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1.
Mol Microbiol ; 116(1): 29-40, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33706420

RESUMO

How anaerobic bacteria protect themselves against nitric oxide-induced stress is controversial, not least because far higher levels of stress were used in the experiments on which most of the literature is based than bacteria experience in their natural environments. This results in chemical damage to enzymes that inactivates their physiological function. This review illustrates how transcription control mechanisms reveal physiological roles of the encoded gene products. Evidence that the hybrid cluster protein, Hcp, is a major high affinity NO reductase in anaerobic bacteria is reviewed: if so, its trans-nitrosation activity is a nonspecific secondary consequence of chemical inactivation. Whether the flavorubredoxin, NorV, is equally effective at such low [NO] is unknown. YtfE is proposed to be an enzyme rather than a source of iron for the repair of iron-sulfur proteins damaged by nitrosative stress. Any reaction catalyzed by YtfE needs to be revealed. The concentration of NO that accumulates in the cytoplasm of anaerobic bacteria is unknown, but indirect evidence indicates that it is in the pM to low nM range. Also unknown are the functions of the NO-inducible cytoplasmic proteins YgbA, YeaR, or YoaG. Experiments to resolve some of these questions are proposed.


Assuntos
Bactérias Anaeróbias/metabolismo , Óxido Nítrico/metabolismo , Estresse Nitrosativo/fisiologia , Oxirredutases/metabolismo , Anaerobiose/fisiologia , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Transcrição Gênica/genética
2.
Mol Genet Genomics ; 292(6): 1419-1430, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28836000

RESUMO

Ancient DNA obtained from ancient samples, such as sediments, bones, and teeth, is an important genetic resource that can be used to reconstruct an evolutional history of humans, animals, and plants. The application of high-throughput sequencing enables the research of ancient DNA to be conducted in a whole genome scale. However, post-mortem DNA damage mainly caused by deamination of cytosine to uracil (or methylated cytosine to thymine) may confound the variant calling and downstream analysis. In this article, we develop a Python program to implement a new variant caller, "AntCaller", which extracts the information on nucleotide substitutions from sequencing data and calculates the probability of each genotype based on a Bayesian rule. Through both simulation studies and real data analyses, it was shown that our method reduced the false discovery rate caused by nucleotide misincorporations and outperformed two mainstream variant callers (i.e., GATK and SAMtools) in terms of calling accuracy. In a real application with serious DNA damage, AntCaller still outperformed GATK and SAMtools combined with quality score recalling.


Assuntos
Dano ao DNA , DNA Antigo , Animais , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Homem de Neandertal , Ploidias , Mudanças Depois da Morte
3.
Br J Nurs ; 25(19): S28-S33, 2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27792444

RESUMO

Intravenous (IV) infusions are an essential part of hospital patient care, but occlusions in peripheral cannulae are common. One of the most dangerous consequences of occlusion (blockage) is extravasation-the non-intentional leakage of infused vesicant fluid into the tissue surrounding the vein-as it can lead to long-term, or even permanent, tissue damage. Adults and children are affected, with preterm neonates being particularly vulnerable. In-line pressure monitoring (ILPM) can help identify occlusions early and help prevent complications such as extravasation and infiltration. Occlusions cause a rise in pressure in the IV line, so IV pumps fitted with ILPM are able to detect this rise in pressure early and sound an alarm, allowing the user to take corrective measures before the patient suffers any serious chemical damage. ILPM also helps prevent or minimise other consequences of in-line occlusions such as suboptimal medicine dosing, patient distress, and economic costs to NHS trusts.


Assuntos
Extravasamento de Materiais Terapêuticos e Diagnósticos/prevenção & controle , Bombas de Infusão , Infusões Intravenosas/enfermagem , Pressão , Obstrução do Cateter/efeitos adversos , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Humanos
4.
Ann Transl Med ; 10(17): 927, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36172099

RESUMO

Background: Traumatic spinal cord injury (SCI) is a major clinical concern and a life-changing neurological condition with substantial socioeconomic implications. The initial mechanical force applied to the spinal cord at the time of injury is known as the primary injury. After the primary injury, ischemia and hypoxia induce cell death and autolysis, which are associated with the release of a group of inflammatory factors and biologically active substances, such as superoxide dismutase (SOD), malonaldehyde (MDA), lactate dehydrogenase (LDH), and tumor necrosis factor-α (TNF-α). These processes are called the secondary injury, and may lead to an excess of extracellular glutamate (Glu), which in turn promotes the neuronal injuries. Muscone has been shown to have anti-inflammatory effects in the treatment of brain diseases and other diseases. However, to date, no study has examined the effects of muscone in the treatment of SCI. Methods: Astrocytes were separated and purified by the method of short-term exposure combining with differential sticking wall. Astrocyte was identified by glial fibers acidic protein (GFAP) selecting cell immunochemical staining. A mechanical-chemical damage (MCD) model was established via the primary spinal astrocytes of rats, and treatment was administered with different concentrations of muscone. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) was detected at 6, 12, 24, 48 and 72 h. SOD, MDA, LDH, TNF-alpha and intracellular calcium was detected at 3, 6 and 12 h. Glu in supernatant was detected respectively at 3, 6 and 12 h by enzyme-linked immunosorbent assay (ELISA) method. Intracellular calcium was detected respectively at 3, 6 and 12 h by flow cytometry method. MRNA expression of excitatory amino acid transporters (EAATs) and GFAP were detected by the quantitative reverse transcription polymerase chain reaction (qRT-PCR) method and protein expression of those by western blot at 6 h. Results: Muscone reduced the levels of LDH, TNF-α, and MDA after injury, and upregulated the level of SOD. Muscone also reduced the density of extracellular Glu and suppressed the intracellular calcium level. Additionally, it decreased the expression levels of EAATs and GFAPs. Conclusions: Muscone has a protective effect on astrocytes in a MCD and inhibits astrocytes' proliferation.

5.
J Nutr Biochem ; 107: 109069, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35609849

RESUMO

Several studies have shown the beneficial effect that Epicatechin (Epi) has on the skeletal muscle of murine models and patients with muscular dystrophy and in the muscles of patients with diabetes or murine sarcopenia models. This flavanol has been shown to enhance antioxidant pathways and improve muscle architecture. However, the repair process during muscle regeneration has not been analyzed. To address this, we characterize the effect of Epi in the repair process of the Tibialis anterior in a murine model with BaCl2-induced damage. CD1 mice of 10 weeks of age were randomly selected and injured with BaCl2. One hour later, they were divided into four groups (n=6 for histology groups and n=12 for western blot groups). Epi was administered every 12h, until the time of sacrifice. Histological and morphological analysis showed that Epi significantly reduced the area of damage and hypertrophy at 15 days in the damaged muscle. Furthermore, western blot assays showed that the treatment increases ß-catenin (active) and myogenic proteins such as MyoD and Myogenin. These results show that Epi exerts therapeutic effects accelerating skeletal muscle repair after induced damage chemically, thus highlighting the therapeutic potential of this flavanol in different myopathies.


Assuntos
Catequina , Sarcopenia , Animais , Catequina/metabolismo , Catequina/farmacologia , Camundongos , Desenvolvimento Muscular , Músculo Esquelético/metabolismo , Regeneração , Sarcopenia/metabolismo
6.
ACS Appl Mater Interfaces ; 11(32): 29388-29395, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31313569

RESUMO

Self-healability is a crucial feature for developing artificial superhydrophobic surfaces. Although self-healing of microscopic defects has been reported, the restoration of severely damaged superhydrophobic surfaces remains a technological challenge. Here, we report a robust superhydrophobic surface possessing ultrafast recoverability after catastrophic damage. The surface is fabricated via integrating its hierarchical texture comprised of Super P (a conductive carbon black) and TiO2 nanoparticles into a poly(dimethylsiloxane) network cross-linked by dynamic pyrogallol-Fe coordination. In the presence of an electrical trigger, the surface restores its macroscopic configuration, hierarchical texture, mechanical properties, and wettability within 1 min after being cut or plasma etching. The restoration is attributed to the reconstruction of the multiscale structures through dynamic coordination. Application of the self-healable surface is demonstrated by a fast de-icing process. The present investigation offers a novel insight into the durability and reliability of artificial superhydrophobic surfaces against catastrophic damage, which has potential application in the fields including self-cleaning, anti-icing, advanced electronics, and so on.

7.
Skin Appendage Disord ; 1(2): 99-104, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27170942

RESUMO

Dermoscopy represents a useful technique for the diagnosis and follow-up of hair and scalp disorders. To date, little has been published regarding dermoscopy findings of hair disorders in patients of African descent. This article illustrates how dermoscopy allows fast diagnosis of hair breakage due to intrinsic factors and chemical damage in African descent patients.

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