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1.
Inorg Chem ; 63(28): 13086-13092, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38937860

RESUMO

S-block single atoms represent an ideal catalyst for the oxygen reduction reaction (ORR) as they can suppress the Fenton reaction. However, the symmetry of the s/p orbitals tends to generate either an excessively strong or weak interaction with intermediates. Herein, Ca single atoms coordinated with -S, -OP, and three N atoms (Ca/NPS-HC) were fabricated to modulate the adsorption of intermediates and promote the efficiency of s-block ORR catalysts. The experimental results from ORR demonstrated that the Ca/NPS-HC catalyst exhibited outstanding catalytic capability with a half-wave potential of 0.89 V, a kinetic current density of 56.6 mA cm-2 at 0.85 V, and a Tafel slope of 42 mV dec-1, outperforming commercial Pt/C. The detailed mechanistic studies revealed that the asymmetric coordination of Ca single atoms led to the symmetry-breaking of electron distribution in Ca single atoms, attenuating the s-p hybridization from the intermediate adsorption process, and thereby minimizing the energy barrier of the whole ORR.

2.
Curr Med Res Opin ; 37(2): 261-267, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33351668

RESUMO

OBJECTIVE: The Chinese healthcare industry has immense potential for innovation and requires competent publication professionals for global reach. Changes in regulatory landscape of China necessitates pharmaceutical industries to collaborate with medical professionals who are capable of keeping up with both changes in regulations and innovative medicine. METHODS: We initiated an online questionnaire-based survey via WeChat from August 3 to August 14, 2019 which focused on experience level, challenges, career development, and training requirements of survey participants. RESULTS: A total of 53 medical publication professionals participated in this survey. Contrary to global trends, 77% of participants had <5 years of professional experience in publication, although only 36% of participants had <5 years of experience in healthcare industry. In all, 63% of respondents spent <50% of their time in publication-related activities, contributing to <10 manuscripts per year. Their expertise in manuscripts spanned clinical studies (68%), post-marketing studies (62%), and reviews (38%). Poor research design and data quality, limited medical writing skill, and inefficient communication with authors were major challenges for developing high-quality publications. Awareness of good publication practices guidelines was high (49%) and 15% of respondents were Certified Medical Publication Professionals. Strategic publication planning (72%), industry trends (66%), and best practices (55%) were some of training requirements identified to increase competencies among respondents. CONCLUSIONS: Although the Chinese medical publication professional industry is at a nascent stage, an attempt is being made to provide opportunities for its publication professionals to develop their competencies to match global standards.


Assuntos
Internacionalidade , Medicina , Publicações/estatística & dados numéricos , Inquéritos e Questionários , China , Humanos
3.
Brain Res ; 1216: 24-37, 2008 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-18486109

RESUMO

Early embryogenesis can reflect constituting organizations and evolutionary origins of brain areas. To determine whether a clear core-versus-shell distinction of neurogenesis that occurs from the auditory midbrain to the telencephalon in the reptile also appears in the bird, a single dose of [(3)H]-thymidine was injected into chick (Gallus gallus domesticus) eggs at some successive embryonic days (E) (from E3 to E10). Towards the end of hatching, [(3)H]-thymidine labeling was examined, and the results were as follows: 1) Neuronal generation in the nucleus intercollicularis (ICo) (shell region) began at E3, whereas neurogenesis began at E4 in the nucleus mesencephalicus lateralis pars dorsalis (MLd) (core region); 2) Neurogenesis initiated at E3 in the nucleus ovoidalis (Ov) shell, but initiated at E4 in the rostral Ov core. In the medial or caudal Ov core, the percentage of heavily-labeled neurons with [(3)H]-thymidine was significantly lower at E3 age group than that in the Ov shell; 3) In field L1 and L3, two flanking regions of the primary telencephalic auditory area (field L2a), neurogenesis started at E5, but started at E6 in field L2a. These data indicate that the onset of embryogenesis began earlier in the auditory shell areas than in the core areas from the midbrain to the telencephalon. These findings provide insight into the organization of auditory nuclei and their evolution in amniotes.


Assuntos
Vias Auditivas/embriologia , Neurônios/citologia , Teto do Mesencéfalo/embriologia , Telencéfalo/embriologia , Animais , Vias Auditivas/citologia , Diferenciação Celular , Embrião de Galinha , Galinhas , Embrião não Mamífero , Especificidade da Espécie , Células-Tronco/citologia , Teto do Mesencéfalo/citologia , Telencéfalo/citologia
4.
Brain Res ; 1107(1): 58-69, 2006 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-16842761

RESUMO

The hippocampus of songbirds plays an important role in spatial memory, and probably in song learning. Although prolonged neuronal generation and apoptosis are thought to be closely correlated with memory function, natural changes of the number of neurons and in apoptosis in the hippocampus of songbirds have not been fully investigated during development and in the adult. In the current study, we examined developmental changes in the volume and the number of neurons and apoptotic cells in the hippocampus of songbirds (Lonchura striata) from posthatch day (P5) to adulthood. Apoptotic cells were determined by Nissl staining and immunohistochemistry for cleaved caspase-3, a key apoptotic caspase executioner. The expression levels of Bcl-2 family member mRNA and protein, including Bcl-2, Bcl-xL and Bax, were also investigated. Our results indicated that: (1) the hippocampus volume significantly increased from P5 to P60, although the number of neurons remained stable in all studied stages; (2) the number of apoptotic cells was highest at P45, based either on the Nissl staining or on the immunohistochemistry for caspase-3; (3) Bcl-2 mRNA expression was high from P5 to adulthood, while Bax mRNA declined abruptly from P5 to adulthood, and Bcl-x mRNA was high after P45. Bcl-2 protein was only detected at P5 and P15, while detection of Bcl-xL and Bax proteins paralleled levels of mRNA expression. Our study provides detailed changes of apoptosis in the posthatch songbird hippocampus, suggesting an important role for caspase-3 and Bcl-2 family members in hippocampus apoptosis.


Assuntos
Apoptose/fisiologia , Expressão Gênica/fisiologia , Hipocampo/metabolismo , Dinâmica não Linear , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Caspase 3 , Caspases/metabolismo , Contagem de Células/métodos , Feminino , Tentilhões , Hipocampo/citologia , Hipocampo/crescimento & desenvolvimento , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Masculino , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
5.
J Comp Neurol ; 523(18): 2738-51, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26183901

RESUMO

Comparative embryonic studies are the most effective way to discern phylogenetic changes. To gain insight into the constitution and evolution of mammalian somatosensory thalamic nuclei, we first studied how calbindin (CB) and parvalbumin (PV) immunoreactivities appear during embryonic development in the first-order relaying somatosensory nuclei, i.e., the ventral posteromedial (VPM) and posterolateral (VPL) nuclei, and their neighboring higher-order modulatory regions, including the ventromedial or ventrolateral nucleus, posterior, and the reticular nucleus. The results indicated that cell bodies that were immunoreactive for CB were found earlier (embryonic day 12 [E12]) in the dorsal thalamus than were cells positive for PV (E14), and the adult somatosensory thalamus was characterized by complementary CB and PV distributions with PV dominance in the first-order relaying nuclei and CB dominance in the higher-order regions. We then labeled proliferating cells with [(3) H]-thymidine from E11 to 19 and found that the onset of neurogenesis began later (E12) in the first-order relaying nuclei than in the higher-order regions (E11). Using double-labeling with [(3) H]-thymidine autoradiography and CB or PV immunohistochemistry, we found that CB neurons were born earlier (E11-12) than PV neurons (E12-13) in the studied areas. Thus, similar to auditory nuclei, the first and the higher-order somatosensory nuclei exhibited significant distinctions in CB/PV immunohistochemistry and birthdates during embryonic development. These data, combined with the results of a cladistic analysis of the thalamic somatosensory nuclei, are discussed from an evolutionary perspective of sensory nuclei.


Assuntos
Calbindinas/metabolismo , Neurogênese , Parvalbuminas/metabolismo , Núcleos Talâmicos/citologia , Núcleos Talâmicos/metabolismo , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Autorradiografia , Embrião de Mamíferos , Camundongos , Neurônios , Núcleos Talâmicos/embriologia , Núcleos Talâmicos/crescimento & desenvolvimento , Timidina/metabolismo , Trítio/metabolismo
6.
Wei Sheng Yan Jiu ; 33(6): 737-40, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15727192

RESUMO

OBJECTIVE: To Evaluate dietary quality of type 2 diabetics in Macao with Healthy Eating Index and try to know whether the result from quantitative food frequency survey reflect the result from 24 hour recall dietary survey. METHODS: We randomly drew samples from file of registered type 2 diabetics on a Health Center of Macao. The diabetics have been investigated with both 24 hour dietary recall and quantitative food frequency dietary survey methods. According to the calculational method of healthy eating index, the result of dietary survey was transferred to Healthy Eating Index and evaluate the diet quality with it. RESULTS: There was a significant correlation between both results, including Healthy Eating Index, total energy and the percentages of energy from the three major nutrients, were obtained with 24 hour recall and quantitative food frequency. The Healthy Eating Index was 66.0. The minimum score of HEI components was milk. Total Energy of the diabetics was 5407.9 kJ (1287.6 kcal). And the percentages of energy from carbohydrate, total fat and protein were 59.4%, 25.8% and 16.1%, respectively. The intake of dietary fiber and calcium were 9.9 g and 340 mg respectively. CONCLUSION: For this population, the results of both dietary survey methods can reflect each other well. According to the criteria of Healthy Eating Index, diet quality of 80% patients were among "need improvement". The situation of milk consumption was the worst. The consumption of fruits, grains and vegetable were too low and the consumption of sodium was too high. The percentages of energy from the three major nutrients were within the recommended range but the intake of total energy was too low. The intake of thiamin and riboflavin were not enough. Intake of dietary fiber and calcium were severely low.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Dieta/normas , Ingestão de Alimentos , Adulto , Idoso , Inquéritos sobre Dietas , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Feminino , Humanos , Macau/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional
7.
J Comp Neurol ; 519(13): 2677-96, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21484802

RESUMO

To know the embryogenesis of the core and shell regions of the midbrain auditory nucleus, a single dose of [(3)H]-thymidine was injected into the turtle embryos at peak stages of neurogenesis in the shell and core of the torus semicircularis. Following sequential survival times, labeled neurons and the dynamics of cell proliferation were examined. The expression of vimentin (VM), reelin, calbindin, parvalbumin, and substance P were also studied. The results showed that: 1) progenitor cells for the core and shell regions were generated in different sites of the ventricular zone; 2) the length of the cell cycle or S-phase for the shell region were both longer than those for the core region (4.7 and 3.2 hours longer, respectively), suggesting that mitotic activity in the core region is higher than it is in the shell region; 3) the elongated cell bodies of the labeled core and shell cells had close apposition to VM fibers, suggesting that the migration of these cells is guided by VM fibers; 4) the germinal sites of the core and shell constructed by projecting the orientation of radial VM fibers back to the ventricular zone was consistent with those obtained by short and sequential survival [(3)H]-thymidine radiography; and 5) the beginning of positive staining for parvalbumin in the core region was interposed between those for calbindin and substance P in the shell regions. This study contributes to the understanding of how auditory nuclei are organized and how their components developed and evolved.


Assuntos
Vias Auditivas/anatomia & histologia , Vias Auditivas/embriologia , Mesencéfalo/anatomia & histologia , Mesencéfalo/embriologia , Neurônios/fisiologia , Tartarugas/anatomia & histologia , Tartarugas/embriologia , Animais , Calbindinas , Moléculas de Adesão Celular Neuronais/metabolismo , Proliferação de Células , Proteínas da Matriz Extracelular/metabolismo , Humanos , Proteínas do Tecido Nervoso/metabolismo , Neurônios/citologia , Parvalbuminas/metabolismo , Proteína Reelina , Proteína G de Ligação ao Cálcio S100/metabolismo , Serina Endopeptidases/metabolismo , Substância P/metabolismo , Timidina/metabolismo
8.
J Comp Neurol ; 515(5): 600-13, 2009 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-19480001

RESUMO

Early comparative embryogenesis can reflect the organization and evolutionary origins of brain areas. Neurogenesis in the auditory areas of sauropsids displays a clear core-to-shell distinction, but it remains unclear in mammals. To address this issue, [3H]-thymidine was injected into pregnant mice on consecutive embryonic (E) days (E10-E19) to date neuronal birthdays. Immunohistochemistry for substance P, calbindin, and parvalbumin was conducted to distinguish the core and shell auditory regions. The results showed that: 1) cell generation began at E13 in the external or dorsal nucleus of the inferior colliculus (IC), but it did not start in the caudomedial portion of the central nucleus of IC, and significantly fewer cells were produced in the medial and rostromedial portions of the central nucleus of IC; 2) cells were generated at E11 in the dorsal and medial divisions of the medial geniculate complex (MGd and MGm, respectively), whereas cell generation was absent in the medial and rostromedial portions of the ventral medial geniculate complex (MGv), and fewer cells were produced in the caudomedial portion of MGv; 3) in the telencephalic auditory cortex, cells were produced at E11 or E12 in layer I and the subplate, which receive projections from the MGd and MGm. However, cell generation occurred at E13-E18 in layers II-VI, including the area receiving projections from the MGv. The core-to-shell distinction of neurogenesis is thus present in the mesencephalic to telencephalic auditory areas in the mouse. This distinction of neurogenesis is discussed from an evolutionary perspective.


Assuntos
Córtex Auditivo , Evolução Biológica , Neurogênese/fisiologia , Animais , Córtex Auditivo/anatomia & histologia , Córtex Auditivo/embriologia , Córtex Auditivo/crescimento & desenvolvimento , Vias Auditivas/anatomia & histologia , Vias Auditivas/embriologia , Vias Auditivas/crescimento & desenvolvimento , Feminino , Idade Gestacional , Camundongos , Gravidez
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