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1.
Medicine (Baltimore) ; 102(19): e33790, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37171320

RESUMEN

INTRODUCTION: Collateral circulation sustains cerebral perfusion in patients with arterial occlusion. Extensive arterial occlusion may redirect cerebral blood flow to compensate for insufficient perfusion. Cerebral artery occlusion can be observed in computed tomography perfusion imaging with increased mean transit time (MTT). However, in some cases, MTT delay occurs contralateral to the site of stenosis or occlusion. This delay cannot be explained simply by the collateral blood supply. Therefore, the authors considered the similarity of the perfusion delay observed at the normal site to that observed in subclavian steal syndrome. CASE PRESENTATION: Three patients were reviewed: the first had severe stenosis in the left proximal internal carotid artery (ICA), and the second had left common carotid artery occlusion and diffusion restriction of the ICA-middle carotid artery border zone. The third patient had total occlusion of the left common carotid artery and right proximal ICA, with multifocal infarctions in the right frontal, occipital, left frontal, and parietal lobes. All 3 patients had a contralateral MTT delay on perfusion imaging. CONCLUSION: The site of stenosis or occlusion did not correlate with ipsilateral perfusion delay in these 3 cases. Based on the precedent relationship between infarction and perfusion delay, we developed 2 hypotheses to explain why perfusion decreases on the contralateral side of the occlusion or stenosis. However, this study was limited because we could not identify events, like volume loss or decreased blood pressure, before stroke development.


Asunto(s)
Estenosis Carotídea , Accidente Cerebrovascular Isquémico , Humanos , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Constricción Patológica , Arteria Carótida Interna/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Perfusión , Circulación Cerebrovascular/fisiología
2.
Foods ; 10(10)2021 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-34681318

RESUMEN

The use of unmodified starch in frozen foods can cause extremely undesirable textural changes after the freeze-thaw process. In this study, using cyclodextrin glucanotransferase (CGTase) and branching enzymes, an amylopectin cluster with high freeze-thaw stability was produced, and was named CBAC. It was found to have a water solubility seven times higher, and a molecular weight 77 times lower, than corn starch. According to the results of a differential scanning calorimetry (DSC) analysis, dough containing 5% CBAC lost 19% less water than a control dough after three freeze-thaw cycles. During storage for 7 days at 4 °C, bread produced using CBAC-treated dough exhibited a 14% smaller retrogradation peak and 37% less hardness than a control dough, suggesting that CBAC could be a potential candidate for clean label starch, providing high-level food stability under repeated freeze-thaw conditions.

3.
Food Chem ; 345: 128777, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33321347

RESUMEN

Cyclodextrin glucanotransferase (CGTase; EC 2.4.1.19) produces cycloamyloses (CAs), which are large cyclic glucans, and subsequently transforms them to α-, ß-, and γ-cyclodextrins. We developed a novel encapsulation process based on the cyclization activity of CGTase and applied it to the formation of CA inclusion complexes with resveratrol (RVT), which has limited bioavailability due to its low water solubility. The encapsulated RVT (CA-RVT) was purified using preparative high-performance liquid chromatography. The water solubility of CA-RVT was 6,000-fold higher than that of RVT. CA-RVT in water demonstrated 98% stability for 1 week at 4 °C. According to radical scavenging activity and anti-inflammatory assays, CA-RVT in aqueous solution exhibited similar activities as an equal amount of RVT in dimethyl sulfoxide, suggesting the limited solubility of RVT can be overcome through CA encapsulation by CGTase, thus enhancing its nutraceutical value as a functional ingredient in the food industry.


Asunto(s)
Ciclodextrinas/química , Glucosiltransferasas/metabolismo , Resveratrol/química , Cápsulas , Ciclización , Ciclodextrinas/metabolismo , Solubilidad , Agua/química
4.
Food Sci Biotechnol ; 29(5): 667-674, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32419965

RESUMEN

To determine the physiochemical properties of the 4-α-glucanotransferase from Bifidobacterium sp., the bllj_0114 gene encoding 4-α-glucanotransferase was cloned from Bifidobacterium longum subsp. longum JCM 1217 and expressed in Escherichia coli. The amino acid sequence alignment indicated that the recombinant protein, named BL-αGTase, belongs to the glycoside hydrolase (GH) family 77. BL-αGTase was purified using nickel-nitrilotriacetic acid affinity chromatography and characterized using various substrates. The enzyme catalyzed the disproportionation activity, which transfers a glucosyl unit from oligosaccharides to acceptor molecules, and had the highest activity at 40 °C and pH 6.0. In the presence of 5 mM metal ions, in particular Cu2+, Zn2+, and Fe2+, BL-αGTase activity was reduced. To determine whether BL-αGTase can be used to generate thermoreversible gels, potato starch was treated with BL-αGTase for various reaction times. The BL-αGTase-treated starches showed sol-gel reversibility and melted at 59.6-75.7 °C.

5.
Int J Biol Macromol ; 152: 727-734, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32092418

RESUMEN

Bacteroides thetaiotaomicron (B. thetaiotaomicron), which resides in the human intestinal tract, has a number of carbohydrate enzymes, including glycoside hydrolase (GH) family 97. Only a few GH 97 enzymes have been characterized to date. In this study, a novel α-galactosidase (Bt_3294) was cloned from B. thetaiotaomicron, expressed in Escherichia coli, and purified using affinity chromatography. This novel enzyme showed optimal activity at 60 °C and pH 7.0. Enzyme activity was reduced by 94.4% and 95.7% in the presence of 5 mM Ca2+ and Fe2+, respectively. It is interesting that Bt_3294 specifically hydrolyzed shorter α-galactosyl oligosaccharides, such as melibiose and raffinose. The D-values of Bt_3294 at 40 °C and 50 °C were about 107 and 6 min, respectively. After immobilization of Bt_3294, the D-values at 40 °C and 50 °C were about 37.6 and 29.7 times higher than those of the free enzyme, respectively. As a practical application, the immobilized Bt_3294 was used to hydrolyze raffinose family oligosaccharides (RFOs) in soy milk, decreasing the RFOs by 98.9%.


Asunto(s)
Bacteroides thetaiotaomicron/metabolismo , Enzimas Inmovilizadas/metabolismo , Glicósido Hidrolasas/metabolismo , alfa-Galactosidasa/metabolismo , Concentración de Iones de Hidrógeno , Melibiosa/metabolismo , Oligosacáridos/metabolismo , Rafinosa/metabolismo , Leche de Soja/metabolismo
6.
J Ethnopharmacol ; 236: 108-113, 2019 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-30849503

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: According to traditional Korean medicine theory in which children's growth retardation is attributed to blood deficiency, Siwu decoction (SWD), a representative treatment for blood deficiency, was chosen as a sample. AIM OF THE STUDY: To evaluate the effects of SWD on chondrocyte proliferation of growth plate in adolescent female rats. MATERIALS AND METHODS: Female adolescent rats were allocated to one of the following four groups; SWD 100 and 300 mg/kg, recombinant human growth hormone, and vehicle for 4 days. Tetracycline was intraperitoneally injected at 48 h before sacrifice to obtain a band exhibiting fluorescence by binding newly formed bone. Bromodeoxyuridine was injected at day 2-4 to mark proliferating chondrocytes. To evaluate possible mechanisms of SWD, expressions of insulin-like growth factor-1 (IGF-1) and bone morphogenetic protein-2 (BMP-2) in the growth plate were examined by immunohistochemistry. RESULTS: Treatment with SWD significantly increased the number of BrdU-positive chondrocytes and the new bone formation in the proximal growth plate of tibia compared to the vehicle treated control group. SWD also increased the expression of IGF-1 and BMP-2 in the proliferative and hypertrophic zones of the growth plate. CONCLUSIONS: SWD 300 mg/kg stimulates chondrocyte proliferation and new bone formation in the growth plate. Immunohistochemical studies indicate that the effects of SWD may be due to upregulation of local IGF-1 and BMP-2 expression in the growth plate, which may be considered as a GH-dependent paracrine-autocrine pathway.


Asunto(s)
Desarrollo Óseo/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Placa de Crecimiento/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Proteína Morfogenética Ósea 2/biosíntesis , Condrocitos/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Placa de Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Medicina Tradicional Coreana , Ratas , Ratas Sprague-Dawley , Tibia/efectos de los fármacos , Tibia/metabolismo
7.
Maxillofac Plast Reconstr Surg ; 40(1): 23, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30202766

RESUMEN

BACKGROUND: Velopharyngeal insufficiency that accompanies speech resonance and articulation disorders can be managed through several intervention methods such as speech-language therapy, prosthetic aids, and surgery. However, for patients with severe hypernasality, surgical interventions are highly recommended. Among available surgical techniques, the posterior pharyngeal flap is most common. CASE PRESENTATION: Two adult males with high nasalance scores underwent superiorly based posterior pharyngeal flap surgery, followed by speech testing by an expert speech-language therapist. Nasalance scores and articulation accuracy were assessed up until 1 year after the surgery. Nasalance scores were measured five times using a nasometer, after which the average value was calculated. CONCLUSIONS: Consistent declines in hypernasality over time are not easy to explain since the pedicled pharyngeal flap narrowed over time, secondary to cicatrization. However, scar tethering of the soft palate in a posterior direction could reduce the velopharyngeal port size over time. Therefore, long-term follow-up with intensive speech therapy is suggested for patients with severe hypernasality.

8.
Maxillofac Plast Reconstr Surg ; 39(1): 9, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28497031

RESUMEN

BACKGROUND: Nasalance is used to evaluate the velopharyngeal incompetence in clinical diagnoses using a nasometer. The aim of this study is to find the nasalance differences between Vietnamese cleft palate children and Korean cleft palate children by measuring the nasalance of five oral vowels. METHODS: Ten Vietnamese cleft palate children after surgery, three Vietnamese children for the control group, and ten Korean cleft palate children after surgery with the same age participated in this experimentation. Instead of Korean control, the standard value of Korean version of the simplified nasometric assessment procedures (kSNAP) was used. RESULT: The results are as follows: (1) the highest nasalance score among the Vietnamese normal vowels is the low vowel /a/; however, that of Korean normal vowels is the high vowel /i/. (2) The average nasalance score of Korean cleft palate vowels is 18% higher than that of Vietnamese cleft palate vowels. There was a nasalance score of over 45% among the vowels /e/ and /i/ in Vietnamese cleft palate patients and /i/, /o/, and /u/ in Korean cleft palate patients. CONCLUSION: These different nasalance scores of the same vowels seem to cause an ethnic difference between Vietnamese and Korean cleft palate children.

9.
Clin Exp Otorhinolaryngol ; 10(3): 272-277, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27927010

RESUMEN

OBJECTIVES: Patients with bilateral vocal fold paralysis (BVFP) theoretically have difficulty producing voiceless consonants. However, perceptual studies have revealed clear production of voiceless consonants with good articulation scores in nontracheostomized patients. The purpose of this study was to clarify the production of voiceless stops during articulation in patients with BVFP compared to normal speakers. METHODS: The perceptual, acoustic, and aerodynamic characteristics of patients with BVFP and those with normal speech were investigated with special reference to voiceless stop consonants. Test words were prepared to place the stop consonants in different phonological environments, and were all nonsense words. RESULTS: The patients with BVFP perceptually produced the three types of stops successfully. However, they acoustically varied voice onset time to produce phonetically representative stops but decreased voice onset time of /ph/ and /p/ compared to those of normal speakers. These patients may properly control air pressure to produce the three types of stop consonants similar to normal speakers. CONCLUSION: The patients with BVFP realized the distinctions between the three types of stops similar to the normal speakers. Although vocal mobility was absent in the patients with BVFP, voice onset time, vowel duration, closure duration, and air pressure were similar to those of normal speakers.

10.
Clin Exp Otorhinolaryngol ; 9(2): 157-62, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27090273

RESUMEN

OBJECTIVES: The vocal changes after a thyroidectomy are temporary and nonsevere, therefore, obtaining accurate analytical results on the pathological vocal characteristics following such a procedure is difficult. For a more objective acoustic analysis, this study used the cepstral analysis method to examine changes in the patients' voices during the perioperative period regarding sustained vowel phonation. METHODS: The sustained phonation of the five vowels (i.e., /a/, /e/, /i/, /o/, and /u/) by 35 patients with thyroidectomy were recorded by using a Multi-Speech program. Of the 35 patients, 10 were men and 25 were women, with an average age of 51.5 years. Voice data were collected a total of 3 times (preoperatively, 5-7 days after the operation, and 6 weeks after the operation) and were edited according to each fragment (on-set, mid, and off-set) for cepstral analysis. RESULTS: The cepstral analysis on the patients' voices revealed no significant differences between the examination periods of all vowel phonations. However, analysis of the on-set fragment of the vowel /i/ revealed pathological characteristics in which the cepstral measurements of the voice were significantly lower after the operation than before the operation, with the cepstral measurements of the voice increasing further 6 weeks following surgery. CONCLUSION: The results of the acoustic analysis on the on-set fragment of the vowel /i/ will be important data for characterizing the vocal changes during the perioperative period. This study contributes to future research on the mechanisms underlying changes in the voice of patients with a history of thyroid or neck surgery.

11.
Artículo en Inglés | MEDLINE | ID: mdl-26925153

RESUMEN

The present study was to evaluate the effects of Huang Bai, Zhi Mu, Mai Ya, and Xia Ku Cao on hormone using the GT1-7 and GH3 cells. The GT1-7 and GH3 cell lines were incubated with DW; DMSO; and 30, 100, or 300 µg/mL of one of the four extract solutions in serum-free media for 24 hours. The MTT assay was performed to determine the cytotoxicity of the four herbs. The GT1-7 and GH3 cells were incubated in DW, estradiol (GT1-7 only), or noncytotoxic herb solutions in serum-free medium for 24 hours. A quantitative RT-PCR and western blot were performed to measure the GnRH expression in GT1-7 cells and GH expression in GH3 cells. Huang Bai, Zhi Mu, Xia Ku Cao, and Mai Ya inhibited the GnRH mRNA expression in GT1-7 cells, whereas Huang Bai enhanced GH mRNA expression in GH3 cells. Additionally, Xia Ku Cao inhibited GnRH protein expression in GT1-7 cells and Huang Bai promoted GH protein expression in GH3 cells. The findings suggest that Huang Bai can delay puberty by inhibiting GnRH synthesis in the hypothalamus while also accelerating growth by promoting GH synthesis and secretion in the pituitary.

12.
Maxillofac Plast Reconstr Surg ; 37(1): 22, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26258115

RESUMEN

Velopharyngeal dysfunction in cleft palate patients following the primary palate repair may result in nasal air emission, hypernasality, articulation disorder and poor intelligibility of speech. Among conservative treatment methods, speech aid prosthesis combined with speech therapy is widely used method. However because of its long time of treatment more than a year and low predictability, some clinicians prefer a surgical intervention. Thus, the purpose of this report was to increase an attention on the effectiveness of speech aid prosthesis by introducing a case that was successfully treated. In this clinical report, speech bulb reduction program with intensive speech therapy was applied for a patient with velopharyngeal dysfunction and it was rapidly treated by 5months which was unusually short period for speech aid therapy. Furthermore, advantages of pre-operative speech aid therapy were discussed.

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