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1.
Invest Ophthalmol Vis Sci ; 64(11): 23, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589983

RESUMO

Purpose: To assess age-related biometric changes of the eye in nonhuman primates (NHPs), to and decipher the growth and aging rates and their comparability with humans. Methods: Ocular anatomic measurements were performed on 341 macaca fascicularis aged 0.5 to 23 years via multimodal approaches including IOLMaster 700. Linear or polynomial regression models were simulated to determine the best fitted age-related function. The metrics were compared with human equivalents in published reports. Results: Macaques exhibited a postnatal eye growth pattern similar to humans, characterized by continuous eye extension coordinated with dramatic reshaping of the lens but not the cornea. The age-related growth of lens thickness (LT), anterior chamber depth (ACD), and axis length (AL) exhibited nonlinear and bipolar patterns. The inflection points were 10 to 12 years old for LT and ACD and 13 to 15 years old for AL in macaques, which were comparable in chronological age at a ratio of ∼1: ratio with that in humans. In contrast, the speed of aging, including the increase in lens density and the decrease in retinal nerve fiber layer thickness, was comparable in relative age at a ratio of ∼1:3 according to the differences in lifespan between macaques and humans. Lens density was a robust indicator for the aging process. Conclusions: Macaque eyes recapitulated the age-related process of human eyes to varying extents with different growth and aging rates. Chronological age or relative age should be considered in different scenarios when macaques are included in preclinical studies.


Assuntos
Envelhecimento , Cristalino , Animais , Humanos , Criança , Córnea , Retina , Macaca fascicularis
2.
J Biosci Bioeng ; 134(6): 528-533, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36224065

RESUMO

The intracellular NAD(P)H insufficiency is the key factor which limits the reduced product (such as chiral alcohols) synthesis by whole cell biocatalysis or microbial cell factory. In this paper, we reported a novel solution to increase NADPH supply through strengthening the pentose phosphate pathway (PPP) flux with overexpression of extra zwf (gene for glucose 6-phosphatedehydrogenase) and glk (gene for glucokinase) by recombinant Escherichia coli BL21(DE3)/pETDuet-1-glk-zwf and pET28a-bccr containing a carbonyl reductase gene bccr. The amount of intracellular NADPH was significantly increased from 150.3 µmol/L to 681.8 µmol/L after strengthening the PPP flux, which was 4.5-fold to that of the control. It was applied to improve the asymmetric reduction of 4-chloroacetoacetate to ethyl S-4-chloro-3-hydroxybutylate catalyzed by the BcCR, which increased the reaction yield 2.8-fold to the control. This strategy provides a new way to increase NADPH supply in E. coli cell factories.


Assuntos
Escherichia coli , Via de Pentose Fosfato , NADP , Escherichia coli/genética
3.
Transplantation ; 105(9): 1980-1988, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34416751

RESUMO

BACKGROUND: Type 1 diabetes (T1DM) is a chronic autoimmune disease characterized by T-cell-mediated destruction of insulin-producing beta cells. Evidence shows that patients with T1DM and mice used in specific diabetic models both exhibit changes in their intestinal microbiota and dysregulated microbiota contributes to the pathogenesis of T1DM. Islet transplantation (Tx) is poised to play an important role in the treatment of T1DM. However, whether treatment of T1DM with islet Tx can rescue dysregulated microbiota remains unclear. METHODS: In this study, we induced diabetic C57BL/6 mice with streptozotocin. Then treatment with either insulin administration, or homogenic or allogenic islet Tx was performed to the diabetic mice. Total DNA was isolated from fecal pellets and high-throughput 16S rRNA sequencing was used to investigate intestinal microbiota composition. RESULTS: The overall microbial diversity was comparable between control (nonstreptozotocin treated) and diabetic mice. Our results showed the ratio of the Bacteroidetes: Firmicutes between nondiabetic and diabetic mice was significant different. Treatment with islet Tx or insulin partially corrects the dysregulated bacterial composition. At the genus level, Bacteroides, Odoribacter, and Alistipes were associated with the progression and treatment efficacy of the disease, which may be used as a biomarker to predict curative effect of treatment for patients with T1DM. CONCLUSIONS: Collectively, our results indicate that diabetic mice show changed microbiota composition and that treatment with insulin and islet Tx can partially correct the dysregulated microbiota.


Assuntos
Bactérias/crescimento & desenvolvimento , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Microbioma Gastrointestinal , Controle Glicêmico , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Animais , Bactérias/classificação , Bactérias/genética , Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/microbiologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/microbiologia , Disbiose , Fezes/microbiologia , Transplante das Ilhotas Pancreáticas , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ribotipagem , Estreptozocina , Técnicas de Cultura de Tecidos
4.
J Vis Exp ; (156)2020 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-32116299

RESUMO

Pancreatic islet transplantation is a well-established therapeutic treatment for type 1 diabetes. The kidney capsule is the most commonly used site for islet transplantation in rodent models. However, the tight kidney capsule limits the transplantation of sufficient islets in large animals and humans. The inguinal subcutaneous white adipose tissue (ISWAT), a new subcutaneous space, was found to be a potentially valuable site for islet transplantation. This site has better blood supply than other subcutaneous spaces. Moreover, the ISWAT accommodates a larger islet mass than the kidney capsule, and transplantation into it is simple. This manuscript describes the procedure of mouse islet isolation and transplantation in the ISWAT site of syngeneic diabetic mouse recipients. Using this protocol, murine pancreatic islets were isolated by standard collagenase digestion and a basement membrane matrix hydrogel was used for fixing the purified islets in the ISWAT site. The blood glucose levels of the recipient mice were monitored for more than 100 days. Islet grafts were retrieved at day 100 after transplantation for histological analysis. The protocol for islet transplantation in the ISWAT site described in this manuscript is simple and effective.


Assuntos
Canal Inguinal/anatomia & histologia , Transplante das Ilhotas Pancreáticas , Modelos Biológicos , Gordura Subcutânea/transplante , Animais , Glicemia/metabolismo , Peso Corporal , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/terapia , Sobrevivência de Enxerto , Humanos , Ilhotas Pancreáticas/patologia , Camundongos Endogâmicos C57BL , Perfusão , Sobrevivência de Tecidos
5.
Biomed Res Int ; 2019: 1864168, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31915684

RESUMO

Caterpillar fungus is a well-known fungal Chinese medicine. To reveal molecular changes during early and late stages of adenosine biosynthesis, transcriptome analysis was performed with the anamorph strain of caterpillar fungus. A total of 2,764 differentially expressed genes (DEGs) were identified (p ≤ 0.05, |log2 Ratio| ≥ 1), of which 1,737 were up-regulated and 1,027 were down-regulated. Gene expression profiling on 4-10 d revealed a distinct shift in expression of the purine metabolism pathway. Differential expression of 17 selected DEGs which involved in purine metabolism (map00230) were validated by qPCR, and the expression trends were consistent with the RNA-Seq results. Subsequently, the predicted adenosine biosynthesis pathway combined with qPCR and gene expression data of RNA-Seq indicated that the increased adenosine accumulation is a result of down-regulation of ndk, ADK, and APRT genes combined with up-regulation of AK gene. This study will be valuable for understanding the molecular mechanisms of the adenosine biosynthesis in caterpillar fungus.


Assuntos
Adenosina/biossíntese , Hypocreales/genética , Hypocreales/metabolismo , Transcriptoma/genética , Perfilação da Expressão Gênica , Medicina Tradicional Chinesa , Redes e Vias Metabólicas/genética
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