It is believed that intracellular carbonic anhydrases (CAs) are essential components of carbon concentrating mechanisms in microalgae. In this study, putative CA-encoding genes were identified in the genome sequences of the marine diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana. Subsequently, the subcellular localizations of the encoded proteins were determined. Nine and thirteen CA sequences were found in the genomes of P. tricornutum and T. pseudonana, respectively. Two of the β-CA genes in P. tricornutum corresponded to ptca1 and ptca2 identified previously. Immunostaining transmission electron microscopy of a PtCA1:YFP fusion expressed in the cells of P. tricornutum clearly showed the localization of PtCA1 within the central part of the pyrenoid structure in the chloroplast. Besides these two β-CA genes, P. tricornutum likely contains five α- and two γ-CA genes, whereas T. pseudonana has three α-, five γ-, four δ-, and one ζ-CA genes. Semi-quantitative reverse transcription PCR performed on mRNA from the two diatoms grown in changing light and CO(2) conditions revealed that levels of six putative α- and γ-CA mRNAs in P. tricornutum did not change between cells grown in air-level CO(2) and 5% CO(2). However, mRNA levels of one putative α-CA gene, CA-VII in P. tricornutum, were reduced in the dark compared to that in the light. In T. pseudonana, mRNA accumulation levels of putative α-CA (CA-1), ζ-CA (CA-3) and δ-CA (CA-7) were analyzed and all levels found to be significantly reduced when cells were grown in 0.16% CO(2). Intercellular localizations of eight putative CAs were analyzed by expressing GFP fusion in P. tricornutum and T. pseudonana. In P. tricornutum, CA-I and II localized in the periplastidial compartment, CA-III, VI, VII were found in the chloroplast endoplasmic reticulum, and CA-VIII was localized in the mitochondria. On the other hand, T. pseudonana CA-1 localized in the stroma and CA-3 was found in the periplasm. These results suggest that CAs are constitutively present in the four chloroplastic membrane systems in P. tricornutum and that CO(2) responsive CAs occur in the pyrenoid of P. tricornutum, and in the stroma and periplasm of T. pseudonana.
Sleep apnea syndrome (SAS) is basically divided into two types: obstructive and central SAS. Recently, the concept of complex SAS has been advocated. Complex SAS is defined as SAS that initially manifests as primarily obstructive SAS, but is characterized by the frequent central apneas after the removal of upper airway obstruction. To determine the prevalence and clinical significance of complex SAS among Japanese patients with SAS, 1,312 patients with SAS were enrolled in this study. Diagnosis of central SAS was made based on diagnostic polysomnography, and differentiation of obstructive SAS from complex SAS was made from polysomnographic findings for treatment with continuous positive airway pressure, which resolved upper airway obstruction. As a result, obstructive SAS was found in 1,232 of 1,312 patients with SAS (93.9%) and central SAS was found in 14 patients (1.1%). The overall prevalence of complex SAS was 5.0% (n = 66). The prevalence of complex SAS among 1,218 male and 94 female patients with SAS were 5.3% and 1.1%, respectively. Patients with complex SAS had significantly higher apnea/ hypopnea indices than patients with either obstructive or central SAS, but were similar in both mean age and average body mass index to obstructive SAS patients. There were no significant between-group differences in numbers of patients with clinical complications including hypertension, cardiac diseases, or cerebrovascular diseases. In conclusion, the prevalence of complex SAS in Japanese SAS patients is 5.0%, which is lower than previously reported prevalence of complex SAS in the USA and Australia. obstructive sleep apnea syndrome; central sleep apnea syndrome; hypertension; cardiac disease; cerebrovascular disease.
Background The number of adolescent patients with anorexia nervosa is increasing. In addition, an increase in pre‐adolescent patients with premenarchal onset has also been recognized. Detection of the disease in childhood and adolescence, however, is not always easy because the symptoms are not characteristic during this period. This study was performed to investigate detection of anorexia nervosa in children/adolescents by comparing energy and nutrient intake between patients with anorexia nervosa and healthy thin persons. Methods The subjects consisted of 13 girls aged 14.4 ± 3.5 years with anorexia nervosa and 320 healthy girls aged 12.4 ± 1.3 years. Dietary intake was evaluated using a validated diet history questionnaire designed for children/adolescents. Daily energy and nutrient intake were expressed as a percentage of the age‐ and sex‐matched reference amount. Results Healthy lean (body mass index [BMI], <50th percentile) girls with an above‐average score for desiring thinness had higher fat and lower cereal intake, and a trend of lower carbohydrate intake. In contrast, patients with anorexia nervosa, compared with thin (BMI <5th percentile) girls, characteristically had significantly lower energy, fat, zinc, vitamin C, and confectionery intake. Conclusions Lean girls with an above‐average desire for thinness appear to restrict their energy intake by reducing their intake of carbohydrates such as cereals while maintaining a relatively high fat intake. In contrast, girls with anorexia nervosa avoided fat and had a preference for vegetables. This characteristic eating pattern could be a useful clue for detection of anorexia nervosa in thin children and adolescents.
Using the picture choice method, definite gender differences in food preference were identified in early elementary school children. This information could be useful for dietary therapy in childhood obesity.
Grain boundaries are well known to be the predominant pinning centers in MgB 2 superconductors. To study the effects of grain boundaries on the trapped field properties of MgB 2 bulk, we prepared MgB 2 bulks by a spark plasma sintering method using a ball-milled starting powder. The trapped field was maximized for the bulk made from the ball-milled powder with crystallite size, τ, of 27 nm; the highest trapped field, B T , of 2.3 T achieved at 19.3 K was 1.2 times larger than that of the bulk made from the non ball-milled powder (τ = 50 nm). The degradation of the trapped field for the bulk from finer powder (τ = 6 nm) originated mainly from the lowered T c. The critical current density, J c , and the pinning force density, F p , were also maximized for the bulk from τ = 27 nm. The competition between the increase of the numerical density of grain boundaries and the degradation of superconductivity determined the vortex pinning properties for the MgB 2 bulks with mechanically refined grains. The scaling analysis for the pinning force density suggested that the change in the dimension of the dominant pinning source from 2D (surface) to 0D (point) was induced by grain refining. Although the nanometric impurity particles such as MgB 4 , MgO and Mg-B-O were created in the bulk during both ballmilling and spark plasma sintering processes, we considered the point-contact between the refined grains was the predominant point pinning source.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.