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1.
Leg Med (Tokyo) ; 71: 102529, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39293287

RESUMEN

Despite the increased global mobility owing to the development of the international community, there remains a need for population-specific methods to estimate children's ages. Therefore, this study aimed to substantiate the necessity for a Japanese-specific age estimation method by contrasting the formerly reported age estimation accuracy and bias using Demirjian's method for Chinese, Taiwanese, South Korean, and Japanese children. We analyzed 1,558 panoramic radiographs from Japanese children (777 boys and 781 girls), assessed the maturity of seven left permanent teeth using Demirjian's criteria, and calculated the estimated age using Demirjian's method. The accuracy of the estimated ages was compared with previous reports of children from other East Asian countries which used the same age estimation method. Chinese, Taiwanese, and South Korean boys and girls were all reported to be older than their chronological ages, with the Eastern and Northern Chinese regions being the only exceptions. The same was true for Japanese children: the estimated ages of both sexes tended to be higher than their chronological age. However, there were significant variations in the values, indicating the differences in tooth growth and development between East Asian countries and sexes. Therefore, new regression equations specific to the Japanese population were formulated, and their accuracy was evaluated as the final result of this study.

2.
Adv Sci (Weinh) ; : e2403587, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39206711

RESUMEN

Copper (Cu) is widely used as an industrial electrode due to its high electrical conductivity, mechanical properties, and cost-effectiveness. However, Cu is susceptible to corrosion, which degrades device performance over time. Although various methods (alloying, physical passivation, surface treatment, etc.) are introduced to address the corrosion issue, they can cause decreased conductivity or vertical insulation. Here, using the nitrogen-doped amorphous carbon (a-C:N) thin film is proposed as a substrate on which Cu is directly deposited. This simple method significantly inhibits corrosion of ultrathin Cu (<20 nm) films in humid conditions, enabling the fabrication of ultrathin electronic circuit boards without corrosion under ambient conditions. This study investigates the origin of corrosion resistance through comprehensive microscopic/spectroscopic characterizations and density-functional theory (DFT) calculations: i) diffusion of Cu atoms into the a-C:N driven by stable C-Cu-N bond formation, ii) diffusion of N atoms from the a-C:N to the Cu layer heading the top surface, which is the thermodynamically preferred location for N, and iii) the doped N atoms in Cu layer suppress the inclusion of O into the Cu lattice. By leveraging the ultrathinness and deformability of the circuit board, a transparent electrode and a crumpleable LED lighting device are demonstrated.

3.
Artículo en Inglés | MEDLINE | ID: mdl-39207221

RESUMEN

Two novel bacteria, MJ-SS3T and MJ-SS4, were isolated from tidal flat sediment sampled in Gochang, Republic of Korea. The isolates were Gram-stain-negative, aerobic, non-motile, rod-shaped, yellow-coloured, oxidase-positive, and catalase-positive. Strains MJ-SS3T and MJ-SS4 grew at 20-37 °C (optimum, 30 °C), at pH 6-8 (optimum, pH 7.0) and in the presence of 0-7 % (w/v) NaCl (optimum, 2.0 % NaCl). Strains MJ-SS3T and MJ-SS4 showed 99.9 % 16S rRNA gene sequence similarity. Phylogenetic analysis based on genome and 16S rRNA gene sequences indicated that strains MJ-SS3T and MJ-SS4 were affiliated with the family Flavobacteriaceae and most closely related to Formosa maritima 1494T (95.3 %), Hanstruepera flava NBU2984T (95.2 %), Yeosuana marina JLT21T (95.2 %), Meridianimaribacter flavus NH57NT (95.1 %), and Geojedonia litorea YCS-16T (95.1 %). The major respiratory quinone was menaquinone-6. The major identified polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and amino lipids. The major cellular fatty acids of strain MJ-SS3T were iso-C15 : 1 G (24.6 %), iso-C15 : 0 (21.6 %), and iso-C17 : 0 3-OH (15.8 %). The genome length of strain MJ-SS3T is 3.1 Mbp (DNA G+C content, 32.5 mol%) and it has 2822 coding and 59 tRNA genes. The average amino acid identity and average nucleotide identity values, as well as biochemical, phylogenetic, and physiological characteristics, strongly supported the genotypic and phenotypic differentiation of strains MJ-SS3T and MJ-SS4 from other members of the family Flavobacteriaceae. Hence, strains MJ-SS3T and MJ-SS4 are considered to represent a novel species of a new genus in the family Flavobacteriaceae, for which the Gilvirhabdus luticola gen. nov., sp. nov. is proposed. The type strain is MJ-SS3T (=KCTC 102114T=KEMB 20189T=JCM 36595T), with reference strain MJ-SS4 (=KCTC 102115=KEMB 20190).


Asunto(s)
Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano , Ácidos Grasos , Flavobacteriaceae , Sedimentos Geológicos , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Vitamina K 2 , Sedimentos Geológicos/microbiología , ARN Ribosómico 16S/genética , Ácidos Grasos/química , República de Corea , ADN Bacteriano/genética , Vitamina K 2/análogos & derivados , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Flavobacteriaceae/clasificación , Cloruro de Sodio/metabolismo , Agua de Mar/microbiología
4.
ACS Omega ; 9(32): 34259-34267, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39157099

RESUMEN

Ruegeria atlantica and Pseudoalteromonas neustonica are fish gut bacteria that have been isolated from the guts of Pagrus major and Acanthopagrus schlegelii, respectively. A total of 22 compounds (1-22) were isolated from these two bacteria; 16 compounds (1-16) from R. atalantica and 6 compounds (17-22) from P. neustonica. Their chemical structures were elucidated by spectroscopic and spectrometric data analysis and chemical synthesis. Compounds 11 and 13 showed strong collagenase inhibitory activity, with 31.91% and 36.43% at 20 µM, respectively, comparable to or surpassing that of the positive control epigallocatechin gallate (EGCG, 34.66%). Also, compounds 11 and 14 exhibited a mild tyrosinase inhibitory effect of 6.73% and 13.68%, respectively. All of the tested compounds displayed no significant antibacterial activity against Escherichia coli and Bacillus subtilis up to 100 µM. The collagenase- and tyrosinase-inhibitory compound 11, cyclo(l-Pro-d-Leu), was found to be stable under heat (50 °C) and UV light (254 and 365 nm) for up to 6 days. These results indicate that compound 11 could be developed into a cosmeceutical with antiaging effects.

5.
J Fungi (Basel) ; 10(8)2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39194882

RESUMEN

Exploring species diversity along elevational gradients is important for understanding the underlying mechanisms. Our study focused on analyzing the species diversity of fungal communities and their subcommunities at different trophic and taxonomic levels across three high mountains of the Korean Peninsula, each situated in a different climatic zone. Using high-throughput sequencing, we aimed to assess fungal diversity patterns and investigate the primary environmental factors influencing fungal diversity. Our results indicate that soil fungal diversity exhibits different elevational distribution patterns on different mountains, highlighting the combined effects of climate, soil properties, and geographic topology. Notably, the total and available phosphorus contents in the soil emerged as key determinants in explaining the differences in diversity attributed to soil properties. Despite the varied responses of fungal diversity to elevational gradients among different trophic guilds and taxonomic levels, their primary environmental determinants remained remarkably consistent. In particular, total and available phosphorus contents showed significant correlations with the diversity of the majority of the trophic guilds and taxonomic levels. Our study reveals the absence of a uniform diversity pattern along elevational gradients, underscoring the general sensitivity of fungi to soil conditions. By enriching our understanding of fungal diversity dynamics, this research enhances our comprehension of the formation and maintenance of elevational fungal diversity and the response of microbial communities in mountain ecosystems to climate change. This study provides valuable insights for future ecological studies of similar biotic communities.

6.
Adv Sci (Weinh) ; 11(24): e2309819, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582505

RESUMEN

Exsolution is an effective method for synthesizing robust nanostructured metal-based functional materials. However, no studies have investigated the exsolution of metal nanoparticles into metal nitride substrates. In this study, a versatile nitridation-driven exsolution method is developed for embedding catalytically active metal nanoparticles in conductive metal nitride substrates via the ammonolysis of multimetallic oxides. Using this approach, Ti1-xRuxO2 nanowires are phase-transformed into holey TiN nanotubes embedded with exsolved Ru nanoparticles. These Ru-exsolved holey TiN nanotubes exhibit outstanding electrocatalytic activity for the hydrogen evolution reaction with excellent durability, which is significantly higher than that of Ru-deposited TiN nanotubes. The enhanced stability of the Ru-exsolved TiN nanotubes can be attributed to the Ru nanoparticles embedded in the robust metal nitride matrix and the formation of interfacial Ti3+─N─Ru4+ bonds. Density functional theory calculations reveal that the exsolved Ru nanoparticles have a lower d-band center position and optimized hydrogen affinity than deposited Ru nanoparticles, indicating the superior electrocatalyst performance of the former. In situ Raman spectroscopic analysis reveals that the electron transfer from TiN to Ru nanoparticles is enhanced during the electrocatalytic process. The proposed approach opens a new avenue for stabilizing diverse metal nanostructures in many conductive matrices like metal phosphides and chalcogenides.

7.
Leg Med (Tokyo) ; 66: 102363, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38065055

RESUMEN

The nose is a prominent feature for facial recognition and reconstruction. To investigate the relationship of the nasal shape with the piriform aperture in Korean adults and juveniles, we performed regression analysis. By regression analysis, prediction equations for nasal shape were obtained in relation to the shape of the piriform aperture considering sex and age groups. Three-dimensional skull and face models, rendered from computed tomography images, were assessed (331 males and 334 females). Juveniles (<20 years) were divided into three age groups according to the development of the dentition. Adults were divided into three age groups of two decades each, according to their age. To measure the nasal area, nine landmarks and nine measurements were chosen, while seven landmarks and five measurements were selected to measure the piriform aperture area. Four measurements were defined to explain the direct relationship between the nasal aperture and nasal shape. First, descriptive statistical analyses were performed according to sex and age groups. Subsequently, the correlation of nasal soft tissue measurements with piriform measurements was analyzed. Last, we performed a linear regression analysis of the measurements with higher correlations, considering sex and age groups as variables. Prediction equations were used to estimate the nasal bridge length, height, protrusion, and width. Equations considering sex and age groups showed better explanation ability. Measurements related to the height of the nasal bridge presented improvement. This study may assist in the more accurate approximation of nasal shape in facial reconstruction.


Asunto(s)
Antropología Forense , Imagenología Tridimensional , Adulto , Masculino , Femenino , Humanos , Antropología Forense/métodos , Nariz/diagnóstico por imagen , Nariz/anatomía & histología , Análisis de Regresión , Cráneo/anatomía & histología
8.
Heliyon ; 9(9): e19957, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809684

RESUMEN

This cross-sectional study aimed to evaluate the applicability of the London Atlas for age estimation in the Korean population by comparing with Lee's and Willems' methods. Dental ages of 475 orthopantomographs from Korean individuals aged 4-15 years (mean 10.32 ± 3.31 years) were estimated using the London Atlas, Lee's and Willems' methods. Correlation between dental and chronological age was determined using Pearson's correlation coefficient, and the statistical difference between dental and chronological age was analyzed using a paired t-test. The bias (mean differences), mean absolute error, and root mean square error between dental and chronological age, stratified by age groups and estimation methods, were calculated. Differences in bias and absolute error between sexes were scrutinized using an independent-samples t-test. Age estimates of the three tested methods were combined and compared to those of each individual method. The London Atlas and Willems methods resulted in overestimations, whereas the Lee method led to an underestimation on the entire sample. The overall accuracy was observed in the order of Lee's method, the London Atlas, and Willems' method. The London Atlas demonstrated superior consistency of estimation performance across age groups and no significant differences in estimation performance between sexes. The combination of estimates from the London Atlas and Lee's method resulted in an enhancement in bias and accuracy. We conclude that the London Atlas, due to its bias and accuracy comparable to Lee's and Willems' methods, is applicable for forensic practice in the Korean population.

9.
J Am Chem Soc ; 145(41): 22620-22632, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37799086

RESUMEN

Nanostructured silicon with an equilibrium shape has exhibited hydrogen evolution reaction activity mainly owing to its high surface area, which is distinct from that of bulk silicon. Such a Wulff shape of silicon favors low-surface-energy planes, resulting in silicon being an anisotropic and predictably faceted solid in which certain planes are favored, but this limits further improvement of the catalytic activity. Here, we introduce nanoporous silicon nanosheets that possess high-surface-energy crystal planes, leading to an unconventional Wulff shape that bolsters the catalytic activity. The high-index plane, uncommonly seen in the Wulff shape of bulk Si, has a band structure optimally aligned with the redox potential necessary for hydrogen generation, resulting in an apparent quantum yield (AQY) of 12.1% at a 400 nm wavelength. The enhanced light absorption in nanoporous silicon nanosheets also contributes to the high photocatalytic activity. Collectively, the strategy of making crystals with nontypical Wulff shapes can provide a route toward various classes of photocatalysts for hydrogen production.

10.
Anat Cell Biol ; 56(4): 474-481, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37694294

RESUMEN

The dental characteristics created by acquired dental treatments can be used as age estimators. This pilot study aimed to analyze the correlation between the number of teeth observed for dental characteristics and chronological age and to develop new non-invasive age estimation models. Dental features on panoramic radiographs (420 radiographs of subjects aged 20-89 years) were classified and coded. The correlation between the number of teeth for each selected code (codes V, X, T, F, P, and L) and age was observed, and multiple regression was performed to analyze the relationship between them. Eleven regression models with various combinations of dental sextants were presented. The model with the data from both sides of the posterior teeth on both jaws showed the best performance (root mean square error of 14.78 years and an adjusted R2 of 0.461). The model with all teeth was the second-best. Based on these results, we confirmed statistically significant correlations between certain dental features and chronological age. We also observed that some regression models performed sufficiently well to be used as adjunctive methods in forensic practice. These results provide valuable information for the design and performance of future full-scale studies.

11.
J Korean Med Sci ; 38(32): e245, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37582495

RESUMEN

BACKGROUND: Catecholamines consisting of epinephrine (EP), norepinephrine (NE), and dopamine (DA) are known as a class of chemical neurotransmitters and hormones essential for regulation of physiological processes including stress responses. Many researchers have tried to establish a relationship between postmortem catecholamine level and agony time or underlying cause of death. However, relevant studies have yielded debatable results. This study was performed to determine characteristics of catecholamine distribution in postmortem specimens with various influencing factors and to assess relationships of postmortem catecholamine levels with agony time and cause of death. METHODS: A total of 114 autopsy cases were analyzed for catecholamine levels and EP/NE ratios in femoral blood, heart blood, and urine specimens. Postmortem catecholamine levels according to sex, age, medical treatments (cardiopulmonary resuscitation [CPR] and EP injection), postmortem interval (PMI), agonal period, manner of death, and cause of death were evaluated. RESULTS: Close mutual relationships were noted among femoral and heart blood catecholamine levels. There was no correlation between blood and urine catecholamine levels. Catecholamine levels showed no significant differences according to sex, age, or manner of death. Heart EP and heart EP/NE ratio were significantly higher in the group with CPR. Femoral DA, heart EP, heart NE, heart DA, and urine DA were significantly increased in the group with EP injection. Urine NE and urine DA showed significant differences among PMI groups, with both increased over PMI. In correlation analysis, femoral DA and urine NE displayed weak correlations with PMI. Regarding agony time, femoral and heart DA were significantly increased in long agony group compared to those in the short agony group. With regard to the cause of death, multiple comparison analysis for major categories (natural death, injury, intoxication, asphyxia, drowning, and fire death) revealed a significant increase of femoral NE in asphyxia in comparison with injury. In subgroup analysis for the group without EP injection, femoral NE (P = 0.048), femoral DA (P = 0.039), and heart EP (P = 0.021) showed significant differences between PMI groups. CONCLUSION: Results of this study have important implications for understanding postmortem catecholamine distribution and their mutual associations, influences of clinical and demographic factors, and relationships with agony time and cause of death in Korean population. Although comprehensive demonstration of catecholamine level as stress index was not possible in the present study, the assessment of postmortem catecholamine levels could be used as a supportive tool in classification of agonal status and differential diagnosis of the cause of death in particular cases. Further investigation is needed on this issue.


Asunto(s)
Asfixia , Catecolaminas , Humanos , Autopsia , Causas de Muerte , Catecolaminas/orina , Epinefrina , Norepinefrina , Dopamina
12.
Heliyon ; 9(3): e13680, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36873551

RESUMEN

Third molar maturity is one of the major criteria for estimating human age. This study aimed to determine the most suitable third molar maturity criteria for age estimation in Koreans. The correlation between chronological age and the Demirjian, Köhler, Liversidge, and Thevissen criteria was evaluated using 900 panoramic radiographs of patients aged 15-23 years. The four criteria were applied separately to measure third molar maturity on the same radiograph. The concordance rates between third molars within the same jaw and between jaws were calculated and tested using a paired t-test. Regression was performed to observe the relationship between age and the evaluated stages for each tested criterion. The Demirjian standard showed the lowest root mean square error (1.29 years for males, 1.30 years for females) and highest adjusted R 2 (0.753 for males, 0.739 for females) values; however, the differences of the values derived from other criteria were minute. In addition, the symmetry (within the same jaw) and asymmetry (between the upper and lower jaws) of third molar development, which was confirmed in previous Korean studies, was observed only in the Demirjian and Liversidge criteria. Based on the results, we can conclude that all four tested criteria are suitable for age estimation in Koreans. However, the Demirjian and Liversidge criteria can be recommended from the perspective of accurate reflection of the developmental patterns. Further research is necessary to determine whether the results of this study are consistently observed in other populations.

13.
Sci Rep ; 13(1): 726, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36639726

RESUMEN

Teeth are known to be the most accurate age indicators of human body and are frequently applied in forensic age estimation. We aimed to validate data mining-based dental age estimation, by comparing the accuracy of the estimation and classification performance of 18-year thresholds with conventional methods and with data mining-based age estimation. A total of 2657 panoramic radiographs were collected from Koreans and Japanese populations aged 15 to 23 years. They were subdivided into a training and internal test set of 900 radiographs each from Koreans, and an external test set of 857 radiographs from Japanese. We compared the accuracy and classification performance of the test sets from conventional methods with those from the data mining models. The accuracy of the conventional method with the internal test set was slightly higher than that of the data mining models, with a slight difference (mean absolute error < 0.21 years, root mean square error < 0.24 years). The classification performance of the 18-year threshold was also similar between the conventional method and the data mining models. Thus, conventional methods can be replaced by data mining models in forensic age estimation using second and third molar maturity of Korean juveniles and young adults.


Asunto(s)
Determinación de la Edad por los Dientes , Humanos , Adulto Joven , Determinación de la Edad por los Dientes/métodos , Pueblo Asiatico , Minería de Datos , Tercer Molar , República de Corea , Japón
14.
PLoS One ; 17(7): e0271247, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35802665

RESUMEN

This study aimed to validate Lee's age estimation method and assess the 18-year threshold in Korean and Japanese populations. We evaluated the maxillary and mandibular second (M2) and third molars (M3) in 2657 orthopantomograms of the Korean and Japanese populations aged 15-23 years (19.47±2.62 years for Koreans, 19.31±2.60 years for Japanese), using Demirjian's criteria. Dental age was estimated, and correlations between chronological and dental ages were analyzed. Classification performance was calculated based on the 18-year threshold. The relationship between developmental stage and chronologic age was analyzed using multiple linear regression. Our results revealed that Lee's method was appropriate for estimation in the Korean population. When the Lee's method was applied to the Japanese population, a lower value of correlation coefficients between estimated and chronological age, and lower specificity were observed. Population differences were observed predominantly in the stages of root development (stages F and G) of M2s and M3s in both jaws and more frequently in females than in males. In the multiple linear regression between developmental stage and chronological age, lower values of adjusted r2 were observed in the Japanese population than in the Koreans. In conclusion, the Lee's method derived from the Korean population data might be unsuitable for Japanese juveniles and adolescents. To support the findings of this study, future studies with samples from multiple institutions should be conducted. Future studies with larger sample sizes are also warranted to improve the accuracy of dental age estimation and confirm the developmental pattern of teeth in the Japanese population.


Asunto(s)
Determinación de la Edad por los Dientes , Adolescente , Determinación de la Edad por los Dientes/métodos , Femenino , Odontología Forense/métodos , Humanos , Japón , Masculino , Tercer Molar/diagnóstico por imagen , Radiografía Panorámica , República de Corea
15.
Nat Commun ; 13(1): 3171, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35676247

RESUMEN

To date, the search for active, selective, and stable electrocatalysts for the oxygen evolution reaction (OER) has not ceased and a detailed atomic-level design of the OER catalyst remains an outstanding (if not, compelling) problem. Considerable studies on different surfaces and polymorphs of iridium oxides (with varying stoichiometries and dopants) have emerged over the years, showing much higher OER activity than the conventionally reported rutile-type IrO2. Here, we have considered different metastable nanoporous and amorphous iridium oxides of different chemical stoichiometries. Using first-principles electronic structure calculations, we investigate the (electro)chemical stability, intercalation properties, and electronic structure of these iridium oxides. Using an empirical regression model between the Ir-O bond characteristics and the measured OER overpotentials, we demonstrate how activated Ir-O bonds (and the presence of more electrophilic oxygens) in these less understood polymorphs of iridium oxides can explain their superior OER performance observed in experiments.

16.
Leg Med (Tokyo) ; 58: 102094, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35688110

RESUMEN

This study aimed to examine the applicability of Willems' and Lee's methods in a Japanese population and to find the differences in teeth development between Japanese and Korean children by comparing the accuracy of their estimated age using the two methods. The developmental status of the lower left permanent teeth in 1,475 orthopantomograms of Japanese children were evaluated based on Demirjian's criteria, and the ages were estimated using Willems' and Lee's methods. The errors in estimated ages were calculated and compared with equivalent Korean population data. The accuracy of both methods for estimating the age of the Japanese population was similar to that in the Korean population except for that of Lee's method used in Japanese males. The results showed that there might be differences in teeth development between the Japanese and Korean boys. To increase the accuracy of the dental age estimation, the method that is derived from their own population data should be applied in forensic practice.


Asunto(s)
Determinación de la Edad por los Dientes , Diente , Determinación de la Edad por los Dientes/métodos , Niño , Estudios Transversales , Humanos , Japón , Masculino , Radiografía Panorámica , República de Corea , Diente/diagnóstico por imagen
17.
Int Neurourol J ; 26(1): 26-30, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35368183

RESUMEN

PURPOSE: To develop a rat model of bladder calculi in the neurogenic bladder following spinal cord injury (SCI) and assess bacterial communities within the biofilm of bladder calculi using denaturing gradient gel electrophoresis (DGGE). METHODS: The silk tied to a small segment of the Teflon IV catheter was implanted through the urethra into the bladder of rats with SCI induced by T9 laminectomy. After 6 months, the rats were sacrificed and their bladder calculi were collected by opening the bladders through the low-midline incision. Genomic DNA was extracted from the biofilm of bladder calculi followed by DGGE to obtain bacterial DNA. The DNA sequences were compared and analyzed using BLAST (Basic Local Alignment Search Tool) to identify bacteria. RESULTS: After placing silk nidus in the bladder for 6 months, all 6 rats developed bladder calculi. According to DGGE analysis, Pseudomonas aeruginosa was the most dominant strain, while Clostridium sp. and Lactobacillus sp. were relatively dominant strains within the biofilm of bladder calculi in the rats with SCI. CONCLUSION: DGGE analysis showed various microorganisms in the biofilm of calculi arising from a neurogenic bladder rat model. This research design can be the basis for clinical studies and may be applied to calculi in patients with neurogenic bladder following SCI.

18.
Sci Total Environ ; 813: 152565, 2022 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-34953844

RESUMEN

Classically, ecologists have considered that biota becomes more integrated and interdependent with ecosystem development in primary successional environments. However, recent work on soil microbial communities suggests that there may in fact be no change in network integration over successional time series. Here, we performed a test of this principle by identifying network-level topological features of the soil microbial co-occurrence networks in the primary successional foreland environment of the retreating high-Arctic glacier of Midtre Lovénbreen, Svalbard. Soil was sampled at sites along the foreland of inferred ages 10-90 years since deglaciation. DNA was extracted and amplicon sequenced for 16 s rRNA genes for bacteria and ITS1 region for fungi. Despite the chronologically-related soil pH decline and organic C/N accumulation, analysis on network-level topological features showed network integration did not change with inferred chronological ages, whereas network integration declined with decreasing pH and increasing total organic carbon (TOC) - both factors that can be viewed as an indicator of soil development. We also found that bacteria played a greater role in the network structure than fungi, with all keystone species in the microbial co-occurrence network being bacteria species. Both number and relative abundance of the keystone species were significantly higher when soil pH increased or TOC decreased. It appears that in the more extreme and less productive conditions of early primary succession, integration between members of soil biota into consortia may play a greater role in niche adaptation and survival. Our finding also emphasizes that ecosystem development is not simply a product of time but is influenced by locally heterogeneous factors.


Asunto(s)
Cubierta de Hielo , Suelo , Ecosistema , Consorcios Microbianos , Microbiología del Suelo
19.
Artículo en Inglés | MEDLINE | ID: mdl-34590995

RESUMEN

A Gram-stain-negative, aerobic, motile by gliding, rod-shaped and pink-coloured bacterium, designated strain SW-16T, was isolated from the sediment of small stream in the Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SW-16T formed a lineage within the genus Pedobacter of the family Sphingobacteriaceae. Phylogenetic analysis also showed that strain SW-16T was most closely related to Pedobacter soli 15-51T (98.0% 16S rRNA gene sequence similarity), Pedobacter humicola R135T (97.5%), Pedobacter suwonensis 15-52T (97.4%), Pedobacter sandarakinus DS-27T (97.0%) and Pedobacter kyungheensis THG-T17T (97.0%). Growth was observed at 10-37 °C (optimum at 30 °C), pH 6-8 (optimum at pH 7) and with 0-2.0 % NaCl (optimum at 0%). The major fatty acids of the bacterial strain were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (iso-C15 : 0 2-OH and/or C16 : 1 ω7c). The predominant respiratory quinone was menaquinone-7 and the major polar lipids were phosphatidylethanolamine, two unidentified amino lipids, one unidentified phospholipid and three unidentified lipids. The genome size of strain SW-16T was 5.8 Mbp and the G+C content was 38.5 mol%. Based on the results of phenotypic, genomic and phylogenetic analyses, strain SW-16T represents a novel species of the genus Pedobacter, for which the name Pedobacter riviphilus sp. nov. is proposed. The type strain is SW-16T (=KEMB 1602-396T=KCTC 82079T=JCM 34181T).


Asunto(s)
Pedobacter , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Pedobacter/genética , Filogenia , ARN Ribosómico 16S/genética , Ríos , Análisis de Secuencia de ADN , Microbiología del Suelo , Vitamina K 2
20.
Artículo en Inglés | MEDLINE | ID: mdl-33847556

RESUMEN

A novel bacterial strain, EJ-4T, isolated from stream water collected at Seo-ho in Suwon, Republic of Korea, was characterized based on a polyphasic taxonomic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain EJ-4T belonged to the genus Comamonas. The isolate is Gram-stain-negative, non-motile, aerobic, rod-shaped and forms pale yellow colonies on trypticase soy agar. The optimal growth of this strain was observed aerobically at 30 °C, pH 7 and 0.5 % NaCl. The major fatty acids were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 39.7 %) and C16 : 0 (32.0 %). The G+C content of strain EJ-4T was 58.4mol %. The average nucleotide identity and digital DNA-DNA hybridization values between strain EJ-4T and Comamoas testosteroni were 91.8 and 31.2 %, respectively. The major polar lipids detected in the isolate were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant isoprenoid quinone was ubiquinone-8. Based on the results of polyphasic taxonomic analysis of strain EJ-4T, we describe a novel species of the genus Comamonas, for which the name Comamonas suwonensis sp. nov. has been proposed, with EJ-4T (=KCTC 82074T=JCM 34179T=KEMB 1602-279T) as the type strain.


Asunto(s)
Comamonas/clasificación , Filogenia , Ríos/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Comamonas/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Ubiquinona/química
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