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1.
J Org Chem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950197

RESUMO

Electron-rich diarylamines, exemplified by anisole-derived amines, play pivotal roles in process chemistry, pharmaceuticals, and materials. In this study, homo-diarylamines were synthesized directly from the C-H activation of electron-rich arenes by sodium nitrate/trifluoroacetic acid and the successive treatment of iron powder. Mechanistic investigations reveal that nitrosoarene serves as the reaction intermediate, and the formation of the second C-N bond between the resulting nitrosoarene and electron-rich arene is catalyzed by the nitrosonium ion (NO+). Thus, hetero-diarylamines were synthesized using preformed nitrosoarenes and various electron-rich arenes. This reaction complements a range of cross-coupling reactions catalyzed by transition metal catalysts.

2.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902305

RESUMO

Truffles are known worldwide for their peculiar taste, aroma, and nutritious properties, which increase their economic value. However, due to the challenges associated with the natural cultivation of truffles, including cost and time, submerged fermentation has turned out to be a potential alternative. Therefore, in the current study, the cultivation of Tuber borchii in submerged fermentation was executed to enhance the production of mycelial biomass, exopolysaccharides (EPSs), and intracellular polysaccharides (IPSs). The mycelial growth and EPS and IPS production was greatly impacted by the choice and concentration of the screened carbon and nitrogen sources. The results showed that sucrose (80 g/L) and yeast extract (20 g/L) yielded maximum mycelial biomass (5.38 ± 0.01 g/L), EPS (0.70 ± 0.02 g/L), and IPS (1.76 ± 0.01 g/L). The time course analysis of truffle growth revealed that the highest growth and EPS and IPS production was observed on the 28th day of the submerged fermentation. Molecular weight analysis performed by the gel permeation chromatography method revealed a high proportion of high-molecular-weight EPS when 20 g/L yeast extract was used as media and the NaOH extraction step was carried out. Moreover, structural analysis of the EPS using Fourier-transform infrared spectroscopy (FTIR) confirmed that the EPS was ß-(1-3)-glucan, which is known for its biomedical properties, including anti-cancer and anti-microbial activities. To the best of our knowledge, this study represents the first FTIR analysis for the structural characterization of ß-(1-3)-glucan (EPS) produced from Tuber borchii grown in submerged fermentation.


Assuntos
Glucanos , Polissacarídeos , Fermentação , Peso Molecular , Polissacarídeos/química
3.
Opt Express ; 30(15): 26690-26700, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236856

RESUMO

In this work, a novel design for the electrodes in a near quasi-single-mode (QSM) vertical-cavity surface-emitting laser (VCSEL) array with Zn-diffusion apertures inside is demonstrated to produce an effective improvement in the high-speed data transmission performance. By separating the electrodes in a compact 2×2 coupled VCSEL array into two parts, one for pure dc current injection and the other for large ac signal modulation, a significant enhancement in the high-speed data transmission performance can be observed. Compared with the single electrode reference, which parallels 4 VCSEL units in the array, the demonstrated array with its separated electrode design exhibits greater dampening of electrical-optical (E-O) frequency response and a larger 3-dB E-O bandwidth (19 vs. 15 GHz) under the same amount of total bias current (20 mA). Moreover, this significant improvement in dynamic performance does not come at the cost of any degradation in the static performance in terms of the maximum near QSM optical output power (17 mW @ 20 mA) and the Gaussian-like optical far-field pattern which has a narrow divergence angle (full-width half maximum (FWHM): 10° at 20 mA). The advantages of the separated electrode design lead to a much better quality of 32 Gbit/sec eye-opening as compared to that of the reference device (jitter: 1.5 vs. 2.8 ps) and error-free 32 Gbit/sec transmissions over a 500 m multi-mode fiber has been achieved under a moderate total bias current of 20 mA.

4.
Org Biomol Chem ; 19(47): 10390-10402, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34825694

RESUMO

Bromotrimethylsilane (TMSBr)-promoted intramolecular cyclization of (o-arylethynyl)benzyl ethers to form 1H-isochromenes at room temperature is reported. Further studies indicated that vinyl carbocations are the reaction intermediates which are stabilized by the conjugated aryl groups. Thus, O-addition of benzyl ethers/tetrahydropyrans to alkynes was achieved under metal-free, acidic conditions. These reaction conditions were compatible with an alkynyl Prins reaction; therefore, 1H-isochromenes were produced directly from alkynyl benzaldehydes and alkynyl alcohols using a one-pot procedure.

5.
Dev Comp Immunol ; 106: 103638, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32017956

RESUMO

Small heat shock proteins (shsps) are conserved across invertebrate species. They are implicated in the modulation of various biological processes, such as immune responses, abiotic stress tolerance metamorphosis, and embryonic development. Herein, we identified a heat shock protein 20 from the red swamp crayfish, Procambarus clarkii (named as Pc-Hsp20), and performed in vivo studies to elucidate its physiological functions in the innate immunity. The open reading frame of Pc-Hsp20 was 609 base pair, encoding a protein of 202 amino acid residues with a hsp20/alpha crystallin family domain. Pc-Hsp20 was ubiquitously expressed in various tissues; however, it was highest in the hepatopancreas. The challenge with immune elicitors remarkably enhanced the transcript level of Pc-Hsp20 in the hepatopancreas when compared with the control. Administration of double-stranded RNA could significantly reduce expression of the Pc-Hsp20 mRNAs, and most of the immune-related genes expression enhanced with a variable concentration in the hepatopancreas. Altogether, these results suggest that Pc-Hsp20 may participate in innate immunity against microbial pathogens.


Assuntos
Proteínas de Artrópodes/genética , Astacoidea/imunologia , Proteínas de Choque Térmico HSP20/genética , Hepatopâncreas/fisiologia , Infecções/imunologia , Animais , Proteínas de Artrópodes/metabolismo , Clonagem Molecular , Proteínas de Choque Térmico HSP20/metabolismo , Imunidade Inata , Filogenia , Domínios Proteicos/genética , RNA de Cadeia Dupla/imunologia , Alinhamento de Sequência , Estresse Fisiológico , Transcriptoma , alfa-Cristalinas/genética
6.
Int J Syst Evol Microbiol ; 70(3): 1672-1677, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935174

RESUMO

Strain XY-J91T, a Gram-stain-negative, reddish orange, non-spore-forming and short-rod-shaped marine bacterium, was isolated from rhizosphere soil of the mangrove plant Kandelia candel (L.) Druce in Mai Po Nature Reserve, Hong Kong. The strain showed growth at 15-50 °C (optimum 40 °C), at pH 5.5-9.5 (optimum 7.0-8.0) and with 0-8 % (w/v) NaCl (optimum 1-2 %). The only respiratory quinone was MK-7 and the major fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, an unidentified aminolipid and an unidentified phospholipid. The G+C content of strain XY-J91T was 40.4 mol%. Strain XY-J91T exhibited highest 16S rRNA gene sequence similarities to the type strains of Algoriphagus marincola SW-2T (96.66 %), Algoriphagus taiwanensis CC-PR-82T (96.21%), Algoriphagus ornithinivorans JC2052T (96.16%), Algoriphagus confluentis HJM-2T (95.73%) and Algoriphagus zhangzhouensis 12C11T (95.52 %). Based on the phylogenetic, phenotypic and chemotaxonomic evidence presented, strain XY-J91T represents a novel species of the genus Algoriphagus, for which the name Algoriphagus kandeliae sp. nov. is proposed. The type strain is XY-J91T (=MCCC 1K03612T=KCTC 72216T).


Assuntos
Bacteroidetes/classificação , Filogenia , Rhizophoraceae/microbiologia , Rizosfera , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hong Kong , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
PLoS One ; 10(10): e0141513, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26506095

RESUMO

BACKGROUND AND PURPOSE: Thalamostriate vein (TSV) is an important tributary of the internal cerebral vein, which mainly drains the basal ganglia and deep medulla. The purpose of this study was to explore the anatomic variation and quality of TSV and its smaller tributaries using susceptibility-weighted imaging (SWI). METHODS: We acquired SWI images in 40 volunteers on a 3.0T MR system using an 8-channel high-resolution phased array coil. The frequencies of the TSV and its tributaries were evaluated. We classified TSV into types I (forming a venous angle) and II (forming a false venous angle). We classified anterior caudate vein (ACV)into types 1 (1 trunk) and 2 (2 trunks) as well as into types A (joiningTSV), B (joining anterior septal vein), and C (joining the angle of both veins). RESULTS: The TSV drains the areas of caudate nucleus, internal capsule,lentiform nucleus, external capsule, claustrum, extreme capsule and the white matter of the frontoparietal lobes,except thalamus. The frequencies of the TSV, ACV and transverse caudate vein (ACV) were 92.5%, 87.5% and 63.8%, respectively. We found TSV types I and II in 79.7%, and 20.3% with significantly different constitution ratios (P< 0.05). The most common types of ACV were type 1 (90.0%) and type A (64.3%). CONCLUSION: The complex three-dimensional (3D) venous architecture of TSV and its small tributaries manifests great variation, with significant and practical implications for neurosurgery.


Assuntos
Variação Anatômica , Veias Cerebrais/anatomia & histologia , Diagnóstico por Imagem , Imageamento por Ressonância Magnética , Adulto , Núcleo Caudado/anatomia & histologia , Núcleo Caudado/diagnóstico por imagem , Córtex Cerebral/irrigação sanguínea , Veias Cerebrais/diagnóstico por imagem , Feminino , Humanos , Veias Jugulares/anatomia & histologia , Veias Jugulares/diagnóstico por imagem , Masculino , Radiografia , Tálamo/irrigação sanguínea
8.
Neuroradiology ; 57(2): 163-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25326168

RESUMO

INTRODUCTION: The venous network of the brainstem is complex and significant. Susceptibility-weighted imaging (SWI) is a practical technique which is sensitive to veins, especially tiny veins. Our purpose of this study was to evaluate the visualization of the venous network of brainstem by using SWI at 3.0 T. METHODS: The occurrence rate of each superficial veins of brainstem was evaluated by using SWI on a 3 T MR imaging system in 60 volunteers. The diameter of the lateral mesencephalic vein and peduncular vein were measured by SWI using the reconstructed mIP images in the sagittal view. And the outflow of the veins of brainstem were studied and described according to the reconstructed images. RESULTS: The median anterior pontomesencephalic vein, median anterior medullary vein, peduncular vein, right vein of the pontomesencephalic sulcus, and right lateral anterior pontomesencephalic vein were detected in all the subjects (100%). The outer diameter of peduncular vein was 1.38 ± 0.26 mm (range 0.8-1.8 mm). The lateral mesencephalic vein was found in 75% of the subjects and the mean outer diameter was 0.81 ± 0.2 mm (range 0.5-1.2 mm). The inner veins of mesencephalon were found by using SWI. CONCLUSION: The venous networks around the brain stem can be visualized by SWI clearly. This result can not only provide data for anatomical study, but also may be available for the surgical planning in the infratentorial region.


Assuntos
Tronco Encefálico/anatomia & histologia , Tronco Encefálico/irrigação sanguínea , Veias Cerebrais/anatomia & histologia , Imagem de Difusão por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Taiwan J Obstet Gynecol ; 50(2): 172-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21791303

RESUMO

OBJECTIVE: To provide sectional anatomic data for the precise localization of developmental malformation of fetal brain in sagittal magnetic resonance imaging (MRI). METHOD: After abdominal and pelvic MRI scanning, the gravid specimen was cut into serial sagittal slices in correspondence with MRI in a low temperature laboratory to demonstrate the structures of fetal brain. RESULT: (1) Directional determination of the sloping and rotating fetal head. From the serial sagittal sections of pregnant cadaver at term, we concluded that, the longitudinal lying and cephalic presentation fetal had run into maternal pelvis, and rotated and sloped to right. Anteroposterior position and median sagittal plane of the fetal was in correspondence with his mother's. (2) Seven serial sagittal sections of the fetal brain were obtained through lateral surface of the right cerebral hemisphere, lateral sulcus, internal capsule, median sagittal plane, middle cerebellar peduncle, brainstem, and lateral surface of the left cerebral hemisphere. CONCLUSION: Through the comparison study between sagittal sections and corresponding MRI of fetal brain at term, we could obtain morphological anatomic structures and MRI of fetal brain, providing morphological demonstration of the intrauterine development of fetal brain and auxiliary diagnosis of ultrasound and MRI in pregnant woman.


Assuntos
Encéfalo/embriologia , Desenvolvimento Fetal , Feto/anatomia & histologia , Imageamento por Ressonância Magnética , Anormalidades Congênitas/diagnóstico , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez
10.
World J Cardiol ; 2(4): 89-97, 2010 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21160703

RESUMO

AIM: To assess neovascularization within human carotid atherosclerotic soft plaques in patients with ischemic stroke. METHODS: Eighty-one patients with ischemic stroke and 95 patients without stroke who had soft atherosclerotic plaques in the internal carotid artery were studied. The thickest soft plaque in each patient was examined using contrast-enhanced ultrasound. Time-intensity curves were collected from 5 s to 3 min after contrast injection. The neovascularization within the plaques in the internal carotid artery was evaluated using the ACQ software built into the scanner by 2 of the experienced investigators who were blinded to the clinical history of the patients. RESULTS: Ischemic stroke was present in 7 of 33 patients (21%) with grade I plaque, in 14 of 51 patients (28%) with grade II plaque, in 26 of 43 patients (61%) with grade III plaque, and in 34 of 49 patients (69%) with grade IV plaque (P < 0.001 comparing grade IV plaque with grade I plaque and with grade II plaque and P = 0.001 comparing grade III plaque with grade I plaque and with grade II plaque). Analysis of the time intensity curves revealed that patients with ischemic stroke had a significantly higher intensity of enhancement (IE) than those without ischemic stroke (P < 0.01). The wash-in time (WT) of plaque was significantly shorter in stroke patients (P < 0.05). The sensitivity and specificity for IE in the plaque were 82% and 80%, respectively, and for WT were 68% and 74%, respectively. There was no significant difference in the peak intensity or time to peak between the 2 groups. CONCLUSION: This study shows that the higher the grade of plaque enhancement, the higher the risk of ischemic stroke. The data suggest that the presence of neovascularization is a marker for unstable plaque.

11.
Turk Neurosurg ; 20(2): 151-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20401842

RESUMO

AIM: To explore a method to obtain sub-millimeter data of the thin transverse section of the pterygopalatine fossa (PPF), and to study the thin transverse sectional anatomy of the adult pterygopalatine fossa and its communicating structure for providing anatomic gist for the imaging diagnosis and minimal invasive operation when PPF diseased. MATERIAL AND METHODS: Two heads of adult cadaver without macroscopic trauma (four sides of PPF) were selected to observe. Images of 0.6 mm-thick multi-planar construction (MPR) were obtained with multislice spiral CT (MSCT) based on the superior orbitomeatal line. Then, the specimens were sliced into 0.1 mm serial section on the transverse plane with the computerized milling machine, the figures were taken with digital camera and the sectional data were stored in the computer. Lastly, the thin transversal section of PPF was investigated and compared with multislice spiral CT images acquired by MPR technique to explore and discuss the anatomy of the thin transverse section of the internal structure of PPF. RESULTS: PPF was divided into four portions: infrapterygopalatine portion, pterygopalatine ganglionic one, suprapterygopalatine one and roof of PPF according to the structural characteristics of the transverse section of PPF. The infrapterygopalatine portion communicated laterally with the infratemporal fossa through the pterygomaxillary fissure and communicated downwards with the oral cavity via palatine greater and lesser canals. The pterygopalatine ganglion was shown clearly in the pterygopalatine ganglionic portion, and its dimensions were 3.91x1.92 mm at the best layer. In the suprapterygopalatine portion, the sphenopalatine foramen and artery were obviously shown on the medial wall, while the palatovaginal canal and artery, the pterygoid canal and artery, and the foramen rotundum and maxillary nerve were shown from the inferiomedial to laterosuperior on the posterior wall. The vomerovaginal canal and artery were located at the slightly superior portion of the medial side of the palatovaginal canal. CONCLUSION: Figures of thin transverse section and multislice spiral CT have highly consistency for the display of PPF. Both of them can correctly identify the micro-structure, the complex relationship of the connectivity and the spatial localization in the narrow space of PPF. It can provide reference gist for the imaging diagnosis and minimal invasive operation.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos , Procedimentos Neurocirúrgicos , Fossa Pterigopalatina/anatomia & histologia , Fossa Pterigopalatina/diagnóstico por imagem , Tomografia Computadorizada Espiral , Adulto , Cadáver , Artérias Cerebrais/anatomia & histologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/cirurgia , Cistos Glanglionares/diagnóstico por imagem , Cistos Glanglionares/cirurgia , Humanos , Palato Duro/anatomia & histologia , Palato Duro/diagnóstico por imagem , Palato Duro/cirurgia , Cuidados Pré-Operatórios , Fossa Pterigopalatina/cirurgia
12.
J Chin Med Assoc ; 72(10): 515-20, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19837645

RESUMO

BACKGROUND: The purpose of this study was to provide practical data for the imaging diagnosis of the optic pathways. METHODS: Sectional anatomy of the optic pathways on the coronal plane was investigated on 15 sets of serial coronal sections of the head of Chinese adult cadavers and 6 sets of serial coronal magnetic resonance imaging of normal adults. RESULTS: On the coronal plane, we recognized the special structures of optic pathways by 5 key sections. (1) The midorbital optic nerve lay superomedially in the center of the adipose body of the orbit, surrounded by the subarachnoid space and the sheath of the optic nerve. (2) The optic chiasma was transverse between the optic and infundibular recesses of the portion of the floor of the third ventricle and it lay below the A1 segment of the anterior cerebral artery and above the tuber cinereum and the pituitary stalk, C2 or C3 segment of the internal carotid artery laterally. (3) The optic tract lay between the crus cerebri and the amygdaloid, the tail of the caudate nucleus laterally. The anterior choroidal artery inferiorly and downward M2 segment of the middle cerebral artery lay between the uncus and the crus cerebri. (4) The lateral geniculate body lay between the crus cerebri medially and the tail of the caudate nucleus laterally, the uncus and P2 segment of the posterior cerebral artery inferiorly. (5) The optic radiation formed the lateral wall of the lateral ventricle both in the temporal horn and in the occipital horn. The optic radiation was separated from the wall of the occipital horn by the tapetum, a thin layer of fibers derived from the splenium of the corpus callosum. Coronal sectional anatomy and magnetic resonance imaging of the optic pathways revealed similar results. CONCLUSION: This study provides a good understanding of the structures of the optic pathways by correlation of coronal sections of the head of adult cadavers with the coronal magnetic resonance images of normal adults.


Assuntos
Corpos Geniculados/anatomia & histologia , Quiasma Óptico/anatomia & histologia , Nervo Óptico/anatomia & histologia , Vias Visuais/anatomia & histologia , Adulto , Feminino , Humanos , Masculino
13.
Psychiatr Serv ; 56(5): 599-601, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15872170

RESUMO

The aims of this study were to assess self-stigma among Taiwanese outpatients with depressive disorders and to examine the factors related to self-stigma. Using the Self-Stigma Assessment Scale, the authors evaluated 247 outpatients with depressive disorders to determine their levels of self-stigma. The relationships between self-stigma and severity of depressive symptoms, sociodemographic characteristics, and course of illness were further examined. Sixty-two patients (25 percent) had high levels of self-stigma. Patients who had more severe depression and less education had higher levels of self-stigma. Clinicians should take self-stigma into consideration when communicating with depressed patients, especially those with characteristics associated with high levels of self-stigma.


Assuntos
Depressão/psicologia , Autoimagem , Estereotipagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Taiwan
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