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1.
Inorg Chem ; 61(33): 13058-13066, 2022 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-35838661

RÉSUMÉ

It is a great challenging task for selectivity control of both CO2 photoreduction and water splitting to produce syngas via precise microenvironment regulation. Herein, a series of UiO-type Eu-MOFs (Eu-bpdc, Eu-bpydc, Rux-Eu-bpdc, and Rux-Eu-bpydc) with different surrounding confined spaces were designed and synthesized. These photosensitizing Rux-Eu-MOFs were used as the molecular platform to encapsulate the [CoII4(dpy{OH}O)4(OAc)2(H2O)2]2+ (Co4) cubane cluster for constructing Co4@Rux-Eu-MOF (x = 0.1, 0.2, and 0.4) heterogeneous photocatalysts for efficient CO2 photoreduction and water splitting. The H2 and CO yields can reach 446.6 and 459.8 µmol·g-1, respectively, in 10 h with Co4@Ru0.1-Eu-bpdc as the catalyst, and their total yield can be dramatically improved to 2500 µmol·g-1 with the ratio of CO/H2 ranging from 1:1 to 1:2 via changing the photosensitizer content in the confined space. By increasing the N content around the cubane, the photocatalytic performance drops sharply in Co4@Ru0.1-Eu-bpydc, but with an enhanced proportion of CO in the final products. In the homogeneous system, the Co4 cubane was surrounding with Ru photosensitizers via week interactions, which can drive water splitting into H2 with >99% selectivity. Comprehensive structure-function analysis highlights the important role of microenvironment regulation in the selectivity control via constructing homogeneous and heterogeneous photocatalytic systems. This work provides a new insight for engineering a catalytic microenvironment of the cubane cluster for selectivity control of CO2 photoreduction and water splitting.


Sujet(s)
Dioxyde de carbone , Photosynthèse , Catalyse , Photosensibilisants , Eau
2.
Diabetes ; 69(12): 2700-2708, 2020 12.
Article de Anglais | MEDLINE | ID: mdl-32737116

RÉSUMÉ

The objective of this study was to compare the ratio of renal oxygen availability (RO2) to glomerular filtration rate (GFR), a measure of relative renal hypoxia, in adolescents with and without type 1 diabetes (T1D) and relate the ratio to albuminuria, renal plasma flow (RPF), fat mass, and insulin sensitivity (M/I). RO2 was estimated by blood oxygen level-dependent MRI; fat mass was estimated by DXA; GFR and RPF were estimated by iohexol and p-aminohippurate clearance; albuminuria was estimated by urine albumin-to-creatinine ratio (UACR); and M/I was estimated from steady-state glucose infusion rate/insulin (mg/kg/min) by hyperglycemic clamp in 50 adolescents with T1D (age 16.1 ± 3.0 years, HbA1c 8.6 ± 1.2%) and 20 control patients of similar BMI (age 16.1 ± 2.9 years, HbA1c 5.2 ± 0.2%). The RO2:GFR (ms/mL/min) was calculated as RO2 (T2*, ms) divided by GFR (mL/min). Whole-kidney RO2:GFR was 25% lower in adolescents with T1D versus control patients (P < 0.0001). In adolescents with T1D, lower whole-kidney RO2:GFR was associated with higher UACR (r = -0.31, P = 0.03), RPF (r = -0.52, P = 0.0009), and fat mass (r = -0.33, P = 0.02). Lower medullary RO2:GFR was associated with lower M/I (r = 0.31, P = 0.03). In conclusion, adolescents with T1D exhibited relative renal hypoxia that was associated with albuminuria and with increased RPF, fat mass, and insulin resistance. These data suggest a potential role of renal hypoxia in the development of diabetic kidney disease.


Sujet(s)
Diabète de type 1/complications , Hypoxie , Oxygène/métabolisme , Adiposité , Adolescent , Composition corporelle , Enfant , Diabète de type 1/métabolisme , Néphropathies diabétiques , Femelle , Furosémide , Débit de filtration glomérulaire , Technique du clamp glycémique , Hémoglobine glyquée/génétique , Hémoglobine glyquée/métabolisme , Humains , Insuline , Iohexol/pharmacologie , Mâle , Jeune adulte , Acide 4-amino-hippurique/pharmacologie
3.
Mem Inst Oswaldo Cruz ; 108(1): 41-7, 2013 Feb.
Article de Anglais | MEDLINE | ID: mdl-23440113

RÉSUMÉ

Heliconema hainanensis sp. nov. collected from Uroconger lepturus (Richardson) (Anguilliformes: Congridae), Muraenesox cinereus (Forsskål) and Congresox talabonoides (Bleeker) (Anguilliformes: Muraenesocidae) in the South China Sea was described using light and scanning electron microscopy. The new species differs from its congeners by the following morphology: pseudolabia, the number and arrangement of caudal papillae (4 pairs of pedunculate precloacal papillae arranged in 2 groups of 2 and 2 pairs and 6 pairs of pedunculate postcloacal papillae arranged in 4 groups of 1, 2, 1 and 2 pairs), the length of spicules [left spicule 0.51-0.69 mm, right spicule 0.20-0.27 mm, spicule (right:left) ratio 1:2.20-2.69] and the morphology of the female tail tip. In addition, specimens of the new species collected from the three different hosts and specimens of an unidentified species of Heliconema collected from U. lepturus were characterised using molecular methods by sequencing the internal transcribed spacer (ITS) of ribosomal DNA. Analyses and comparison of the ITS sequence of H. hainanensis sp. nov. with Heliconema sp. support the validity of the new species based on morphological observations. An identification key to the species of Heliconema is also provided.


Sujet(s)
Anguilliformes/parasitologie , Spirurina , Animaux , Chine , Femelle , Mâle , Microscopie électronique à balayage , Océan Pacifique , Spirurina/anatomie et histologie , Spirurina/classification , Spirurina/ultrastructure
4.
Mem. Inst. Oswaldo Cruz ; 108(1): 41-47, Feb. 2013. ilus, tab
Article de Anglais | LILACS | ID: lil-666042

RÉSUMÉ

Heliconema hainanensis sp. nov. collected from Uroconger lepturus (Richardson) (Anguilliformes: Congridae), Muraenesox cinereus (Forsskål) and Congresox talabonoides (Bleeker) (Anguilliformes: Muraenesocidae) in the South China Sea was described using light and scanning electron microscopy. The new species differs from its congeners by the following morphology: pseudolabia, the number and arrangement of caudal papillae (4 pairs of pedunculate precloacal papillae arranged in 2 groups of 2 and 2 pairs and 6 pairs of pedunculate postcloacal papillae arranged in 4 groups of 1, 2, 1 and 2 pairs), the length of spicules [left spicule 0.51-0.69 mm, right spicule 0.20-0.27 mm, spicule (right:left) ratio 1:2.20-2.69] and the morphology of the female tail tip. In addition, specimens of the new species collected from the three different hosts and specimens of an unidentified species of Heliconema collected from U. lepturus were characterised using molecular methods by sequencing the internal transcribed spacer (ITS) of ribosomal DNA. Analyses and comparison of the ITS sequence of H. hainanensis sp. nov. with Heliconema sp. support the validity of the new species based on morphological observations. An identification key to the species of Heliconema is also provided.


Sujet(s)
Animaux , Femelle , Mâle , Anguilliformes/parasitologie , Spirurina , Chine , Microscopie électronique à balayage , Océan Pacifique , Spirurina/anatomie et histologie , Spirurina/classification , Spirurina/ultrastructure
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