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1.
Biomolecules ; 10(2)2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32092985

RESUMO

Cinnamomum verum plant extract mediated propellant chemistry route was used for the green synthesis of zinc oxide nanoparticles. Prepared samples were confirmed for their nano regime using advanced characterization techniques such as powder X-ray diffraction and microscopic techniques such as scanning electron microscopy and transmission electron microscopy. The energy band gap of the green synthesized zinc oxide (ZnO)-nanoparticles (NPs) were found between 3.25-3.28 eV. Fourier transmission infrared spectroscopy shows the presence of Zn-O bond within the wave number of 500 cm-1. SEM images show the specific agglomeration of particles which was also confirmed by TEM studies. The green synthesized ZnO-NPs inhibited the growth of Escherichia coli and Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 125 µg mL-1 and 62.5 µg mL-1, respectively. The results indicate the prepared ZnO-NPs can be used as a potential antimicrobial agent against harmful pathogens.

2.
Curr Pharm Des ; 26(7): 790-800, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31894743

RESUMO

Keeping in view the public health-related issues of Alzheimer's disease (AD), its unpredictable occurrence and progression indicate the needs for best treatment options. The present bioinformatics study explores the binding pattern and molecular interactions between human acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes with natural compounds from Bacopa monnieri. The docking analysis between natural compounds as a ligand and AChE, BuChE as a receptor was completed using MGL tools Autodock 4.2 module. The analysis of the hydrophobic interactions, inhibition constants, and hydrogen bonds may indicates that they play a significant role in finding out the interacting position at the active site. However, after analyzing the binding energy (ΔG), the documented data shows that bacoside X, bacoside A, 3-beta-D-glucosylstigmasterol and daucosterol could be good inhibitors in the inhibition of AChE and BuChE activities. Therefore, our study indicates that the inhibition constants of the aforesaid natural compounds of Bacopa can be utilized for the development of inhibitors.

3.
Curr Pharm Des ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31951164

RESUMO

In recent scenario, nanotechnology based therapeutics intervention has gained tremendous impetus all across the globe. Nano-based pharmacological intervention of various bioactive compounds has been explored on an increasing scale. Sesquiterpenes are major constituents of essential oils (EOs) present in various plant species which embodies intriguing therapeutic potentials. However, owing to their poor physico-chemical properties; they have pharmacological limitations. Recent advances in nano-based therapeutic interventions offer various avenues to improve their therapeutic applicability. Reckoning with these, the present review collates various nano-based therapeutic intervention of sesquiterpenes with prospective potential against various debilitating diseases especially cancer. In our viewpoint, considering the burgeoning advancement in the field of nanomedicine; in the near future, clinical applicability of these nano-formulated sesquiterpenes can be foreseen with great enthusiasm.

4.
Curr Pharm Des ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31951165

RESUMO

Nanoparticles (NPs) are unique may be organic, or inorganic, play a vital role in the development of drug delivery targeting the brain and central nervous system (CNS). Intranasal drug delivery has shown to be an efficient strategy and attractive application for drug delivery to the brain and CNS disorders and related diseases such as Parkinson's disease, Alzhemier's disease and brain solid tumors. Blood brain barrier (BBB) and blood cerebrospinal fluid barriers are natural protective hindrances to enter any drug molecules into the CNS and brain. Nanoparticles exhibit excellent intruding capacity for therapeutic agents and overcome the risk of protective barriers. By using nanotechnology based NPs targeting drug delivery can be improved across BBB and to discharge drugs in a controlled manner. NPs confer safe from degradation phenomenon. Several kinds of NPs are used for nose to brain (N2B) enroute such as lipidemic nanoparticles, polymeric nanoparticles, inorganic NPs, solid lipid NPs, dendrimers. Among them, popular lipidemic and polymeric NPs are discussed, and their participation in anti-cancer activity have also been highlighted in this review.

5.
Int J Nanomedicine ; 14: 4667-4679, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308652

RESUMO

Purpose: The pathogenicity in Candida spp was attributed by several virulence factors such as production of tissue damaging extracellular enzymes, germ tube formation, hyphal morphogenesis and establishment of drug resistant biofilm. The objective of present study was to investigate the effects of silver nanoparticles (AgNPs) on growth, cell morphology and key virulence attributes of Candida species. Methods: AgNPs were synthesized by the using seed extract of Syzygium cumini (Sc), and were characterized by UV-Vis spectrophotometer, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and transmission electron microscopy (TEM). ScAgNPs were used to evaluate their antifungal and antibacterial activity as well as their potent inhibitory effects on germ tube and biofilm formation and extracellular enzymes viz. phospholipases, proteinases, lipases and hemolysin secreted by Candida spp. Results: The MICs values of ScAgNPs were ranged from 0.125-0.250 mg/ml, whereas the MBCs and MFCs were 0.250 and 0.500 mg/ml, respectively. ScAgNPs significantly inhibit the production of phospholipases by 82.2, 75.7, 78.7, 62.5, and 65.8%; proteinases by 82.0, 72.0, 77.5, 67.0, and 83.7%; lipase by 69.4, 58.8, 60.0, 42.9, and 65.0%; and hemolysin by 62.8, 69.7, 67.2, 73.1, and 70.2% in C. albicans, C. tropicalis, C. dubliniensis, C. parapsilosis and C. krusei, respectively, at 500 µg/ml. ScAgNPs inhibit germ tube formation in C. albicans up to 97.1% at 0.25 mg/ml. LIVE/DEAD staining results showed that ScAgNPs almost completely inhibit biofilm formation in C. albicans. TEM analysis shows that ScAgNPs not only anchored onto the cell surface but also penetrated and accumulated in the cytoplasm that causes severe damage to the cell wall and cytoplasmic membrane. Conclusion: To summarize, the biosynthesized ScAgNPs strongly suppressed the multiplication, germ tube and biofilm formation and most importantly secretion of hydrolytic enzymes (viz. phospholipases, proteinases, lipases and hemolysin) by Candia spp. The present research work open several avenues of further study, such as to explore the molecular mechanism of inhibition of germ tubes and biofilm formation and suppression of production of various hydrolytic enzymes by Candida spp.


Assuntos
Antifúngicos/farmacologia , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Nanopartículas Metálicas/química , Prata/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida/citologia , Candida/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Proteínas Hemolisinas/metabolismo , Humanos , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Syzygium/química , Virulência/efeitos dos fármacos , Fatores de Virulência
6.
Biomolecules ; 9(12)2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888262

RESUMO

The development of advanced glycation end-products (AGEs) inhibitors is considered to have therapeutic potential in diabetic complications inhibiting the loss of the biomolecular function. In the present study, zinc oxide nanoparticles (ZnO-NPs) were synthesized from aqueous leaf extract of Morus indica and were characterized by various techniques such as ultraviolet (UV)-Vis spectroscopy, Powder X-Ray Diffraction (PXRD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Further, the inhibition of AGEs formation after exposure to ZnO-NPs was investigated by in-vitro, in-vivo, and molecular docking studies. Biochemical and histopathological changes after exposure to ZnO-NPs were also studied in streptozotocin-induced diabetic rats. ZnO-NPs showed an absorption peak at 359 nm with a purity of 92.62% and ~6-12 nm in size, which is characteristic of nanoparticles. The images of SEM showed agglomeration of smaller ZnO-NPs and EDS authenticating that the synthesized nanoparticles were without impurities. The biosynthesized ZnO-NPs showed significant inhibition in the formation of AGEs. The particles were effective against methylglyoxal (MGO) mediated glycation of bovine serum albumin (BSA) by inhibiting the formation of AGEs, which was dose-dependent. Further, the presence of MGO resulted in complete damage of biconcave red blood corpuscles (RBCs) to an irregular shape, whereas the morphological changes were prevented when they were treated with ZnO-NPs leading to the prevention of complications caused due to glycation. The administration of ZnO-NPs (100 mg Kg-1) in streptozotocin(STZ)-induced diabetic rats reversed hyperglycemia and significantly improved hepatic enzymes level and renal functionality, also the histopathological studies revealed restoration of kidney and liver damage nearer to normal conditions. Molecular docking of BSA with ZnO-NPs confirms that masking of lysine and arginine residues is one of the possible mechanisms responsible for the potent antiglycation activity of ZnO-NPs. The findings strongly suggest scope for exploring the therapeutic potential of diabetes-related complications.

7.
Semin Cancer Biol ; 2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31891780

RESUMO

Breast cancer is one of the most prevalent and reoccurring cancers and the second most common reason of death in women. Despite advancements in therapeutic strategies for breast cancer, early tumor recurrence and metastasis in patients indicate resistance to chemotherapeutic medicines, such as paclitaxel due to the abnormal expression of ER and EGF2 in breast cancer cells. Therefore, the development of alternatives to paclitaxel is urgently needed to overcome challenges involving drug resistance. An increasing number of studies has revealed miRNAs as novel natural alternative substances that play a crucial role in regulating several physiological processes and have a close, adverse association with several diseases, including breast cancer. Due to the therapeutic potential of miRNA and paclitaxel in cancer research, the current review focuses on the differential roles of various miRNAs in breast cancer development and treatment. miRNA delivery to a specific target site, the development of paclitaxel and miRNA formulations, and nanotechnological strategies for the delivery of nanopaclitaxel in the management of breast cancer are discussed. These strategies involve improving the cellular uptake and bioavailability and reducing the toxicity of free paclitaxel to achieve accumulation tumor site. Furthermore, a molecular docking study was performed to ascertain the enhanced anticancer activity of the nanoformulation of ANG1005 and Abraxane. An in silico analysis revealed that ANG1005 and Abraxane nanoformulations have superior and significantly enhanced interactions with the proteins α-tubulin and Bcl-2. Therefore, ANG1005 and Abraxane may be more suitable in the therapeutic management of breast cancer than the existing free paclitaxel. miRNAs can revert abnormal gene expression to normalcy; since miRNAs serve as tumor suppressors. Therefore, restoration of particular miRNAs levels as a replacement therapy may be an effective endocrine potential strategy for treating ER positive/ negative breast cancers.

8.
PLoS One ; 13(12): e0208951, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30589842

RESUMO

The present study was aimed to develop a liposomal formulation of thymoquinone (Lip-TQ) to treat Candida albicans infection in diabetic mice. Streptozotocin (STZ) was injected to induce hyperglycemia and on day 3 post STZ administration, mice were intravenously infected with C. albicans. Various doses (2, 5 and 10 mg/kg) of Free or Lip-TQ were administered in C. albicans infected diabetic mice. The effect of Lip-TQ was also determined on the organ indices, liver and kidney function parameters. Lip-TQ at a dose of 10 mg/kg significantly reduced the level of the blood glucose and alleviated the systemic C. albicans infection in diabetic mice. C. albicans infected diabetic mice treated with Lip-TQ at a dose of 10 mg/kg showed the survival rate of 70% as compared to that of 20% in the group treated with free TQ. The treatment with Lip-TQ resulted in the recovery of the organ indices, liver inflammation, kidney functioning and pancreas regeneration in diabetic mice. Moreover, TQ formulations also showed the direct therapeutic effect against candidiasis in the untreated or metformin-treated diabetic mice. Therefore, the findings of the present study support the use of Lip-TQ in the treatment of candidiasis in the diabetic patients.


Assuntos
Benzoquinonas/administração & dosagem , Candidíase/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Lipossomos/administração & dosagem , Animais , Benzoquinonas/química , Glicemia , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Candidíase/complicações , Candidíase/microbiologia , Candidíase/patologia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/microbiologia , Diabetes Mellitus Experimental/fisiopatologia , Modelos Animais de Doenças , Humanos , Lipossomos/química , Fígado/efeitos dos fármacos , Fígado/microbiologia , Camundongos
9.
Nanomaterials (Basel) ; 8(8)2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30071582

RESUMO

The objective of the present study was one step extracellular biosynthesis of silver nanoparticles (AgNPs) using supernatant of Candida glabrata isolated from oropharyngeal mucosa of human immunodeficiency virus (HIV) patients and evaluation of their antibacterial and antifungal potential against human pathogenic bacteria and fungi. The mycosynthesized AgNPs were characterized by color visualization, ultraviolet-visible (UV) spectroscopy, fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The FTIR spectra revealed the binding and stabilization of nanoparticles with protein. The TEM analysis showed that nanoparticles were well dispersed and predominantly spherical in shape within the size range of 2⁻15 nm. The antibacterial and antifungal potential of AgNPs were characterized by determining minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC)/ minimum fungicidal concentration (MFC), and well diffusion methods. The MBC and MFC were found in the range of 62.5⁻250 µg/mL and 125⁻500 µg/mL, which revealed that bacterial strains were more susceptible to AgNPs than fungal strains. These differences in bactericidal and fungicidal concentrations of the AgNPs were due to the differences in the cell structure and organization of bacteria and yeast cells. The interaction of AgNPs with C. albicans analyzed by TEM showed the penetration of nanoparticles inside the Candida cells, which led the formation of "pits" and "pores" that result from the rupturing of the cell wall and membrane. Further, TEM analysis showed that Candida cells treated with AgNPs were highly deformed and the cells had shrunken to a greater extent because of their interaction with the fungal cell wall and membrane, which disrupted the structure of the cell membrane and inhibited the normal budding process due to the destruction and loss of membrane integrity and formation of pores that may led to the cell death.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30046333

RESUMO

Due to the great economic, health, and medicinal importance, Phoenix dactylifera seeds were chosen for the synthesis of silver nanoparticles (AgNPs) because of their ecofriendly, nonhazardous, cost effectiveness advancement over physical and chemical methods, as green methods are safe, one step, and simple and did not require any chemical reducing and stabilizing agents. The green synthesized AgNPs were characterized by UV-Vis spectroscopy, SEM, HR-TEM, and DLS. Further, the bactericidal activity of synthesized AgNPs against Methicillin-resistant Staphylococcus aureus (MRSA) was investigated by determining MIC/MBC, agar diffusion methods, and electron microscopy. TEM images of the so-formed AgNPs revealed that the NPs were spherical in shape, with a size range of 14-30 nm. The MIC and MBC of AgNPs for MRSA were found to be 10.67±0.94 and 17.33±1.89 µg/ml, respectively. The antibacterial activities were found to be increased with the increasing concentration of AgNPs. The zone of inhibition was greater (24mm) at highest concentrations (500µg/ml) of AgNPs, while smaller (11mm) at lowest concentrations (7.8µg/ml). The SEM images of treated MRSA cells showed wrinkled and damaged cell wall, indicating the disruption and disorganization of membrane. HR-TEM analysis exhibits extensive injury and complete disintegration of cell wall and membrane. Large translucent zones have been seen in the cytoplasm, due to either localized or complete separation of the cell membrane from the cell wall. Overall, these results indicate that green synthesized AgNPs should be considered as an effective treatment and prevention option for the medical devises related infections caused by deadly MRSA and other drug resistant pathogens.

11.
Curr Drug Metab ; 18(9): 814-830, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28093993

RESUMO

BACKGROUND: Bacteriocin have been tested as safe and effective alternative molecules over the currently used chemotherapeutic agents. Thus, being an important clinical significance, its screening and recovery methods along with its application are poorly described. Therefore, their screening, purification strategies and utilities must me extended. Thus, in this review, we, summarize potential application, various screening and purification methods used for recovery of bacteriocins. METHODS: To complete this review, many reviews and previously published reports were studied. We, concentrated on review question and exclusion and inclusion criteria. The quality of content was evaluated by the quality the quality contents evaluation method. The standard method is used to describe the useful contents of available resources and appraised. RESULTS: One hundred twenty research and review reports were used to complete this report. Sixty reports were used to make a collective information on screening and production of Bacteriocin Eighty two papers were used to explore the antimicrobial, therapeutic, diagnostic etc potentialities of bacteriocin in diverse field. The summarize form of data also presented in the form of tables and figures. This review describes the various methods and parameters that must be considered during the screening and purification methods. Moreover, the useful information is collected in regard represent it therapeutic potentialities in various fields for the welfare of human being. CONCLUSIONS: The conclusion of this review presented the significance of a fundamental framework for planning to understanding the basic requirement needed for fast, cost effective screening and purification of bacteriocins. The summered area of their utilities also helpful to extend the research field of bacteriocin. Thus, this report would be useful not only to scale up the screening and production strategies faster at economical rate, but also provides a platform to extend the research field of bacteriocin in many ways.


Assuntos
Antibacterianos , Bacteriocinas , Animais , Antibacterianos/administração & dosagem , Antibacterianos/classificação , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Bacteriocinas/administração & dosagem , Bacteriocinas/classificação , Bacteriocinas/farmacocinética , Bacteriocinas/farmacologia , Humanos
12.
Int J Antimicrob Agents ; 49(1): 1-11, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27773497

RESUMO

Due to the appearance of antibiotic resistance and the toxicity associated with currently used antibiotics, peptide antibiotics are the need of the hour. Thus, demand for new antimicrobial agents has brought great interest in new technologies to enhance safety. One such antimicrobial molecule is bacteriocin, synthesised by various micro-organisms. Bacteriocins are widely used in agriculture, veterinary medicine as a therapeutic, and as a food preservative agent to control various infectious and food-borne pathogens. In this review, we highlight the potential therapeutic and food preservative applications of bacteriocin.


Assuntos
Agricultura/métodos , Antibacterianos/metabolismo , Antibacterianos/uso terapêutico , Infecções Bacterianas/veterinária , Bacteriocinas/metabolismo , Bacteriocinas/uso terapêutico , Conservação de Alimentos/métodos , Animais , Infecções Bacterianas/tratamento farmacológico , Humanos
13.
Artigo em Inglês | MEDLINE | ID: mdl-27034694

RESUMO

Neem (Azadirachta indica) is a member of the Meliaceae family and its role as health-promoting effect is attributed because it is rich source of antioxidant. It has been widely used in Chinese, Ayurvedic, and Unani medicines worldwide especially in Indian Subcontinent in the treatment and prevention of various diseases. Earlier finding confirmed that neem and its constituents play role in the scavenging of free radical generation and prevention of disease pathogenesis. The studies based on animal model established that neem and its chief constituents play pivotal role in anticancer management through the modulation of various molecular pathways including p53, pTEN, NF-κB, PI3K/Akt, Bcl-2, and VEGF. It is considered as safe medicinal plants and modulates the numerous biological processes without any adverse effect. In this review, I summarize the role of Azadirachta indica in the prevention and treatment of diseases via the regulation of various biological and physiological pathways.

14.
CNS Neurol Disord Drug Targets ; 15(5): 624-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26996169

RESUMO

Alzheimer's disease (AD) is the most frequent cause of dementia, especially in the elderly. AD is the most common progressive neurodegenerative disorder, which involves the loss of structure and function of cholinergic neurons. Moreover, if these neuronal changes cannot be compensated, this may ultimately lead to neurodegenerative processes. Therefore, most of the drug therapies are based on the cholinergic hypothesis, which suggests that AD begins as a deficiency in the production of the neurotransmitter acetylcholine. In this context, many inhibitors play an important role in AD treatment among which acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) have more potential in the treatment process of AD. In this study, we selected tea polyphenols of green tea which are reported as AChE and BChE inhibitors used in the treatment of AD. The molecular docking results revealed that polyphenols exhibit interactions and inhibit by binding with AChE and BChE. The amount of energy to bind with AChE and BChE needed by Epigallocatechin-3-gallate was lowest at about -14.45 and -13.30 kcal/mol, respectively. All compounds showed binding energy values ranging between -14.45 to -9.75 kcal/mol for both types of enzymes. The present docking study suggests that tea polyphenols inhibit AChE as well as BChE and enhance the cholinergic neurotransmission by prolonging the time. However, AChE molecules remain in the synaptic cleft. In consideration to these findings, cholinesterase inhibitors are suggested as the standard drugs for the treatment of AD.


Assuntos
Acetilcolinesterase/metabolismo , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Compostos Fitoquímicos/farmacologia , Polifenóis/farmacologia , Chá , Acetilcolina/metabolismo , Acetilcolinesterase/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Sequência de Aminoácidos , Butirilcolinesterase/genética , Catequina/análogos & derivados , Catequina/metabolismo , Inibidores da Colinesterase/química , Humanos , Simulação de Acoplamento Molecular , Nootrópicos/química , Nootrópicos/farmacologia , Compostos Fitoquímicos/química , Polifenóis/química , Ligação Proteica , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
15.
Sci Rep ; 6: 20414, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26829907

RESUMO

Advanced glycation end-products (AGEs) resulting from non-enzymatic glycation are one of the major factors implicated in secondary complications of diabetes. Scientists are focusing on discovering new compounds that may be used as potential AGEs inhibitors without affecting the normal structure and function of biomolecules. A number of natural and synthetic compounds have been proposed as AGE inhibitors. In this study, we investigated the inhibitory effects of AgNPs (silver nanoparticles) in AGEs formation. AgNPs (~30.5 nm) synthesized from Aloe Vera leaf extract were characterized using UV-Vis spectroscopy, energy-dispersive X-ray spectroscopy (EDX), high resolution-transmission electron microscopy, X-ray diffraction and dynamic light scattering (DLS) techniques. The inhibitory effects of AgNPs on AGEs formation were evaluated by investigating the degree of reactivity of free amino groups (lysine and arginine residues), protein-bound carbonyl and carboxymethyl lysine (CML) content, and the effects on protein structure using various physicochemical techniques. The results showed that AgNPs significantly inhibit AGEs formation in a concentration dependent manner and that AgNPs have a positive effect on protein structure. These findings strongly suggest that AgNPs may play a therapeutic role in diabetes-related complications.


Assuntos
Produtos Finais de Glicação Avançada/antagonistas & inibidores , Química Verde , Nanopartículas Metálicas/química , Prata/administração & dosagem , Prata/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Difração de Raios X
16.
Environ Toxicol ; 31(8): 945-56, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25648600

RESUMO

Four-week-old mice, weighing about 25-35 g were divided into five groups (8 mice in each group): vehicle control, low- (0.5 g/kg), middle- (1 g/kg), high- (3 g/kg), and exceptionally high-dose (5 g/kg). After first and second weeks of intraperitoneal exposure to AgNPs, biochemical, histopathological, and electron microscopic ultrastructural changes were investigated. No significant changes were observed in SGOT and ALP levels after first week of exposure, while the level of SGPT significantly increased (p < 0.05) in 2nd week treated mice, indicating that inflammatory of liver might be induced by high-dose (3 and 5 g/kg) of AgNPs. No obvious changes were observed for UA and BUN in all groups of treated mice. However, significant (p < 0.05) decrease in CR level was noticed in all groups of treated mice only at high-dose (3 and 5 g/kg). No remarkable changes in lipid profile were observed. Light microscopic histopathological investigation shows that first week treatment had not perceptible effect on the cytoarchitecture on liver, kidney, and spleen; while, second week treatment had only sporadic mild effects on these organs. However, no ultrastructural electron microscopic changes were observed in liver, kidney, and spleen of mice treated with 0.5, 1, and 3 g/kg of AgNPs when sacrificed on first and second week; while, exceptionally high-dose (5 g/kg) of AgNPs resulted in slight nuclear chromatin condensation and irregularities in nuclear membrane. The results suggested that AgNPs could be well tolerated in mice when given intraperitoneally and no death has been found during the experiment in any groups of treated mice. Interestingly, significant (<0.05) decrease in glucose levels in all experiment group is suggestive of curious hypoglycemic role of AgNPs warranting further study to explore its possible therapeutic potential in hyperglycemic conditions as well as its mechanism of action at molecular level. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 945-956, 2016.


Assuntos
Rim/patologia , Fígado/patologia , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Baço/patologia , Animais , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Microscopia Eletrônica de Transmissão , Baço/efeitos dos fármacos
17.
Braz. j. infect. dis ; 19(1): 68-76, Jan-Feb/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741248

RESUMO

Epidemiological and molecular data on community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) are still scarce in both Egypt and Saudi Arabia. There is almost no data regarding methicillin resistant Staphylococcus aureus (MRSA) prevalence in both countries. This study was conducted to investigate the prevalence and molecular epidemiology of S. aureus and MRSA nasal carriage among outpatients attending primary health care centers in two big cities in both countries. A total of 206 nasal swabs were obtained, 103 swabs from each country. S. aureus isolates were characterized by antibiotic susceptibility, presence of mecA and PVL genes, SCCmec-typing and spa typing, the corresponding Multi locus sequence typing clonal complex was assigned for each spa type based on Ridom StaphType database. MRSA was detected in 32% of the Egyptian outpatients while it was found in 25% of the Saudi Arabian outpatients. All MRSA isolates belonged to SCCmec type V and IVa, where some isolates in Saudi Arabia remained nontypeable. Surprisingly PVL+ isolates were low in frequency: 15% of MRSA Egyptian isolates and 12% of MRSA isolates in Saudi Arabia. Two novel spa types were detected t11839 in Egypt, and t11841 in Saudi Arabia. We found 8 spa types among 20 isolates from Egypt, and 12 spa types out of 15 isolates from Saudi Arabia. Only two spa types t008 and t223 coexisted in both countries. Four clonal complexes (CC5, CC8, CC22, and CC80) were identified in both Egypt and Saudi Arabia. However, the data collected lacked a representation of isolates from different parts of each country as only one health center from each country was included, it still partially illustrates the CA-MRSA situation in both countries. In conclusion a set of control measures is required to prevent further increase in MRSA prevalence.


Assuntos
Humanos , Portador Sadio/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Cavidade Nasal/microbiologia , Atenção Primária à Saúde/estatística & dados numéricos , Antibacterianos/farmacologia , Estudos Transversais , DNA Bacteriano/genética , Egito , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Pacientes Ambulatoriais , Filogenia , Arábia Saudita , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética
18.
World J Microbiol Biotechnol ; 31(1): 153-64, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25304025

RESUMO

The high prevalence of extended-spectrum ß-lactamases (76.3 %) and metallo-ß-lactamases (7.3 %) amongst the bacteria Pseudomonas aeruginosa is a critical problem that has set forth an enormous therapeutic challenge. The suggested role of nanoparticles as next generation antibiotics, and inadequate information on antibacterial activity of aluminium oxide nanoparticles has led us to investigate the green synthesis of aluminium oxide nanoparticles (Al2O3 NPs) using leaf extracts of lemongrass and its antibacterial activity against extended-spectrum ß-lactamases and metallo-ß-lactamases clinical isolates of P. aeruginosa. The synthesized Al2O3-NPs were characterized by scanning electron microcopy, high resolution-transmission electron microscopy, atomic force microscopy, X-ray diffraction, Zeta potential, and differential light scattering techniques. The X-ray diffraction data revealed the average size of the spherical Al2O3-NPs as 34.5 nm. The hydrodynamic size in Milli Q water and Zeta potential were determined to be 254 nm and +52.2 mV, respectively. The minimal inhibitory concentration of Al2O3-NPs was found to be in the range of 1,600-3,200 µg/ml. Treatment at concentrations >2,000 µg/ml, resulted in complete growth inhibition of extended-spectrum ß-lactamases and metallo-ß-lactamases isolates. Scanning electron microcopy analysis revealed the clusters of nanoparticles attached to the bacterial cell surface, causing structural deformities in treated cells. High resolution-transmission electron microscopy analysis confirmed that nanoparticles crossed the cell membrane to become intracellular. The interaction of nanoparticles with the cell membrane eventually triggered the loss of membrane integrity, most likely due to intracellular oxidative stress. The data explicitly suggested that the synthesized Al2O3-NPs can be exploited as an effective bactericidal agent against extended-spectrum ß-lactamases, non-extended-spectrum ß-lactamases and metallo-ß-lactamases strains of P. aeruginosa, regardless of their drug resistance patterns and mechanisms. The results elucidated the clinical significance of Al2O3-NPs in developing an effective antibacterial therapeutic regimen against the multi-drug resistant bacterial infections. The use of leaf extract of lemongrass for the synthesis of Al2O3-NPs appears to be cost effective, nontoxic, eco-friendly and its strong antibacterial activity against multi-drug resistant strains of P. aeruginosa offers compatibility for pharmaceutical and other biomedical applications.


Assuntos
Óxido de Alumínio/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura , Extratos Vegetais/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Óxido de Alumínio/síntese química , Antibacterianos/síntese química , Membrana Celular/efeitos dos fármacos , Cymbopogon/enzimologia , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Difração de Raios X
19.
Braz J Infect Dis ; 19(1): 68-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25523075

RESUMO

Epidemiological and molecular data on community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) are still scarce in both Egypt and Saudi Arabia. There is almost no data regarding methicillin resistant Staphylococcus aureus (MRSA) prevalence in both countries. This study was conducted to investigate the prevalence and molecular epidemiology of S. aureus and MRSA nasal carriage among outpatients attending primary health care centers in two big cities in both countries. A total of 206 nasal swabs were obtained, 103 swabs from each country. S. aureus isolates were characterized by antibiotic susceptibility, presence of mecA and PVL genes, SCCmec-typing and spa typing, the corresponding Multi locus sequence typing clonal complex was assigned for each spa type based on Ridom StaphType database. MRSA was detected in 32% of the Egyptian outpatients while it was found in 25% of the Saudi Arabian outpatients. All MRSA isolates belonged to SCCmec type V and IVa, where some isolates in Saudi Arabia remained nontypeable. Surprisingly PVL(+) isolates were low in frequency: 15% of MRSA Egyptian isolates and 12% of MRSA isolates in Saudi Arabia. Two novel spa types were detected t11839 in Egypt, and t11841 in Saudi Arabia. We found 8 spa types among 20 isolates from Egypt, and 12 spa types out of 15 isolates from Saudi Arabia. Only two spa types t008 and t223 coexisted in both countries. Four clonal complexes (CC5, CC8, CC22, and CC80) were identified in both Egypt and Saudi Arabia. However, the data collected lacked a representation of isolates from different parts of each country as only one health center from each country was included, it still partially illustrates the CA-MRSA situation in both countries. In conclusion a set of control measures is required to prevent further increase in MRSA prevalence.


Assuntos
Portador Sadio/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Cavidade Nasal/microbiologia , Atenção Primária à Saúde/estatística & dados numéricos , Antibacterianos/farmacologia , Estudos Transversais , DNA Bacteriano/genética , Egito , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Pacientes Ambulatoriais , Filogenia , Arábia Saudita , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética
20.
Appl Biochem Biotechnol ; 174(1): 398-410, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25080376

RESUMO

Advanced glycation end products are major contributors to the pathology of diabetes, Alzheimer's disease, and atherosclerosis; accordingly, identification of antiglycation compounds is attracting considerable interest. In the present study, the inhibitory effect of gum arabic capped-silver nanoparticles on advanced glycation end products formation was monitored by several biophysical techniques. Silver nanoparticles were characterized by ultraviolet-visible, high-resolution transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Bovine serum albumin and methylglyoxal mixtures incubated with increasing concentrations of silver nanoparticles showed significant reductions in advanced glycation end product formation that were confirmed by ultraviolet-visible, fluorescence spectrometry, and high-performance liquid chromatography techniques. High-performance liquid chromatography showed decreased adduct formation of glycated protein in the presence of silver nanoparticles. The structural changes induced by silver nanoparticles were further confirmed by circular dichroism and Fourier transform infrared spectroscopy. Strong inhibition of advanced glycation end product formation was observed in the presence of elevated silver nanoparticles. The results of this study suggest that silver nanoparticles are a potent antiglycating agent.


Assuntos
Produtos Finais de Glicação Avançada/química , Goma Arábica/química , Nanopartículas Metálicas/química , Aldeído Pirúvico/química , Soroalbumina Bovina/química , Prata/química , Animais , Bovinos , Nanopartículas Metálicas/ultraestrutura , Oxirredução
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