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Genetically encoded optical indicators and actuators of neural activity allow for all-optical investigations of signaling in the nervous system. But commonly used indicators, actuators, and expression strategies are poorly suited for systematic measurements of signal propagation at brain scale and cellular resolution. Large-scale measurements of the brain require indicators and actuators with compatible excitation spectra to avoid optical crosstalk. They must be highly expressed in every neuron but at the same time avoid lethality and permit the animal to reach adulthood. Their expression must also be compatible with additional fluorescent labels to locate and identify neurons, such as those in the NeuroPAL cell identification system. We present TWISP, a transgenic worm for interrogating signal propagation, that addresses these needs and enables optical measurements of evoked calcium activity at brain scale and cellular resolution in the nervous system of the nematode Caenorhabditis elegans. In every neuron we express a nonconventional optical actuator, the gustatory receptor homolog GUR-3 + PRDX-2, under the control of a drug-inducible system QF + hGR, and a calcium indicator GCAMP6s, in a background with additional fluorophores from the NeuroPAL cell ID system. We show that this combination, but not others tested, avoids optical crosstalk, creates strong expression in the adult, and generates stable transgenic lines for systematic measurements of signal propagation in the worm brain.
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Animales Modificados Genéticamente , Caenorhabditis elegans , Neuronas , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Neuronas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Calcio/metabolismo , Transducción de Señal , Señalización del Calcio , Encéfalo/metabolismoRESUMEN
BACKGROUND: Myocardial infarction (MI), also referred to as a "heart attack," is brought on by a partial or total interruption of blood supply to the myocardium. Myocardial infarction can be "silent," go undiagnosed, or it can be a catastrophic occurrence that results in hemodynamic decline and untimely death. In recent years, herbal remedies for MI have become effective, secure, and readily accessible. OBJECTIVE: The purpose of this review was to examine the medicinal plants and phytochemicals that have been used to treat MI in order to assess the potential contribution of natural substances to the development of herbal MI treatments. METHODOLOGY: A literature search was employed to find information utilizing electronic databases, such as Web of Science, Google Scholar, PubMed, Sci Finder, Reaxys, and Cochrane. RESULTS: The identification of 140 plants from 12 families led to the abstraction of data on the plant families, parts of the plant employed, chemical contents, extracts, model used, and dose. CONCLUSION: The majority of the MI plants, according to the data, belonged to the Fabaceae (11%) and Asteraceae (9%) families, and the most prevalent natural components in plants with MI were flavonoids (43%), glucosides (25%), alkaloids (23%), phenolic acid (19%), saponins (15%), and tannins (12%).
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Infarto del Miocardio , Fitoterapia , Extractos Vegetales , Plantas Medicinales , Infarto del Miocardio/tratamiento farmacológico , Humanos , Plantas Medicinales/química , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Fitoquímicos/uso terapéutico , Fitoquímicos/análisisRESUMEN
Shape memory alloys (SMAs) have become the most common choice for the development of mini- and micro-type soft bio-inspired robots due to their high power-to-weight ratio, ability to be installed and operated in limited space, silent and vibration-free operation, biocompatibility, and corrosion resistance properties. Moreover, SMA spring-type actuators are used for developing different continuum robots, exhibiting high degrees of freedom and flexibility. Spring- or any elastic-material-based antagonistic or biasing force is mostly preferred among all other biasing techniques to generate periodic oscillation of SMA actuator-based robotic body parts. In this model-based study, SMA-based spring-type actuators were used to develop a carangiform-type robotic fishtail. Fin size optimization for the maximization of forward thrust was performed for the developed system by varying different parameters, such as caudal fin size, current through actuators, pulse-width modulation signal (PWM), and operating depth. A caudal fin with a mixed fin pattern between the Lunate and Fork "Lunafork" and a fin area of approximately 5000 mm2 was found to be the most effective for the developed system. The maximum forward thrust developed by this fin was recorded as 40 gmf at an operation depth of 12.5 cm in a body of still water.
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Aß1-40 peptide and Aß1-42 peptide are the building units of beta-amyloid plaques present in Alzheimer's disease (AD)-affected brain. The binding affinity of various divalent metal ions such as Cu and Zn present in AD-affected brain with different amino acids available in Aß-peptide became the focus to explore their role in soluble neurotoxic oligomer formation. Cu2+ metal ions are known to enhance the neurotoxicity of the Aß1-42 peptide by catalyzing the formation of soluble neurotoxic oligomers. The competitive preference of both Cu2+ and Zn2+ simultaneously to interact with the Aß-peptide is unknown. The divalent Cu and Zn ions were inserted in explicit aqueous Aß1-42 peptide configurations to get insights into the binding competence of these metal ions with peptides using classical molecular dynamics (MD) simulations. The metal-ion interactions reveal that competitive binding preferences of various peptide sites become metal-ion-specific and differ significantly. For Cu2+, interactions are found to be more significant with respect to those of Asp-7, His-6, Glu-11, and His-14. Asp-1, Glu-3, Asp-7, His-6, Glu-11, and His-13 amino acid residues show higher affinity toward Zn2+ ions. MD simulations show notable variation in the solvent-accessible surface area in the hydrophobic region of the peptide. Infinitesimal mobility was obtained for Zn2+ compared to Cu2+ in an aqueous solution and Cu2+ diffusivity deviated significantly at different time scales, proving its labile features in aqueous Aß1-42 peptides.
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The chronic exposure of humans to the toxic metal cadmium (Cd), either occupational or from food and air, causes various diseases, including neurodegenerative conditions, dysfunction of vital organs, and cancer. While the toxicology of Cd and its effect on the homeostasis of biologically relevant elements is increasingly recognized, the spatial distribution of Cd and other elements in Cd toxicity-caused diseases is still poorly understood. Here, we use Caenorhabditis elegans as a non-mammalian multicellular model system to determine the distribution of Cd at the tissue and cellular resolution and its effect on the internal levels and the distribution of biologically relevant elements. Using inductively coupled plasma-mass spectrophotometry (ICP-MS), we show that exposure of worms to Cd not only led to its internal accumulation but also significantly altered the C. elegans ionome. Specifically, Cd treatment was associated with increased levels of toxic elements such as arsenic (As) and rubidium (Rb) and a decreased accumulation of essential elements such as zinc (Zn), copper (Cu), manganese (Mn), calcium (Ca), cobalt (Co) and, depending on the Cd-concentration used in the assay, iron (Fe). We regarded these changes as an ionomic signature of Cd toxicity in C. elegans. We also show that supplementing nematode growth medium with Zn but not Cu, rescues Cd toxicity and that mutant worms lacking Zn transporters CDF-1 or SUR-7, or both are more sensitive to Cd toxicity. Finally, using synchrotron X-Ray fluorescence Microscopy (XRF), we showed that Cd significantly alters the spatial distribution of mineral elements. The effect of Cd on the distribution of Fe was particularly striking: while Fe was evenly distributed in intestinal cells of worms grown without Cd, in the presence of Cd, Fe, and Cd co-localized in punctum-like structures in the intestinal cells. Together, this study advances our understanding of the effect of Cd on the accumulation and distribution of biologically relevant elements. Considering that C. elegans possesses the principal tissues and cell types as humans, our data may have important implications for future therapeutic developments aiming to alleviate Cd-related pathologies in humans.
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Genetically encoded optical indicators and actuators of neural activity allow for all-optical investigations of signaling in the nervous system. But commonly used indicators, actuators and expression strategies are poorly suited for systematic measurements of signal propagation at brain scale and cellular resolution. Large scale measurements of the brain require indicators and actuators with compatible excitation spectra to avoid optical crosstalk. They must be highly expressed in every neuron but at the same time avoid lethality and permit the animal to reach adulthood. And finally, their expression must be compatible with additional fluorescent labels to locate and identify neurons, such as those in the NeuroPAL cell identification system. We present TWISP, a Transgenic Worm for Interrogating Signal Propagation, that address these needs and enables optical measurements of evoked calcium activity at brain scale and cellular resolution in the nervous system of the nematode Caenorhabditis elegans. We express in every neuron a non-conventional optical actuator, the gustatory receptor homolog GUR-3+PRDX-2 under the control of a drug-inducible system QF+hGR, and calcium indicator GCAMP6s, in a background with additional fluorophores of the NeuroPAL cell ID system. We show that this combination, but not others tested, avoids optical-crosstalk, creates strong expression in the adult, and generates stable transgenic lines for systematic measurements of signal propagation in the worm brain.
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OBJECTIVES: Elaeocarpus ganitrus, a member of the Eleocarpaceae family, is valued in Hinduism and Ayurveda, and is frequently used as a remedy for a variety of illnesses. The plant is reputed to treat a number of stomach issues. The purpose of the study was to produce high-quality scientific data regarding gastroprotective behavior, docking experiments with cholinergic receptors, and HPTLC (with lupeol and ursolic acid). To develop the mechanism of herbal extracts, in vitro anticholinergic and antihistaminic activities were evaluated. Different leaf extracts were treated with various reagents to determine the presence of various metabolites. An examination of the histopathology was conducted to determine the full impact of the extract. METHODS: Methanolic extract was chosen for HPTLC investigations after extraction with various solvents. A mobile phase of toluene, ethylacetate, and formic acid (8:2:0.1) was chosen. Molecular docking was utilized to examine how ursolic acid and lupeol are bound to cholinergic receptors (M3). Different extracts (aqueous and ethanolic) were tested for their ability to provide gastroprotection in Wistar rats at different doses (200 and 400 mg/kg). RESULTS: Phytochemical analysis of different extracts showed the presence of different primary and secondary metabolites. HPTLC data showed the presence of both standards. Docking studies exhibited very good interactions with the M3 receptor. Pharmacological studies revealed that extract-treated groups significantly reduced the ulcer index in all of the models mentioned above. The histopathological analysis clearly supports the biochemical studies, which were conducted utilizing various doses and found to be effective in a dose-dependent manner. The in vitro analysis proved that the abovementioned extracts may act as antagonists of acetylcholine and histamine. CONCLUSION: The data obtained would be valuable for the production of the monograph of the plant and conducting concept-related clinical studies in the future. More investigation is required since the gathered scientific data may lead to new research opportunities.
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Antiulcerosos , Elaeocarpaceae , Úlcera Gástrica , Ratas , Animales , Ratas Wistar , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Extractos Vegetales/química , Simulación del Acoplamiento Molecular , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/patología , Antiulcerosos/farmacología , Antiulcerosos/uso terapéutico , Antiulcerosos/química , Ácido UrsólicoRESUMEN
Background: We have been in constant search of novel innovations to decrease the high morbidity after Pancreaticoduodenectomy (PD). Pancreaticojejunostomy (PJ) and pancreaticogastrostomy (PG) are the two different methods of reconstruction after PD. However, the existing data is ambiguous in supporting either of them as the preferred technique of reconstruction. Methods: This was a single-center prospective observational study that included 64 patients who underwent PD over two years. We compared PG with PJ as a method of reconstruction after PD. The primary objective was to assess whether PG decreases the rate of postoperative pancreatic fistula (POPF) rates or not. Secondary objectives comprised analysis of perioperative outcomes, 30-day and 90-day mortality. Results: Pancreatic fistula was significantly lower in PG as compared to the PJ group (24% vs. 47%) with a p-value of 0.027. The incidence of clinically pertinent (grade B) fistula was only 3% in the PG group and 32% in the PJ group. PG group had a higher incidence of post pancreatectomy hemorrhage (PPH) and delayed gastric emptying (DGE). No statistically significant difference was seen between either group need for blood transfusion, re-exploration, re-admissions, ICU stay, or length of hospital stay, and 30-day and 90-day mortality. Pancreatic texture and high BMI were independent predictors for pancreatic fistula. Conclusion: PG when compared to PJ for reconstruction after PD, decreases the rate of POPF significantly; however, it is associated with an elevated risk of DGE and PPH. There was no difference in 30-day and 90-day mortality between both the treatment groups.
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Neurodegenerative diseases such as Alzheimer's disease (AD) are associated with progressive neuronal cell death, and they are commonly correlated with aberrant protein misfolding and aggregation of Aß peptides. Transition metal ions (Cu, Fe, and Zn) have been shown to promote aggregation and oxidative stress through formation of Aß-metal complexes. In this context, integrating molecular scaffolds rationally is used here to generate multifunctional molecules as modulators for metal-induced abnormalities. This work encompasses two azo-stilbene (AS)-derived compounds (AS-HL1 and AS-HL2), the rationale behind the design, their synthesis, characterization, and metal chelation ability [Cu(II) and Zn(II)]. The molecular frameworks of the designed compounds consist of stilbene as an Aß-interacting moiety, whereas N,N,O and N,N,N,O donor atoms are linked to generate the metal chelation moiety. Furthermore, we went on exploring their multifunctionality with respect to (w.r.t.) (i) their metal chelating capacities and (ii) their utility to modulate the aggregation pathways of both metal-free and metal-bound amyloid-ß, (iii) scavenge free radicals, and (iv) inhibit the activity of acetylcholinesterase and (v) cytotoxicity. Moreover, the compounds were able to sequester Cu2+ from the Aß-Cu complex as studied by the UV-visible spectroscopic assay. Molecular docking studies were also performed with Aß and acetylcholinesterase enzyme. Overall, the studies presented here qualify these molecules as promising candidates for further investigation in the quest for finding a treatment for Alzheimer's disease.
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Enfermedad de Alzheimer , Estilbenos , Acetilcolinesterasa , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Aminas , Péptidos beta-Amiloides/química , Quelantes/química , Cobre/química , Humanos , Metales , Simulación del Acoplamiento Molecular , Piridinas , Estilbenos/farmacologíaRESUMEN
The enormous use of cutting fluid in machining leads to an increase in machining costs, along with different health hazards. Cutting fluid can be used efficiently using the MQL (minimum quantity lubrication) method, which aids in improving the machining performance. This paper contains multiple responses, namely, force, surface roughness, and temperature, so there arises a need for a multicriteria optimization technique. Therefore, in this paper, multiobjective optimization based on ratio analysis (MOORA), VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR), and technique for order of preference by similarity to ideal solution (TOPSIS) are used to solve different multiobjective problems, and response surface methodology is also used for optimization and to validate the results obtained by multicriterion decision-making technique (MCDM) techniques. The design of the experiment is based on the Box-Behnken technique, which used four input parameters: feed rate, depth of cut, cutting speed, and nanofluid concentration, respectively. The experiments were performed on AISI 304 steel in turning with minimum quantity lubrication (MQL) and found that the use of hybrid nanofluid (Alumina-Graphene) reduces response parameters by approximately 13% in forces, 31% in surface roughness, and 14% in temperature, as compared to Alumina nanofluid. The response parameters are analyzed using analysis of variance (ANOVA), where the depth of cut and feed rate showed a major impact on response parameters. After using all three MCDM techniques, it was found that, at fixed weight factor with each MCDM technique, a similar process parameter was achieved (velocity of 90 m/min, feed of 0.08 mm/min, depth of cut of 0.6 mm, and nanoparticle concentration of 1.5%, respectively) for optimum response. The above stated multicriterion techniques employed in this work aid decision makers in selecting optimum parameters depending upon the desired targets. Thus, this work is a novel approach to studying the effectiveness of hybrid nanofluids in the machining of AISI 304 steel using MCDM techniques.
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Introduction Infection of cardiac implantable electrical devices (CIEDs) may lead to serious complications. Complete CIED explantation is expensive, requires expertise, not free from complications, and may not be an option in patients with device dependence. Aim To highlight that carefully selected infected CIEDs can be salvaged by placing the device in a subpectoral pocket below the pectoralis major muscle. We conducted a retrospective descriptive observational study. Material and Methods Twelve patients (10 male and two female) with erosion, exposure or infection of infraclavicular, subcutaneously placed CIED were treated over a 30-month period between July 2018 and December 2020. The technique involved debridement and excision of a peridevice capsule, creating a subpectoral pocket beneath the pectoralis major muscle, and placing the CIED in a new pocket with total muscle coverage and closure of skin without tension. Results Twelve patients ( m = 10; f = 2) with a mean age of 65 years (range, 46-82 years) presented with infection of CIED within 9 months of implantation. None had sepsis or endocarditis. In nine patients, CIEDs were successfully salvaged with relocation to subpectoral pocket. Mean follow-up was 20 months (range, 8-30 months). Three out of 12 developed reinfection that ultimately required CIED explantation. There was no mortality. Conclusion In the absence of sepsis or endocarditis, infected CIEDs may be attempted at salvage by subpectoral pocket placement. This obviates the need for potentially risky explantation or replacement of expensive CIEDs.
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Actinomycotic mycetoma is a disease of the tropical region and usually presents as a chronic, suppurative and deforming granulomatous infection. We present an unusual case of actinomycotic mycetoma of the abdominal wall that was found to infiltrate into the bowel. A 51 year-old man presented with pain and swelling in the left flank of 2-year duration. Even after comprehensive preoperative evaluation with advanced radiological imaging, biochemistry and pathology, the diagnosis could not be arrived at. Histopathological examination of the excised specimen after the surgery guided to the diagnosis of actinomycotic mycetoma, which entirely changed the management in the postoperative period. We propose that mycetoma should be kept as a possible differential diagnosis for anterior abdominal wall swelling in the indicated clinical setting and the investigations be done keeping the same in mind. Otherwise, a lot of valuable time may be lost allowing the disease to progress further.
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Pared Abdominal/diagnóstico por imagen , Actinomicosis/diagnóstico , Colon Descendente/diagnóstico por imagen , Enfermedades del Colon/diagnóstico , Micetoma/diagnóstico , Pared Abdominal/patología , Pared Abdominal/cirugía , Actinomicosis/patología , Actinomicosis/terapia , Antibacterianos/uso terapéutico , Biopsia con Aguja Fina , Colon Descendente/patología , Colon Descendente/cirugía , Enfermedades del Colon/patología , Enfermedades del Colon/terapia , Cisticercosis/diagnóstico , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Micetoma/patología , Micetoma/terapia , Sarcoma/diagnóstico , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
This article represents a three-dimensional dynamical system which studies the impact of additional food on the plankton system in the absence and presence of toxicity. It is determined that available additional food and toxin produced by phytoplankton play a crucial role in the termination of harmful algal blooms. The significance of the parameter, additional food, lies in the fact that its limited availability can terminate planktonic blooms when the concentration of toxicity is high. The positivity, boundedness, and permanence of the system are proved to make the model biologically valid. The existence of different biological feasible equilibria and their local stability criteria are determined analytically under certain conditions. The Hopf-bifurcation analysis is carried out by considering additional food as a bifurcation parameter. All the theoretical results are verified numerically. Our results indicate that the prey and predator population are never extinct and survive at a stable level when the additional food is available for the predator population.
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Cadena Alimentaria , Modelos Teóricos , Fitoplancton/fisiología , Dinámica Poblacional , Conducta Predatoria/fisiología , Animales , Plancton/fisiologíaRESUMEN
The coordination chemistry of transition metal ions (Fe, Cu, Zn) with the amyloid-ß (Aß) peptides has attracted a lot of attention in recent years due to its repercussions in Alzheimer's disease (AD). Aß peptide undergoes self-aggregation to form amyloid plaques and soluble oligomers, which are believed to play a central role in AD pathology. Metal ions and Aß-metal adducts can generate toxic radical species capable of modifying biomolecules, ultimately causing death of the neuronal cells. The impact of these metal ions on Aß aggregation and neurotoxic species formation is still not well understood. A large number of reports indicate that transition metal ions such as Cu and Zn have significant effects on Aß peptide aggregation and stabilization of neurotoxic soluble Aß aggregates; some of these reports are contradictory too. A review on the effects of Cu and Zn metal ions on Aß peptide aggregation due to their coordination with these peptides is presented herein. The review includes brief discussions with regards to the levels of Cu and Zn in an AD affected brain, structures of Aß peptides, and the coordination of Aß peptides with Cu and Zn. In the current scenario, a consensus appears to be emerging regarding the coordination mode and the effect of metal ions (especially Cu and Zn) on the aggregation of Aß peptides. Towards the end, a short discussion on current research trends in the field of bifunctional metal chelators for tackling the metal effect on Aß aggregation and toxicity has also been presented. It is expected that this review would aid in gaining a better understanding of the current status of various aspects of AD from an inorganic chemistry perspective.
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Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Cobre/metabolismo , Agregación Patológica de Proteínas/metabolismo , Zinc/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Cobre/química , Descubrimiento de Drogas , Humanos , Modelos Moleculares , Agregación Patológica de Proteínas/tratamiento farmacológico , Agregación Patológica de Proteínas/patología , Zinc/químicaRESUMEN
Aerobic reaction of the ligand H2L1, 2-(2-phenylazo)-anilino-4,6-di-tert-butylphenol, CoCl2·6H2O and Et3N in MeOH under refluxing conditions produces, after work-up and recrystallization, black crystals of [Co(L1)2] (1). When examined by cyclic voltammetry, 1 displays in CH2Cl2 three one-electron redox responses: two oxidative, E11/2 = 0.30 V (peak-to-peak separation, ΔEp = 100 mV) and E21/2 = 1.04 V (ΔEp = 120 mV), and one reductive E1/2 = -0.27 V (ΔEp = 120 mV) vs. SCE. Consequently, 1 is chemically oxidized by 1 equiv. of [FeIII(η5-C5H5)2][PF6], affording the isolation of deep purple crystals of [Co(L1)2][PF6]·2CH2Cl2 (2), and one-electron reduction with [CoII(η5-C5H5)2] yielded bluish-black crystals of [CoIII(η5-C5H5)2][Co(L1)2]·MeCN (3). A solid sample of 1 exhibits temperature-independent (50-300 K) magnetism, revealing the presence of a free radical (S = 1/2), which exhibits an isotropic EPR signal (g = 2.003) at 298 K and at 77 K an eight-line feature characteristic of hyperfine-interaction of the radical with the Co (I = 7/2) nucleus. Based on X-ray structural parameters of 1-3 at 100 K, magnetic and EPR spectral behaviour of 1, and variable-temperature (233-313 K) 1H NMR spectral features of 1-3 and 13C NMR spectra at 298 K of 2 and 3 in CDCl3 point to the electronic structure of the complexes as either [CoIII{(LAP)2-}{(LISQ)}Ë-] or [CoIII{(L1)2}Ë3-] (delocalized nature favours the latter description) (1), [CoIII{(LISQ)Ë-}2][PF6]·2CH2Cl2 (2) and [CoIII(η5-C5H5)2][CoIII{(LAP)2-}2]·MeCN (3) [(LAP)2- and (LISQ)Ë- represent the redox-level of coordinated ligands o-amidophenolate(2-) ion and o-iminobenzosemiquinonate(1-) π-radical ion, respectively]. Notably, all the observed redox processes are ligand-centred. To the best of our knowledge, this is the first time that six-coordinate complexes of a common tridentate o-aminophenolate-based ligand have been structurally characterized for the parent 1, its monocation 2 and the monoanion 3 counterparts. Temperature-dependent 1H NMR spectra reveal the existence of valence-tautomeric equilibria in 1-3. Density Functional Theory (DFT) calculations at the B3LYP-level of theory corroborate the electronic structural assignment of 1-3 from experimental data. The origins of the observed UV-VIS-NIR absorptions for 1-3 have been assigned, based on time-dependent (TD)-DFT calculations.
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Copper plays key roles in catalytic and regulatory biochemical reactions essential for normal growth, development, and health. Dietary copper deficiencies or mutations in copper homeostasis genes can lead to abnormal musculoskeletal development, cognitive disorders, and poor growth. In yeast and mammals, copper is acquired through the activities of the CTR1 family of high-affinity copper transporters. However, the mechanisms of systemic responses to dietary or tissue-specific copper deficiency remain unclear. Here, taking advantage of the animal model Caenorhabditis elegans for studying whole-body copper homeostasis, we investigated the role of a C. elegans CTR1 homolog, CHCA-1, in copper acquisition and in worm growth, development, and behavior. Using sequence homology searches, we identified 10 potential orthologs to mammalian CTR1 Among these genes, we found that chca-1, which is transcriptionally up-regulated in the intestine and hypodermis of C. elegans during copper deficiency, is required for normal growth, reproduction, and maintenance of systemic copper balance under copper deprivation. The intestinal copper transporter CUA-1 normally traffics to endosomes to sequester excess copper, and we found here that loss of chca-1 caused CUA-1 to mislocalize to the basolateral membrane under copper overload conditions. Moreover, animals lacking chca-1 exhibited significantly reduced copper avoidance behavior in response to toxic copper conditions compared with WT worms. These results establish that CHCA-1-mediated copper acquisition in C. elegans is crucial for normal growth, development, and copper-sensing behavior.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/metabolismo , Proteínas de Transporte de Catión/metabolismo , Membrana Celular/metabolismo , Cobre/metabolismo , Animales , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte de Catión/genética , Transportador de Cobre 1 , Homeostasis , Intestinos , Transporte Iónico , Reproducción , Activación TranscripcionalRESUMEN
Arsenic is globally infamous for inducing immunosuppression associated with prevalence of opportunistic infection in exposed population, although the mechanism remains elusive. In this study, we investigate the effect of arsenic exposure on thymocyte lineage commitment and the involvement of regulatory T cells (Treg) in arsenic-induced immunosuppression. Male Balb/c mice were exposed to 0.038, 0.38 and 3.8 ppm sodium arsenite for 7, 15 and 30 days through oral gavage. Arsenic exposure promoted CD4 lineage commitment in a dose dependent manner supported by the expression of ThPOK in thymus. Arsenic also increased splenic CD4+ T cells and promoted their differentiation into Treg cells. In parallel, arsenic exposure induced immunosuppression characterized by low cytokine secretion from splenocytes and increased susceptibility to Mycobacterium fortuitum (M. fortuitum) infection. Therefore, we linked arsenic-induced rise in Treg cells with suppressed Th1 and Th2 related cytokines, which has been reversed by inhibition of Treg cells in-vivo using wortmannin. Other parameters like body weight, kidney and liver function, histoanatomy of thymus and spleen as well as thymocyte and splenocytes viability were unaltered by arsenic exposure. Taken together our findings indicated that environmentally relevant dose of arsenic enhanced differentiation of Treg cells which in turn induce immunosuppression in experimental animals.
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Arsénico/farmacología , Antígenos CD4/metabolismo , Citocinas/biosíntesis , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/metabolismo , Timocitos/efectos de los fármacos , Timocitos/metabolismo , Animales , Biomarcadores , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linaje de la Célula , Subunidad alfa 3 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 3 del Factor de Unión al Sitio Principal/metabolismo , Recuento de Linfocitos , Masculino , Ratones , Bazo/citología , Bazo/inmunología , Bazo/metabolismo , Subgrupos de Linfocitos T/inmunología , Timocitos/inmunología , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Zinc oxide nanoparticle (ZnO-NP) is one of the most widely used engineered nanoparticles. Upon exposure, nanoparticle can eventually reach the brain through various routes, interact with different brain cells, and alter their activity. Microglia is the fastest glial cell to respond to any toxic insult. Nanoparticle exposure can activate microglia and induce neuroinflammation. Simultaneous to activation, microglial death can exacerbate the scenario. Therefore, we focused on studying the effect of ZnO-NP on microglia and finding out the pathway involved in the microglial death. The present study showed that the 24 h inhibitory concentration 50 (IC50) of ZnO-NP for microglia is 6.6 µg/ml. Early events following ZnO-NP exposure involved increase in intracellular calcium level as well as reactive oxygen species (ROS). Neither of NADPH oxidase inhibitors, apocynin, (APO) and diphenyleneiodonium chloride (DPIC) were able to reduce the ROS level and rescue microglia from ZnO-NP toxicity. In contrary, N-acetyl cysteine (NAC) showed opposite effect. Exogenous supplementation of superoxide dismutase (SOD) reduced ROS significantly even beyond control level but partially rescued microglial viability. Interestingly, pyruvate supplementation rescued microglia near to control level. Following 10 h of ZnO-NP exposure, intracellular ATP level was measured to be almost 50 % to the control. ZnO-NP-induced ROS as well as ATP depletion both disturbed mitochondrial membrane potential and subsequently triggered the apoptotic pathway. The level of apoptosis-inducing proteins was measured by western blot analysis and found to be upregulated. Taken together, we have deciphered that ZnO-NP induced microglial apoptosis by NADPH oxidase-independent ROS as well as ATP depletion.
Asunto(s)
Muerte Celular/efectos de los fármacos , Nanopartículas del Metal/administración & dosificación , Microglía/efectos de los fármacos , NADPH Oxidasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Óxido de Zinc/administración & dosificación , Acetofenonas/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Inhibidores Enzimáticos/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Microglía/metabolismo , NADPH Oxidasas/antagonistas & inhibidores , Compuestos Onio/farmacología , Estrés Oxidativo/efectos de los fármacos , Ácido Pirúvico/farmacologíaRESUMEN
Copper plays key catalytic and regulatory roles in biochemical processes essential for normal growth, development, and health. Defects in copper metabolism cause Menkes and Wilson's disease, myeloneuropathy, and cardiovascular disease and are associated with other pathophysiological states. Consequently, it is critical to understand the mechanisms by which organisms control the acquisition, distribution, and utilization of copper. The intestinal enterocyte is a key regulatory point for copper absorption into the body; however, the mechanisms by which intestinal cells transport copper to maintain organismal copper homeostasis are poorly understood. Here, we identify a mechanism by which organismal copper homeostasis is maintained by intestinal copper exporter trafficking that is coordinated with extraintestinal copper levels in Caenorhabditis elegans Specifically, we show that CUA-1, the C. elegans homolog of ATP7A/B, localizes to lysosome-like organelles (gut granules) in the intestine under copper overload conditions for copper detoxification, whereas copper deficiency results in a redistribution of CUA-1 to basolateral membranes for copper efflux to peripheral tissues. Worms defective in gut granule biogenesis exhibit defects in copper sequestration and increased susceptibility to toxic copper levels. Interestingly, however, a splice isoform CUA-1.2 that lacks a portion of the N-terminal domain is targeted constitutively to the basolateral membrane irrespective of dietary copper concentration. Our studies establish that CUA-1 is a key intestinal copper exporter and that its trafficking is regulated to maintain systemic copper homeostasis. C. elegans could therefore be exploited as a whole-animal model system to study regulation of intra- and intercellular copper trafficking pathways.
Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Transporte de Catión/metabolismo , Membrana Celular/metabolismo , Cobre/metabolismo , Homeostasis , Mucosa Intestinal/metabolismo , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Intestinos/crecimiento & desarrollo , Transporte de ProteínasRESUMEN
Port site metastasis (PSM) is a known sequela of laparoscopic cholecystectomy in carcinoma gallbladder. While they are associated with poor prognosis, isolated PSM may represent a subset with better outcomes. We conducted a clinical audit of 33 cases of PSMs treated over a 6-year period. This included 26 cases of isolated PSM and 7 cases of PSM with systemic metastases. The mean time interval between index surgery and appearance of PSM was longer in the patients with isolated PSM (33.11 vs 25.5 months, p = 0.041). Isolated PSMs were treated with surgery and chemotherapy while the others were treated with palliative chemotherapy only. Two out of 27 cases (7 %) of isolated PSM had disease progression during therapy while 3 out of the 6 cases (50 %) of PSM with other sites of recurrences had disease progression while on treatment. Time to disease progression was significant more in cases of isolated PSM (17.14 vs 7.66 months, p = 0.034). The mean survival time too was significantly more in these cases (25.33 vs 15.66 months, p = 0.015). Isolated PSMs in case of gallbladder cancer may represent a distinct disease entity. Aggressive surgical management in addition to systemic chemotherapy may result in a reasonable survival advantage.