DNA reduction was more significant in the NaOH group than in other groups (p < 0.0001). The recellularization of HUVEC revealed cell attachment was not inferior to that of the SDS group. Ex vivo functional analysis showed 100% oxygen ventilation increased oxygen partial pressure as artificial hemoglobin vesicle-PBS solution passed through regenerated lungs in the SDS or NaOH group. It was concluded that the NaOH-PBS based decellularization solution was comparable to ordinal decellularizaton solutions and competitive in cost effectiveness and residues in the decellularized scaffold negligible, thus providing another potential option to detergent for future clinical usage.

Successful Resection of locally infiltrative Glomus Tumor without pulmonary resection

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Extracutaneous glomus tumors occurring in the bronchus is very rare.

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Two term resections enabled us to make an accurate diagnosis and evaluation.

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After bronchoscopic treatment, curative pulmonary resection was performed and preservation of lung function was successful.

Introduction

Extracutaneous glomus tumors occurring in the bronchus is very rare. Complete resection is basic procedure for treatment of glomus tumor. We present a glomus tumor of the left main bronchus that was successfully treated with rigid bronchoscopy followed by sleeve resection of the left main bronchus.

Presentation of case

A 56-year-old man underwent two term resections to glomus tumor that originated from the left main bronchus. Firstly, we performed palliative resection with rigid bronchoscopy to make the correct diagnosis and evaluate the extent of the tumor. We subsequently performed curative resection. No complications or recurrence has occurred since the operation took place one year ago.

Discussion

Before curative resection, it is important to confirm the diagnosis and spread of the tumor. Therefore, palliative tumor resection by rigid bronchoscopy was useful to make the correct diagnosis, evaluate the extent of the tumor and open the bronchial lumen. After bronchoscopic treatment, curative pulmonary resection was performed and preservation of lung function was successful.

Conclusion

Two term resections enabled us to make an accurate diagnosis and evaluation, thereby preserving respiratory function without pulmonary resection.

Transplantation of bioengineered rat lungs recellularized with endothelial and adipose-derived stromal cells

Bioengineered lungs consisting of a decellularized lung scaffold that is repopulated with a patient's own cells could provide desperately needed donor organs in the future. This approach has been tested in rats, and has been partially explored in porcine and human lungs. However, existing bioengineered lungs are fragile, in part because of their immature vascular structure. Herein, we report the application of adipose-derived stem/stromal cells (ASCs) for engineering the pulmonary vasculature in a decellularized rat lung scaffold. We found that pre-seeded ASCs differentiated into pericytes and stabilized the endothelial cell (EC) monolayer in nascent pulmonary vessels, thereby contributing to EC survival in the regenerated lungs. The ASC-mediated stabilization of the ECs clearly reduced vascular permeability and suppressed alveolar hemorrhage in an orthotopic transplant model for up to 3 h after extubation. Fibroblast growth factor 9, a mesenchyme-targeting growth factor, enhanced ASC differentiation into pericytes but overstimulated their proliferation, causing a partial obstruction of the vasculature in the regenerated lung. ASCs may therefore provide a promising cell source for vascular regeneration in bioengineered lungs, though additional work is needed to optimize the growth factor or hormone milieu for organ culture.

Ratio of C-reactive protein to albumin is a prognostic factor for operable non-small-cell lung cancer in elderly patients

PURPOSE

The aim of this retrospective study was to evaluate inflammation-based scoring as a prognostic factor for operable non-small-cell lung cancer (NSCLC) in elderly patients.

METHODS

We collected preoperative data from 108 patients aged above 80 years with NSCLC. Inflammation-based scoring systems, including the C-reactive protein to albumin ratio (CAR) and the Glasgow prognostic score (GPS), as well as other clinicopathological factors, were evaluated as potential prognostic factors.

RESULTS

The median patient age was 82 (range 80-93) years and the 5-year overall and disease-specific survival rates were 49.7 and 73.9%, respectively. The cut-off value for CAR was calculated using a receiver operator characteristics analysis and patients were dichotomized accordingly. Patients with a low CAR had significantly higher overall survival than those with a high CAR (<0.028; 65.2% vs. ≥0.028; 31.0%, respectively; p < 0.01). In univariate analysis, female gender, a low Charlson comorbidity index of 0 or 1 and a low CAR were significantly identified in overall survival. On multivariate analysis, a low CAR (p = 0.03, hazard ratio: 2.13, 95% confidence interval 1.074-4.295) was identified as a significant prognostic factor.

CONCLUSIONS

The preoperative CAR is a useful predictor of overall survival and could be a simple prognostic tool to help identify resectable NSCLC in elderly patients.

Deuterium MR in Vivo Imaging of the Rat Eye Using 2H2O

In vivo euterium MR imaging (2H MR) was investigated in rats after intraperitoneal administration of deuterated saline, and a dynamic study of the water movement in rat eyes was performed. Deuterium MR imaging was carried out by means of a gradient-echo (GRE) and a spin-echo (SE) pulse sequence. The rat eye was imaged in 2H MR more selectively by SE than by GRE, but a lower signal-to-noise ratio was obtained in 2H MR imaging using the SE sequence. The MR signal intensity of the rat eye was followed by a 3-compartment model, which enabled determination of the flow rate constant of the water in the eye (0.359/min). Deuterium MR imaging is useful to visualize the dynamic change of water in rat eyes using 2H MR at the same magnetic field (2 T) that can also be used for conventional MR imaging in humans.

Quiet T1-Weighted Pointwise Encoding Time Reduction with Radial Acquisition for Assessing Myelination in the Pediatric Brain

BACKGROUND AND PURPOSE

T1-weighted pointwise encoding time reduction with radial acquisition (PETRA) sequences require limited gradient activity and allow quiet scanning. We aimed to assess the usefulness of PETRA in pediatric brain imaging.

MATERIALS AND METHODS

We included consecutive pediatric patients who underwent both MPRAGE and PETRA. The contrast-to-noise and contrast ratios between WM and GM were compared in the cerebellar WM, internal capsule, and corpus callosum. The degree of myelination was rated by using 4-point scales at each of these locations plus the subcortical WM in the anterior frontal, anterior temporal, and posterior occipital lobes. Two radiologists made all assessments, and the intra- and interrater agreement was calculated by using intraclass correlation coefficients. Acoustic noise on MPRAGE and PETRA was measured.

RESULTS

We included 56 patients 5 days to 14 years of age (mean age, 36.6 months) who underwent both MPRAGE and PETRA. The contrast-to-noise and contrast ratios for PETRA were significantly higher than those for MPRAGE (P < .05), excluding the signal ratio for cerebellar WM. Excellent intra- and interrater agreement were obtained for myelination at all locations except the cerebellar WM. The acoustic noise on PETRA (58.2 dB[A]) was much lower than that on MPRAGE (87.4 dB[A]).

CONCLUSIONS

PETRA generally showed better objective imaging quality without a difference in subjective image-quality evaluation and produced much less acoustic noise compared with MPRAGE. We conclude that PETRA can substitute for MPRAGE in pediatric brain imaging.

Management of unexpected intraoperative bleeding during thoracoscopic pulmonary resection: a single institutional experience

PURPOSE

Unexpected intraoperative bleeding during thoracoscopic surgery, necessitating emergency conversion to thoracotomy, is gradually being reported. We reviewed our experience of encountering unexpected bleeding during thoracoscopic surgery.

METHODS

We defined "unexpected intraoperative bleeding" as the need for hemostatic procedures with angiorrhaphy, with or without a sealant. The location, cause, and management of injured vessels, and perioperative outcomes were investigated and compared with those for patients without injured vessels.

RESULTS

Between 2007 and 2014, a total of 241 thoracoscopic anatomical pulmonary resections were performed at our hospital. Twenty (8.3 %) of these patients required hemostatic procedures with angiorrhaphy, with or without a sealant. The main injured vessels were the pulmonary artery (n = 13) and vein (n = 3) and the main causes of injury were related to technical issues with energy devices and staplers. There were no morbidities related to intraoperative bleeding. The operation time and blood loss were significantly greater in the patients with vessel injury than in those without vessel injury, but perioperative morbidities and the duration of chest tube insertion (4.5 vs. 3.5 days, average, p = 0.20) and postoperative hospital stay (12.7 vs. 11.0 days, average, p = 0.08) were not significantly different.

CONCLUSIONS

The frequency of unexpected bleeding was relatively high in this series, but its management and outcomes were satisfactory in terms of safety.

Fast electrical control of single electron spins in quantum dots with vanishing influence from nuclear spins

We demonstrate fast universal electrical spin manipulation with inhomogeneous magnetic fields. With fast Rabi frequency up to 127 MHz, we leave the conventional regime of strong nuclear-spin influence and observe a spin-flip fidelity >96%, a distinct chevron Rabi pattern in the spectral-time domain, and a spin resonance linewidth limited by the Rabi frequency, not by the dephasing rate. In addition, we establish fast z rotations up to 54 MHz by directly controlling the spin phase. Our findings will significantly facilitate tomography and error correction with electron spins in quantum dots.

Mechanisms of the formation of the peritoneal dissemination in gastric cancer

To clarify the mechanisms of the formation of peritoneal dissemination, a new animal model by the i.p. inoculation of highly metastatic gastric cancer cell line MKN-45-P was developed. Peritoneal dissemination with bloody ascites was found in 100% of nude mice, injected 1x10(7) MKN-45-P cells in suspension into the peritoneal cavity. By a highly sensitive method for specific detection of metastasized human tumor cells in nude mice using polymerase chain reaction, a human beta-globin-related sequence in the DNA from various parts of the peritoneum was specifically amplified and detected by gel electrophoresis and by a specific oligonucleotide probe. Greater omentum showed a strong signal of the amplified fragments of human beta-globin gene from the 1st day and the signals gradually increased. The signals in the gonadal fat, mesentery and ovarium could be weakly detected on the Ist day, transiently decreased on the 3rd day, and then increased from the 7th day. In the diaphragm, and abdominal wall, signals could be detected from the 7th day. In contrast, small intestine and colon did not show any human beta-globin signals. In greater omentum and gonadal fat, cancer cells were selectively detected in the milky spots stained by activated carbon on the 3rd day. In the diaphragm, cancer cells adhered to the small pores termed stomata, and invaded into the subdiaphragmatic lymphatic lacunae connected with stomata. From the 3rd day, mesothelial cells of the abdominal cavity became round and separated, resulting in the exposure of the underlying connective tissue. MKN-45-P cells were found to adhere to the naked areas of the submesothelial connective tissue. From these results, we conclude that the major metastatic route of the peritoneum may be firstly through milky spots, secondly through the diaphragmatic stomata, and thirdly by the adhesion to the naked connective tissue exposed after shrinkage of the mesothelial cells. The third process may be related to the interaction between some adhesion molecules and their ligands.

Roles of VLA-2 and VLA-3 on the formation of peritoneal dissemination in gastric cancer

To clarify the mechanisms of the metastasis on the peritoneal surface from gastric cancer, a novel ex vivo co-culture system using human greater omentum and a highly metastatic cell line, MKN-45-P was developed. MKN-45-P was established from a gastric cancer cell line of MKN-45 by the progressive growing of the intraperitoneal passages. The differences of the expression of metastasis related genes between MKN-45 and MKN-45-P were examined by RT-PCR. Cancer cells adhered only to the naked area of the submesothelial basement membrane, which was exposed by the shrinkage and exfoliation of mesothelial cells of the omentum. The expressions of integrin alpha 2 and alpha 3 subunits in MKN-45-P were extremely elevated compared to those in MKN-45. Integrin beta 1 subunit expression did not change during the intraperitoneal passages. Anti-beta 1 integrin subunit antibody significantly inhibited the adherent number of MKN-45-P on the omentum. These results indicate that VLA-2 and VLA-3 may have an important role in the formation of the peritoneal dissemination from gastric cancer.

Correlation between expression of urokinase-type plasminogen activator receptor and metastasis in gastric carcinoma

To clarify the interrelationship between urokinase-type plasminogen activator receptor (uPAR) and the progression of gastric cancer, uPAR expression in gastric cancer was studied by the reverse transcription (RT)-PCR and immunohistochemistry. uPAR mRNA was expressed in 44 of 46 primary gastric cancers and uPAR immunoreactivity was found in 21 (14%) of 155 tumors. uPAR immunoreactivity was also observed in the fibroblast-like cells and the inflammatory cells including macrophages. The intensity of uPAR immunoreactivity of these cells was weaker than that of cancer cells. uPAR expression detected by RT-PCR may be from cancer cells and/or non-cancerous stromal cells. uPAR immunoreactivity in cancer cells was closely associated with histologic type, nodal status, and macroscopic type. The uPAR positive tumors were closely associated with the macroscopically infiltrating type, undifferentiated type and stage IV disease. Poorly differentiated carcinomas with rich intestitial fibrosis (scirrhous carcinoma) expressed uPAR with a significantly higher incidence than the other histologic types of carcinoma. Growth of scirrhous carcinoma may be a result of a concerted action of the players in the plasminogen activator system, consisting of cancer cells and stromal elements. Furthermore, there was an intimate relationship between the grade of lymph node metastasis and uPAR tissue status. Patients with a uPAR positive tumor had a significantly poorer prognosis than those with uPAR negative tumor. These results indicate that the immunohistochemical diagnosis of uPAR tissue status on the primary tumor of gastric cancer may be a good predictor for the prognosis of patients with gastric cancer.

Two-qubit gate of combined single-spin rotation and interdot spin exchange in a double quantum dot

A crucial requirement for quantum-information processing is the realization of multiple-qubit quantum gates. Here, we demonstrate an electron spin-based all-electrical two-qubit gate consisting of single-spin rotations and interdot spin exchange in a double quantum dot. A partially entangled output state is obtained by the application of the two-qubit gate to an initial, uncorrelated state. We find that the degree of entanglement is controllable by the exchange operation time. The approach represents a key step towards the realization of universal multiple-qubit gates.

Degeneration of patellar cartilage in patients with recurrent patellar dislocation following conservative treatment: evaluation with delayed gadolinium-enhanced magnetic resonance imaging of cartilage

OBJECTIVE

To examine the characteristics of cartilage degeneration in patients with recurrent patellar dislocation (RPD) following conservative treatment using delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC).

DESIGN

This study evaluated three groups of knees: group I, 35 knees from both knees of patients with bilateral RPD and dislocated side knees of patients with unilateral RPD; group II, 15 non-dislocated side knees of patients with unilateral RPD; and group III, 20 knees from both knees of healthy volunteers. Differences in post-contrast T1 [T1(Gd)] of cartilage at both medial and lateral facets between groups I, II and III were analyzed. For group I, possible relationships were evaluated between T1(Gd) of cartilage and patient age, length of time between the initial dislocation and MRI and the total number of dislocations between the initial dislocation and MRI for both medial and lateral facets.

RESULTS

The mean T1(Gd) of cartilage at medial facets for groups I, II and III were 411+/-46ms, 465+/-38ms and 490+/-29ms, respectively; there were significant differences between these means (P<0.05). The mean T1(Gd) of cartilage at lateral facets for groups I, II and III were 426+/-53ms, 466+/-45ms and 510+/-36ms, respectively; there were also significant differences between these means (P<0.05). Significant correlations were observed between T1(Gd) of cartilage for both medial and lateral facets and length of time between the initial dislocation and MRI (P<0.05). No other correlations were significant.

CONCLUSION

dGEMRIC may be a useful method to monitor glycosaminoglycan concentration in patients with RPD following conservative treatment.

Visualization of in vivo electroporation-mediated transgene expression in experimental tumors by optical and magnetic resonance imaging

In vivo electroporation (EP) is an efficient method for effective gene transfer and is highly expected for application in anticancer gene therapy. Non-invasive monitoring of gene transfer/expression is critical for optimal gene therapy. Here we report in vivo optical and high-field magnetic resonance imaging (MRI) of EP-mediated transgene expression in a tumor model. Initially, we observed spatio-temporal change in in vivo EP-mediated transgene expression by optical imaging using red fluorescence protein (RFP) as a reporter gene. Next, we constructed a dual-reporter plasmid carrying a gene-encoding MRI reporter ferritin heavy chain and RFP gene to visualize the intratumoral transgene expression by dual modality. Cells transfected with this plasmid showed lower signal intensity on in vitro T(2)-weighted cellular MRI and quantitatively increased the transverse relaxation rate (1/T(2)) compared with control cells. After conducting in vivo EP in an experimental tumor, the plasmid-injected region showed both fluorescent emissions in optical imaging and detectably lowered signal on T(2)-weighted MRI. The correlative immunohistological findings confirmed that both the reporter transgenes were co-expressed in this region. Thus, our strategy provides a platform for evaluating EP-mediated cancer gene therapy easily and safely without administering contrast agent or substrate.

Antigenic stimulation with cytochrome P450 2J expressed in mouse hepatocellular carcinoma cells regulates host anti-tumour immunity

Cytochrome P450 2J subfamily (CYP2J) enzymes expressed in mouse hepatocellular carcinoma (HCC) cells were identified as an antigen recognized by specific CD4(+) T cells and the structure of its T cell epitope was determined by proteomics-based exploration. The major histocompatibility complex (MHC) class II binding peptides were isolated from I-A(k)/peptide complex of dendritic cells (DCs) loaded or unloaded with MIH-2 mouse HCC cells. MHC class II-binding peptides found in MIH-2-loaded DCs but not in unloaded DCs were determined by tandem mass spectrometric analysis. The peptide, consisting of amino acid 276-290 (DFIDAFLKEMTKYPE) of mouse CYP2J enzymes, was identified as an antigenic peptide presented in the context of MHC class II. Preventive treatment of mice with CYP2J peptide stimulated interferon (IFN)-gamma production of splenocytes and suppressed the growth of implanted CYP2J-positive MIH-2 cells but not CYP2J-negative murine bladder tumour cells. However, continuous treatment of MIH-2-bearing mice with CYP2J peptide significantly suppressed IFN-gamma production of splenocytes and accelerated the growth of implanted MIH-2 tumours in vivo. Increased frequencies of CD4(+)forkhead box P3 regulatory T cells and CD11b(+)Gr-1(+) myeloid suppressor cells were observed in splenocytes from the continuously immunized mice. These results indicate that antigenecity of CYP2J isoforms expressed in HCC cells activate host anti-tumour immunity at an initial stage of HCC, but suppress host anti-tumour immunity with excessive antigenic stimulation at an advanced stage.

Early detection of the Limulus amebocyte lysate reaction evoked by endotoxins

The gelation of Limulus amebocyte lysate (LAL) evoked by bacterial endotoxins can be detected earlier than with usual methods by using laser scattering photometry to recognize the formation of small particles of clotted enzyme produced when the reaction mixture is agitated. The appearance of these small particles means that the influence of endotoxins has stimulated activation of the clotting enzyme across the LAL cascade, and the timing of their appearance is related to endotoxin concentration. This new method can be used for quick and sensitive endotoxin assay. The average endotoxin level of healthy volunteers was assayed to be 0.0738 pg/ml [0.0312-0.3445 pg/ml] (n = 11) within 70 min from the start of the assay.

Nitric oxide and MPP+-induced hydroxyl radical generation

Although neuroprotective effect of nitric oxide (NO) is discussed, NO has a role of pathogenesis of cellular injury. NO is synthesized from L-arginine by NO synthase (NOS). NO contributes to the extracellular potassium-ion concentration ([K(+)](o))-induced hydroxyl radical ((*)OH) generation. Cytotoxic free radicals such as peroxinitrite (ONOO(-)) and (*)OH may also be implicated in NO-mediated cell injury. NO activation was induced by K(+) depolarization. NO may react with superoxide anion (O(2) (-)) to form ONOO(-) and its decomposition generates (*)OH. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) metabolite 1-methyl-4-phenylpyridinium ion (MPP(+)) involve toxicity induced by NO. Intraneuronal Ca(2+) triggered by MPP(+) may be detrimental to the functioning of dopaminergic nerve terminals in the striatum. Although the [K(+)](o)-induced depolarization enhances the formation of (*)OH product due to MPP(+), the (*)OH generation via NOS activation may be unrelated the dopamine (DA)-induced (*)OH generation. Depolarization enhances the MPP(+)-induced (*)OH formation via NOS activation. NOS inhibition is associated with a protective effect due to suppression of depolarization-induced (*)OH generation. ONOO(-) has been implicated as a causative factor under conditions in which DA neurons are damaged. These findings may be useful in elucidating the actual mechanism of free radical formation in the pathogenesis of neurodegenerative brain disorders, including Parkinson's disease and traumatic brain injuries.

Proton magnetic resonance imaging of flow motion of heavy water injected into a hollow fiber dialyzer filled with saline

Observations using MRI were performed for the motion of heavy water injected into a hollow fiber dialyzer. A cylindrical dialyzer houses a bundle of 10,000 hollow fibers. Because blood components permeate through the hollow fiber membrane from the interior to the exterior of the hollow fiber, which is the dialysate flow path, uniformity of dialysate flow is required. The dialyzer was initially filled with saline and heavy water was injected into the inlet port of the dialysate flow path. MRI tuned for protons could distinguish the injected heavy water from the already present saline. Due to the specific gravity difference, MRI could observe the sedimentation of the injected heavy water flowing beneath the already present saline. The uniformity of the dialysate flow was supported by the finding that the injected heavy water brought about uniform sedimentation and distributed the already present saline uniformly throughout the entire volume of the dialyzer.

Detection of small degree of nonuniformity in dialysate flow in hollow-fiber dialyzer using proton magnetic resonance imaging

A small degree of nonuniformity in dialysate flow in a hollow-fiber dialyzer was detected using proton magnetic resonance imaging (MRI). Since paramagnetic ions reduce the spin-lattice relaxation time of protons around them, MRI can detect Gd in water. An aqueous solution of a chelate compound of Gd was impulsively injected into the dialysate flow path at a flow rate of 500 cm(3) /m, which is that utilized in actual dialysis. Despite the apparent elimination of Gd from the dialysate flow path by the newly injected dialysate fluid after the injection of Gd was terminated, MRI revealed that Gd remained in the interior of the hollow fiber. The observed structure pattern of the Gd concentration profile revealed that the dialysate flow had a small degree of nonuniformity despite the currently established design to restrict channeling in dialysate flow. Local nonuniformity of the hollow-fiber density and vortex generation in the dialysate flow were considered to cause the nonuniformity in the dialysate flow.