Search results for "globin"
showing 10 items of 734 documents
Divergent roles of the Drosophila melanogaster globins.
2018
In contrast to long-held assumptions, the gene repertoire of most insects includes hemoglobins. Analyses of the genome of the fruitfly Drosophila melanogaster identified three distinct hemoglobin genes (glob1, glob2, and glob3). While glob1 is predominantly associated with the tracheal system and fat body, glob2 and glob3 are almost exclusively expressed in the testis. The physiological role of globins in Drosophila is uncertain. Here, we studied the functions of the three globins in a cell culture system. Drosophila Schneider 2 (S2) cells were stably transfected with each of the three globins and the empty vector as control. Under hypoxia (1% atmospheric O2), only glob1 overexpression enha…
Associations between food consumption patterns and saliva composition: Specificities of eating difficulties children
2017
Identifying objective markers of dietwould be beneficial to research fields such as nutritional epidemiology. As a preliminary study on the validity of using saliva for this purpose, and in order to explore the relationship between saliva and diet, we focused on clearly contrasted groups of children: children with eating difficulties (ED) receiving at least 50% of their energy intake through artificial nutrition vs healthy controls (C). Saliva of ED and C children was analyzed by various methods (targeted biochemical analyses, 2-D electrophoresis coupled to MS, 1H NMR) and their diet was characterized using food frequency questionnaires, considering 148 food items grouped into 13 categories…
Altered Semmes–Weinstein monofilament test results are associated with oxidative stress markers in type 2 diabetic subjects
2017
Abstract Background Different lines of evidence suggest that oxidative stress (OS) is implicated in the pathogenesis of diabetic neuropathy. The Semmes–Weinstein monofilament (SWM) test is an efficient tool for evaluating diabetic polyneuropathy and diabetic foot. In this study, we analyzed the association between OS markers and altered SWM test results in type 2 diabetes (T2DM) patients. Methods Seventy T2DM patients were studied and 34 showed altered SWM results. The clinical and biochemical parameters were determined using standardized methods. Levels of oxidized glutathione (GSSG) and malondialdehyde (MDA) were measured in circulating mononuclear cells using high-performance liquid chro…
The effects of pressure on the energy landscape of proteins
2018
AbstractProtein dynamics is characterized by fluctuations among different conformational substates, i.e. the different minima of their energy landscape. At temperatures above ~200 K, these fluctuations lead to a steep increase in the thermal dependence of all dynamical properties, phenomenon known as Protein Dynamical Transition. In spite of the intense studies, little is known about the effects of pressure on these processes, investigated mostly near room temperature. We studied by neutron scattering the dynamics of myoglobin in a wide temperature and pressure range. Our results show that high pressure reduces protein motions, but does not affect the onset temperature for the Protein Dynam…
Mitochondrial Changes in β0-Thalassemia/Hb E Disease.
2015
The compound β°-thalassemia/Hb E hemoglobinopathy is characterized by an unusually large range of presentation from essentially asymptomatic to a severe transfusion dependent state. While a number of factors are known that moderate presentation, these factors do not account for the full spectrum of presentation. Mitochondria are subcellular organelles that are pivotal in a number of cellular processes including oxidative phosphorylation and apoptosis. A mitochondrial protein enriched proteome was determined and validated from erythroblasts from normal controls and β°-thalassemia/Hb E patients of different severities. Mitochondria were evaluated through the use of mitotracker staining, analy…
The mitochondria-targeted antioxidant MitoQ modulates oxidative stress, inflammation and leukocyte-endothelium interactions in leukocytes isolated fr…
2016
It is not known if the mitochondria-targeted antioxidants such as mitoquinone (MitoQ) can modulate oxidative stress and leukocyte-endothelium interactions in T2D patients. We aimed to evaluate the beneficial effect of MitoQ on oxidative stress parameters and leukocyte-endothelium interactions in leukocytes of T2D patients. The study population consisted of 98 T2D patients and 71 control subjects. We assessed metabolic and anthropometric parameters, mitochondrial reactive oxygen species (ROS) production, glutathione peroxidase 1 (GPX-1), NFκB-p65, TNFα and leukocyte-endothelium interactions. Diabetic patients exhibited higher weight, BMI, waist circumference, SBP, DBP, glucose, insulin, HOMA…
Critical re-evaluation of neuroglobin expression reveals conserved patterns among mammals.
2016
Neuroglobin (Ngb) is a respiratory protein that is almost exclusively expressed in the vertebrate nervous system. Despite many years of research, the exact function and even the expression sites of Ngb are still a matter of debate. However, to investigate hypotheses surrounding the potential roles of Ngb, a detailed knowledge of its major and minor expression sites is indispensable. We have therefore evaluated Ngb expression by extensive bioinformatic analysis using publicly available transcriptome data (RNA-Seq). During mammalian brain development, we observed low embryonic expression of Ngb mRNA and an increase after birth, arguing against a role of Ngb in fetal hypoxia tolerance. In adul…
Ectopic myoglobin expression is associated with a favourable outcome in head and neck squamous cell carcinoma patients
2016
BACKGROUND/AIM: Ectopic myoglobin (MB) expression, mediated by alternative and hypoxia-inducible transcription, has recently been demonstrated in several epithelial tumours. This study aimed to examine the expression of MB in hormone-independent head and neck squamous cell carcinomas (HNSCCs). PATIENTS AND METHODS: Using imunohistochemistry, ectopic MB expression was analyzed on tissue microarrays (TMAs) of 524 patients with localized and locally advanced primary and recurrent HNSCC who had undergone surgical treatment with curative intent. Associations of MB expression with survival and clinicopathological parameters were analyzed. RESULTS: MB expression was found in 45.8% of HNSCC patient…
Femtosecond structural dynamics drives the trans/cis isomerization in photoactive yellow protein
2016
Many biological processes depend on detecting and responding to light. The response is often mediated by a structural change in a protein that begins when absorption of a photon causes isomerization of a chromophore bound to the protein. Pande et al. used x-ray pulses emitted by a free electron laser source to conduct time-resolved serial femtosecond crystallography in the time range of 100 fs to 3 ms. This allowed for the real-time tracking of the trans-cis isomerization of the chromophore in photoactive yellow protein and the associated structural changes in the protein.Science, this issue p. 725A variety of organisms have evolved mechanisms to detect and respond to light, in which the re…
TGF-β Serum Levels in Diabetic Retinopathy Patients and the Role of Anti-VEGF Therapy.
2020
Transforming growth factor &beta