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1.
Hum Mol Genet ; 32(3): 417-430, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35997776

RESUMO

Mucopolysaccharidosis type IIIB (MPS IIIB) is an autosomal recessive lysosomal storage disease caused by mutations in the gene that encodes the protein N-acetyl-glucosaminidase (NAGLU). Defective NAGLU activity results in aberrant retention of heparan sulfate within lysosomes leading to progressive central nervous system (CNS) degeneration. Intravenous treatment options are limited by the need to overcome the blood-brain barrier and gain successful entry into the CNS. Additionally, we have demonstrated that AAV8 provides a broader transduction area in the MPS IIIB mouse brain compared with AAV5, 9 or rh10. A triple-capsid mutant (tcm) modification of AAV8 further enhanced GFP reporter expression and distribution. Using the MPS IIIB mouse model, we performed a study using either intracranial six site or intracisterna magna injection of AAVtcm8-codon-optimized (co)-NAGLU using untreated MPS IIIB mice as controls to assess disease correction. Disease correction was evaluated based on enzyme activity, heparan sulfate storage levels, CNS lysosomal signal intensity, coordination, activity level, hearing and survival. Both histologic and enzymatic assessments show that each injection method results in supranormal levels of NAGLU expression in the brain. In this study, we have shown correction of lifespan and auditory deficits, increased CNS NAGLU activity and reduced lysosomal storage levels of heparan sulfate following AAVtcm8-coNAGLU administration and partial correction of NAGLU activity in several peripheral organs in the murine model of MPS IIIB.


Assuntos
Mucopolissacaridose III , Animais , Camundongos , Mucopolissacaridose III/genética , Mucopolissacaridose III/terapia , Mucopolissacaridose III/metabolismo , Capsídeo/metabolismo , Acetilglucosaminidase/genética , Acetilglucosaminidase/metabolismo , Heparitina Sulfato/metabolismo
2.
Curr Issues Mol Biol ; 45(12): 10159-10178, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38132480

RESUMO

The process of skin aging is currently recognized as a disease, and extracellular vesicles (EVs) are being used to care for it. While various EVs are present in the market, there is a growing need for research on improving skin conditions through microbial and plant-derived EVs. Edelweiss is a medicinal plant and is currently an endangered species. Callus culture is a method used to protect rare medicinal plants, and recently, research on EVs using callus culture has been underway. In this study, the researchers used LED light to increase the productivity of Edelweiss EVs and confirmed that productivity was enhanced by LED exposure. Additionally, improvements in skin anti-aging indicators were observed. Notably, M-LED significantly elevated callus fresh and dry weight, with a DW/FW ratio of 4.11%, indicating enhanced proliferation. Furthermore, M-LED boosted secondary metabolite production, including a 20% increase in total flavonoids and phenolics. The study explores the influence of M-LED on EV production, revealing a 2.6-fold increase in concentration compared to darkness. This effect is consistent across different plant species (Centella asiatica, Panax ginseng), demonstrating the universality of the phenomenon. M-LED-treated EVs exhibit a concentration-dependent inhibition of reactive oxygen species (ROS) production, surpassing dark-cultured EVs. Extracellular melanin content analysis reveals M-LED-cultured EVs' efficacy in reducing melanin production. Additionally, the expression of key skin proteins (FLG, AQP3, COL1) is significantly higher in fibroblasts treated with M-LED-cultured EVs. These results are expected to provide valuable insights into research on improving the productivity of plant-derived EVs and enhancing skin treatment using plant-derived EVs.

3.
J Korean Med Sci ; 37(7): e58, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35191234

RESUMO

Guillain-Barre syndrome (GBS) is an immune-mediated acute polyradiculoneuropathy and commonly occurs after a preceding infection or immunization sequalae. Following the severe acute respiratory syndrome-coronavirus-2 virus pandemic with co-introduction of massive vaccinations, several GBS cases associated with coronavirus disease 2019 (COVID-19) infection per se or after vaccination for COVID-19 were reported internationally. Herein, we report two cases of Korean GBS presenting with tetraplegia after two different COVID-19 vaccinations (42-year old man by AstraZeneca and 48-year woman by Pfizer vaccines) within four weeks after vaccination. The patients were diagnosed with clinical examination, serial electromyography, and compatible laboratory results and improved after comprehensive rehabilitative treatment and intravenous immunoglobulin therapy. Furthermore, we performed an electrodiagnostic follow-up study of each case to examine their unique characteristics.


Assuntos
Vacina BNT162/efeitos adversos , ChAdOx1 nCoV-19/efeitos adversos , Síndrome de Guillain-Barré/patologia , Quadriplegia/patologia , Vacinação/efeitos adversos , Adulto , Vacina BNT162/imunologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19/imunologia , Eletromiografia , Feminino , Síndrome de Guillain-Barré/reabilitação , Síndrome de Guillain-Barré/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Quadriplegia/reabilitação , Quadriplegia/terapia , SARS-CoV-2/imunologia
4.
Dysphagia ; 37(6): 1748-1756, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35304623

RESUMO

Dysphagia is one of the main serious issues for amyotrophic lateral sclerosis (ALS) patients because of causing malnutrition and aspiration pneumonia. Early detection and management of dysphagia are essential for the long-term survival. In this study, videofluoroscopic swallowing study (VFSS) results of bulbar and spinal onset ALS patients were compared. VFSS results and revised ALS Functional Rating Scale (ALSFRS-R) score were also analyzed to assess the correlation between dysphagia and functional status of patients. ALS patients with swallowing difficulties who underwent VFSS were recruited retrospectively. Two oral, seven pharyngeal, and two esophageal components of VFSS were evaluated. An ALSRFRS-R bulbar subtype score < 9 was used to divide the groups with severe bulbar symptoms. Total 109 Korean ALS patients (39 bulbar vs 70 spinal) were included. Bulbar ALS patients exhibited a significantly longer oral transit time (OTT) then spinal ALS patients, especially in severe bulbar patients with low ALSRFRS-R bulbar subscale. In bulbar ALS patients, penetration (thick liquid), aspiration, OTT, and Penetration-Aspiration Scale (PAS) were significantly correlated with ALSFRS-R bulbar subscale score. However, in spinal ALS patients, only OTT (thin liquid) and aspiration (thick liquid) were significantly correlated with ALSFRS-R bulbar subscale score. Bulbar ALS patients demonstrated significantly longer OTT than spinal ALS patients, and ALSFRS-R bulbar subscale score also correlated well with bulbar ALS patients. Therefore, high vigilance and aggressive treatment for dysphagia especially in bulbar ALS patients rather than spinal ALS patients are mandatory.


Assuntos
Esclerose Lateral Amiotrófica , Transtornos de Deglutição , Humanos , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Esclerose Lateral Amiotrófica/complicações , Estudos Retrospectivos , Índice de Gravidade de Doença , República da Coreia
5.
Clin Gastroenterol Hepatol ; 19(12): 2577-2586.e6, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32882425

RESUMO

BACKGROUND & AIMS: Long-term outcomes of constipation have not been evaluated fully. We investigated the incidence of Parkinson's disease, constipation-related surgery, and colorectal cancer (CRC) in patients with constipation and slow-transit constipation (STC), followed up for up to 20 years. METHODS: We collected data from 2165 patients (33.1% men; median patient age, 54 y; median symptom duration, 5.0 y) with a diagnosis of constipation (based on Rome II criteria) who underwent an anorectal function test and a colonic transit time study, from 2000 through 2010, at a tertiary university hospital in Seoul, South Korea. The presence of STC was determined from colonic transit time. We used the Kaplan-Meier method to analyze and compare cumulative probabilities of a new diagnosis of Parkinson's disease or CRC according to the presence of STC. The patients were followed up until the end of 2019. RESULTS: During a median follow-up period of 4.7 years (interquartile range, 0.7-8.3 y), 10 patients underwent constipation-related surgery. The cumulative probabilities of constipation-related surgery were 0.7% at 5 years and 0.8% at 10 years after a diagnosis of constipation. Twenty-nine patients (1.3%) developed Parkinson's disease; the cumulative probabilities were 0.4% at 1 year, 1.0% at 5 years, and 2.6% at 10 years after a diagnosis of constipation. At 10 years, 1.3% of patients with STC required constipation-related surgery and 3.5% of patients with STC developed Parkinson's disease; in contrast, none of the patients without STC required constipation-related surgery (P = .003), and 1.5% developed Parkinson's disease (P = .019). In multivariate analysis, patient age of 65 years or older at the diagnosis of constipation (hazard ratio, 4.834; 95% CI, 2.088-11.190) and the presence of STC (hazard ratio, 2.477; 95% CI, 1.046-5.866) were associated independently with the development of Parkinson's disease. Only 5 patients had a new diagnosis of CRC during the follow-up period. The risk of CRC did not differ significantly between patients with vs without STC (P = .575). CONCLUSIONS: In a long-term follow-up study of patients with constipation in Korea, most patients had no severe complications. However, patients older than age 65 years with a new diagnosis of STC might be considered for Parkinson's disease screening.


Assuntos
Neoplasias Colorretais , Doença de Parkinson , Idoso , Colo , Neoplasias Colorretais/complicações , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Constipação Intestinal/epidemiologia , Constipação Intestinal/etiologia , Feminino , Seguimentos , Trânsito Gastrointestinal , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia
6.
BMC Nephrol ; 22(1): 86, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691638

RESUMO

BACKGROUND: Thrombotic microangiopathy (TMA), a rare but serious complication of systemic lupus erythematosus (SLE), is associated with poor outcomes to conventional immunosuppressive therapy. Recently, eculizumab, a humanised monoclonal antibody that blocks the complement factor 5, has been known to effectively treat atypical haemolytic uremic syndrome (aHUS). Here, we report a case of aHUS co-existing with lupus nephritis that was successfully treated with eculizumab. CASE PRESENTATION: A 23-year-old man presented with abdominal pain and diarrhoea. Initial laboratory tests have shown thrombocytopaenia, microangiopathic haemolytic anaemia, and acute kidney injury. Immunologic tests were consistent with SLE. Kidney biopsy have revealed lupus nephritis class IV-G with TMA. Genetic analysis have shown complement C3 gene mutations, which hints the co-existence of lupus nephritis with aHUS, a form of complement-mediated TMA. Although initial treatment with haemodialysis, plasma exchange, and conventional immunosuppressive therapy (steroid and cyclophosphamide) did not appreciably improve kidney function and thrombocytopaenia, the patient was able to respond to eculizumab therapy. CONCLUSIONS: Due to the similar features of TMA and SLE, clinical suspicion of aHUS in patients with lupus nephritis is important for early diagnosis and prompt management. Timely administration of eculizumab should be considered as a treatment option for aHUS in lupus nephritis patients to yield optimal therapeutic outcomes.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Síndrome Hemolítico-Urêmica Atípica/tratamento farmacológico , Inativadores do Complemento/uso terapêutico , Mutação , Síndrome Hemolítico-Urêmica Atípica/complicações , Síndrome Hemolítico-Urêmica Atípica/genética , Complemento C3/genética , Humanos , Nefrite Lúpica/complicações , Masculino , Adulto Jovem
7.
J Korean Med Sci ; 36(12): e80, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33783145

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a serious clinical condition that impacts a patient's physical, psychological, and socio-economic status. The aim of this pilot study was to evaluate the effects of training with a newly developed powered wearable exoskeleton (Hyundai Medical Exoskeleton [H-MEX]) on functional mobility, physiological health, and quality of life in non-ambulatory SCI patients. METHODS: Participants received 60 minutes of walking training with a powered exoskeleton 3 times per week for 10 weeks (total 30 sessions). The 6-minute walking test (6MWT) and timed-up-and-go test (TUGT) were performed to assess ambulatory function. The physiological outcomes of interest after exoskeleton-assisted walking training were spasticity, pulmonary function, bone mineral density, colon transit time, and serum inflammatory markers. Effects of walking training on subjective outcomes were estimated by the Korean version of the Falls Efficacy Scale-International and the 36-Item Short-Form Health Survey version 2. RESULTS: Ten participants finished 30 sessions of training and could ambulate independently. No severe adverse events were reported during the study. After training, the mean distance walked in the 6MWT (49.13 m) was significantly enhanced compared with baseline (20.65 m). The results of the TUGT also indicated a statistically significant improvement in the times required to stand up, walk 3 m and sit down. Although not statistically significant, clinically meaningful changes in some secondary physiological outcomes and/or quality of life were reported in some participants. CONCLUSION: In conclusion, this study demonstrated that the newly developed wearable exoskeleton, H-MEX is safe and feasible for non-ambulatory SCI patients, and may have potential to improve quality of life of patients by assisting bipedal ambulation. These results suggest that the H-MEX can be considered a beneficial device for chronic non-ambulatory SCI patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04055610.


Assuntos
Exoesqueleto Energizado , Qualidade de Vida , Traumatismos da Medula Espinal/psicologia , Adulto , Densidade Óssea , Proteína C-Reativa/análise , Feminino , Humanos , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular , Projetos Piloto , Estudos Prospectivos , Testes de Função Respiratória , Traumatismos da Medula Espinal/reabilitação , Estudos de Tempo e Movimento , Dispositivos Eletrônicos Vestíveis
8.
Chem Biodivers ; 18(10): e2100383, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34405949

RESUMO

Miscanthus sinensis var. purpurascens (MSP, flame grass) is found in Korea, Japan, and China, and its biological activities include anti-cancer, detoxifying, vasodilatory, antipyretic, and diuretic effects. However, no study has investigated the effects of MSP on skin-related biological activities. In this study, we explored the effects of the absolute extracted from the MSP flowers (MSPFAb) on skin wound healing- and whitening-related responses in keratinocytes or melanocytes. MSPFAb contained 6 components and induced the proliferation, migration, and syntheses of type I and IV collagens in keratinocytes. MSPFAb also increased the phosphorylations of serine/threonine-specific protein kinase, p38 mitogen-activated protein kinase, and extracellular signal-regulated kinase1/2 in keratinocytes. In addition, treatment with MSPFAb decreased serum-induced melanoma cell proliferation and inhibited tyrosinase activity and melanin contents in α-MSH-stimulated melanoma cells. Taken together, this study indicates MSPFAb may promote wound healing- and whitening-associated activities in dermal cells, and suggests that it has potential use as a wound healing and skin whitening agent.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flores/química , Extratos Vegetais/farmacologia , Poaceae/química , Pele/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células Tumorais Cultivadas
9.
Sensors (Basel) ; 21(15)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34372258

RESUMO

Exercise intensity of exoskeleton-assisted walking in patients with spinal cord injury (SCI) has been reported as moderate. However, the cardiorespiratory responses to long-term exoskeleton-assisted walking have not been sufficiently investigated. We investigated the cardiorespiratory responses to 10 weeks of exoskeleton-assisted walking training in patients with SCI. Chronic nonambulatory patients with SCI were recruited from an outpatient clinic. Walking training with an exoskeleton was conducted three times per week for 10 weeks. Oxygen consumption and heart rate (HR) were measured during a 6-min walking test at pre-, mid-, and post-training. Exercise intensity was determined according to the metabolic equivalent of tasks (METs) for SCI and HR relative to the HR reserve (%HRR). Walking efficiency was calculated as oxygen consumption divided by walking speed. The exercise intensity according to the METs (both peak and average) corresponded to moderate physical activity and did not change after training. The %HRR demonstrated a moderate (peak %HRR) and light (average %HRR) exercise intensity level, and the average %HRR significantly decreased at post-training compared with mid-training (31.6 ± 8.9% to 24.3 ± 7.3%, p = 0.013). Walking efficiency progressively improved after training. Walking with an exoskeleton for 10 weeks may affect the cardiorespiratory system in chronic patients with SCI.


Assuntos
Exoesqueleto Energizado , Traumatismos da Medula Espinal , Marcha , Humanos , Consumo de Oxigênio , Caminhada
10.
Int J Mol Sci ; 22(4)2021 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-33668636

RESUMO

Tomato is one of the major vegetable crops consumed worldwide. Tomato yellow leaf curl virus (TYLCV) and fungal Oidium sp. are devastating pathogens causing yellow leaf curl disease and powdery mildew. Such viral and fungal pathogens reduce tomato crop yields and cause substantial economic losses every year. Several commercial tomato varieties include Ty-5 (SlPelo) and Mildew resistance locus o 1 (SlMlo1) locus that carries the susceptibility (S-gene) factors for TYLCV and powdery mildew, respectively. The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) is a valuable genome editing tool to develop disease-resistant crop varieties. In this regard, targeting susceptibility factors encoded by the host plant genome instead of the viral genome is a promising approach to achieve pathogen resistance without the need for stable inheritance of CRISPR components. In this study, the CRISPR/Cas9 system was employed to target the SlPelo and SlMlo1 for trait introgression in elite tomato cultivar BN-86 to confer host-mediated immunity against pathogens. SlPelo-knockout lines were successfully generated, carrying the biallelic indel mutations. The pathogen resistance assays in SlPelo mutant lines confirmed the suppressed accumulation of TYLCV and restricted the spread to non-inoculated plant parts. Generated knockout lines for the SlMlo1 showed complete resistance to powdery mildew fungus. Overall, our results demonstrate the efficiency of the CRISPR/Cas9 system to introduce targeted mutagenesis for the rapid development of pathogen-resistant varieties in tomato.


Assuntos
Begomovirus/metabolismo , Sistemas CRISPR-Cas , Resistência à Doença/genética , Edição de Genes , Doenças das Plantas , Plantas Geneticamente Modificadas , Solanum lycopersicum , Genoma de Planta , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/microbiologia , Solanum lycopersicum/virologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/microbiologia , Plantas Geneticamente Modificadas/virologia
11.
Molecules ; 26(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34684753

RESUMO

Angelica polymorpha Maxim. (APM) is used in traditional medicine to treat chronic gastritis, rheumatic pain, and duodenal bulbar ulcers. However, it is not known whether APM has epidermis-associated biological activities. Here, we investigated the effects of APM flower absolute (APMFAb) on responses associated with skin wound healing and whitening using epidermal cells. APMFAb was obtained by solvent extraction and its composition was analyzed by GC/MS. Water-soluble tetrazolium salt, 5-bromo-2'-deoxyuridine incorporation, Boyden chamber, sprouting, and enzyme-linked immunosorbent assays and immunoblotting were used to examine the effects of APMFAb on HaCaT keratinocytes and B16BL6 melanoma cells. APMFAb contained five compounds and induced keratinocyte migration, proliferation, and type IV collagen synthesis. APMFAb also induced the phosphorylations of ERK1/2, JNK, p38 mitogen-activated protein kinase, and AKT in keratinocytes. In addition, APMFAb decreased serum-induced B16BL6 cell proliferation and inhibited tyrosinase expression, melanin contents, and microphthalmia-associated transcription factor expression in α-melanocyte-stimulating hormone-stimulated B16BL6 cells. These findings demonstrate that APMFAb has beneficial effects on skin wound healing by promoting the proliferation, migration, and collagen synthesis of keratinocytes and on skin whitening by inhibiting melanin synthesis in melanoma cells. Therefore, we suggest that APMFAb has potential use as a wound healing and skin whitening agent.


Assuntos
Angelica/metabolismo , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Flores/metabolismo , Humanos , Queratinócitos/efeitos dos fármacos , Melaninas/biossíntese , Melaninas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo
12.
Korean J Physiol Pharmacol ; 25(5): 449-457, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34448462

RESUMO

The sleep-wake cycle is regulated by the alternating activity of sleep- and wake-promoting neurons. The dorsal raphe nucleus (DRN) secretes 5-hydroxytryptamine (5-HT, serotonin), promoting wakefulness. Melatonin secreted from the pineal gland also promotes wakefulness in rats. Our laboratory recently demonstrated that daily changes in nitric oxide (NO) production regulates a signaling pathway involving with-no-lysine kinase (WNK), Ste20-related proline alanine rich kinase (SPAK)/oxidative stress response kinase 1 (OSR1), and cation-chloride co-transporters (CCC) in rat DRN serotonergic neurons. This study was designed to investigate the effect of melatonin on NO-regulated WNK-SPAK/OSR1-CCC signaling in wake-inducing DRN neurons to elucidate the mechanism underlying melatonin's wake-promoting actions in rats. Ex vivo treatment of DRN slices with melatonin suppressed neuronal nitric oxide synthase (nNOS) expression and increased WNK4 expression without altering WNK1, 2, or 3. Melatonin increased phosphorylation of OSR1 and the expression of sodium-potassium-chloride co-transporter 1 (NKCC1), while potassium-chloride cotransporter 2 (KCC2) remained unchanged. Melatonin increased the expression of tryptophan hydroxylase 2 (TPH2, serotonin-synthesizing enzyme). The present study suggests that melatonin may promote its wakefulness by modulating NO-regulated WNK-SPAK/OSR1-KNCC1 signaling in rat DRN serotonergic neurons.

13.
Biochemistry ; 59(5): 682-693, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31899625

RESUMO

(1,3)-ß-d-Glucan synthase (GS) catalyzes formation of the linear (1,3)-ß-d-glucan in the fungal cell wall and is a target of clinically approved antifungal antibiotics. The catalytic subunit of GS, FKS protein, does not exhibit significant sequence homology to other glycosyltransferases, and thus, significant ambiguity about its catalytic mechanism remains. One of the major technical barriers in studying GS is the absence of activity assay methods that allow characterization of the lengths and amounts of (1,3)-ß-d-glucan due to its poor solubility in water and organic solvents. Here, we report a successful development of a novel GS activity assay based on size-exclusion chromatography coupled with pulsed amperometric detection and radiation counting (SEC-PAD-RC), which allows for the simultaneous characterization of the amount and length of the polymer product. The assay revealed that the purified yeast GS produces glucan with a length of 6550 ± 760 mer, consistent with the reported degree of polymerization of (1,3)-ß-d-glucan isolated from intact cells. Pre-steady state kinetic analysis revealed a highly efficient but rate-determining chain elongation rate of 51.5 ± 9.8 s-1, which represents the first observation of chain elongation by a nucleotide-sugar-dependent polysaccharide synthase. Coupling the SEC-PAD-RC method with substrate analogue mechanistic probes provided the first unambiguous evidence that GS catalyzes non-reducing end polymerization. On the basis of these observations, we propose a detailed model for the catalytic mechanism of GS. The approaches described here can be used to determine the mechanism of catalysis of other polysaccharide synthases.


Assuntos
Parede Celular/metabolismo , Glucosiltransferases/metabolismo , Saccharomyces cerevisiae/metabolismo , beta-Glucanas/metabolismo , Biocatálise , Cromatografia em Gel , Glucosiltransferases/química , Cinética , Polimerização , Proteoglicanas , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Especificidade da Espécie , beta-Glucanas/química , beta-Glucanas/isolamento & purificação
14.
J Korean Med Sci ; 35(1): e4, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31898433

RESUMO

BACKGROUND: The cognitive consequences and risk factors based long-term outcome of very-low-birth-weight (VLBW; < 1,500 g) infants in Korea has not been studied. The aim of this study was to determine the influence of perinatal and neonatal risk factors on the cognitive performance of VLBW children at 3 to 5 years of age. METHODS: We enrolled 88 VLBW infants without cystic periventricular leukomalacia for the assessment of their demographic data, cognitive performance, and development of cerebral palsy (CP) at 3 to 5 years of age. Cognitive performance was assessed using the Korean version of the Wechsler Preschool and Primary Scale of Intelligence IV. Growth data were assessed with measurements of weight, height, and head circumference (HC) at the corrected ages of 6, 12, and 18 months, and 3 to 5 years of age. RESULTS: In the VLBW group, the full-scale intelligence quotient (FSIQ) was 96.1 ± 15.2 at the mean age of 4.5 years. The incidence rate of CP was 3.4%. Overall, 17% (15/88) of the VLBW children had a below-average FSIQ (< 85). We divided the VLBW children into the abnormal FSIQ group (< 85, n = 15) and the normal FSIQ group (≥ 85, n = 73). VLBW children with intrauterine growth retardation (IUGR) was associated with a below-average FSIQ at the mean age of 4.5 years (< 85, 8/15, 53.3% vs. ≥ 85, 5/73, 6.8%; P < 0.001). After controlling for associated clinical factors, IUGR in the VLBW children was found to be associated with an abnormal FSIQ at the mean age of 4.5 years (P = 0.025). The weight, height, and HC obtained for both groups showed that normal growth was maintained at the mean age of 4.5 years with no significant difference between abnormal and normal FSIQ groups. CONCLUSION: Fifteen of 88 (17%) of the VLBW children had a below-average FSIQ (< 85). VLBW with IUGR is associated with poor cognitive outcomes at the mean age of 4.5 years.


Assuntos
Cognição/fisiologia , Recém-Nascido de muito Baixo Peso , Paralisia Cerebral/diagnóstico , Paralisia Cerebral/epidemiologia , Pré-Escolar , Feminino , Retardo do Crescimento Fetal/patologia , Idade Gestacional , Humanos , Testes de Inteligência , Modelos Lineares , Masculino , Razão de Chances , Estudos Prospectivos , República da Coreia/epidemiologia , Fatores de Risco , Tradução
15.
Transfus Med Hemother ; 47(1): 88-93, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32110199

RESUMO

BACKGROUND: DEL, the weakest D variant, is mistyped as D-negative by routine serological assays. Transfusion of red blood cells expressing the DEL phenotype has the potential to elicit anti-D alloimmunization in D-negative recipients. The goal of this study was to recommend DEL typing strategies for serologically D-negative Asian donors. METHODS: RhCE phenotyping and the adsorption-elution test were performed on 674 serologically D-negative samples. RHD genotyping using real-time polymerase chain reaction and melting curve analysis were also undertaken to identify DEL alleles. Costs and turnaround time of RhCE phenotyping, the adsorption-elution test, and RHD genotyping were estimated. RESULTS: Sensitivity and specificity of the adsorption-elution test for serologically D-negative samples were 94.9% (93/98) and 91.5% (527/576), respectively. C+ phenotypes were detected in all 98 samples with DEL alleles. Despite comparable costs, RHD genotyping was more accurate and rapid than the adsorption-elution test. CONCLUSIONS: Two practical DEL typing strategies using RhCE phenotyping as an initial screening method were recommended for serologically D-negative Asian donors. Compared with DEL typing using RHD genotyping, serological DEL typing using adsorption-elution test is predicted to increase the incidence of anti-D alloimmunization and decrease the D-negative donor pool without having any cost-competitiveness but can be used in laboratories where molecular methods are not applicable.

16.
Int J Mol Sci ; 21(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202940

RESUMO

In addition to the well-known diterpenoid steviol glycosides, Stevia rebaudiana (Stevia) produces many labdane-type diterpenoids and a wide range of mono- and sesquiterpenoids. However, biosynthesis of mono- and sesquiterpenoids in Stevia remains unknown. Here we analyzed the extracts of Stevia leaves, flowers, stems, and roots by Gas Chromatography-Mass Spectrometry and putatively identified a total of 69 volatile organic compounds, most of which were terpenoids with considerably varied quantities among the four tissues of Stevia. Using Stevia transcriptomes, we identified and functionally characterized five terpene synthases (TPSs) that produced major mono- and sesquiterpenoids in Stevia. Transcript levels of these Stevia TPSs and levels of corresponding terpenoids correlated well in Stevia tissues. Particularly, the root-specific SrTPS4 and SrTPS5 catalyzed the formation of γ-curcumene/zingiberene/ß-sesquiphellandrene and α-longipinene/ß-himachalene/himachalol as multifunctional sesqui-TPSs, respectively. Most of the SrTPSs were highly responsive to various environmental stresses in a tissue-specific manner. Taken together, our results provide new insights into how Stevia produces diverse terpenoids to confer differential responses to various environmental factors in each tissue.


Assuntos
Alquil e Aril Transferases/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/biossíntese , Stevia/enzimologia , Alquil e Aril Transferases/genética , Flores/enzimologia , Flores/genética , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Stevia/genética , Terpenos/metabolismo
17.
Plant Biotechnol J ; 17(6): 1037-1047, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30569490

RESUMO

Steviol glycosides (SGs) are extracted from Stevia leaves for use as a natural sweetener. Among SGs, stevioside is most abundant in leaf extracts followed by rebaudioside A (Reb A). However, Reb A is of particular interest because of its sweeter and more pleasant taste compared to stevioside. Therefore, the development of new Stevia varieties with a higher Reb A to stevioside ratio would be desirable for the production of higher quality natural sweeteners. Here, we generated transgenic Stevia plants overexpressing Stevia UDP-glycosyltransferase 76G1 (SrUGT76G1) that is known to convert stevioside to Reb A through 1,3-ß-d-glucosylation in vitro. Interestingly, by overexpressing SrUGT76G1, the Reb A to stevioside ratio was drastically increased from 0.30 in wild-type (WT) plants up to 1.55 in transgenic lines without any significant changes in total SGs content. This was contributed by a concurrent increase in Reb A content and a decrease in stevioside content. Additionally, we were able to find an increase in the Reb C to dulcoside A ratio in transgenic lines. Using the glutathione S-transferase-tagged SrUGT76G1 recombinant protein for an in vitro glucosyltransferase assay, we further demonstrated that Reb C can be produced from the glucosylation of dulcoside A by SrUGT76G1. Transgenic Stevia plants having higher Reb A to stevioside ratio were visually indistinguishable from WT plants. Taken together, our results demonstrate that the overexpression of SrUGT76G1 in Stevia is an effective way to generate new Stevia varieties with higher proportion of the more preferred Reb A without compromising on plant development.


Assuntos
Diterpenos do Tipo Caurano , Expressão Gênica , Glucosídeos , Stevia , Diterpenos do Tipo Caurano/química , Tecnologia de Alimentos , Glucosídeos/química , Glucosídeos/genética , Glicosiltransferases/genética , Folhas de Planta/química , Folhas de Planta/genética , Stevia/química , Stevia/genética , Difosfato de Uridina/genética
18.
Int J Syst Evol Microbiol ; 69(2): 493-497, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30566074

RESUMO

A Gram-stain-negative and strictly aerobic bacterium, designated DMHB-2T, was isolated from a sample of seawater collected off the Yellow Sea coast of the Republic of Korea. Cells were short rods and motile by means of a single polar flagellum. Catalase and oxidase activities were positive. Growth occurred at pH 5.5-10.0 (optimum, pH 6.0), 15-45 °C (optimum, 25 °C) and with 1-9 % NaCl (optimum, 3 %). The respiratory quinone was ubiquinone-8 and the major fatty acids were C16 : 0 (17.9 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 26.1 %) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c; 37.4 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain DMHB-2T belong to the genus Marinobacterium, with the highest 16S rRNA gene sequence similarity of 95.2 % to Marinobacterium zhoushanense KCTC 42782T. The genomic DNA G+C content of strain DMHB-2T was 60.8 mol%. On the basis of the phenotypic, chemotaxonomic and genotypic characteristics presented in this study, strain DMHB-2T is suggested to represent a novel species of the genus Marinobacterium, for which the name Marinobacteriumboryeongense sp. nov. is proposed. The type strain is DMHB-2T (=KACC 19225T=JCM 31902T).


Assuntos
Oceanospirillaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceanospirillaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
19.
J Org Chem ; 84(9): 4971-4991, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-30977652

RESUMO

Despite numerous advances in spectroscopic methods through the latter part of the 20th century, the unequivocal structure determination of natural products can remain challenging, and inevitably, incorrect structures appear in the literature. Computational methods that allow the accurate prediction of NMR chemical shifts have emerged as a powerful addition to the toolbox of methods available for the structure determination of small organic molecules. Herein, we report the structure determination of a small, stereochemically rich natural product from Laurencia majuscula using the powerful combination of computational methods and total synthesis, along with the structure confirmation of notoryne, using the same approach. Additionally, we synthesized three further diastereomers of the L. majuscula enyne and have demonstrated that computations are able to distinguish each of the four synthetic diastereomers from the 32 possible diastereomers of the natural product. Key to the success of this work is to analyze the computational data to provide the greatest distinction between each diastereomer, by identifying chemical shifts that are most sensitive to changes in relative stereochemistry. The success of the computational methods in the structure determination of stereochemically rich, flexible organic molecules will allow all involved in structure determination to use these methods with confidence.


Assuntos
Alquil e Aril Transferases/química , Alquil e Aril Transferases/síntese química , Alcinos/química , Laurencia/química , Alquil e Aril Transferases/isolamento & purificação , Técnicas de Química Sintética , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
20.
J Clin Pediatr Dent ; 43(1): 56-63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30289367

RESUMO

Treatment of horizontally and deeply impacted mandibular molars is challenging for both orthodontists and oral surgeons because of the limited access and anchorage control. We report on two patients who had horizontally and mesially impacted mandibular second molars (MM2s). Both patients were treated by a surgical orthodontic approach, and the crowns of the impacted teeth were brought into the arches by closed forced eruption. Mesially impacted MM2s were uprighted with orthodontic microimplants, inserted in the retromolar area, and then moved into their ideal position. The first patient was in an active growing stage, while the second patient was beyond the active growing stage. Therefore posterior available space (PAS) should be analyzed before treatment of impacted MM2s to prevent periodontal problems after uprighting of impacted teeth. If PAS is not enough for uprighting impacted MM2s, alternative treatment should be considered based on the stage of growth.


Assuntos
Técnicas de Movimentação Dentária , Dente Impactado , Assistência Odontológica , Humanos , Mandíbula , Dente Molar , Extrusão Ortodôntica , Dente Impactado/terapia
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