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1.
Nat Mater ; 22(1): 36-41, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36396962

RESUMO

The honeycomb magnet α-RuCl3 has attracted considerable interest because it is proximate to the Kitaev Hamiltonian whose excitations are Majoranas and vortices. The thermal Hall conductivity κxy of Majorana fermions is predicted to be half-quantized. Half-quantization of κxy/T (T, temperature) was recently reported, but this observation has proven difficult to reproduce. Here, we report detailed measurements of κxy on α-RuCl3 with the magnetic field B ∥ a (zigzag axis). In our experiment, κxy/T is observed to be strongly temperature dependent between 0.5 and 10 K. We show that its temperature profile matches the distinct form expected for topological bosonic modes in a Chern-insulator-like model. Our analysis yields magnon band energies in agreement with spectroscopic experiments. At high B, the spin excitations evolve into magnon-like modes with a Chern number of ~1. The bosonic character is incompatible with half-quantization of κxy/T.

2.
Langmuir ; 40(10): 5314-5325, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38408899

RESUMO

Zwitterionic polymers are an emerging family of effective, low-fouling materials that can withstand unintended interactions with biological systems while exhibiting enhanced activity in bacterial matrix deterioration and biofilm eradication. Herein, we modularly synthesized an amphiphilic block copolymer, ZABCP, featuring potential bacteriostatic properties composed of a charge-switchable polyzwitterionic segment and a redox-sensitive pendant disulfide-labeled polymethacrylate block. The leucine-appended polyzwitterionic segment with alternatively positioned cationic amine and anionic carboxylate functionalities undergoes charge alterations (+ve → 0 → -ve) on pH variation. By introducing appropriate amphiphilicity, ZABCP forms distinct vesicles with redox-sensitive bilayer membranes and zwitterionic shielding coronas, enabling switching of surface charge. ZABCP vesicles exhibit 180 ± 20 nm hydrodynamic diameter, and its charge switching behavior in response to pH was confirmed by the change of zeta potential value from -23 to +36 mV. The binding interaction between ZABCP vesicles with lysozyme and pepsin proteins strengthens when the surface charge shifts from neutral (pH 7.4) to either anionic or cationic. This surface-charge-switchable phenomenon paves the way for implementing cationic ZABCP vesicles for bacterial cell growth inhibition, which is shown by the pronounced transition of cellular morphology, including clustering, aggregation, or elongation as well as membrane disruption for both Bacillus subtilis (Gram-positive) and Escherichia coli (Gram-negative). Such enhanced bacteriostatic activity could be ascribed to a strong electrostatic interaction between cationic vesicles and negatively charged bacterial membranes, leading to cell membrane disruption. Overall, this study provides a tailor-made approach to adopt low-fouling properties and potential bacteriostatic activity using zwitterionic polymers through precise control of pH.


Assuntos
Incrustação Biológica , Incrustação Biológica/prevenção & controle , Proteínas/metabolismo , Cátions/química , Membrana Celular/metabolismo , Polímeros/química , Propriedades de Superfície
3.
Mol Biol Rep ; 51(1): 277, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319443

RESUMO

BACKGROUND: The most widely used food additive monosodium glutamate (MSG) has been linked to immunopathology. Conversely, quercetin (Q), a naturally occurring flavonoid has been demonstrated to have immunomodulatory functions. Therefore, the purpose of the study is to determine if quercetin can mitigate the deleterious effects of MSG on immune cells, and the possible involvement of TLR, if any.  METHODS AND RESULTS: This study was conducted on Q, to determine how it affects the inflammatory response triggered by MSG in primary cultured thymocytes and splenocytes from rats (n = 5). Q shielded cells by augmenting cell survival and decreasing lactate dehydrogenase leakage during MSG treatment. It decreased IL-1ß, IL-6, IL-8, and TNF-α expression and release by hindering NF-kB activation and by inhibiting the JAK/STAT pathway. Moreover, Q prevented NLRP3 activation, lowered IL-1ß production, and promoted an anti-inflammatory response by increasing IL-10 production. Q reduced MSG-induced cellular stress and inflammation by acting as an agonist for PPAR-γ and LXRα, preventing NF-kB activation, and lowering MMP-9 production via increasing TIMP-1. Additionally, Q neutralized free radicals, elevated intracellular antioxidants, and impeded RIPK3, which is involved in inflammation induced by oxidative stress, TNF-α, and TLR agonists in MSG-treated cells. Furthermore, it also modulated TYK2 and the JAK/STAT pathway, which exhibited an anti-inflammatory effect. CONCLUSIONS: MSG exposure is associated with immune cell dysfunction, inflammation, and oxidative stress, and Q modulates TLR to inhibit NF-kB and JAK/STAT pathways, providing therapeutic potential. Further research is warranted to understand Q's downstream effects and explore its potential clinical applications in inflammation.


Assuntos
NF-kappa B , Transdução de Sinais , Animais , Ratos , Anti-Inflamatórios , Inflamação/induzido quimicamente , Janus Quinases , Quercetina/farmacologia , Glutamato de Sódio/toxicidade , Baço , Fatores de Transcrição STAT , Timócitos , Fator de Necrose Tumoral alfa
4.
Philos Trans A Math Phys Eng Sci ; 381(2241): 20210414, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36463920

RESUMO

Novel magnetic materials are important for future technological advances. Theoretical and numerical calculations of ground-state properties are essential in understanding these materials, however, computational complexity limits conventional methods for studying these states. Here we investigate an alternative approach to preparing materials ground states using the quantum approximate optimization algorithm (QAOA) on near-term quantum computers. We study classical Ising spin models on unit cells of square, Shastry-Sutherland and triangular lattices, with varying field amplitudes and couplings in the material Hamiltonian. We find relationships between the theoretical QAOA success probability and the structure of the ground state, indicating that only a modest number of measurements ([Formula: see text]) are needed to find the ground state of our nine-spin Hamiltonians, even for parameters leading to frustrated magnetism. We further demonstrate the approach in calculations on a trapped-ion quantum computer and succeed in recovering each ground state of the Shastry-Sutherland unit cell with probabilities close to ideal theoretical values. The results demonstrate the viability of QAOA for materials ground state preparation in the frustrated Ising limit, giving important first steps towards larger sizes and more complex Hamiltonians where quantum computational advantage may prove essential in developing a systematic understanding of novel materials. This article is part of the theme issue 'Quantum annealing and computation: challenges and perspectives'.

5.
J Enzyme Inhib Med Chem ; 38(1): 2276665, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919954

RESUMO

Structural tailoring of the flavone framework (position 7) via organopalladium-catalyzed C-C bond formation was attempted in this study. The impact of substituents with varied electronic effects (phenyl ring, position 2 of the benzopyran scaffold) on the antitumor properties was also assessed. Resultantly, the efforts yielded a furyl arm bearing benzopyran possessing a 4-fluoro phenyl ring (position 2) (14) that manifested a magnificent antitumor profile against the Ishikawa cell lines mediated through dual inhibition of PARP and tubulin [(IC50 (PARP1) = 74 nM, IC50 (PARP2) = 109 nM) and tubulin (IC50 = 1.4 µM)]. Further investigations confirmed the ability of 14 to induce apoptosis as well as autophagy and cause cell cycle arrest at the G2/M phase. Overall, the outcome of the study culminated in a tractable dual PARP-tubulin inhibitor endowed with an impressive activity profile against endometrial cancer.


Assuntos
Antineoplásicos , Neoplasias do Endométrio , Flavonas , Humanos , Feminino , Moduladores de Tubulina/farmacologia , Moduladores de Tubulina/química , Tubulina (Proteína)/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/patologia , Flavonas/farmacologia , Benzopiranos , Proliferação de Células
6.
Environ Monit Assess ; 195(10): 1250, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37758966

RESUMO

The present work was conducted in the forest-based ecosystem of Chhattisgarh in order to assess the varietal performance of coffee varieties along with silver oak in terms of growth, biomass, and carbon dynamics. Five coffee varieties were planted in silver oak shade in a randomized block design with four replications. The aim of the present investigation is to assess the economic and ecological feasibility of forest-based coffee plantations in the Bastar region of Chhattisgarh. Findings reflect the maximum under-storied plant height in Chandragiri Dwarf (1.85 m) which was at par with CxR (1.82 m) and San Ramon (1.71 m). The maximum above and below-ground carbon stock (48.40 and 12.09 Mg ha-1, respectively), as well as carbon dioxide (CO2) mitigation (177.63 and 44.41 Mg ha-1, respectively) from the under-storied coffee plantation, was recorded in CxR. In the upper-storied plantation, the above and below-ground biomass of silver oak recorded the maximum carbon stock (201.24 and 50.31 Mg ha-1, respectively) and CO2 mitigation (738.54 and 184.63 Mg ha-1) in S-8 intercropped lines. The highest value of carbon credit was recorded under the coffee variety S-8 and silver oak agroecosystem. The S-8, CxR, and Chandragiri Dwarf varieties performed quite well in terms of the expected value of carbon credit.


Assuntos
Dióxido de Carbono , Ecossistema , Biomassa , Prata , Monitoramento Ambiental , Florestas , Plantas , Índia , Árvores , Solo
7.
Aust J Rural Health ; 31(3): 464-470, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36745537

RESUMO

OBJECTIVE: Perioperative initiation of opioids continues to be a major contributor to chronic use, misuse and diversion in regional areas. There is considerable effort to mitigate harm through avoiding excessive prescribing and reducing the risk of persistent postoperative opioid use. Improving perioperative documentation practices has been reported to ensure appropriate opioid initiation and de-escalation. It has not been established whether these strategies are utilised in regional hospitals. METHODS: A retrospective observational study of perioperative opioid prescribing and documentation practices in Goulburn Base Hospital, a regional centre in the Southern New South Wales (NSW) Local Health District. Data were collected from 110 records and validated for adult patients undergoing elective total knee replacement (TKR) or total hip replacement (THR) from 12 January 2020 to 13 January 2021. OUTCOME MEASURES: To observe perioperative opioid prescribing and utilisation of harm reduction strategies in a regional hospital. RESULTS: 65% of patients were opioid naïve (ON). Preoperative pain assessments and patient education were completed in 23% and 15% of records, respectively. Postoperative opioids were prescribed for 99% of patients, with 74% prescribed a slow-release (SR) formulation. 50% of patients were discharged with an SR prescription. Inadequate postoperative pain control was reported in 21% of patients. Of the 103 patients prescribed opioids on discharge, only 20% included a de-escalation plan and only 35% of discharge summaries included dose and quantity of opioids supplies. CONCLUSIONS: This study has identified underutilisation of perioperative harm reduction strategies despite the potential to improve appropriate initiation and de-escalation of opioids. These findings highlight opportunities for improvement in regional hospitals.


Assuntos
Analgésicos Opioides , Redução do Dano , Adulto , Humanos , Analgésicos Opioides/uso terapêutico , New South Wales , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica , Estudos Retrospectivos
8.
Entropy (Basel) ; 25(3)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36981429

RESUMO

Recent advances in quantum hardware offer new approaches to solve various optimization problems that can be computationally expensive when classical algorithms are employed. We propose a hybrid quantum-classical algorithm to solve a dynamic asset allocation problem where a target return and a target risk metric (expected shortfall) are specified. We propose an iterative algorithm that treats the target return as a constraint in a Markowitz portfolio optimization model, and dynamically adjusts the target return to satisfy the targeted expected shortfall. The Markowitz optimization is formulated as a Quadratic Unconstrained Binary Optimization (QUBO) problem. The use of the expected shortfall risk metric enables the modeling of extreme market events. We compare the results from D-Wave's 2000Q and Advantage quantum annealers using real-world financial data. Both quantum annealers are able to generate portfolios with more than 80% of the return of the classical optimal solutions, while satisfying the expected shortfall. We observe that experiments on assets with higher correlations tend to perform better, which may help to design practical quantum applications in the near term.

9.
Amino Acids ; 54(8): 1135-1154, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35286462

RESUMO

GnRH-I and GnIH are the key neuropeptides that regulate the hypothalamic-pituitary-gonadal axis in mammals during aging. Polyamines are important aliphatic amines that are expressed in the brain and show variation with aging. The present study demonstrates evidence of variation in the level of expression of polyamines, GnRH-I and GnIH in the hypothalamus of female mice during aging. The study also suggests regulatory effects of polyamines over expression of the hypothalamic GnRH-I. The study shows a significant positive correlation between polyamines, its associated factors and GnRH-I along with significant negative correlation between polyamines, its associated factors and GnIH. This is the first study to report the effect of polyamines along with lactate or TNF-α or both on GnRH-I expression in GT1-7 cell line. TNF-α and lactate significantly decreased hypothalamic GnRH-I mRNA expression in GT1-7 cells when treated for 24 h. Polyamines (putrescine and agmatine) in contrast, significantly increased GnRH-I mRNA expression in GT1-7 cells when treated for 24 h. Also, polyamines increased GnRH-I mRNA expression when treated in presence of TNF-α or lactate thereby suggesting its neuro-protective role. This study also found 3809 differentially expressed genes through RNA-seq done between the hypothalamic GT1-7 cells treated with putrescine only versus TNF-α and putrescine. The present study suggests for the first time that putrescine treatment to TNFα-primed GT1-7 cells upregulates GnRH-I expression via regulation of several pathways such as calcium ion pathway, estrogen signaling, clock genes as well as regulating other metabolic process like neuronal differentiation and neurulation.


Assuntos
Poliaminas , Putrescina , Envelhecimento , Animais , Feminino , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Lactatos/metabolismo , Camundongos , Poliaminas/metabolismo , Putrescina/metabolismo , RNA Mensageiro/metabolismo , Roedores/genética , Roedores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Mol Cell Biochem ; 477(8): 2121-2132, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35545742

RESUMO

Diabetes type 1 (T1D) characterized by destruction of pancreatic ß-cells results in inadequate insulin production and hyperglycaemia. Generation of reactive oxygen species and glycosylation end-products stimulates toxic impacts on T1D. Dietary w-3 fatty acids present in Fish oil (FO) might be helpful in the prevention of oxidative stress and lipid peroxidation, thus, beneficial against T1D. But how the cellular secretion from ß-cells under influence of FO affects the glucose homeostasis of peri-pancreatic cells is poorly understood. In the current study, we aimed to introduce an in vitro model for T1D and evaluate its effectiveness in respect of alloxan treatment to pancreatic Min6 cells. We use alloxan in the Min6 pancreatic ß-cell line to induce cellular damage related to T1D. Further treatment with FO was seen to prevent cell death by alloxan and induce mRNA expression of both insulin 1 and insulin 2 isoforms under low-glucose conditions. From the first part of the study, it is clear that FO is effective to recover Min6 cells from the destructive effect of alloxan, and it worked best when given along with alloxan or given after alloxan treatment regime. FO-induced secretion of molecules from Min6 was clearly shown to regulate mRNA expression of key enzymes of carbohydrate metabolism in peri-pancreatic cell types. This is a pilot study showing that an improved in vitro approach of using Min6 along with muscle cells (C2C12) and adipose tissue cells (3T3-L1) together to understand the crosstalk of molecules could be used to check the efficacy of an anti-diabetic drug.


Assuntos
Diabetes Mellitus Tipo 1 , Óleos de Peixe , Aloxano , Diabetes Mellitus Tipo 1/tratamento farmacológico , Óleos de Peixe/farmacologia , Glucose/metabolismo , Humanos , Insulina/metabolismo , Projetos Piloto , RNA Mensageiro
11.
Chin J Traumatol ; 24(3): 180-182, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33648812

RESUMO

Early diagnosis of cerebral fat embolism in a patient with contradiction to MRI is challenging. Here we report an interesting case, where the raised optic nerve sheath diameter helped us to predict the early cerebral involvement with fat emboli in a left femoral shaft fracture patient. MRI scan could not be performed due to the presence of a metallic implant in the patient from a previous surgery. He was later diagnosed as an atypical presentation of fat embolism syndrome. Optic nerve sheath monitoring also helped us to guide further management of the patient.


Assuntos
Embolia Gordurosa , Fraturas do Fêmur , Embolia Intracraniana , Embolia Gordurosa/diagnóstico por imagem , Embolia Gordurosa/etiologia , Fraturas do Fêmur/complicações , Fraturas do Fêmur/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Nervo Óptico/diagnóstico por imagem
12.
Environ Monit Assess ; 193(11): 744, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34677689

RESUMO

Industrialization, urbanization, and rapid socioeconomic growth are the prime factors regarding development of an urban city. These activities deteriorate the environment slowly by increasing harmful pollutants and the impact of which will be observed in near future in terms of several natural calamities, disease, and ecological consequences. Various urban ecosystems like urban forestry, wetland, grassland, parks/gardens etc. are the main criteria of urban health in respect to delivering multiple of benefits to the surrounding biota. But these regulatory systems have been affected severely through different industrial pollution stresses resulting into deterioration of their physicochemical quality and biotic diversity. The study revealed that the annual average air pollution index (API) exceeded the higher threshold value (i.e. >100) during the study period and recognized Durgapur as the severely polluted region in West Bengal, India. The characteristics of major air pollutants like SO2, NOx, and suspended particulate matter (SPM) and their temporal trends have been evaluated. The objective of this study was to detect the effect of industrial pollution on the aforesaid urban ecosystems in terms of variable ecological services such as purification of polluted air, atmospheric regulation, reduction of noise, proper drainage of rainwater, and sewage treatment. The outcome of this review work was to evaluate thoroughly the physiological, biochemical, and morphological symptoms of plant species under air pollution stress. On the other hand, the effect of air pollution on human and animal populations regarding various diseases (like bronchitis, cardiopulmonary arrest, cancer, liver and kidney dysfunction) has also been discussed.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Animais , Ecossistema , Monitoramento Ambiental , Humanos , Índia , Material Particulado/análise , Saúde da População Urbana
13.
J Anaesthesiol Clin Pharmacol ; 37(3): 436-442, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759558

RESUMO

BACKGROUND AND AIMS: The purpose of this study was to prospectively examine the effects of pneumoperitoneum and the reverse Trendelenburg position on cardiac hemodynamics during laparoscopic cholecystectomy using transthoracic echocardiography (TTE). MATERIAL AND METHODS: In this prospective observational study, after institutional review board clearance, forty patients of either sex of ASA I-II status undergoing laparoscopic cholecystectomy were enrolled in the study. Changes in cardiac output, stroke volume, and ejection fraction were recorded using TTE at different time intervals: Preoperatively, before creation of pneumoperitoneum, 5 min after creation of pneumoperitoneum, and 5 min after setting the operative reverse Trendelenburg position with legs at the level of the hips. All statistical analyses were performed using the statistical program SPSS version 16 and P value less than 0.05 was considered as statistically significant. Data were examined using mixed analysis of variance (ANOVA) followed by post hoc Bonferroni correction. RESULTS: There was significant fall in cardiac output (CO) (45%, P < 0.001), stroke volume (SV) (42%, P < 0.001), and ejection fraction (EF) (31.8% change, P < 0.001) after creation of pneumoperitoneum with significant rise in MAP (11%, P < 0.001). But with reverse Trendelenburg position, there was a significant improvement of CO (30%), SV (28%), and EF (21% change) in comparison to values after pneumoperitoneum, but still remained below baseline. There was no change in heart rate at different time intervals. There was no significant difference in hemodynamics between ASA I and II patients. CONCLUSION: Patients undergoing laparoscopic cholecystectomy undergo significant hemodynamic changes after pneumoperitoneum and reverse Trendelenburg position.

14.
Mol Reprod Dev ; 86(12): 1963-1980, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31579974

RESUMO

The aim of this study was to evaluate the effect of putrescine on ovarian activity and the rate of embryonic development in Cynopterus sphinx during delayed development. The result showed the presence of a rate-limiting enzyme, ornithine decarboxylase-1, in both ovary and utero-embryonic unit of C. sphinx suggests a synthesis of putrescine in these sites. The corpus luteum showed increased, whereas utero-embryonic unit showed decreased production of putrescine during delayed development as compared with the normal development. The bat treated in vivo with putrescine during delayed development showed increase in progesterone and estradiol synthesis, correlated with increased expression of luteinizing hormone receptor, steroidogenic acute receptor protein, and 3ß-hydroxysteroid dehydrogenase through extracellular signal-regulated kinase (ERK1/2)-mediated pathway in the ovary; but showed increase in the weight and expression of progesterone receptor (PR), B-cell lymphoma 2, proliferating cell nucleus antigen, and vascular endothelial growth factor proteins in utero-embryonic unit. The in vitro treatment of putrescine showed stimulatory whereas treatment with an inhibitor of putrescine, 2-difluoromethylornithine caused an inhibitory effect on ovarian progesterone synthesis and cell proliferation, and cell survival in the utero-embryonic unit. In conclusion, the putrescine showed two separate roles during embryonic diapause, high concentration of putrescine in the ovary may support corpus luteum and basal synthesis of progesterone, whereas a low level of putrescine causes retarded embryonic development by inhibiting cell proliferation in the utero-embryonic unit. The bat treated with putrescine either directly promotes cell proliferation, cell survival, and angiogenic activities or acts indirectly increasing PR on utero-embryonic unit thereby activating development in delayed embryo in C. sphinx.


Assuntos
Quirópteros/embriologia , Diapausa/efeitos dos fármacos , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Ovário/metabolismo , Putrescina/farmacologia , Animais , Feminino
15.
J Theor Biol ; 461: 59-67, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30352238

RESUMO

Control of pest attack is an important aspect in agriculture to obtain healthy crop as well as high yield. Farming awareness is also equally important in pest management. Awareness campaign are made for making people aware of damages due to the pest and protect the crop from pests which ultimately leads to high crop yield. In this article, a mathematical model is proposed to study the effect of awareness among the people in crop pest management using plant biomass, pest and aware population. Pest population is divided into two compartments: susceptible pest and infected pest. We assume that the growth of awareness level is assumed to be proportional to the density of healthy pest in the crop field. Global source such as radio, TV etc. can increase the level of awareness. It is further assumed that aware people will adopt biological control methods like integrated pest management. Susceptible pests are made infected by this process as infected pest are less harmful to crop. Moreover, there may be some time delay in measuring the healthy pests in the crop field i.e. some delay may take place in taking necessary steps while controlling the pest attack. Thus we developed the model incorporating time delay into the system. The existence and the stability criteria of the equilibria are obtained in terms of the basic reproduction number. The Hopf-bifurcation analysis has been done at the endemic equilibrium considering time delay as the bifurcation parameter. Numerical simulations are carried out to justify the analytical results.


Assuntos
Agricultura/educação , Conscientização , Modelos Teóricos , Controle Biológico de Vetores/métodos , Número Básico de Reprodução , Simulação por Computador , Fatores de Tempo
16.
Toxicol Mech Methods ; 29(2): 110-118, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30273107

RESUMO

Altered lymphocytic activity and its subset ratio found responsible for initiating abnormal autoimmune responses in men and animals after excess iodine exposure. Study objective is to reveal excess iodine-induced impairment of peripheral blood lymphocytes (PBL), its functional status, antioxidant balance, DNA damage, proliferation assay, and serum cytokine levels (IL6 and TNF α)in adult male rats to understand the onset of autoimmune alterations if any indirectly that is unexplored. Experimental animals were grouped depending on doses of iodine(KI) treatment with moderately excess-7 mg/kg bw (100EI) and excessively excess-35 mg/kg bw (500EI)for 30 days to analyze IL6 and TNF α, hematological indices, oxidative stress, lymphocytic DNA damage, and proliferation status. Significant impairment in superoxide dismutase, catalase, GPx activities including elevated NO, LPO in lymphocytes of treated group, with increased IL6 and TNF α level, lymphocyte proliferation and DNA damage depending on doses of iodine. Therefore, excess iodine consumption leads to lymphocytic impairment that may be the potential cause of autoimmune thyroid diseases in long run. Highlights Excess iodine triggers the oxidative stress in lymphocytes. Excess iodine promotes the activity of pro-inflammatory cytokines. Excess iodine causes impairment of functional status of lymphocytes leading to immune-cytotoxicity. Excess iodine exacerbates the autoimmunity.


Assuntos
Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Iodeto de Potássio/toxicidade , Animais , Antioxidantes/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Dano ao DNA , Relação Dose-Resposta a Droga , Interleucina-6/sangue , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Masculino , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Medição de Risco , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue
17.
Chin J Traumatol ; 22(3): 172-176, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31047796

RESUMO

PURPOSE: Fat embolism syndrome (FES) is systemic manifestation of fat emboli in the circulation seen mostly after long bone fractures. FES is considered a lethal complication of trauma. There are various case reports and series describing FES. Here we describe the clinical characteristics, management in ICU and outcome of these patients in level I trauma center in a span of 6 months. METHODS: In this prospective study, analysis of all the patients with FES admitted in our polytrauma intensive care unit (ICU) of level I trauma center over a period of 6 months (from August 2017 to January 2018) was done. Demographic data, clinical features, management in ICU and outcome were analyzed. RESULTS: We admitted 10 cases of FES. The mean age of patients was 31.2 years. The mean duration from time of injury to onset of symptoms was 56 h. All patients presented with hypoxemia and petechiae but central nervous system symptoms were present in 70% of patients. The mean duration of mechanical ventilation was 11.7 days and the mean length of ICU stay was 14.7 days. There was excellent recovery among patients with no neurological deficit. CONCLUSION: FES is considered a lethal complication of trauma but timely management can result in favorable outcome. FES can occur even after fixation of the fracture. Hypoxia is the most common and earliest feature of FES followed by CNS manifestations. Any patient presenting with such symptoms should raise the suspicion of FES and mandate early ICU referral.


Assuntos
Embolia Gordurosa/etiologia , Embolia Gordurosa/prevenção & controle , Fraturas Ósseas/complicações , Adolescente , Adulto , Doenças do Sistema Nervoso Central/etiologia , Diagnóstico Precoce , Embolia Gordurosa/diagnóstico , Humanos , Hipóxia/etiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Masculino , Avaliação de Resultados da Assistência ao Paciente , Fatores de Tempo , Centros de Traumatologia/estatística & dados numéricos , Adulto Jovem
18.
Small ; 14(32): e1801510, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29998514

RESUMO

The formation of all-organic dual spin valves (DSVs) with three organic spin-selective layers, that is, spin-injection, spin-detection, and an additional spin-filtering layer at the intermediate, is reported. As spin-selective layers, manganese- and cobalt phthalocyanines, which are well-known single-molecule magnets, are used in their immobilized forms, so that all-organic DSVs can be prefabricated for characterization. The three spin-selective layers have provided four configurations with at most two spin-flip interfaces enforcing spin-flipping at the two nonmagnetic organic spacer layers, for which copper phthalocyanine is used. Since a couple of the four configurations have exhibited similar resistivities, the degeneracy in the resistive-states is broken through asymmetric spin-injection and spin-detection layers and also through asymmetric thickness of the nonmagnetic spacer layers. When both the spin-flip interfaces are made operative independently, a 2-bit logic with four distinct resistive states can be achieved.

19.
J Biol Inorg Chem ; 23(8): 1331-1349, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30302601

RESUMO

We report the biological activity of three Cu(II) complexes [Cu(pabt)Cl] (1), [Cu(pma)Cl] (2), and [Cu(pdta)Cl]Cl (3) (pabt = N-(2-mercaptophenyl)-2'-pyridylmethylenimine, pma = N-(2-pyridylmethyl)-2-mercaptoaniline, pdta = 2,2'-di(pyridyl-2-methyleneimine)diphenyl disulfide). 1-3 display four-line EPR multiplet in solution at RT suggesting that these are mononuclear. DNA-binding studies using spectrophotometric titration of these complexes with calf thymus DNA showed binding through intercalation mode which was found to be consistent with the observation of increased viscosity of DNA and quenching of fluorescence of ethidium bromide bound DNA in the presence of these complexes. All three complexes were found to be efficient in bringing about oxidative and hydrolytic cleavage of DNA. The proposed mechanism of hydrolytic DNA cleavage has been discussed. MTT assay showed remarkable cytotoxicity on cervical cancer HeLa cell line and the IC50 values were 1.27, 4.13, and 3.92 µM for 1, 2 and 3, respectively, as compared to the IC50 value (13 µM) reported for cisplatin in HeLa cells. AO/PI and Annexin-V/PI assay suggest the induction of cell death primarily via apoptotic pathway. Nuclear staining using DAPI was used to assess changes in nuclear morphology during apoptotic cell death. The role of reactive oxygen species (ROS) for induction of apoptotic cell death was studied using H2DCF-DA assay and the result suggests that the generation of ROS by the complexes may be a possible cause for their antiproliferative activity. TUNEL assay showed DNA fragmentation in apoptotic cells. Cell cycle analysis using flow cytometry showed significant increase in the G2/M phase in HeLa cells by the compounds 1-3. Mononuclear Cu(II) complexes display remarkable cytotoxicity against cervical cancer HeLa cell line. The generation of ROS by the complexes may be a cause of their antiproliferative activity. Fluorescent images from DAPI staining assay revealed that the cells undergoing apoptosis displayed typical features like cell shrinkage, membrane blebbing, chromatin condensation and nuclear fragmentation. TUNEL assay showed DNA fragmentation in apoptotic cells.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Cobre/química , DNA/química , Bases de Schiff/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/toxicidade , Bovinos , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Clivagem do DNA/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Hidrólise , Substâncias Intercalantes/síntese química , Substâncias Intercalantes/química , Substâncias Intercalantes/farmacologia , Substâncias Intercalantes/toxicidade , Ligantes , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Bases de Schiff/síntese química , Bases de Schiff/química , Bases de Schiff/toxicidade , Viscosidade
20.
Phys Rev Lett ; 120(11): 117204, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29601734

RESUMO

The honeycomb Kitaev-Heisenberg model is a source of a quantum spin liquid with Majorana fermions and gauge flux excitations as fractional quasiparticles. Here we unveil the highly unusual low-temperature heat conductivity κ of α-RuCl_{3}, a prime candidate for realizing such physics: beyond a magnetic field of B_{c}≈7.5 T, κ increases by about one order of magnitude, both for in-plane as well as out-of-plane transport. This clarifies the unusual magnetic field dependence unambiguously to be the result of severe scattering of phonons off putative Kitaev-Heisenberg excitations in combination with a drastic field-induced change of the magnetic excitation spectrum. In particular, an unexpected, large energy gap arises, which increases linearly with the magnetic field, reaching remarkable ℏω_{0}/k_{B}≈50 K at 18 T.

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