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1.
Int J Surg Case Rep ; 122: 110015, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39032349

RESUMEN

INTRODUCTION AND IMPORTANCE: Laryngeal Spindle Cell Carcinoma (SpCC), a rare subtype constituting only 0.5% of cases, poses diagnostic challenges due to its biphasic nature and histological resemblance to other neoplasms. Our study explores unique observations, including monoclonal epithelial origin and an unusually large tumor triggering respiratory distress. CASE REPORT: In this comprehensive case report, a 62-year-old male with a history of tuberculosis and extensive smoking presented with respiratory distress and a white vocal cord mass, diagnosed as spindle cell carcinoma (SpCC). Laryngoscopic and imaging evaluations revealed an ill-defined mass originating from the right supraglottic larynx. Histopathological examination and immunohistochemistry confirmed confirming the diagnosis. The management included immediate tracheostomy, surgical resection, adjuvant radiation therapy, and chemotherapy. Regular follow-ups and a multidisciplinary approach contributed to a successful three-year outcome without recurrence. CLINICAL DISCUSSION: Spindle Cell Carcinomas (SpCCs) of the larynx, historically termed carcinosarcoma and sarcomatoid carcinoma, are rare and predominantly affect middle-aged to elderly males. These biphasic tumors arise from both epithelial and spindle cell elements and present with symptoms like hoarseness and dysphagia. Risk factors include tobacco use, alcohol, and viral infections. Accurate diagnosis relies on histological and immunohistochemical analysis. Early detection facilitates favorable outcomes, with five-year survival rates ranging from 65 to 95%. CONCLUSION: Spindle Cell Carcinoma (SpCC) of the larynx, originating from epithelial and spindle cell elements, requires early detection through histological and immunohistochemical analysis. Early diagnosis leads to a notably optimistic five-year survival prognosis.

2.
ACS Appl Mater Interfaces ; 16(19): 25090-25100, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38709646

RESUMEN

The selective electrocatalytic reduction of nitrobenzene (NB) to aniline demands a desirable cathodic catalyst to overcome the challenges of the competing hydrogen evolution reaction (HER), a higher overpotential, and a lower selectivity. Here, we deposit Co-doped 1T MoS2 on Ti mesh by the solvothermal method with different doping percentages of Co as x % Co-MoS2 (where x = 3, 5, 8, 10, and 12%). Because of the lowest overpotential, lower charge-transfer resistance, strong suppression of the competing HER, and higher electrochemical surface area, 8% Co-MoS2 achieves 94% selectivity of aniline with 54% faradaic efficiency. The reduction process follows first-order dynamics with a reaction coefficient of 0.5 h-1. Besides, 8% Co-MoS2 is highly stable and retains 81% selectivity even after 8 cycles. Mechanistic studies showed that the selective and exothermic adsorption of the nitro group at x % Co-MoS2 leads to a higher rate of NB reduction and higher selectivity of aniline. The aniline product is successfully removed from the solution by polymerization at FTO. This study signifies the impact of doping metal atoms in tuning the electronic arrangement of 1T-MoS2 for the facilitation of organic transformations.

3.
Chemosphere ; 352: 141434, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38401867

RESUMEN

Ionic liquids (ILs) are a class of liquid salts with characteristics such as a low melting point, an ionic nature, non-volatility, and tunable properties. Because of their adaptability, they have a significant influence in the field of fluorescence. This paper reviews the primary literature on the use of ILs in fluorescence sensing technologies. The kind of target material is utilized to classify the fluorescence sensors made with the use of ILs. They include using ILs as probes for metals, nitro explosives, small organic compounds, anions, and gases. The efficacy of an IL-based fluorescence sensor depends on the precise design to guarantee specificity, sensitivity, and a consistent reaction to the desired analyte. The precise method can differ depending on the chemical properties of the IL, the choice of fluorophore, and the interactions with the analyte. Overall, the viability of the aforementioned materials for chemical analysis is evaluated, and prospective possibilities for further development are identified.


Asunto(s)
Líquidos Iónicos , Líquidos Iónicos/química , Estudios Prospectivos , Iones , Aniones , Gases , Colorantes
4.
Int J Surg Case Rep ; 116: 109342, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342030

RESUMEN

INTRODUCTION AND IMPORTANCE: Central giant cell tumor (CGCT) of bone is an uncommon yet locally aggressive neoplasm originating from undifferentiated mesenchymal cells in bone marrow. This case report explores a rare presentation in the maxilla extending to the mandible, emphasizing the complexity of CGCT management and the need for a multidisciplinary approach. CASE PRESENTATION: A 35-year-old female presented with a progressively enlarging non-tender, firm swelling on the left maxilla and a similar mandibular swelling. Paraesthesia of the left lower lip and chin accompanied the mandibular swelling. CT scans and 3D reconstructions revealed expansive osteolytic defects affecting the maxilla and mandible. Biochemical tests supported a central giant cell tumor diagnosis. Histopathology confirmed spindle cell proliferation and multinucleated giant cells in both lesions. Surgical intervention involved excision and reconstruction. A five-month follow-up showed no recurrence, affirming the treatment's success. CLINICAL DISCUSSION: Central giant cell tumors (CGCTs) of bone are primarily benign, arising from undifferentiated mesenchymal cells. While mostly benign, they carry a rare potential for malignancy. Diagnosis involves imaging (CT, MRI, bone scintigraphy) and confirmation through biopsy. Surgical resection is the standard treatment, with radiotherapy considered in challenging cases. Recurrence rates vary with the extent of surgical intervention. Alternative treatments like cryotherapy and chemotherapy show varying success. CONCLUSION: This case emphasizes the necessity of precise histopathological diagnosis for CGCT management. The intricate nature of maxillary involvement, coupled with mandibular association, mandates a multidisciplinary approach. Surgery, while the primary treatment, should be judiciously determined based on tumor characteristics and recurrence.

5.
Int J Surg Case Rep ; 111: 108894, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37812957

RESUMEN

INTRODUCTION AND IMPORTANCE: Lobular capillary hemangioma (LCH) is a benign vascular lesion typically affecting the head and neck region, especially the nasal cavity. However, its occurrence in the nasal cavity of the pediatric population is rare, making its diagnosis and management crucial in such cases. CASE PRESENTATION: A 7-year-old female presented with left-sided nasal obstruction and recurrent epistaxis for 4 months. Examination revealed a dark purplish-red nasal mass, which bled easily upon probing. CT scans showed a soft tissue lesion with post-contrast enhancement. Histopathological examination confirmed lobular capillary hemangioma. The patient successfully underwent surgical excision without pre-operative embolization. CLINICAL DISCUSSION: LCH affects both the skin and mucous membranes. Although its exact etiology remains debated, trauma is a leading risk factor for its development. Biopsy and radiological investigations confirm its diagnosis. Differentiating LCH from other vascular disorders with similar presentations is essential for a thorough understanding and better management. Endoscopic surgical excision combined with electrodesiccation is the treatment of choice. CONCLUSION: Intranasal LCH in children is infrequent. An accurate diagnosis is essential for a comprehensive understanding. Surgical excision with electrodesiccation is the preferred treatment, but the role of pre-operative embolization is still under discussion.

6.
Chemosphere ; 307(Pt 4): 135846, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35952790

RESUMEN

The hazardous nature of certain azeotropic mixtures has urged the researchers to explore the separation techniques which can impart a contamination free environment. Despite of causing environmental concerns, these azeotropic mixtures are responsible for causing serious health issues to humans and animals. More specifically, in this article, we have taken Tetrahydrofuran (THF) - water azeotropic mixture into consideration. It has been reported that it affects the central nervous system, liver, as well as can cause carcinogenicity. To be more precise, in this article, two different entrainers has been evaluated on their merits of exploiting liquid-liquid phase envelope for separating Tetrahydrofuran-water binary azeotropic mixture. The process flow sheet schematic with n-octane as entrainer (having two distillation regions) has a reduced operating energy requirement by 21.11% while comparing with the Residue Curve Map of n-hexane as entrainer having three distillation regions. The total capital cost for THF-water-n-octane case has been found to be 7.1 $/y × 105 and that of THF-water-n-hexane case has been found to be 9 $/y × 105. However, in both of the cases, the product purity of 99.9% has been achieved for THF. Also, the classical trade-off between capital cost and energy cost has been shown in this study. The salient feature of this work is the use of dynamic simulation to understand the effect of recycle flow rate induced process operational in-feasibility due to distillation region shift.


Asunto(s)
Destilación , Agua , Animales , Análisis Costo-Beneficio , Destilación/métodos , Furanos , Hexanos , Humanos , Octanos
7.
Adv Exp Med Biol ; 1370: 445-460, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35882818

RESUMEN

Lead (Pb2+) is a developmental neurotoxicant that disrupts the GABA-shift and subsequently causes alterations in the brain's excitation-to-inhibition (E/I) balance. Taurine is a well-established neuroprotective and inhibitory compound for regulating brain excitability. Since mechanistically taurine can facilitate neuronal inhibition through the GABA-AR, the present study examined the anxiolytic potential of taurine derivatives. Treatment groups consisted of the following developmental Pb2+-exposures: Control (0 ppm) and Perinatal (150 ppm or 1,000 ppm lead acetate in the drinking water). Rats were scheduled for behavioral tests between postnatal days (PND) 36-45 with random drug assignments to either saline, taurine, or taurine-derived compound (TD-101, TD-102, or TD-103) to assess the rats' responsivity to each drug in mitigating the developmental Pb2+-exposure and anxiety-like behaviors through the GABAergic system. Long-Evans hooded rats were assessed using an open field (OF) test for preliminary locomotor assessment. Twenty-four hours later, the same rats were exposed to the elevated plus maze (EPM) and were given an i.p. injection of 43 mg/Kg of the saline, taurine, or TD drugs 15 min prior to testing. Each rat was tested using the triple-blind random assignment method for each drug condition. The OF data revealed that Control female rats had increased locomotor activity over Control male rats, and the Pb2+-exposed males and females had increased locomotor activity when compared to the Control male and female rats. However, in the EPM, the Control female rats exhibited more anxiety-like behaviors over Control male rats, and the Pb2+-exposed male and female rats showed selective responsivity to TD drugs when compared to taurine. For Pb2+-exposed males, TD-101 showed consistent recovery of anxiety-like behaviors similar to that of taurine regardless of Pb2+ dose, whereas in Pb2+-exposed females TD-101 and TD-103 showed greater anxiolytic responses in the EPM. The results from the present psychopharmacological study suggests that taurine and its derivatives are interesting drug candidates to explore sex-specific mechanisms and actions of taurine and the associated GABAergic receptor properties by which these compounds alleviate anxiety as a potential behavioral pharmacotherapy for neurodevelopmental Pb2+ exposure.


Asunto(s)
Ansiolíticos , Animales , Femenino , Masculino , Embarazo , Ratas , Ansiolíticos/farmacología , Ansiolíticos/uso terapéutico , Ansiedad/inducido químicamente , Ansiedad/tratamiento farmacológico , Ácido gamma-Aminobutírico , Plomo/toxicidad , Ratas Long-Evans , Taurina/farmacología , Taurina/uso terapéutico
8.
RSC Adv ; 12(3): 1682-1693, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35425209

RESUMEN

This study reports the synthesis, characterization, and mercuric ion detection ability of novel tribenzamides having flexible and rigid moieties. N-{4-[2-(1,3-Benzoxazolyl)]phenyl}-3,5-N,N'-bis(4-alkyloxybenzoyl)benzamides (TBa-TBc) were synthesized from newly synthesized diamine, N-(1,3-benzoxazol-2-yl-phenyl)-3,5-diaminobenzamide (BODA) and p-alkoxybenzoic acids (p-ABA) by amidation reaction. Structural characterization of the synthesized compounds was done through spectroscopic techniques (FT-IR and NMR). The synthesized tribenzamides along with silver nanoparticles were used for modification of a glassy carbon electrode. Square wave anodic stripping voltammetry was carried out to test the performance of the modified electrode for mercuric ion detection. The designed sensor was found to demonstrate the qualities of sensitivity, selectivity, reproducibility and anti-interference ability. The sensing platform helped in detecting femtomolar concentrations of mercuric ions which are much below the level declared toxic by the World Health Organization.

9.
ChemSusChem ; 15(3): e202102596, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-34927792

RESUMEN

The gram-scale selective oxidation of biomass-based chemicals, in particular 5-hydroxymethylfurfural (HMF), into value-added 2,5-diformylfuran (DFF) has a high application potential but suffers from high cost, low selectivity, and harsh reaction conditions. Besides, the electrooxidation strategy requires the usage of expensive electrodes and struggles with low selectivity and efficiency, which restricts its further scaled-up application. In this regard, a continuous-flow system was developed through redox mediator I- /I2 for the efficient synthesis of DFF, which could accelerate the mass transfer of I- (I2 ) to aqueous (organic) phase and avoid over-oxidation to achieve high selectivity. After the solvent system, iodine concentration, and reaction time were optimized, highly efficient DFF synthesis (selectivity >99 %) could be achieved in the electrochemical flow system using inexpensive graphite felt (GF) as electrode. Moreover, selective HMF oxidation was paired with the hydrogen evolution reaction with increased efficiency after using in-situ-loaded GF-CoS2 /CoS and GF-Pt electrodes. As a result, the required energy to achieve the gram-scale synthesis of DFF was significantly reduced, demonstrating outstanding potential for large-scale production of the target product.


Asunto(s)
Furanos , Biomasa , Catálisis , Oxidación-Reducción
10.
Nanotechnology ; 32(48)2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34425561

RESUMEN

SnO2is widely used for ethanol-sensing applications due to its excellent physicochemical properties, low toxicity and high sensitivity. However it is a challenge to construct 3D-hierarchical structures with sub 5 nm primary grain particle, which is the optimized size for ethanol sensor. Herein, genetic tri-level hierarchical SnO2microstructures are synthesised by the genetic conversion of 3D hierarchical SnS2flowers assembled by ultrathin nanosheets. The SnS2nanosheets are morphology genetic converted to porous nanosheets with sub 5 nm SnO2nanoparticles during the calcination process. When used for the detection of ethanol, the sensor exhibits a high sensitivity of 0.5 ppm (Ra/Rg = 6.8) and excellent gas-sensing response (Ra/Rg= 183 to 100 ppm) with short response/recovery time (12 s/11 s). The excellent gas sensing performance is much better than that of the previous reported SnO2-based sensors. The highly sensitivity is attributed to the large surface area derived from the recrystallization and volume changes, which offers more active sites during the morphology genetic conversion from SnS2to SnO2. Furthermore, the flower-like 3D structure enhances the stability of the materials and is beneficial for the mass diffusion dynamics of ethanol.

11.
Nanomicro Lett ; 13(1): 54, 2021 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-34138199

RESUMEN

Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase (SEI) and consume electrolyte. In this article, γ-glycidoxypropyl trimethoxysilane (GOPS) was incorporated in Si/PEDOT:PSS electrodes to construct a flexible and conductive artificial SEI, effectively suppressing the consumption of electrolyte. The optimized electrode can maintain 1000 mAh g-1 for nearly 800 cycles under limited electrolyte compared with 40 cycles of the electrodes without GOPS. Also, the optimized electrode exhibits excellent rate capability. The use of GOPS greatly improves the interface compatibility between Si and PEDOT:PSS. XPS Ar+ etching depth analysis proved that the addition of GOPS is conducive to forming a more stable SEI. A full battery assembled with NCM 523 cathode delivers a high energy density of 520 Wh kg-1, offering good stability.

12.
Drug Dev Ind Pharm ; 47(3): 477-483, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33621153

RESUMEN

Background: Organ transplantation is an important and critical procedure, which requires the suppression of immunity, and to suppress the immunity, a constant plasma concentration of immunosuppressant is required.Objectives: The said objective can be achieved by formulating a controlled release drug delivery system of the drug. Chitosan (CHT) nanoparticles (NPs) have been revolutionizing the conventional drug delivery system, for the past two decades. The aim of the current research work was to develop and evaluate CHT-based mycophenolate mofetil (MMF) loaded nanoparticles (CHT/MMF-NPs) using different drug to polymer ratios.Methods: The challenge was to entrap a lipophilic drug within NPs by the ionic gelation method of the positively charged CHT, using tripolyphosphate (TPP) as the crosslinking agent. The prepared CHT/MMF-NPs were evaluated for physical and chemical characterizations, including particle size, surface charge, entrapment efficiency (EE), surface morphology by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) for chemical compatibilities, X-ray diffractometry (XRD) and in-vitro dissolution studies.Results: Outcomes of the studies revealed that particles were 260 ± 17 nm in diameter, with the smooth and regular surface. Satisfactory values of EE (99%) have indicated the suitability of selected ingredients and employed methodology. Moreover, FTIR has confirmed the chemical compatibilities of the formulations. In-vitro dissolution studies have indicated diffusion type of controlled and sustained drug release during 24 h, with zero-order, as best fit kinetic model.Conclusion: Conclusively, the successful achievement of objectives has indicated the suitability of excipients and methodology to prepare CHT/MMF-NPs for better therapeutic outcomes.


Asunto(s)
Quitosano , Nanopartículas , Quitosano/metabolismo , Preparaciones de Acción Retardada , Portadores de Fármacos , Liberación de Fármacos , Ácido Micofenólico , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier
13.
Water Sci Technol ; 83(1): 1-25, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33460403

RESUMEN

Cryptosporidium spp. are one of the most important waterborne pathogens worldwide and a leading cause of mortality from waterborne gastrointestinal diseases. Detection of Cryptosporidium spp. in water can be very challenging due to their low numbers and the complexity of the water matrix. This review describes the biology of Cryptosporidium spp. and current methods used in their detection with a focus on C. parvum and C. hominis. Among the methods discussed and compared are microscopy, immunology-based methods using monoclonal antibodies, molecular methods including PCR (polymerase chain reaction)-based assays, and emerging aptamer-based methods. These methods have different capabilities and limitations, but one common challenge is the need for better sensitivity and specificity, particularly in the presence of contaminants. The application of DNA aptamers in the detection of Cryptosporidium spp. oocysts shows promise in overcoming these challenges, and there will likely be significant developments in aptamer-based sensors in the near future.


Asunto(s)
Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Animales , Cryptosporidium/genética , Oocistos , Agua
14.
ACS Appl Mater Interfaces ; 12(45): 50388-50396, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33108718

RESUMEN

The NaTi2(PO4)3 (NTP) anode materials exhibit high Na+ diffusion dynamics; carbon-based materials can effectively improve its limited electronic conductivity. However, the low Na+ diffusion of NTP/C composite materials from inhomogeneous carbon mixing or uncontrollable carbon coating cannot keep up with fast electron transfer, leading to undesirable electrochemical performances. Herein, a uniform and controllable carbon layer is designed on the self-supported-coated NTP nanorod arrays with binder-free (NTP@C NR) to improve Na+ and electron kinetics simultaneously. As a result, the NTP@C NR electrodes possess initial coulombic efficiency (ICE = 97%), good rate capabilities (89.1 mA h g-1 at 100 C), and stability with ≈78.4% of capacity retention rate at even 30 C over 1200 cycles. The sodium-ion capacitors with NTP@C NR as an anode and commercially activated carbon as a cathode exhibit ∼9180.0 W kg-1 of power density at 10 A g-1 and super high retention of ≈94.5% at 1 A g-1 over 7000 cycles. This work will help balance transport kinetics between the ion and electron for materials applied in storage devices.

15.
Int J Nanomedicine ; 15: 5603-5612, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32848390

RESUMEN

INTRODUCTION: Organ transplantation is a critically important procedure, which requires immune modulation by using immunosuppressants. Development of nanoparticles is an emerging and beneficial engineering process to increase the dissolution rate of poorly soluble immunosuppressants as well as to provide controlled release for better therapeutic outcomes. METHOD: Currently, the nanoprecipitation method was employed to fabricate ß-cyclodextrin (ßCD) facilitated mycophenolate mofetil (MMF)-loaded solid lipid nanoparticles (SLNPs). The prime objectives of the study included, improvement of the dissolution profile of poorly aqueous soluble drug and controlled release from the SLNs to provide steady state drug concentration. Drug release from the prepared SLNs was assessed in two different media, ie, acidic buffer at pH 1.2 and phosphate buffer at pH 7.2 using USP dissolution apparatus for 12 h, followed by the evaluation of drug release mechanism and pattern by applying kinetic models. RESULTS: Justifiably, in acidic medium, the release was found to be 12% more (68%) in comparison to that in basic medium (56%). However, in both dissolution media, drug release was independent of initial concentration (R2>0.95) with non-Fickian type of diffusion mechanism. The outcomes of the study have exhibited that prepared formulations were in nanosized range (80-170 nm) with a net charge of ±23 charge on their surface. They possessed fairly uniform surface with acceptable polydispersity index (0.23±0.09). Scanning electron microscopy (SEM) analysis illustrated that the nanoparticles had uniform particle size and shape. DISCUSSION: The findings show potential applications of the nanoparticles and the method for the development of SLNPs in controlled release of MMF for better therapeutic outcomes. Conclusively, the prepared SLNPs were well designed in nanosized ranges and justifying the once daily controlled release formulation dose of MMF to enhance patient compliance.


Asunto(s)
Portadores de Fármacos/química , Inmunosupresores/farmacocinética , Ácido Micofenólico/farmacocinética , Nanopartículas/química , Disponibilidad Biológica , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Difusión , Portadores de Fármacos/farmacocinética , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Concentración de Iones de Hidrógeno , Inmunosupresores/química , Lípidos/química , Microscopía Electrónica de Rastreo , Ácido Micofenólico/química , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Solubilidad , beta-Ciclodextrinas/química
16.
ACS Appl Mater Interfaces ; 12(17): 19431-19438, 2020 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-32255340

RESUMEN

PEDOT: PSS has been studied as a silicon-based binder due to its inherent superior electricity and electrochemical stability. However, it cannot effectively alleviate the huge volume changes of silicon during lithiation/delithiation due to its linear structure, resulting in poor cycling stability. Ion-cross-linking is a usual method to cross-link linear polymers into 3D structures. In this paper, multivalent cations of the 5th period and Group 2 cross-linked PEDOT:PSS were applied as silicon anode binders and studied systematically. It was found that the variation trend of viscosity and conductivity of PEDOT:PSS after cross-linking was consistent with that of ionic potential and softness parameters of multivalent cations. The mesostructure of a binder after cross-linking is influenced by the solubility product constant of sulfites or hydroxides of cations and the growth characteristics of crystals. An Sn4+-cross-linked binder displayed increased viscosity and electrical conductivity and higher reduced modulus and hardness due to its positive softness parameter and higher ion potential. The Si electrode with the Sn4+-cross-linked binder showed improved cycling stability (1876.4 mAh g-1 compared with 1068.4 mAh g-1 of the electrode with the pure PEDOT:PSS binder after 100 cycles) and superior rate capability (∼800 mAh g-1 at an ultrahigh current density of 8.0 A g-1).

17.
J Colloid Interface Sci ; 565: 270-277, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31978789

RESUMEN

Developing conductive polymer binders is a new way to enhance the electric connectivity and mechanical contact of Si based anode material. While the linear structure of commercial PEDOT:PSS cannot effectively alleviate the volume expansion of Si. Herein, glycerol was introduced as a cross-linker to PEDOT:PSS binder for Si anodes, which can further improve the interfacial compatibility between silicon and PEDOT:PSS. After crosslinking, the peel force increased 2 times. As a result, the Si nanoparticles anode with the glycerol-crosslinked binder exhibited a high reversible capacity of 1951.5 mAh g-1 after 200 cycles at 0.5 A g-1 and superior rate capability (804 mAh g-1 at a high current of 8.0 A g-1) for the inherent superior conductivity of PEDOT:PSS.

18.
Can J Microbiol ; 65(11): 851-857, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31404505

RESUMEN

Environmentally stable and disinfectant-resistant oocysts of Cryptosporidium spp. shed in the feces of infected humans and animals frequently contaminate water resources and are subsequently spread via potable and recreational waters. The current monoclonal-antibody-based methods for detecting them in water are slow, labor-intensive, and demand skills to interpret the results. We have developed DNA-aptamer-based aptasensors, coupled with magnetic beads, to detect and identify the oocysts of C. parvum for monitoring recreational and drinking water sources. A sensitive and specific electrochemical aptasensor (3'-biotinylated R4-6 aptamer) was used as a secondary ligand to bind the streptavidin-coated magnetic beads. This was incorporated into a probe using gold nanoparticle modified screen-printed carbon electrodes. Square wave voltammetry allowed for specific recognition of C. parvum oocysts. The aptamer-coated probes had an oocyst detection limit of 50. It did not bind to the cysts of Giardia duodenalis, another common waterborne pathogen, thus indicating its high specificity for the target pathogen. The system could successfully detect C. parvum oocysts in spiked samples of the raw lake and river waters. Therefore, the combined use of the aptasensor and magnetic beads has the potential to monitor water quality for C. parvum oocysts in field samples without relying on monoclonal antibodies and skill-demanding microscopy.


Asunto(s)
Aptámeros de Nucleótidos/genética , Cryptosporidium parvum/aislamiento & purificación , Agua Potable/parasitología , Magnetismo/métodos , Ríos/parasitología , Animales , Cryptosporidium parvum/clasificación , Cryptosporidium parvum/genética , Oro/química , Humanos , Magnetismo/instrumentación , Nanopartículas del Metal/química , Oocistos/clasificación , Oocistos/genética , Oocistos/aislamiento & purificación , Sensibilidad y Especificidad , Recursos Hídricos
19.
Adv Exp Med Biol ; 1155: 801-819, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31468449

RESUMEN

Lead (Pb2+) is a developmental neurotoxicant that causes alterations in the brain's excitation-to-inhibition (E/I) balance. By increasing chloride concentration through GABA-ARs, taurine serves as an effective inhibitory compound for maintaining appropriate levels of brain excitability. Considering this pharmacological mechanism of taurine facilitated inhibition through the GABA-AR, the present pilot study sought to explore the anxiolytic potential of taurine derivatives. Treatment groups consisted of the following developmental Pb2+-exposures: Control (0 ppm) and Perinatal (150 ppm or 1000 ppm lead acetate in the drinking water). Rats were scheduled for behavioral tests between postnatal days (PND) 36-45 with random assignments to either solutions of Saline, Taurine, or Taurine Derived compounds (i.e., TD-101, TD-102, or TD-103) to assess the rats' responsiveness to each drug in mitigating the developmental Pb2+-exposure through the GABAergic system. Long Evans Hooded rats were assessed using an Open Field (OF) test for preliminary locomotor assessment. Approximately 24-h after the OF, the same rats were exposed to the Elevated Plus Maze (EPM) and were given an i.p. injection of 43 mg/Kg of the Saline, Taurine, or TD drugs 15-min prior to testing. Each rat was tested using the random assignment method for each pharmacological condition, which was conducted using a triple-blind procedure. The OF data revealed that locomotor activity was unaffected by Pb2+-exposure with no gender differences observed. However, Pb2+-exposure induced an anxiogenic response in the EPM, which interestingly, was ameliorated in a gender-specific manner in response to taurine and TD drugs. Female rats exhibited more anxiogenic behavior than the male rats; and as such, exhibited a greater degree of anxiety that were recovered in response to Taurine and its derivatives as a drug therapy. The results from the present psychopharmacological pilot study suggests that Taurine and its derivatives could provide useful data for further exploring the pharmacological mechanisms and actions of Taurine and the associated GABAergic receptor properties by which these compounds alleviate anxiety as a potential behavioral pharmacotherapy for treating anxiety and other associated mood disorders.


Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Plomo/efectos adversos , Exposición Materna/efectos adversos , Taurina/farmacología , Animales , Femenino , Masculino , Proyectos Piloto , Embarazo , Efectos Tardíos de la Exposición Prenatal , Distribución Aleatoria , Ratas , Ratas Long-Evans
20.
Adv Exp Med Biol ; 1155: 821-846, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31468450

RESUMEN

Lead (Pb2+) is a developmental neurotoxicant that causes lifelong cognitive dysfunctions. In particular, Pb2+-induced frontoexecutive dysfunctions emerge later in life when the cortex is fully myelinated, thereby permitting the ability to assess the extent to which Pb2+ has developmentally impacted higher order cognitive and behavioral systems. The present study evaluated the effects of developmental Pb2+-exposure (150 ppm lead acetate in the drinking water) in Long Evans Hooded rats through the Attention Set-Shift Test (ASST) between postnatal days (PND) 60-90. Treatment groups were comprised of Control (0 ppm), Perinatal (150 ppm), and Perinatal+Taurine (150 ppm + 0.05% Taurine in the drinking water) rats (N = 36; n = 6 per treatment group for each sex). Frontoexecutive functions were evaluated based on trials-to-criterion (TTC) and errors-to-criterion (ETC) measures for simple and complex discriminations (SD & CD), intradimensional and extradimensional shifts (ID & ED), as well as reversals (Rev) of the CD, I-, and ED stages, respectively. Post-testing, the prelimbic (PrL), infralimbic (IL), orbital ventral frontal (OV), orbital ventro-lateral (OVL), and hippocampal (HP) brain regions were extracted and processed through Liquid Chromatography/Mass Spectrophotometry (LC/MS) for determining the GABA and Taurine ratios relative to Glutamate, Dopamine, Norepinephrine, Epinephrine, and Serotonin. The ASST data revealed that Perinatal rats are negatively impacted by developmental Pb2+-exposures evidenced by increased TTC and ETC to learn the SD, ID, and ID-Rev with unique sex-based differences in frontoexecutive dysfunctions. Moreover, Perinatal+Taurine co-treated rats exhibited a recovery of the frontoexecutive dysfunctions observed in Perinatal rats to levels equivalent to Control rats across both sexes. The LC/MS data revealed altered brain sub-region specific patterns across the PrL, IL, OV, OVL, and HP in response to developmental Pb2+-exposure that produced an altered neurochemical signaling profile in a sex-dependent manner, which may underlie the observed frontoexecutive dysfunctions, cognitive inflexibility, and associated motivation deficits. When taurine co-treatment was administered concurrently for the duration of developmental Pb2+-exposure, the observed frontoexecutive dysfunctions were significantly reduced in both ASST task performance and neurochemical ratios that were comparable to Control levels for both sexes. Altogether, the data suggest that taurine co-treatment may facilitate neuroprotection, mitigate neurotransmitter excitability balancing, and perhaps ameliorate against neurotoxicant exposures in early development as a potential psychopharmacotherapy.


Asunto(s)
Atención , Función Ejecutiva , Plomo/efectos adversos , Exposición Materna/efectos adversos , Taurina/farmacología , Animales , Femenino , Aprendizaje , Masculino , Fármacos Neuroprotectores/farmacología , Embarazo , Ratas , Ratas Long-Evans
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