Uranium Reduction by Desulfovibrio desulfuricans Strain G20 and a Cytochrome c3 Mutant

ABSTRACT Previous in vitro experiments with Desulfovibrio vulgaris strain Hildenborough demonstrated that extracts containing hydrogenase and cytochrome c 3 could reduce uranium(VI) to uranium(IV) with hydrogen as the electron donor. To test the involvement of these proteins in vivo, a cytochrome c 3 mutant of D. desulfuricans strain G20 was assayed and found to be able to reduce U(VI) with lactate or pyruvate as the electron donor at rates about one-half of those of the wild type. With electrons from hydrogen, the rate was more severely impaired. Cytochrome c 3 appears to be a part of the in vivo electron pathway to U(VI), but additional pathways from organic donors can apparently bypass this protein.

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Effect of α-melanocyte-stimulating hormone on tyrosinase activity in hair follicular and epidermal melanocytes of the mouse

Journal of Endocrinology ◽

10.1677/joe.0.1190517 ◽

1988 ◽

Vol 119 (3) ◽

pp. 517-522 ◽

Cited By ~ 8

Author(s):

P. Seechurn ◽

S. A. Burchill ◽

A. J. Thody

Keyword(s):

Tyrosinase Activity ◽

In Vitro Experiments ◽

Dorsal Skin ◽

Wild Type ◽

Melanocyte Stimulating Hormone ◽

Tyrosinase Expression ◽

In Vivo Administration ◽

Agouti Gene

ABSTRACT In this study, the effect of α-MSH on tyrosinase activity was compared in epidermal and hair follicular melanocytes of mice. It had no effect on epidermal tyrosinase activity in dorsal skin from neonatal non-agouti black mice (C57BL/6J) in both in-vivo and in-vitro experiments. Theophylline and 8-bromocyclic (c)AMP were similarly without effect in in-vitro experiments. In-vivo administration of α-MSH and theophylline for 7 days was also without effect on epidermal tyrosinase activity in ear skin of adult non-agouti mice, and the same was true for α-MSH in wild-type agouti mice. Activation of the epidermal melanocytes in the non-agouti and wild-type agouti mice with ultraviolet radiation also failed to bring about a response to α-MSH and to theophylline in the case of the former. No tyrosinase activity was detected in the epidermis of viable yellow mice (C3H-HeAvy), but, as shown previously, tyrosinase activity was present in the hair follicle when the hair was actively growing and was increased in those mice given either α-MSH or theophylline. α-MSH and theophylline had no such effects on hair follicular tyrosinase activity in the non-agouti mice. The present results suggest that α-MSH- and cAMP-dependent mechanisms have little or no importance in the regulation of tyrosinase expression in mouse epidermal melanocytes. α-MSH may, however, regulate tyrosinase expression in hair follicular melanocytes, but even in these melanocytes its action may be restricted to mice that express the agouti gene. J. Endocr. (1988) 119, 517–522

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PGI synthase overexpression protects against bleomycin-induced mortality and is associated with increased Nqo 1 expression

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00224.2010 ◽

2011 ◽

Vol 301 (4) ◽

pp. L615-L622 ◽

Cited By ~ 14

Author(s):

Weisong Zhou ◽

Dustin R. Dowell ◽

Mark W. Geraci ◽

Timothy S. Blackwell ◽

Robert D. Collins ◽

...

Keyword(s):

Airway Epithelium ◽

Death Rate ◽

Treatment Strategies ◽

Oxygen Species ◽

In Vitro Experiments ◽

Wild Type ◽

Potential Therapeutic Target ◽

First Time

The mortality rate for acute lung injury (ALI) is reported to be between 35–40%, and there are very few treatment strategies that improve the death rate from this condition. Previous studies have suggested that signaling through the prostaglandin (PG) I2 receptor may protect against bleomycin-induced ALI in mice. We found that mice that overexpress PGI synthase (PGIS) in the airway epithelium were significantly protected against bleomycin-induced mortality and had reduced parenchymal consolidation, apoptosis of lung tissue, and generation of F2-isoprostanes compared with littermate wild-type controls. In addition, we show for the first time in both in vivo and in vitro experiments that PGI2 induced the expression of NADP (H): quinoneoxidoreductase 1 (Nqo 1), an enzyme that prevents the generation of reactive oxygen species. PGI2 induction of Nqo 1 provides a possible novel mechanism by which this prostanoid protects against bleomycin-induced mortality and identifies a potential therapeutic target for human ALI.

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In Vivo Evidence for Instability of Episomal Human Immunodeficiency Virus Type 1 cDNA

Journal of Virology ◽

10.1128/jvi.79.8.5203-5210.2005 ◽

2005 ◽

Vol 79 (8) ◽

pp. 5203-5210 ◽

Cited By ~ 71

Author(s):

Mark Sharkey ◽

Karine Triques ◽

Daniel R. Kuritzkes ◽

Mario Stevenson

Keyword(s):

Viral Replication ◽

In Vitro Experiments ◽

Plasma Viremia ◽

Wild Type ◽

Immunodeficiency Virus ◽

Hiv 1

ABSTRACT Current regimens for the management of human immunodeficiency virus type 1 (HIV-1) infection suppress plasma viremia to below detectable levels for prolonged intervals. Nevertheless, there is a rapid resumption in plasma viremia if therapy is interrupted. Attempts to characterize the extent of viral replication under conditions of potent suppression and undetectable plasma viremia have been hampered by a lack of convenient assays that can distinguish latent from ongoing viral replication. Using episomal viral cDNA as a surrogate for ongoing replication, we previously presented evidence that viral replication persists in the majority of infected individuals with a sustained aviremic status. The labile nature of viral episomes and hence their validity as surrogate markers of ongoing replication in individuals with long-term-suppressed HIV-1 infection have been analyzed in short-term in vitro experiments with conflicting results. Since these in vitro experiments do not shed light on the long-term in vivo dynamics of episomal cDNA or recapitulate the natural targets of infection in vivo, we have analyzed the dynamics of episomal cDNA turnover in vivo by following the emergence of an M184V polymorphism in plasma viral RNA, in episomal cDNA, and in proviral DNA in patients on suboptimal therapies. We demonstrate that during acquisition of drug resistance, wild-type episomal cDNAs are replaced by M184V-harboring episomes. Importantly, a complete replacement of wild-type episomes with M184V-containing episomes occurred while proviruses remained wild type. This indicates that episomal cDNAs are turned over by degradation rather than through death or tissue redistribution of the infected cell itself. Therefore, evolution of episomal viral cDNAs is a valid surrogate of ongoing viral replication in HIV-1-infected individuals.

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Evaluation of 2′-Deoxy-2′-Flouro-5-Methyl-1-β-d-Arabinofuranosyluracil as a Potential Gene Imaging Agent for HSV-tk Expression In Vivo

Molecular Imaging ◽

10.1162/15353500200202100 ◽

2002 ◽

Vol 1 (2) ◽

pp. 153535002002021

Author(s):

Mian M. Alauddin ◽

Atranik Shahinian ◽

Erlinda M. Gordon ◽

Peter S. Conti

Keyword(s):

Emission Tomography ◽

In Vivo Studies ◽

In Vitro Experiments ◽

Tumor Uptake ◽

Wild Type ◽

Positron Emission ◽

Additional Tumor ◽

Ht 29

2′-Deoxy-2′-flouro-5-methyl-1-β-d-arabinofuranosyluracil (FMAU) has been evaluated in HT-29 cells as a potential positron emission tomography (PET) radiotracer for imaging HSV-tk gene expression in vivo. In vitro experiments demonstrate that the accumulation of [14C]-FMAU in HSV-tk-expressing cells is 2.4-fold ( p < .02), 4.0-fold ( p < .001), and 5.3-fold ( p < .001) higher than the wild-type cells at 1, 3, and 5 hr, respectively. In vivo studies revealed that the tumor uptake in HSV-tk-expressing cells was 2.3-fold ( p < .001), 3.0-fold ( p < .001), and 5.5-fold ( p < .001) higher than the control cells at 1, 2, and 5 hr, respectively. FMAU was found to be more sensitive compared to our earlier studies using 9-[(3-18F-fluoro-1-hydroxy-2-propoxy)methyl]-guanine ([18F]-FHPG) and 9-(4-[18F]-fluoro-3-hydroxy-methylbutyl)guanine ([18F]-FHBG) in the same cell lines, although, the specificity was less than FHBG. These results suggest that while FMAU labeled with PET isotopes may be useful for imaging HSV-tk-expressing tumors in vivo, multitracer studies across additional tumor models are necessary in order to identify an optimal PET radiotracer.

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Arabidopsis Disulfide Reductase, Trx-h2, Functions as an RNA Chaperone under Cold Stress

Applied Sciences ◽

10.3390/app11156865 ◽

2021 ◽

Vol 11 (15) ◽

pp. 6865

Author(s):

Eun Seon Lee ◽

Joung Hun Park ◽

Seong Dong Wi ◽

Ho Byoung Chae ◽

Seol Ki Paeng ◽

...

Keyword(s):

Cold Stress ◽

Wild Type ◽

Rna Chaperone ◽

E Coli ◽

Cold Sensitive ◽

Thioredoxin H ◽

Functional Rnas

The thioredoxin-h (Trx-h) family of Arabidopsis thaliana comprises cytosolic disulfide reductases. However, the physiological function of Trx-h2, which contains an additional 19 amino acids at its N-terminus, remains unclear. In this study, we investigated the molecular function of Trx-h2 both in vitro and in vivo and found that Arabidopsis Trx-h2 overexpression (Trx-h2OE) lines showed significantly longer roots than wild-type plants under cold stress. Therefore, we further investigated the role of Trx-h2 under cold stress. Our results revealed that Trx-h2 functions as an RNA chaperone by melting misfolded and non-functional RNAs, and by facilitating their correct folding into active forms with native conformation. We showed that Trx-h2 binds to and efficiently melts nucleic acids (ssDNA, dsDNA, and RNA), and facilitates the export of mRNAs from the nucleus to the cytoplasm under cold stress. Moreover, overexpression of Trx-h2 increased the survival rate of the cold-sensitive E. coli BX04 cells under low temperature. Thus, our data show that Trx-h2 performs function as an RNA chaperone under cold stress, thus increasing plant cold tolerance.

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Neuroprotective Potential of a Small Molecule RET Agonist in Cultured Dopamine Neurons and Hemiparkinsonian Rats

Journal of Parkinson s Disease ◽

10.3233/jpd-202400 ◽

2021 ◽

pp. 1-24

Author(s):

Juho-Matti Renko ◽

Arun Kumar Mahato ◽

Tanel Visnapuu ◽

Konsta Valkonen ◽

Mati Karelson ◽

...

Keyword(s):

Mapk Signaling ◽

Dopamine Neurons ◽

Dopamine Depletion ◽

Wild Type ◽

Disease Modifying Therapy ◽

Immortalized Cells ◽

Midbrain Dopamine ◽

6 Hydroxydopamine

Background: Parkinson’s disease (PD) is a progressive neurological disorder where loss of dopamine neurons in the substantia nigra and dopamine depletion in the striatum cause characteristic motor symptoms. Currently, no treatment is able to halt the progression of PD. Glial cell line-derived neurotrophic factor (GDNF) rescues degenerating dopamine neurons both in vitro and in animal models of PD. When tested in PD patients, however, the outcomes from intracranial GDNF infusion paradigms have been inconclusive, mainly due to poor pharmacokinetic properties. Objective: We have developed drug-like small molecules, named BT compounds that activate signaling through GDNF’s receptor, the transmembrane receptor tyrosine kinase RET, both in vitro and in vivo and are able to penetrate through the blood-brain barrier. Here we evaluated the properties of BT44, a second generation RET agonist, in immortalized cells, dopamine neurons and rat 6-hydroxydopamine model of PD. Methods: We used biochemical, immunohistochemical and behavioral methods to evaluate the effects of BT44 on dopamine system in vitro and in vivo. Results: BT44 selectively activated RET and intracellular pro-survival AKT and MAPK signaling pathways in immortalized cells. In primary midbrain dopamine neurons cultured in serum-deprived conditions, BT44 promoted the survival of the neurons derived from wild-type, but not from RET knockout mice. BT44 also protected cultured wild-type dopamine neurons from MPP +-induced toxicity. In a rat 6-hydroxydopamine model of PD, BT44 reduced motor imbalance and could have protected dopaminergic fibers in the striatum. Conclusion: BT44 holds potential for further development into a novel, possibly disease-modifying therapy for PD.

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The double-stranded DNA-binding proteins TEBP-1 and TEBP-2 form a telomeric complex with POT-1

Nature Communications ◽

10.1038/s41467-021-22861-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Sabrina Dietz ◽

Miguel Vasconcelos Almeida ◽

Emily Nischwitz ◽

Jan Schreier ◽

Nikenza Viceconte ◽

...

Keyword(s):

Quantitative Proteomics ◽

Wild Type ◽

C Elegans ◽

Double Stranded Dna ◽

Telomere Sequence ◽

Proteomics Approach ◽

Telomeric Protein ◽

Regulate Telomere Length

AbstractTelomeres are bound by dedicated proteins, which protect them from DNA damage and regulate telomere length homeostasis. In the nematode Caenorhabditis elegans, a comprehensive understanding of the proteins interacting with the telomere sequence is lacking. Here, we harnessed a quantitative proteomics approach to identify TEBP-1 and TEBP-2, two paralogs expressed in the germline and embryogenesis that associate to telomeres in vitro and in vivo. tebp-1 and tebp-2 mutants display strikingly distinct phenotypes: tebp-1 mutants have longer telomeres than wild-type animals, while tebp-2 mutants display shorter telomeres and a Mortal Germline. Notably, tebp-1;tebp-2 double mutant animals have synthetic sterility, with germlines showing signs of severe mitotic and meiotic arrest. Furthermore, we show that POT-1 forms a telomeric complex with TEBP-1 and TEBP-2, which bridges TEBP-1/-2 with POT-2/MRT-1. These results provide insights into the composition and organization of a telomeric protein complex in C. elegans.

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Development of a gel dedicated to gel immersion endoscopy

Endoscopy International Open ◽

10.1055/a-1396-4236 ◽

2021 ◽

Vol 09 (06) ◽

pp. E918-E924

Author(s):

Tomonori Yano ◽

Atsushi Ohata ◽

Yuji Hiraki ◽

Makoto Tanaka ◽

Satoshi Shinozaki ◽

...

Keyword(s):

Electrical Conductivity ◽

Porcine Model ◽

Ex Vivo ◽

In Vitro Experiments ◽

Efficacy And Safety ◽

Coagulative Necrosis ◽

Novel Technique ◽

In Vivo Experiments

Abstract Backgrounds and study aims Gel immersion endoscopy is a novel technique to secure the visual field during endoscopy. The aim of this study was to develop a dedicated gel for this technique. Methods To identify appropriate viscoelasticity and electrical conductivity, various gels were examined. Based on these results, the dedicated gel “OPF-203” was developed. Efficacy and safety of OPF-203 were evaluated in a porcine model. Results In vitro experiments showed that a viscosity of 230 to 1900 mPa·s, loss tangent (tanδ) ≤ 0.6, and hardness of 240 to 540 N/cm2 were suitable. Ex vivo experiments showed electrical conductivity ≤ 220 μS/cm is appropriate. In vivo experiments using gastrointestinal bleeding showed that OPF-203 provided clear visualization compared to water. After electrocoagulation of gastric mucosa in OPF-203, severe coagulative necrosis was not observed in the muscularis but limited to the mucosa. Conclusions OPF-203 is useful for gel immersion endoscopy.

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Study on Establishing Reference Safe Concentrations of MRI Contrast Agents for Optimized Images: Paramagnetic Gd-DTPA-BMEA and Superparamagnetic Ferucarbotran

Applied Sciences ◽

10.3390/app11031165 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1165

Author(s):

Wen-Tien Hsiao ◽

Yi-Hong Chou ◽

Jhong-Wei Tu ◽

Ai-Yih Wang ◽

Lu-Han Lai

Keyword(s):

Contrast Agent ◽

Contrast Agents ◽

Mri Contrast Agents ◽

Mri Contrast Agent ◽

In Vitro Experiments ◽

Mri Contrast ◽

In Vivo Experiments ◽

Contrast Agent Injection

The purpose of this study is to establish the minimal injection doses of magnetic resonance imaging (MRI) contrast agents that can achieve optimized images while improving the safety of injectable MRI drugs. Gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) and ferucarbotran, commonly used in clinical practice, were selected and evaluated with in vitro and in vivo experiments. MRI was acquired using T1-weighted (T1W) and T2-weighted (T2W) sequences, and the results were quantitatively analyzed. For in vitro experiments, results showed that T1W and T2W images were optimal when Gd-DTPA-bisamide (2-oxoethyl) (Gd-DTPA-BMEA) and ferucarbotran were diluted to a volume percentage of 0.6% and 0.05%; all comparisons were significant differences in grayscale statistics using one-way analysis of variance (ANOVA). For in vivo experiments, the contrast agent with optimal concentration percentages determined from in vitro experiments were injected into mice with an injection volume of 100 μL, and the images of brain, heart, liver, and mesentery before and after injection were compared. The statistical results showed that the p values of both T1W and T2W were less than 0.001, which were statistically significant. Under safety considerations for MRI contrast agent injection, optimized MRI images could still be obtained after reducing the injection concentration, which can provide a reference for the safety concentrations of MRI contrast agent injection in the future.

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Brown Spiders’ Phospholipases-D with Potential Therapeutic Applications: Functional Assessment of Mutant Isoforms

Biomedicines ◽

10.3390/biomedicines9030320 ◽

2021 ◽

Vol 9 (3) ◽

pp. 320

Author(s):

Thaís Pereira da Silva ◽

Fernando Jacomini de Castro ◽

Larissa Vuitika ◽

Nayanne Louise Costacurta Polli ◽

Bruno César Antunes ◽

...

Keyword(s):

Structural Changes ◽

Capillary Permeability ◽

Structural Data ◽

Histopathological Analysis ◽

Amino Acid Residues ◽

Wild Type ◽

Antigenic Properties ◽

Harmful Effects

Phospholipases-D (PLDs) found in Loxosceles spiders’ venoms are responsible for the dermonecrosis triggered by envenomation. PLDs can also induce other local and systemic effects, such as massive inflammatory response, edema, and hemolysis. Recombinant PLDs reproduce all of the deleterious effects induced by Loxosceles whole venoms. Herein, wild type and mutant PLDs of two species involved in accidents—L. gaucho and L. laeta—were recombinantly expressed and characterized. The mutations are related to amino acid residues relevant for catalysis (H12-H47), magnesium ion coordination (E32-D34) and binding to phospholipid substrates (Y228 and Y228-Y229-W230). Circular dichroism and structural data demonstrated that the mutant isoforms did not undergo significant structural changes. Immunoassays showed that mutant PLDs exhibit conserved epitopes and kept their antigenic properties despite the mutations. Both in vitro (sphingomyelinase activity and hemolysis) and in vivo (capillary permeability, dermonecrotic activity, and histopathological analysis) assays showed that the PLDs with mutations H12-H47, E32-D34, and Y228-Y229-W230 displayed only residual activities. Results indicate that these mutant toxins are suitable for use as antigens to obtain neutralizing antisera with enhanced properties since they will be based on the most deleterious toxins in the venom and without causing severe harmful effects to the animals in which these sera are produced.

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