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We report the case of a 16-year-old boy in whom we successfully repaired a distal aortic arch aneurysm associated with pseudocoarctation using double aortic cannulation and antegrade selective cerebral perfusion through the L-incision approach. This approach provided excellent exposure from the ascending aorta to the descending aorta, which enabled total body perfusion. We avoided cardiac arrest and hypothermic circulatory arrest during the surgery. The L-incision approach could be a better alternative for aortic arch surgery in adolescents., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery.)

Aims: Junctional ectopic tachycardia (JET) after cardiopulmonary bypass surgery for congenital heart defects is often therapy-resistant and associated with high morbidity and mortality. Improvement of pharmacological therapy is needed., Methods and Results: We retrospectively analysed the clinical data of four patients with congenital heart defects, who developed post-operative JET and were treated with landiolol hydrochloride, representing all such patients treated at our university. In two patients, landiolol was used after failure of response to anti-arrhythmic therapies, including thermal control, sedation, discontinuation of catecholamines, and pharmacological therapy with nifekalant and amiodarone. Landiolol was used as a first-line therapy in the other two patients. In all patients, landiolol, at a dose ranging from 1.0 to 10.0 µg/kg/min, achieved successful sinus conversion within 15 min. No adverse events, such as bradycardia, hypotension, or hypoglycaemia, were encountered in all four patients., Conclusion: Although limited to a small and heterogeneous group of patients, the results suggest that landiolol is a potentially useful therapeutic option for the well-known difficult condition of post-operative JET, and warrant further investigation in large-scale controlled studies.

For the safe clinical application of embryonic stem cells (ESCs) for neurological diseases, it is critical to evaluate the tumorigenicity and function of human ESC (hESC)-derived neural cells in primates. We have herein, for the first time, compared the growth and function of hESC-derived cells with different stages of neural differentiation implanted in the brains of primate models of Parkinson's disease. We herein show that residual undifferentiated cells expressing ESC markers present in the cell preparation can induce tumor formation in the monkey brain. In contrast, a cell preparation matured by 42-day culture with brain-derived neurotrophic factor/glial cell line-derived neurotrophic factor (BDNF/GDNF) treatment did not form tumors and survived as primarily dopaminergic (DA) neurons. In addition, the monkeys with such grafts showed behavioral improvement for at least 12 months. These results support the idea that hESCs, if appropriately matured, can serve as a source for DA neurons without forming any tumors in a primate brain., (Copyright © 2012 AlphaMed Press.)

Objectives: Recent studies have linked abnormal aortic medial pathology to progressive aortic root dilatation in patients with tetralogy of Fallot (TOF). To explore whether the aortic medial pathology in TOF is linked to aortic mechanical property, the present study tested the hypothesis that the distribution of impaired aortic elasticity corresponds to the known distribution of abnormal medial pathology (confined to the ascending aorta) in TOF., Methods: Pulse wave velocity (PWV) of the proximal and distal aortas was measured with a high-fidelity micromanometer in 98 TOF patients (64 with repaired TOF and 34 with unrepaired TOF) and 63 control subjects., Results: PWV of the proximal aorta was significantly higher in TOF than in the control, but similar in repaired and unrepaired TOF (repaired: 588 ± 205 cm/s, unrepaired: 680 ± 288 cm/s, control: 439 ± 101 cm/s, P < 0.001 for each TOF group vs. control, P = 0.07 for repaired vs. unrepaired TOF). In contrast, PWV of the distal aorta was almost identical among the three groups (repaired: 441 ± 189 cm/s, unrepaired: 430 ± 114 cm/s, control: 461 ± 164 cm/s, P = 0.73, analysis of variance), indicating that abnormal aortic mechanical property is confined to the proximal aorta regardless of the operative status of TOF. This was also confirmed by comparison within the group; PWV of the proximal aorta was significantly higher than that of the distal aorta in both TOF groups (P < 0.001, each), whereas there was no difference in PWV between the proximal and distal aortas in the control subjects (P = 0.61)., Conclusions: Consistent with the known histopathological disparity between the media of the ascending and descending aortas, aortic stiffness is markedly increased in the proximal but not in the distal aorta of TOF. These results suggest that aortic wall stiffness is a potentially useful clinical marker of aortic dilation in patients with TOF.

Aims: (i) Quantitative and qualitative analyses of photosynthetic metabolites of Chlorella sorokiniana and elucidation of the mechanism of their utilization by algal symbionts. (ii) Development of artificial medium that imitates photoautotroph-heterotroph interaction and investigation of its suitability for isolation of novel microbes from the environment., Methods and Results: Various components, including free dissolved carbohydrates, nitrogenous compounds and vitamin, were detected and together contributed 11.1% (as carbon content) of the total photosynthetic metabolites in the medium. Utilization of these photosynthetic metabolites in algal culture broth by algal symbionts was studied. Many symbionts showed specific utilization patterns. A novel artificial extracellular released organic carbon medium, which imitated the nutritional conditions surrounding algae, was developed based on the pattern of utilization of the algal metabolites by the symbiotic heterotrophs. About 42.9% of the isolates were closely related to photoautotrophic-dependent and oligotrophic bacteria., Conclusions: With the novel artificial medium, it was possible to selectively isolate some bacterial strains., Significant and Impact of the Study: Synthetic bacterial growth medium is an important and basic tool for bacterial isolation from environmental samples. The current study shows that preferential separation of typical bacterial subset can be achieved by using artificial medium that mimics photosynthetic metabolites.

Aims: To investigate the chemical characterization of the mucilage sheath produced by Chlorella sorokiniana., Methods and Results: Algal mucilage sheath was hydrolysed with NaOH, containing EDTA. The purity of the hydrolysed sheath was determined by an ATP assay. The composition of polysaccharide in the sheath was investigated by high-performance anion-exchange chromatography with pulsed amperometric detection. Sucrose, galacturonic acid, xylitol, inositol, ribose, mannose, arabinose, galactose, rhamnose and fructose were detected in the sheath as sugar components. Magnesium was detected in the sheath as a divalent cation using inductively coupled argon plasma. The sheath matrix also contained protein., Conclusions: It appears that the sheath is composed of sugars and metals. Mucilage sheath contains many kinds of saccharides that are produced as photosynthetic metabolites and divalent cations that are contained in the culture medium., Significance and Impact of the Study: This is the first report on chemical characterization of the sheath matrix produced by C. sorokiniana.

Chlorella sorokiniana IAM C-212 has long been maintained in slant culture as a mixed strain, representing an associated natural microbial consortium. In this study, the consortium was separated and five nonalgal constituents, a fungal strain (CSSF-1), and four bacterial strains (CSSB-1, CSSB-2, CSSB-3, and CSSB-4) were isolated and identified. 16S rDNA sequence analysis revealed that strains CSSB-1, CSSB-2, CSSB-3, and CSSB-4 were close to Ralstonia pickettii (99.8% identity), Sphingomonas sp. DD38 (99.4% identity), Microbacterium trichotecenolyticum (98.6% identity), and Micrococcus luteus (98.6% identity) respectively. 18S rDNA sequence analysis revealed that strain CSSF-1 resembled Acremonium-like hyphomycete KR21-2 (98.8%). The fungal strain CSSF-1 and one of the bacterial strains, CSSB-3, were found to promote the growth of Chlorella while the presence of bacterial strains CSSB-1 and CSSB-2 had no effect. Strain CSSB-4 could not be subcultured so its role was not elucidated. These results show that the interaction between Chlorella and its symbionts under photoautotrophic conditions involved both mutualism and commensalisms. The chlorophyll content of mixed strain was stable in long-term cultivation (7 months) while the chlorophyll content of a pure culture showed a marked decline. Electron microscopic analysis showed the two bacterial strains CSSB-2 and CSSB-3 were harbored on the sheath excreted by Chlorella, while the fungal strain CSSF-1 and the bacterial strain CSSB-1 directly adhered to the Chlorella cell surface. This report is the first observation of a symbiotic relationship among fungus, bacteria, and Chlorella, and the first observation of direct adhesion of fungus and bacteria to Chlorella in a consortium.

New phenol degrading bacteria with high biodegradation activity and high tolerance were isolated as Burkholderia cepacia PW3 and Pseudomonas aeruginosa AT2. Both isolates could grow aerobically on phenol as a sole carbon source even at 3 g/l. The whole-cell kinetic properties for phenol degradation by strains PW3 and AT2 showed a Vmax of 0.321 and 0.253 mg/l/min/(mg protein), respectively. The metabolic pathways for phenol biodegradation in both strains were assigned to the meta-cleavage activity of catechol 2,3-dioxygenase.

Among the members of the copper protein superfamily, the type I enzyme rusticyanin, which is found as an electron carrier in the oxidative respiratory chain of Acidithiobacillus ferrooxidans, is the only one to have both a high redox potential and acid stability. Here we report that two forms of the rusticyanin gene (rus) are present in the genomes of some strains of A. ferrooxidans. The more common form of rus (type-A) was found to be present in all six strains studied, including those harboring only a single copy of the gene. In addition a less common form (type-B) occurred in strains harboring multiple copies of the gene. The two genes were expressed as rusticyanin isozymes with differing surface charges due to differences in their amino acid composition. Still, the copper coordination sites were completely conserved, thereby maintaining the high redox potential necessary for an electron carrier.

Hydrogenobacter acidophilus strain 3H-1 is a thermoacidophilic, obligately chemolithoautotrophic, hydrogen-oxidizer isolated from a Japanese solfataric field. Strain 3H-1 requires elemental sulfur for growth. We used PCR to amplify the 16S rRNA gene of strain 3H-1, and sequenced the amplification product directly. Phylogenetic analyses show strain 3H-1 is closely related to Aquifex pyrophilus and may be located in the deepest branch within the eubacterial phylogenetic tree. Sulfur-dependency of the ancestral eubacterium is also discussed.