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1.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298428

RESUMO

Brain structural morphology varies over the aging trajectory, and the prediction of a person's age using brain morphological features can help the detection of an abnormal aging process. Neuroimaging-based brain age is widely used to quantify an individual's brain health as deviation from a normative brain aging trajectory. Machine learning approaches are expanding the potential for accurate brain age prediction but are challenging due to the great variety of machine learning algorithms. Here, we aimed to compare the performance of the machine learning models used to estimate brain age using brain morphological measures derived from structural magnetic resonance imaging scans. We evaluated 27 machine learning models, applied to three independent datasets from the Human Connectome Project (HCP, n = 1113, age range 22-37), the Cambridge Centre for Ageing and Neuroscience (Cam-CAN, n = 601, age range 18-88), and the Information eXtraction from Images (IXI, n = 567, age range 19-86). Performance was assessed within each sample using cross-validation and an unseen test set. The models achieved mean absolute errors of 2.75-3.12, 7.08-10.50, and 8.04-9.86 years, as well as Pearson's correlation coefficients of 0.11-0.42, 0.64-0.85, and 0.63-0.79 between predicted brain age and chronological age for the HCP, Cam-CAN, and IXI samples, respectively. We found a substantial difference in performance between models trained on the same data type, indicating that the choice of model yields considerable variation in brain-predicted age. Furthermore, in three datasets, regularized linear regression algorithms achieved similar performance to nonlinear and ensemble algorithms. Our results suggest that regularized linear algorithms are as effective as nonlinear and ensemble algorithms for brain age prediction, while significantly reducing computational costs. Our findings can serve as a starting point and quantitative reference for future efforts at improving brain age prediction using machine learning models applied to brain morphometric data.


Assuntos
Conectoma , Aprendizado de Máquina , Humanos , Adulto Jovem , Adulto , Adolescente , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Conectoma/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos
2.
3 Biotech ; 12(11): 283, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36276452

RESUMO

Recombinant Escherichia coli and Bacillus subtilis strains were engineered by simultaneous chemical and ultraviolet-induced random mutagenesis to enhance bio-alcohol production. Our study investigated the bio-alcohol production of six variants of E. coli (EM1-6) and B. subtilis mutants (BM1-6). The induced mutation in the EM variants increased isobutanol (C4 alcohol) production most effectively, whereas pH adjustment and additional l-valine feeding increased isobutanol production by the BM variants. In contrast, pH adjustment or l-valine addition negatively affected isobutanol production by the EM variants. The highest titer of 5.07 g/L of isobutanol from a 40 g/L yeast extract medium (YEM) was achieved by the EM1 variant, whereas 0.57 g/L of isobutanol from YEM supplemented with 5 g/L of l-valine was obtained from the BM5 variant. These results can be applied in further research on engineering production hosts and improving production titers to utilize heterogenous bioresources in the future.

3.
J Ginseng Res ; 46(3): 367-375, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35600782

RESUMO

Background: Short-term hydroponic-cultured ginseng (sHCG), which is 1-year-old ginseng seedlings cultivated for 4 weeks in a hydroponic system, is a functional food item with several biological effects. However, the optimal extraction conditions for sHCG, and the bioactivity of its extracts, have not been evaluated. Methods: Chlorogenic acid (CGA) and ginsenoside contents were evaluated in sHCG, white ginseng (WG), and red ginseng (RG) using high-performance liquid chromatography. Response surface methodology (RSM) was used to optimize the extraction conditions (temperature and ethanol concentration) to maximize the yield of dry matter, CGA, and four ginsenosides (Re, Rg1, Rb1, and Rd) from sHCG. The optimal extraction conditions were applied to pilot-scale production of sHCG extracts. The expression levels of tumor necrosis factor (TNF)-α/interferon (IFN)-γ-induced thymic and activation-regulated chemokines (TARC/CCL17) were measured after treatment with sHCG, WG, and RG extracts, and the effects of their bioactive compounds (CGA and four ginsenosides) on human skin keratinocytes (HaCaTs) were evaluated. Results: CGA and four ginsenosides, which are bioactive compounds of sHCG, significantly inhibited TNF-α/IFN-γ-induced TARC/CCL17 expression. The optimal sHCG extraction conditions predicted by the RSM models were 80 °C and 60% ethanol (v/v). The sHCG extracts produced at the pilot scale under optimal conditions greatly alleviated TNF-α/IFN-γ-induced TARC/CCL17 production compared with WG and RG extracts. Conclusions: Pesticide-free sHCG extracts, which contain high levels of CGA and the ginsenosides Re, Rg1, Rb1, and Rd as bioactive compounds, may have therapeutic potential for atopic diseases.

4.
Crit Rev Biotechnol ; 41(6): 827-848, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33622141

RESUMO

Bacillus subtilis is regarded as a suitable host for biochemical production owing to its excellent growth and bioresource utilization characteristics. In addition, the distinct endogenous metabolic pathways and the suitability of the heterologous pathways have made B. subtilis a robust and promising host for producing biochemicals, such as: bioalcohols; bioorganic acids (lactic acids, α-ketoglutaric acid, and γ-aminobutyric acid); biopolymers (poly(γ-glutamic acid, polyhydroxyalkanoates (PHA), and polysaccharides and monosaccharides (N-acetylglucosamine, xylooligosaccharides, and hyaluronic acid)); and bioflocculants. Also for producing oligopeptides and functional peptides, owing to its efficient protein secretion system. Several metabolic and genetic engineering techniques, such as target gene overexpression and inactivation of bypass pathways, have led to the improvement in production titers and product selectivity. In this review article, recent progress in the utilization of robust B. subtilis-based host systems for biomass conversion and biochemical production has been highlighted, and the prospects of such host systems are suggested.


Assuntos
Bacillus subtilis , Redes e Vias Metabólicas , Bacillus subtilis/genética , Biomassa , Engenharia Genética , Engenharia Metabólica , Peptídeos
5.
Food Sci Biotechnol ; 29(7): 1007-1012, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32577317

RESUMO

Panax ginseng CA Meyer has a variety of biological effects, including antioxidant and antidiabetic activities. Ginseng requires long-term cultivation, but this can be shortened using hydroponic systems to facilitate the commercial development of ginseng as a functional food. However, the characteristics of short-term-cultured (< 30 days) hydroponic ginseng (sHCG) are unclear. We investigated the characteristics of 21-day-cultured sHCG compared 5-year-old normally cultured ginseng. The free radical-scavenging activity and total ginsenoside and phenolic contents were significantly higher in sHCG than in normally cultured ginseng. Fifteen ginsenosides were detected in sHCG, and the concentrations of most were higher in shoots than roots. These findings suggest that 21-day-cultured sHCG, due to its enhanced antioxidant activity and higher concentrations of total phenolics and ginsenosides (including Rd and Re), has potential as a functional food.

6.
Pain Physician ; 22(5): E417-E424, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31561653

RESUMO

BACKGROUND: Sympathetic block is commonly performed in clinical practice for management of intractable pain conditions. However, stellate ganglion block (SGB) alone often does not achieve sufficient sympatholysis of the upper extremity. The paravertebral space continues up to the cervical sympathetic chain and includes the stellate ganglion. We compared the sympatholytic and analgesic effect of paravertebral block performed at the T2 level (T2 PVB) with that of SGB in patients with complex regional pain syndrome (CRPS) of the upper extremity. OBJECTIVES: The aim of this study was to compare the sympatholytic property of T2 PVB with that of the conventional SGB in patients with CRPS of the upper extremity. STUDY DESIGN: Prospective, randomized cross-over trial. SETTING: University hospital pain center in Korea. METHODS: Fifteen patients with upper extremity CRPS were randomly assigned to 1 of 2 intervention methods (SGB or T2 PVB). After effects of the first block receded, the patients were crossed over to the second procedure. A difference in temperature increase between the treated side and the opposite side (DeltaT) DeltaT greater than or equal to1.5°C was considered as a successful primary outcome. Rate of successful primary outcome, degree of pain reduction, duration of effect, and patient satisfaction scores were compared between the 2 intervention methods. RESULTS: Rate of successful primary outcome (DeltaT greater than or equal to 1.5°C) was significantly higher in the T2 PVB cases than in the SGB cases (80.0% vs. 20.0%; P = 0.003). Numeric Rating Scale scores after the procedure were significantly lower in the T2 PVB group. Patient satisfaction scores were significantly higher, and the duration of the block was significantly longer in the T2 PVB cases than in the SGB cases. LIMITATIONS: The relatively small sample size from a single center, and the lack of standardization of the injected volume of T2 PVB and SGB were limitations. CONCLUSIONS: T2 PVB showed superior sympatholytic effect than SGB; other clinical outcomes were also better with T2 PVB than with SGB. T2 PVB can be a useful option for producing sympatholytic and analgesic effect in patients with CRPS of the upper extremity. KEY WORDS: Sympathetic block, Complex Regional Pain Syndrome, paravertebral block, stellate ganglion block.


Assuntos
Bloqueio Nervoso Autônomo/métodos , Adulto , Síndromes da Dor Regional Complexa , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição Aleatória , República da Coreia , Gânglio Estrelado/efeitos dos fármacos , Sistema Nervoso Simpático , Extremidade Superior
7.
Front Mol Neurosci ; 12: 145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249508

RESUMO

Nav1.2, a voltage-gated sodium channel subunit encoded by the Scn2a gene, has been implicated in various brain disorders, including epilepsy, autism spectrum disorder, intellectual disability, and schizophrenia. Nav1.2 is known to regulate the generation of action potentials in the axon initial segment and their propagation along axonal pathways. Nav1.2 also regulates synaptic integration and plasticity by promoting back-propagation of action potentials to dendrites, but whether Nav1.2 deletion in mice affects neuronal excitability, synaptic transmission, synaptic plasticity, and/or disease-related animal behaviors remains largely unclear. Here, we report that mice heterozygous for the Scn2a gene (Scn2a +/- mice) show decreased neuronal excitability and suppressed excitatory synaptic transmission in the presence of network activity in the hippocampus. In addition, Scn2a +/- mice show suppressed hippocampal long-term potentiation (LTP) in association with impaired spatial learning and memory, but show largely normal locomotor activity, anxiety-like behavior, social interaction, repetitive behavior, and whole-brain excitation. These results suggest that Nav1.2 regulates hippocampal neuronal excitability, excitatory synaptic drive, LTP, and spatial learning and memory in mice.

8.
BMC Oral Health ; 19(1): 67, 2019 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036007

RESUMO

BACKGROUND: Tuberculosis (TB) is a serious infectious disease with considerable fatality, typically affecting the pulmonary system and, rarely, other body organs including the oral cavity. Due to the rarity of oral TB, it is frequently overlooked in differential diagnosis of oral lesions. Despite a declining trend in TB incidence in recent years, it is still a major public health problem with high contagiousness, thereby requiring the early diagnosis and prompt treatment. CASE PRESENTATION: A 57-year-old male patient presented with chief complaint of painful ulcer on tip of his tongue. He reported that the ulcer developed without any remarkable event such as mechanical trauma, vesicle formation or systemic illness. His past medical history revealed the TB over 40 years ago, which had reportedly healed after pharmacological treatments. As the ulceration persisted after topical steroid application and careful education about avoiding possible mechanical stimuli, biopsy was performed and histological finding showed typical findings of oral tuberculosis including intense granulomatous inflammatory features with small red rods of mycobacterial organisms as well as epithelioid cells and Langhans giant cells. After suitable antituberculosis treatments, oral tuberculosis ulcer was almost completely healed. We present a case of oral TB affecting tip of the tongue in a patient with a history of pulmonary TB and emphasize the understanding of intraoral manifestations for early diagnosis and prompt treatment of TB. CONCLUSIONS: The present case represented the importance of understanding oral tuberculosis manifestations for dental clinicians who might be frequently the first health care professionals to encounter various oral lesions.


Assuntos
Úlceras Orais/patologia , Doenças da Língua/patologia , Tuberculose Bucal/patologia , Tuberculose , Humanos , Masculino , Pessoa de Meia-Idade
9.
Med Hypotheses ; 121: 70-73, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30396497

RESUMO

The aim of this study is to develop an alternative way to locate the sacral hiatus for blind caudal block from the anthropometrical data measured on 3D pelvic CT. The intersection of the line connecting two sacral cornua and the midline is considered the ideal point (IP) for caudal block. The mean length from the coccyx tip to the IP was measured using 3D pelvic CT images in 30 men and 30 women and was 6.5 cm and 6.0 cm, respectively. For the conventional method group, we used the conventional equilateral triangle method to find the sacral hiatus, which was named conventional method group needling point (CNP). For the experimental method group, the point 6.5 cm or 6.0 cm (mean length from the coccyx tip to the IP) away from the coccyx tip was called the experimental method group needling point (ENP). Drawing the three points of the IP, CNP, and ENP on the same patient's 3D pelvic CT, we compared the distance from the IP to the CNP with the distance from the IP to the ENP. We propose that the experimental method is comparable to the conventional method in locating the sacral hiatus, which is crucial for a successful caudal block procedure. Anthropometric measurements and virtual comparative test between two methods were done on the 3D pelvis CT. In men, the distance from the CNP to the IP was 0.8 ±â€¯0.5 cm in the conventional method group, while the distance from the ENP to the IP was 0.5 ±â€¯0.4 cm in the experimental method group (p < 0.05). In women, the same distances were 1.5 ±â€¯0.8 cm and 0.7 ±â€¯0.3 cm, respectively (p < 0.05). In conclusion, finding a point of 6.5 cm from the coccyx tip in men and 6.0 cm in women could be an alternative way to find the sacral hiatus for blind caudal block.


Assuntos
Antropometria , Imageamento Tridimensional/métodos , Bloqueio Nervoso/métodos , Sacro/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Anestesia Epidural , Cóccix/patologia , Feminino , Humanos , Modelos Lineares , Masculino , Agulhas , Pelve/diagnóstico por imagem , Estudos Retrospectivos
10.
Antonie Van Leeuwenhoek ; 111(12): 2393-2402, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30022265

RESUMO

A Gram-stain negative, non-motile, rod-shaped bacterial strain, designated 2-56T, was isolated from water and characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 2-56T belongs to the family Flavobacteriaceae in the phylum Bacteroidetes and is closely related to Flavobacterium paronense KNUS1T (98.4%) and Flavobacterium collinsense 4-T-2T (96.7%). The G + C content of the genomic DNA of strain 2-56T was 33.4 mol%. The isolate contained MK-6 as the predominant respiratory quinone, and iso-C15:1 G (15.9%), iso-C15:0 (15.8%), iso-C17:0 3-OH (10.7%), and iso-C15:0 3-OH (9.6%) were the major fatty acids. The major polar lipids were phosphatidylethanolamine and an unidentified lipid. The phenotypic and chemotaxonomic data support the affiliation of strain 2-56T with the genus Flavobacterium. However, the DNA-DNA relatedness between the isolate and F. paronense and F. collinsense were 35.7 and 21.5%, respectively, clearly showing that strain 2-56T is not related to them at the species level. Strain 2-56T could be clearly differentiated from its close neighbours on the basis of its phenotypic, genotypic and chemotaxonomic features. Therefore, strain 2-56T represents a novel species of the genus Flavobacterium, for which the name Flavobacterium knui sp. nov. is proposed. The type strain is 2-56T (= KCTC 62061T = JCM 32247T).


Assuntos
DNA Bacteriano/genética , Flavobacterium/classificação , Filogenia , RNA Ribossômico 16S/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/biossíntese , Flavobacterium/química , Flavobacterium/genética , Flavobacterium/isolamento & purificação , Genótipo , Fenótipo , Fosfatidiletanolaminas/biossíntese , República da Coreia , Microbiologia da Água
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