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1.
Chemosphere ; 340: 139719, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37549746

RESUMO

Toxic and carcinogenic metal (loid)s, such arsenic (As) and cadmium (Cd), found in contaminated paddy soils pose a serious danger to environmental sustainability. Their geochemical activities are complex, making it difficult to manage their contamination. Rice grown in Cd and As-polluted soils ends up in people's bellies, where it can cause cancer, anemia, and the deadly itai sickness. Solving this issue calls for research into eco-friendly and cost-effective remediation technology to lower rice's As and Cd levels. This research delves deeply into the origins of As and Cd in paddy soils, as well as their mobility, bioavailability, and uptake mechanisms by rice plants. It also examines the current methods and reactors used to lower As and Cd contamination in rice. Iron-modified biochar (Fe-BC) is a promising technology for reducing As and Cd toxicity in rice, improving soil health, and boosting rice's nutritional value. Biochar's physiochemical characteristics are enhanced by the addition of iron, making it a potent adsorbent for As and Cd ions. In conclusion, Fe-BC's biomembrane properties make them an attractive option for remediating As- and Cd-contaminated paddy soils. More efficient mitigation measures, including the use of biomembrane technology, can be developed when sustainable agriculture practices are combined with these technologies.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Humanos , Cádmio/análise , Ferro/química , Arsênio/análise , Solo/química , Oryza/química , Medição de Risco , Poluentes do Solo/análise
2.
Int J Biol Macromol ; 236: 123988, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36907299

RESUMO

This study aimed to develop a robust approach for the early diagnosis and treatment of tumors. Short circular DNA nanotechnology synthesized a stiff and compact DNA nanotubes (DNA-NTs) framework. TW-37, a small molecular drug, was loaded into DNA-NTs for BH3-mimetic therapy to elevate the intracellular cytochrome-c levels in 2D/3D hypopharyngeal tumor (FaDu) cell clusters. After anti-EGFR functionalization, the DNA-NTs were tethered with a cytochrome-c binding aptamer, which can be applied to evaluate the elevated intracellular cytochrome-c levels via in situ hybridization (FISH) analysis and fluorescence resonance energy transfer (FRET). The results showed that DNA-NTs were enriched within the tumor cells via anti-EGFR targeting with a pH-responsive controlled release of TW-37. In this way, it initiated the triple inhibition of "BH3, Bcl-2, Bcl-xL, and Mcl-1". The triple inhibition of these proteins caused Bax/Bak oligomerization, leading to the perforation of the mitochondrial membrane. This led to the elevation of intracellular cytochrome-c levels, which reacted with the cytochrome-c binding aptamer to produce FRET signals. In this way, we successfully targeted 2D/3D clusters of FaDu tumor cells and achieved the tumor-specific and pH-triggered release of TW-37, causing tumor cell apoptosis. This pilot study suggests that anti-EGFR functionalized, TW-37 loaded, and cytochrome-c binding aptamer tethered DNA-NTs might be the hallmark for early tumor diagnosis and therapy.


Assuntos
Neoplasias Hipofaríngeas , Nanotubos , Humanos , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Neoplasias Hipofaríngeas/tratamento farmacológico , Medicina de Precisão , Projetos Piloto , Citocromos c/metabolismo , DNA
3.
J Colloid Interface Sci ; 608(Pt 2): 1792-1801, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34742088

RESUMO

The activity of photocatalytic CO2 conversion to carbon-containing products is determined by the adsorption and activation of CO2 molecules on the surface of catalyst. Here, iron doped porous CeO2 with oxygen vacancy (PFeCe) was prepared by one-step combustion method. The amount of CO2 adsorbed via using the porous structure has been significantly increased in the case of a relatively small specific surface area and CO2 molecules are more easily captured and undergo a reduction reaction with photoinduced carriers. In addition, oxygen vacancies are formed in the iron doped CeO2 lattice as the active sites for CO2 reduction, which can form strong interactions with CO2 molecules, thereby effectively activating CO2 molecules. The reduction products of CO2 over PFeCe composite are CO and CH4, which is approximately 9.0 and 7.7 folds than that of CeO2. This work offers insights for the construction of efficient ceria-based photocatalysts to further achieve robust solar CO2 conversion.

4.
Semin Ophthalmol ; 36(7): 531-540, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33780299

RESUMO

Background: von Hippel-Lindau (VHL) syndrome is a multisystem neoplastic disorder involving eyes, central nervous system, kidneys, spine, and other tissues. A retinal capillary hemangioma (RCH) is the earliest manifestation of the VHL disease in most cases.Areas covered:This paper aims to provide an up-to-date review of the current literature about von Hippel-Lindau syndrome. Molecular background, systemic and ocular features of the diseases as well as the utility of newer imaging modalities in diagnosis and monitoring of ocular VHL disease have been described. Besides, we have discussed newer treatment modalities and therapeutic targets.Conclusion: Modern imaging technologies like optical coherence tomography and optical coherence tomography angiography are tools of the trade, in making an appropriate diagnosis and monitoring disease activity and response to treatment. Peripheral RCH may be treated using laser photocoagulation in tumors up to 3000 µm. Vascular endothelial growth factor suppression can help in reducing tumor activity and stabilize the tumor size; however, it does not regress the RCH.


Assuntos
Hemangioblastoma , Neoplasias da Retina , Doença de von Hippel-Lindau , Humanos , Neoplasias da Retina/diagnóstico , Neoplasias da Retina/terapia , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular , Doença de von Hippel-Lindau/complicações
5.
Environ Sci Pollut Res Int ; 27(23): 28730-28736, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32462622

RESUMO

For several decades air pollution has been recognized to hit drastically the skin of human body. Air pollutants predominantly accountable for aging, oxidative damage, and inflammatory allergic reactions led to psoriasis, dermatitis, acne, and skin cancer owing to the impaired functions of DNA, proteins, and lipid biomolecules. Elevated air pollution and its detrimental effects along with variations in physiological parameters of the skin are verily the scaffold for anti-pollution assertions and could be recognized as markers. The present article encompasses the salient features of air pollution and UV radiations besides dreadful effects on human skin physiological parameters and some anti-pollution approaches.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Energia Solar , Humanos , Pele/química , Raios Ultravioleta
6.
Pak J Pharm Sci ; 33(6): 2521-2526, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33867325

RESUMO

The purpose of this investigation was to evaluate the vicissitudes in polyphenolic extract- based high internal phase creams (HIPCs) and effect of storage temperature dependent characteristics. Rheological parameters, that is, power law and IPC analysis with its physical characteristics were exploredat different storage temperatures (8°, 25°, 40° and 40° with 75% relative humidity- RH) with different time intervals up to 2 months of newly formulated poly-phenolic extract- based high internal phase cream and its comparison with base. Polyphenolic- based HIPCs showed non-Newtonian-pseudo plastic tendencies in vicissitudes with time and storage temperatures. Data analysis with Power Law and IPC paste was found to fit to all the rheograms. Flow index, shear sensitivity factor, consistency Index and 10 RPM of freshly prepared HIPCs with and without encapsulated polyphenolic extract were found to be 0.5,0.53, 386.4 cP, and 432.9 cP, respectively.The viscosities were fallen with rise in shear stress.There was no change in color, electrical conductivity, liquefaction and phase separation after centrifugation in any sample of polyphenolic extract-based HIPCs and its base. Polyphenolic- based extract HIPCs behaved non-Newtonian- pseudo plastic tendencies and showed stability up to 2 months and can be directed absolutely to shield skin against ultraviolet radiation (UV) intervened oxidative mutilation.


Assuntos
Extratos Vegetais/química , Polifenóis/química , Creme para a Pele/química , Antioxidantes/química , Cannabis/química , Reologia , Temperatura , Viscosidade
7.
Pak J Pharm Sci ; 32(2): 709-720, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31081787

RESUMO

Enzymes are biological catalyst involve in different biochemical reactions. But over activation of these biomolecules can cause disease thus different inhibitors and knockout therapies are use in current clinical practice. Carbonic anhydrases (CAs), a group of ubiquitously expressed metalloenzymes, are involved in numerous physiological and pathological processes, including gluconeogenesis, lipogenesis, ureagenesis, tumorigenicity and the growth and virulence of various pathogens. In addition to the established role of CA inhibitors (CAIs) as diuretics and antiglaucoma drugs, it has recently emerged that CAIs could have potential as novel anti-obesity, anticancer and anti-infective drugs. Furthermore, recent studies suggest that CA activation may provide a novel therapy for Alzheimer's disease. This article discusses the biological rationale for the novel uses of inhibitors or activators of CA activity in multiple diseases, and highlights progress in the development of specific modulators of the relevant CA isoforms, some of which are now being evaluated in clinical trials.


Assuntos
Anti-Infecciosos/farmacologia , Fármacos Antiobesidade/farmacologia , Antineoplásicos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Diuréticos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Animais , Anti-Infecciosos/química , Anti-Infecciosos/uso terapêutico , Fármacos Antiobesidade/química , Fármacos Antiobesidade/uso terapêutico , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/uso terapêutico , Diuréticos/química , Diuréticos/uso terapêutico , Glaucoma/tratamento farmacológico , Humanos , Simulação de Acoplamento Molecular , Obesidade/tratamento farmacológico , Osteoporose/tratamento farmacológico
8.
J Cosmet Sci ; 69(4): 257-267, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30311901

RESUMO

Glutathione reduced (GSH) is the mother of all the antioxidants and has an antimelanogenic effect. It is extremely vulnerable to oxidation in the solution form which limits its use. The GSH in nano-oil droplets present a potential solution to this problem. The aim of this study was to formulate glutathione-loaded nanoemulsion and assess its stability studies over a 90-day testing period. To formulate GSH-loaded nanoemulsion pseudo-ternary phase diagram, it was built with various concentrations of water, liquid paraffin oil, and surfactant mixture (Tween 80 and Span 80). The oily phase was prepared by dissolving the GSH (450 mg) in liquid paraffin oil through stirring. High-energy homogenization was used to prepare the nanoemulsion. From preformulation stability studies of the 28-day testing period, nanoemulsion (NE-19) with oil and surfactant mixture ratio (1:1) of hydrophilic lipophilic balance (HLB) value 10 was selected. The samples of NE-19 and its respective base (B-19) were kept at four different storage conditions for a period of 90 days and evaluated for physical characteristics, droplet size and distribution analysis, zeta potential analysis, electrical conductivity, mobility, polydispersity, pH, phase separation, and flow analysis at different time intervals. Glutathione in nano-oil droplets with nonionic surfactants produced oil-in-water nanoemulsions that were thermodynamically stable over the 90-day testing period at different storage conditions. NE-19 was formulated having non-Newtonian flow and pseudo-plastic behavior. pH was found in the range of 5-6. Polydispersity was less than 0.3. The droplet size of fresh nanoemulsion was 96.05 nm, whereas the zeta potential was -37.1. Mobility and electrical conductivity were -2.726 µm cm/Vs and 0.0141 mS/cm, respectively. Glutathione-loaded nanoemulsions have excellent stability, promising the solution in nano-oil droplets and are suggested for in-vivo release studies for oxidative skin related diseases.


Assuntos
Emulsões/química , Glutationa/química , Nanopartículas/química , Estabilidade de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Oxirredução , Parafina/química , Tensoativos/química , Fatores de Tempo
9.
J Phys Chem B ; 122(32): 7797-7810, 2018 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-30036486

RESUMO

Two new nonconjugated porphyrin-coumarin dyads with different orientations with respect to donor-acceptor entities and their zinc complexes were synthesized. Single-crystal structures of the free-base porphyrin-coumarin dyads were successfully resolved. The absorption spectra of the dyads were linear combinations of the spectra of their corresponding monomers, indicating a negligible electronic communication between the coumarin and porphyrin moieties. However, the fluorescence emission of the coumarin entity in all of the dyads was quenched significantly compared to that of pristine coumarin, and this effect was attributed to intramolecular energy transfer from the coumarin to the porphyrin. The energy transfer kinetics from the coumarin to the porphyrin was shown to be fast ( kFörster = 1.13 × 1013 s-1 for the ortho-isomer and 5.13 × 1011 s-1 for the para-isomer in DMF) and efficient (transfer efficiency ca. 96-97%). Transient absorption studies showed that the excited state decay process (S2 → S1*, S1* → S1, S1 → S0, and S1 → T1) of the para-isomer was faster than that of the ortho-isomer in DMF. All of the synthesized dyads were tested for their interactions with ct-DNA and photocleavage activity toward PBR322-DNA. The results revealed that all of the dyads interacted with ct-DNA via only an external groove-binding mode; the binding constants were calculated to be 3.24 × 105 (3a), 3.05 × 105 (3b), 3.04 × 105 (4a), and 4.88 × 105 (4b), and the photocleavage activity was in the order 4b < 3b < 4a < 3a. Furthermore, only the zinc complexes of the porphyrin-coumarin dyads could be absorbed by tumor cells (A549). These complexes were mainly localized in the cytoplasm, exhibited red fluorescence, and showed low cytotoxicity toward all of the tumor cell lines tested. The results showed that these zinc complexes of the porphyrin-coumarin dyads have potential applications in fluorescence imaging.


Assuntos
Cumarínicos/química , Porfirinas/química , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Complexos de Coordenação/farmacologia , DNA/química , DNA/metabolismo , Clivagem do DNA/efeitos dos fármacos , Transferência de Energia , Humanos , Conformação Molecular , Plasmídeos/química , Plasmídeos/metabolismo , Teoria Quântica , Oxigênio Singlete/metabolismo , Espectrometria de Fluorescência , Zinco/química
10.
J Membr Biol ; 249(4): 419-28, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26895317

RESUMO

The DNA-binding, photocleavage, and antitumor activity of three free base pyridyl corroles 1, 2, and 3 have been investigated. The binding affinity toward CT-DNA decreases with increasing number of pentafluorophenyl, whereas the photocleavage activity toward pBR322 DNA becomes more efficient. Singlet oxygen was demonstrated as active species responsible for DNA cleavage. These corroles exhibited high cytotoxicity against three tested cancer cells (Hela, HapG2, and A549) and the cytotoxicity could be further enhanced under irradiation. Intracellular reactive oxygen species level was also monitored using HeLa Cells upon the combined treatment of corroles and light. These corroles could be absorbed by HeLa cells at low concentration. They can induce the decrease of mitochondrial membrane potential and apoptosis of tumor cells under irradiation.


Assuntos
Clivagem do DNA/efeitos dos fármacos , Clivagem do DNA/efeitos da radiação , DNA/metabolismo , Luz , Porfirinas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Humanos , Concentração Inibidora 50 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Porfirinas/química , Espécies Reativas de Oxigênio/metabolismo
11.
World J Hepatol ; 2(11): 406-9, 2010 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-21173909

RESUMO

Although the presence of hepatic portal venous gas (HPVG) on computed tomography (CT) is typically an ominous finding, HPVG may sometimes be less catastrophic. The clinical significance of HPVG is variable, and it depends primarily on the underlying pathology. We report a case of a patient with acquired immunodeficiency syndrome (AIDS) who was found to have HPVG on CT as a presumed result of gastrointestinal cryptosporidiosis, an association that, to our knowledge, has not been reported. This case illustrates another cause of HPVG that should be considered in patients with AIDS.

12.
Hand (N Y) ; 5(4): 374-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22131918

RESUMO

Radiological changes have been described in de Quervain's disease of the wrist. The author analyzed the clinical data of 114 patients who reported to the orthopedic clinic of a Regional Referral Hospital for a period of 4 years [2003 to 2007]. Radiographs of the wrist were available for 39 cases, of which 14 [35.89%] were found abnormal. Two patients with abnormal radiographs [14.28%] required surgery where as 7 out of 25 [28%] with normal radiographs were managed surgically. Radial styloid abnormality was not found statistically significant [p < 0.05], and the outcome of management was irrespective of the changes in the radial styloid.

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