scholarly journals Role of Iron(III)-salen Chloride as Oxidizing Agent with Thiodiglycolic Acid: The Effect of Axial Ligands

2017 ◽  
Vol 58 (2) ◽  
Author(s):  
Perumal Subramaniam ◽  
Thangadurai Vanitha ◽  
Thiruttimuthu Kodispathi ◽  
Chandra Raj Shanmuga Sundari
Keyword(s):  
Reaction Rate ◽  
Oxidizing Agent ◽  
Aqueous Acetonitrile ◽  
Nitrogen Bases ◽  
Thiodiglycolic Acid ◽  
Axial Ligands ◽  
Retarding Effect ◽  
Highly Sensitive ◽  
Acetonitrile Medium

The sulfoxidation of thiodiglycolic acid with iron(III)-salen chloride, which acts as an oxidizing agent without any terminal oxidant, in 50% aqueous acetonitrile medium has been studied. A substantial red shift in the λ<sub>max</sub>value of FeIII-salen was observed in aqueous medium. The spectrophotometric kinetic study indicates that [Fe<sup>III</sup>(salen)]+ is the active oxidizing species and the reaction follows Michaelis-Menten kinetics with respect to the substrate. The rate of the reaction is highly sensitive to the medium. A reaction mechanism involving electron transfer from sulfur atom of thiodiglycolic acid to the central iron atom of [Fe<sup>III</sup>(salen)]<sup>+</sup> is proposed. The presence of nitrogenous bases like pyridine, imidazole and 1-methylimidazole shows a retarding effect on the reaction rate. This can be explained on the basis of binding of these ligands to the coordination sphere of [Fe<sup>III</sup>(salen)]<sup>+</sup> prior to the reaction with the substrate. The observed order of reactivity, pyridine &gt; 1-methylimidazole &gt; imidazole, is in accordance with the inverse of <em>π</em>-donating ability of nitrogen bases.

scholarly journals A mechanistic investigation of the oxidation of N,α-diphenylnitrones by dichloramine-T in aqueous acetonitrile medium - a non-linear Hammett plot

2009 ◽  
Vol 74 (5) ◽  
pp. 493-502
Author(s):  
S. Manivarman ◽  
G. Rajarajan ◽  
G. Manikandan ◽  
M. Sekar ◽  
J. Jayabharathi ◽  
...  
Keyword(s):  
Reaction Rate ◽  
The Other ◽  
Hammett Constant ◽  
Kinetics Of Oxidation ◽  
Aqueous Acetonitrile ◽  
First Order ◽  
Mechanistic Investigation ◽  
Non Linear ◽  
Kinetics Of ◽  
Acetonitrile Medium

The kinetics of oxidation of a number of meta- and para-substituted N,?-diphenylnitrones (nitrone) by dichloramine-T (DCT) was investigated in the presence of alkali in aqueous acetonitrile medium. The order with respect to DCT was one and to OH- an inverse fractional order. The reaction was first order with respect to nitrone. Both electron releasing and withdrawing substituents suppress the reaction rate. The observed rate constant for the substituents were plotted against the Hammett constant, ?, and a non-linear concave downward curve was obtained. The electron withdrawing substituents fall on one side of the curve, having a negative ? value and the electron releasing substituents fall on the other side, with a positive ? value. A mechanism is proposed and the derived rate law is in conformity with the observed results.

Highly sensitive adolescent benefits in positive school transitions: Evidence for vantage sensitivity in Japanese high-schoolers

2020 ◽  
Author(s):  
Shuhei Iimura
Keyword(s):  
High School ◽  
Statistical Power ◽  
Environmental Influences ◽  
Differential Susceptibility ◽  
School Transition ◽  
Well Being ◽  
Crossover Point ◽  
Japanese Adolescents ◽  
Highly Sensitive

Some researchers indicate that the transition to high school deflects adolescent developmental trajectories. Others assert it provides a new possibility for the promotion of adolescents’ socioemotional well-being. One critical view missing in such claims is that individual variabilities interact with environmental influences. We employed the framework of Differential Susceptibility Theory, which postulates that individual susceptibilities moderate external influences for better and for worse. In order to clarify the mechanism of adolescents’ differential adjustments, this paper investigated the role of sensory-processing sensitivity using the Japanese version of Highly Sensitive Child Scale for Adolescence (J-HSCS), and tested whether the diathesis-stress model or the differential susceptibility model best describes students’ socioemotional adjustment across their high school transition. The current paper used the two-wave data collected from Japanese adolescents aged from 14 to 15 years (n = 412, 50% girls). In Study 1, we investigated the replicability of psychometric properties of J-HSCS. The results supported previous findings, indicating its validity for the bifactor model. In Study 2, we utilized confirmatory competitive model testing, which maximizes statistical power by parameterizing the crossover point to allow a direct comparison of alternative models. The results indicated that neither the diathesis-stress nor the differential susceptibility models fitted the data. Rather, a strong vantage sensitivity model was revealed, suggesting that highly susceptible adolescents disproportionately benefitted from a positive school transition over their counterparts. This finding signified the role of adolescents’ sensitivity to environmental influences and the importance of considering its moderation under person x environment interactions.

scholarly journals Role of MRI evaluation in acute secondary inability to walk in children

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
K. H. Sedeek ◽  
K. Aboualfotouh ◽  
S. M. Hassanein ◽  
N. M. Osman ◽  
M. H. Shalaby
Keyword(s):  
Transverse Myelitis ◽  
High Sensitivity ◽  
Acute Disseminated Encephalomyelitis ◽  
Limb Weakness ◽  
Non Invasive ◽  
Highly Sensitive ◽  
Common Causes ◽  
Bilateral Lower Limb ◽  
Severity Of The Disease

Abstract Background Acute bilateral lower limb weakness is a common problem in children which necessitates a rapid method for diagnosis. MRI is a non-invasive imaging technique that produces high-quality images of the internal structure of the brain and spinal cord. Results MRI was very helpful in reaching rapid and prompt diagnosis in children with acute inability to walk. Acute disseminated encephalomyelitis (ADEM), Guillain–Barré syndrome (GBS), and acute transverse myelitis (ATM) were the most common causes in our study. MRI proved to be of high sensitivity in detecting the lesions and reaching the diagnosis in ADEM and GBS; however, there was no significant relation between the lesions’ size, enhancement pattern, and severity of the disease or prognosis, yet in ATM the site of the lesion and number of cord segment affection were significantly related to the severity of the disease and prognosis. Conclusion MRI is a quick tool to reach the diagnosis of children with acute secondary inability to walk, and to eliminate other differential diagnosis which is essential for proper treatment and rapid full recovery. It is highly sensitive in detecting the lesions, their site and size.

scholarly journals Interphotoreceptor coupling: an evolutionary perspective

2021 ◽  
Author(s):  
Lorenzo Cangiano ◽  
Sabrina Asteriti
Keyword(s):  
Visual Information ◽  
Signal To Noise Ratio ◽  
Electrical Coupling ◽  
Physiological Role ◽  
Cellular Processes ◽  
Contact Points ◽  
Highly Sensitive ◽  
The Many ◽  
The Impact

AbstractIn the vertebrate retina, signals generated by cones of different spectral preference and by highly sensitive rod photoreceptors interact at various levels to extract salient visual information. The first opportunity for such interaction is offered by electrical coupling of the photoreceptors themselves, which is mediated by gap junctions located at the contact points of specialised cellular processes: synaptic terminals, telodendria and radial fins. Here, we examine the evolutionary pressures for and against interphotoreceptor coupling, which are likely to have shaped how coupling is deployed in different species. The impact of coupling on signal to noise ratio, spatial acuity, contrast sensitivity, absolute and increment threshold, retinal signal flow and colour discrimination is discussed while emphasising available data from a variety of vertebrate models spanning from lampreys to primates. We highlight the many gaps in our knowledge, persisting discrepancies in the literature, as well as some major unanswered questions on the actual extent and physiological role of cone-cone, rod-cone and rod-rod communication. Lastly, we point toward limited but intriguing evidence suggestive of the ancestral form of coupling among ciliary photoreceptors.

scholarly journals DNAJB6b is Downregulated in Synucleinopathies

2021 ◽  
pp. 1-13
Author(s):  
Jonas Folke ◽  
Sertan Arkan ◽  
Isak Martinsson ◽  
Susana Aznar ◽  
Gunnar Gouras ◽  
...  
Keyword(s):  
Neurodegenerative Diseases ◽  
Substantia Nigra Pars Compacta ◽  
Endogenous Protein ◽  
Highly Sensitive ◽  
Brain Material ◽  
Health And Disease ◽  
Isoform B

Background: α-synuclein (α-syn) aggregation contributes to the progression of multiple neurodegenerative diseases. We recently found that the isoform b of the co-chaperone DNAJB6 is a strong suppressor of a-syn aggregation in vivo and in vitro. However, nothing is known about the role of the endogenous isoform b of DNAJB6 (DNAJB6b) in health and disease, due to lack of specific antibodies. Objective: Here we generated a novel anti-DNAJB6b antibody to analyze the localization and expression this isoform in cells, in tissue and in clinical material. Methods: To address this we used immunocytochemistry, immunohistochemistry, as well as a novel quantitative DNAJB6 specific ELISA method. Results: The endogenous protein is mainly expressed in the cytoplasm and in neurites in vitro, where it is found more in dendrites than in axons. We further verified in vivo that DNAJB6b is expressed in the dopaminergic neurons of the substantia nigra pars compacta (SNpc), which is a neuronal subpopulation highly sensitive to α-syn aggregation, that degenerate to a large extend in patients with Parkinson’s disease (PD) and multiple system atrophy (MSA). When we analyzed the expression levels of DNAJB6b in brain material from PD and MSA patients, we found a downregulation of DNAJB6b by use of ELISA based quantification. Interestingly, this was also true when analyzing tissue from patients with progressive supranuclear palsy, a taupathic atypical parkinsonian disorder. However, the total level of DNAJB6 was upregulated in these three diseases, which may indicate an upregulation of the other major isoform of DNAJB6, DNAJB6a. Conclusion: This study shows that DNAJB6b is downregulated in several different neurodegenerative diseases, which makes it an interesting target to further investigate in relation to amyloid protein aggregation and disease progression.

Role of laparoscopic in diagnosis and treatment of undescended testis in children at Viet Duc Hospital

2018 ◽  
Vol 8 (4) ◽  
Author(s):  
Viet Hoa Nguyen
Keyword(s):  
Laparoscopic Surgery ◽  
Undescended Testis ◽  
Correct Diagnosis ◽  
Diagnosis And Treatment ◽  
Highly Sensitive ◽  
The Mean ◽  
The Right ◽  
Time Of Operation

Abstract Introduction: Evaluating the role of laparoscopic for diagnosis and treatment of undescended testis in children. Material and Methods: Restrospective study, between 6/ 2014 and 6/2017. All the patients are aged from 1 to 16 years with undescended testis underwent laparoscopic surgery for diagnosis and treatment in Deparment of pediatric surgery – Viet Duc hospital enrolled. Results: Of 95 patiens in total had 106 undescended testis diagnosed and treated by laparoscopy. The mean age of patients was 7,5 ± 3,8 years. 44,2% undescended were on the left side, 44,2% were on the right and 11,6% were undescended bilateral. The correct diagnosis by ultrasound accounted in 79,4%. The locations of testis diagnosed by laparoscopic are : intra abdomen in 45,3%, deep inguinal orifice in 16,9%, extra inguinal orifice in 26,4%, no testicle found in 11,4%. The mean time of operation were 67,33± 28,01 pht. Scrotal positions were achieved 74,5%, remove atrophic testis accounted in 7,6%. Stephen- Flowler technique including step I were in 4,7%, step II in 1,9%. The outcome evaluated by testicular positions following 3 months after operation are : good in 79,2%, moderate 13,2%, poor in 7,6%; By classification of Aubert are : good in 81,1%, moderate in 11,3% and poor in 7,6 %. Conclusion: Laparoscopic surgery is not only a highly sensitive diagnostic method to find accurately the location and size of the testes, but also the most effective method to treat impalpable undescended testes.

The role of the skin in rabies infection

1926 ◽  
Vol 22 (10) ◽  
pp. 1179-1179
Author(s):  
K. Khalyapin
Keyword(s):  
Virus Infection ◽  
Guinea Pig ◽  
Rabies Virus ◽  
Anatomical Features ◽  
Pig Skin ◽  
Highly Sensitive ◽  
Rabies Virus Infection

The author verified by experiment that the guinea pig skin is an organ highly sensitive to the rabies virus - infection with rabies through the skin is very easy, which the author puts in connection with its anatomical features (a rich network of nerves).

The Right to Freedom of Thought in the United Kingdom

2021 ◽  
pp. 1-25
Author(s):  
Frank Cranmer
Keyword(s):  
United Kingdom ◽  
Political Debate ◽  
The United Kingdom ◽  
Repeated Calls ◽  
Highly Sensitive ◽  
Domestic Legislation ◽  
International Obligations ◽  
Freedom Of Thought ◽  
The Right

Abstract The United Kingdom is bound by international obligations to uphold ‘the right to freedom of thought, conscience and religion’ and domestic legislation reflects those obligations. The courts have held that to be protected, a belief must genuine, must not be a mere opinion, must attain a certain level of cogency, seriousness and importance and must be ‘worthy of respect in a democratic society’. How this plays out, however, in areas such as education, children’s rights and employment is highly sensitive to the specific facts of each case – which are often inconsistent, as the article explains. Much of the article examines the decisions of the courts in individual cases. It concludes with a discussion of the possible trajectory of domestic political debate at a time when there have been repeated calls for a ‘British Bill of Rights’ and the Westminster Government is questioning more generally the constitutional role of the judiciary.

The Role of Equatorial and Axial Ligands in Promoting the Activity of Non-Heme Oxidoiron(IV) Catalysts in Alkane Hydroxylation

2007 ◽  
Vol 2007 (19) ◽  
pp. 3023-3033 ◽  
Author(s):  
Leonardo Bernasconi ◽  
Manuel J. Louwerse ◽  
Evert Jan Baerends
Keyword(s):  
Axial Ligands ◽  
Alkane Hydroxylation

scholarly journals PGRMC1-dependent lipophagy promotes ferroptosis in paclitaxel-tolerant persister cancer cells

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Ji Hyeon You ◽  
Jaewang Lee ◽  
Jong-Lyel Roh
Keyword(s):  
Cancer Cells ◽  
Lipid Droplets ◽  
Tumor Xenograft ◽  
Acid Oxidation ◽  
Mouse Tumor ◽  
Autophagy Induction ◽  
Highly Sensitive ◽  
Xenograft Models

Abstract Background Progesterone receptor membrane component 1 (PGRMC1) is a heme-binding protein inducing dimerization with cytochrome P450, which mediates chemoresistance. Increased PGRMC1 expression is found in multiple types of resistant cancers, but the role of PGRMC1 in the ferroptosis of cancer cells remains unrevealed. Therefore, we examined the role of PGRMC1 in promoting ferroptosis in paclitaxel-tolerant persister cancer cells (PCC). Methods The effects of ferroptosis inducers and PGRMC1 gene silencing/overexpression were tested on head and neck cancer (HNC) cell lines and mouse tumor xenograft models. The results were analyzed about cell viability, death, lipid ROS and iron production, mRNA/protein expression and interaction, and lipid assays. Results PCC had more free fatty acids, lipid droplets, and fatty acid oxidation (FAO) than their parental cells. PCC was highly sensitive to inhibitors of system xc− cystine/glutamate antiporter (xCT), such as erastin, sulfasalazine, and cyst(e)ine deprivation, but less sensitive to (1S,3R)-RSL3. PGRMC1 silencing in PCC reduced ferroptosis sensitivity by xCT inhibitors, and PGRMC1 overexpression in parental cells increased ferroptosis by xCT inhibitors. Lipid droplets were degraded along with autophagy induction and autophagosome formation by erastin treatment in PCC. Lipophagy was accompanied by increased tubulin detyrosination, which was increased by SIRT1 activation but decreased by SIRT1 inhibition. FAO and lipophagy were also promoted by the interaction between lipid droplets and mitochondria. Conclusion PGRMC1 expression increased FAO and ferroptosis sensitivity from in vivo mice experiments. Our data suggest that PGRMC1 promotes ferroptosis by xCT inhibition in PCC.

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