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1.
Appl Microbiol Biotechnol ; 104(7): 3121-3131, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060693

RESUMO

Antibiotic resistance in pathogenic bacteria is a major health challenge, as Infectious Diseases Society of America (IDSA) has recognized that the past simply drugs susceptible pathogens are now the most dangerous pathogens due to their nonstop growing resistance towards conventional antibiotics. Therefore, due to the emergence of multi-drug resistance, the bacterial infections have become a serious global problem. Acute infections feasibly develop into chronic infections because of many factors; one of them is the failure of effectiveness of antibiotics against superbugs. Modern research of two-dimensional nanoparticles and biopolymers are of great interest to attain the intricate bactericidal activity. In this study, we fabricated an antibacterial nanocomposite consisting of representative two-dimensional molybdenum disulfide (2D MoS2) nanoparticles. Polyhydroxyalkanoate (PHA) and chitosan (Ch) are used to encapsulate MoS2 nanoparticles into their matrix. This study reports the in vitro antibacterial activity and host cytotoxicity of novel PHA-Ch/MoS2 nanocomposites. PHA-Ch/MoS2 nanocomposites were subjected to time-dependent antibacterial assays at various doses to examine their antibacterial activity against multi-drug-resistant Escherichia coli K1 (Malaysian Type Culture Collection 710859) and methicillin-resistant Staphylococcus aureus (MRSA) (Malaysian Type Culture Collection 381123). Furthermore, the cytotoxicity of nanocomposites was examined against spontaneously immortalized human keratinocyte (HaCaT) cell lines. The results indicated significant antibacterial activity (p value < 0.05) against E. coli K1 and MRSA. In addition, PHA-Ch/MoS2 showed significant host cytocompatibility (p < 0.05) against HaCaT cells. The fabricated PHA-Ch/MoS2 nanocomposites have demonstrated effective antibacterial activity against both Gram-positive and -negative bacteria and exhibited better biocompatibility. Finally, PHA-Ch/MoS2 nanocomposites are shown to be suitable for antibacterial applications and also hold potential for further biomedical studies. Graphical Abstract.

2.
Neurol Sci ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040791

RESUMO

BACKGROUND: During transcranial direct current stimulation (tDCS), the amount and distribution of current that reaches the brain depends on individual anatomy. Many progressive neurodegenerative diseases are associated with cortical atrophy, but the importance of individual brain atrophy during tDCS in patients with progressive atrophy, including primary progressive aphasia (PPA), remains unclear. OBJECTIVE: In the present study, we addressed the question whether brain anatomy in patients with distinct cortical atrophy patterns would impact brain current intensity and distribution during tDCS over the left IFG. METHOD: We developed state-of-the-art, gyri-precise models of three subjects, each representing a variant of primary progressive aphasia: non-fluent variant PPA (nfvPPA), semantic variant PPA (svPPA), and logopenic variant PPA (lvPPA). We considered two exemplary montages over the left inferior frontal gyrus (IFG): a conventional pad montage (anode over F7, cathode over the right cheek) and a 4 × 1 high-definition tDCS montage. We further considered whether local anatomical features, specifically distance of the cortex to skull, can directly predict local electric field intensity. RESULTS: We found that the differences in brain current flow across the three PPA variants fall within the distribution of anatomically typical adults. While clustering of electric fields was often around individual gyri or sulci, the minimal distance from the gyri/sulci to skull was not correlated with electric field intensity. CONCLUSION: Limited to the conditions and assumptions considered here, this argues against a specific need to adjust the tDCS montage for these patients any more than might be considered useful in anatomically typical adults. Therefore, local atrophy does not, in isolation, reliably predict local electric field. Rather, our results are consistent with holistic head anatomy influencing brain current flow, with tDCS producing diffuse and individualized brain current flow patterns and HD-tDCS producing targeted brain current flow across individuals.

3.
Nanotechnology ; 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32097901

RESUMO

Multi-walled Carbon Nanotubes (MWCNTs) are a contemporary class of nanoparticles that have a prominent thermal, electrical and mechanical properties. There have been numerous studies on the enhancement of thermophysical properties of nanofluids. However, there is only limited research on thermal and stability analysis of MWCNT nanofluids with various kinds of solvents or base fluids, namely Propylene glycol, Ethanol, Ethylene glycol, Polyethylene glycol, Methanol and water. This paper reports the enhancement of thermophysical properties and stability of MWCNTs with six different base fluids in the presence of Sodium dodecyl benzene sulfonate (SDBS) surfactant with a mass concentration of 0.5 wt.%. Thermal and dispersion stabilities were determined using a Thermogravimetric analyzer (TGA) and Zeta potential, along with a visual inspection method to evaluate the agglomeration or sedimentation of MWCNT nanoparticles over a period of one month. Ultraviolet-Visible Spectroscopy (UV-Vis) and Fourier transform infrared spectroscopy (FTIR) were utilized to identify the molecular components and light absorption of the formulated nanofluids at their maximum wavenumber (4500 cm-1) and wavelength (800 nm). In addition, thermophysical properties such as thermal conductivity, specific heat capacity, viscosity and density with a peak temperature of 200°C were also experimentally evaluated. The TGA results illustrated that MWCNT/Ethylene Glycol (EG) nanofluid achieved maximum thermal stability at 140°C and it revealed a maximum zeta potential value of -61.8 mV. Thus, ethylene glycol solution was found to be the best base liquid to homogenize with MWCNTs for acquiring an enhanced thermophysical property and a long-term stability.

4.
J Pak Med Assoc ; 70(Suppl 1)(2): S83-S88, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31981342

RESUMO

Technological progress has changed the landscape of surgical practice. Minimally invasive surgery (MIS) and percutaneous interventions (PC) are constantly replacing open procedures. This reduces hospital stay and allows quicker recovery. The application of MIS should follow the good medical practice dictum by Hippocrates i.e. "First do no harm". To remain abreast with new procedures, the medical personnel are required to update and enhance their knowledge and skill. To ensure safety, the innovations are rigorously tested and tried. The learning curve of MIS is shortened by simulator training and proctorship. Credentialing processes are in place to enhance safe delivery of care. Despite of all these measures MIS and PCI are associated with adverse effects. The purpose of this article is to overview the iatrogenic trauma associated with MIS and PCI in major surgical subspecialties.

5.
J Pak Med Assoc ; 70(Suppl 1)(2): S106-S109, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31981347

RESUMO

Blunt aortic injury is associated with significant mortality. A large number of patients lose their lives before reaching the hospital, those who survive half die within a day. Isthmus is the commonest site of aortic injury. Aortic injury is usually associated with other injuries of the body hence a multidisciplinary approach is required. For aortic transection the treatment options have evolved from proximal and distal aortic cross clamping and repair with distal perfusion technique using shunt or partial heart bypass (extracorporeal circulation) to endovascular stenting depending upon the available facilities andexpertise. Distal perfusion technique helps in avoiding paraplegia. We present our institutional experience of polytrauma associated with blunt aortic injuries managed with open surgical repair with distal perfusion using cardiopulmonary bypass.

6.
Pathogens ; 8(4)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31766722

RESUMO

T4 genotype Acanthamoeba are opportunistic pathogens that cause two types of infections, including vision-threatening Acanthamoeba keratitis (AK) and a fatal brain infection known as granulomatous amoebic encephalitis (GAE). Due to the existence of ineffective treatments against Acanthamoeba, it has become a potential threat to all contact lens users and immunocompromised patients. Metal nanoparticles have been proven to have various antimicrobial properties against bacteria, fungi, and parasites. Previously, different types of cobalt nanoparticles showed some promise as anti-acanthamoebic agents. In this study, the objectives were to synthesize and characterize the size, morphology, and crystalline structure of cobalt phosphate nanoparticles, as well as to determine the effects of different sizes of cobalt metal-based nanoparticles against A. castellanii. Cobalt phosphate octahydrate (CHP), Co3(PO4)2•8H2O, was synthesized by ultrasonication using a horn sonicator, then three different sizes of cobalt phosphates Co3(PO4)2 were produced through calcination of Co3(PO4)2•8H2O at 200 °C, 400 °C and 600 °C (CP2, CP4, CP6). These three types of cobalt phosphate nanoparticles were characterized using a field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analysis. Next, the synthesized nanoparticles were subjected to biological assays to investigate their amoebicidal, amoebistatic, anti-encystation, and anti-excystation effects against A. castellanii, as well as cell cytotoxicity. The overall results showed that 1.30 ± 0.70 µm of CHP microflakes demonstrated the best anti-acanthemoebic effects at 100 µg/mL, followed by 612.50 ± 165.94 nm large CP6 nanograins. However, amongst the three tested cobalt phosphates, Co3(PO4)2, the smaller nanoparticles had stronger antiamoebic effects against A. castellanii. During cell cytotoxicity analysis, CHP exhibited only 15% cytotoxicity against HeLa cells, whereas CP6 caused 46% (the highest) cell cytotoxicity at the highest concentration, respectively. Moreover, the composition and morphology of nanoparticles is suggested to be important in determining their anti-acathamoebic effects. However, the molecular mechanisms of cobalt phosphate nanoparticles are still unidentified. Nevertheless, the results suggested that cobalt phosphate nanoparticles hold potential for development of nanodrugs against Acanthamoeba.

7.
Antibiotics (Basel) ; 8(4)2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31600971

RESUMO

Infections due to multi-drug resistant bacteria are on the rise and there is an urgent need to develop new antibacterials. In this regard, a series of six functionally diverse new quinazolinone compounds were synthesized by a facile one-pot reaction of benzoic acid derivatives, trimethoxymethane and aniline derivatives. Three compounds of 3-aryl-8-methylquinazolin-4(3H)-one, and 3-aryl-6,7-dimethoxyquinazolin4(3H)-one were prepared and tested against multi-drug resistant bacteria. Furthermore, we determined whether conjugation with silver nanoparticles improved the antibacterial efficacy of these quinazolinone derivatives. The newly synthesized compounds were characterized by ultraviolet visible spectrophotometry (UV-vis), Zetasizer analysis, Fourier transform infrared spectroscopic methods (FT-IR), and scanning electron microscopy (SEM). Using bactericidal evaluation, effects were determined against selected Gram-negative and Gram-positive bacteria. Furthermore, cytotoxicity of nanoconjugates on human cells were determined. The UV-vis spectrum of silver nanoparticles conjugated quinazolinone displayed surface plasmon resonance band in the range of 400-470 nm, and the size of nanoparticles was detected to be in the range of 100-250 nm by dynamic light scattering (DLS). FT-IR study confirmed the stabilization of silver nanoparticles by the presence of diverse functional arayl on each compound. SEM further revealed the construction of spherical nanoparticles. Among the quinazolinone derivative tested, two compounds (QNZ 4, QNZ 6) conjugated with silver nanoparticles showed enhanced antibacterial activity against Escherichia coli K1, Streptococcus pyogenes, Klebsiella pneumoniae, B. cereus and P. aeruginosa as compared to the compounds.

8.
Ann Med Surg (Lond) ; 45: 110-112, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452878

RESUMO

Introduction: Pleural effusion is common in patient with coronary artery bypass grafting (CABG) usually due to heart failure in preoperative and trauma of surgery in postoperative patient. Tuberculous Pleural effusion is most common form of extra pulmonary Tuberculosis. Preoperatively Tuberculous pleural effusion in CABG patients has rarely been described in literature. Presentation of case: A 62 years old gentleman with ischemic heart disease was admitted for coronary artery bypass grafting surgery. Preoperative workup showed left sided pleural. Intraoperatively left sided turbid yellowish colour effusion with loculation was noted while harvesting left internal mammary artery. Loculation were broken down, effusion was drained and tissues were sent for microbiology and histopathology. CABG was performed smoothly. Microbiology of pleural tissue revealed Mycobacterium tuberculosis while histopathology showed chronic granulomatous inflammation. Patient was started on antituberculous therapy and remained well six months postoperatively. Conclusion: In developing countries even without any constitutional symptoms of Tuberculosis high index of suspicion for Tuberculosis should be made for patient with pleural effusion especially in cases of cardiac surgery as to prevent morbidity and mortality.

9.
Nanomaterials (Basel) ; 9(4)2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31010071

RESUMO

The present research focused on the fabrication of biocompatible polyhydroxyalkanoate, chitosan, and hexagonal boron nitride incorporated (PHA/Ch-hBN) nanocomposites through a simple solvent casting technique. The fabricated nanocomposites were comprehensively characterized by Fourier transform infrared spectroscope (FT-IR), field emission scanning electroscope (FESEM), and elemental mapping and thermogravimetric analysis (TGA). The antibacterial activity of nanocomposites were investigated through time-kill method against multi drug resistant (MDR) microbes such as methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) K1 strains. In addition, nanocomposites have examined for their host cytotoxicity abilities using a Lactate dehydrogenase (LDH) assay against spontaneously immortalized human keratinocytes (HaCaT) cell lines. The results demonstrated highly significant antibacterial activity against MDR organisms and also significant cell viability as compared to the positive control. The fabricated PHA/Ch-hBN nanocomposite demonstrated effective antimicrobial and biocompatibility properties that would feasibly suit antibacterial and biomedical applications.

10.
Mater Sci Eng C Mater Biol Appl ; 100: 388-395, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948075

RESUMO

Cobalt oxide nanocubes incorporated with reduced graphene oxide (rGO-Co3O4) was prepared by using simple one-step hydrothermal route. Crystallinity and structural characteristics of the nanocomposite were analyzed and confirmed using X-ray diffraction (XRD) and Raman analysis, respectively. The cubical shape of the Co3O4 nanostructures and the distribution of Co3O4 nanocubes on the surface of rGO sheets were identified through field emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDX) mapping analysis, respectively. Raman spectra depicted the presence of D and G bands for GO and rGO with different ID/IG values and thus confirmed the reduction of GO into rGO. The electrochemical study reflects that the rGO-Co3O4 nanocomposite shows good electrocatalytic activity in oxidation of depression biomarker serotonin (5-HT) in phosphate buffer (pH 7.2). The detection of 5-HT was carried out by using rGO-Co3O4 nanocomposite modified glassy carbon electrode under dynamic condition using amperometry technique with a linear range of 1-10 µM. The limit of detection and limit of quantification were calculated and found to be 1.128 and 3.760 µM, respectively with a sensitivity value of 0.133 µΑ·µM-1. The sensor showed selectivity in the presence of different interferent species such as ascorbic acid, dopamine and uric acid.


Assuntos
Carbono/química , Cobalto/química , Técnicas Eletroquímicas/métodos , Vidro/química , Grafite/química , Nanocompostos/química , Óxidos/química , Serotonina/análise , Catálise , Eletrodos , Nanocompostos/ultraestrutura , Oxirredução , Análise Espectral Raman , Difração de Raios X
11.
Case Rep Surg ; 2019: 3821767, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30993027

RESUMO

Retrosternal extension of goiter is one of the most common types of masses in the superior mediastinum. These types of goiters classically present with compressive symptoms such as dyspnea, dysphonia, dysphagia, or sleep apnea. Surgical treatment with a total thyroidectomy and complete removal of the intrathoracic portion of thyroid is the gold standard treatment. These cervicomediastinal lesions at times may not be continuous, and a sternotomy may be required for complete and safe excision of the mediastinal mass to achieve decompression of the surrounding structures and preventing the hemorrhagic complications if attempted from cervical incision. We present a summary of two cases that gave an initial impression of retrosternal extension of thyroid gland, however intraoperatively were found to be separately encapsulated and required sternotomy for its safe and complete excision.

12.
J Pharm Anal ; 9(2): 133-141, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31011470

RESUMO

1, 3, 4-Oxadiazole derivatives (4a-5f) were previously synthesized to investigate their anticancer properties. However, studies relating to their antioxidant potential and signal transducer and activator of transcription (STAT) inhibition have not been performed. We investigated previously synthesized 1, 3, 4-oxadiazole derivatives (4a-5f) for various radical scavenging properties using several in vitro antioxidant assays and also for direct inhibition of STAT3 through molecular docking. The data obtained from various antioxidant assays such as 2, 2,-diphenyl-1-picrylhydrazyl radical (DPPH), nitric oxide, hydrogen peroxide, and superoxide anion radical revealed that among all the derivatives, compound 5e displayed high antioxidant activities than the standard antioxidant L-ascorbic acid. Additionally, the total reduction assay and antioxidant capacity assay further confirmed the antioxidant potential of compound 5e. Furthermore, the molecular docking studies performed for all derivatives along with the standard inhibitor STX-0119 showed that binding energy released in direct binding with the SH2 domain of STAT3 was the highest for compound 5e (-9.91kcal/mol). Through virtual screening, compound 5e was found to exhibit optimum competency in inhibiting STAT3 activity. Compound 5e decreased the activation of STAT3 as observed with Western blot. In brief, compound 5e was identified as a potent antioxidant agent and STAT3 inhibitor and effective agent for cancer treatment.

13.
Int J Surg Case Rep ; 57: 25-27, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30877989

RESUMO

INTRODUCTION: Fungal empyema a rare cause of empyema thoracis is commonly associated with nosocomial infection or gastrointestinal disease with very high mortality. Its association with chronic pancreatitis is rarely been described. PRESENTATION OF CASE: We present a case of young male known alcoholic with chronic pancreatitis and cystgastrostomy who presented with dyspnea and fever. Thorough workup showed left sided amylase rich loculated pleural effusion. Culture grew candida albicans. Esophagogram carried out for any esophageal rupture turned out to be negative. Histopathology was negative for malignancy. Intraoperative left sided yellowish colour fluid was drained, Loculation broken and rind removed. No pleuro-peritoneal fistula could be identified. Postoperatively patient remained well and discharged on antifungal. CONCLUSION: No obvious cause of fungal empyema could be found except for pancreatico-pleural spread as suggested by amylase rich pleural effusion along with growth of candida spp. Hence in patient with chronic pancreatitis and cystgastrostomy pleural effusion should be evaluated for fungal infection to avoid morbidity and mortality and commence early treatment.

14.
J Inflamm Res ; 11: 389-396, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30464571

RESUMO

Purpose: The aim of this study was to evaluate CXCL10 as a biomarker for periodontitis by determining the CXCL10 levels in saliva, serum, and gingival crevicular fluid (GCF) samples from periodontally healthy control subjects and adult subjects with chronic periodontitis. Patients and methods: Adult patients seeking dental treatment at Umm Al-Qura University dental clinic underwent a complete periodontal examination, and saliva, serum, and GCF samples were collected. Subjects were classified as chronic periodontitis patients (n=31) if they have a periodontal probing depth (PD) of ≥4 mm and/or clinical attachment level (CAL) of ≥3 mm in >30% of the teeth. The control group (n=25) had PD ≤3 mm and/or CAL ≤2 mm. ELISA was performed to determine the concentration of CXCL10 in saliva, serum, and GCF samples. Student's t-test was carried out to evaluate the significant difference between different groups. Spearman's correlation test was used to analyze the relationship between the levels of CXCL10 and the clinical periodontal parameters. P-value of ≤0.05 was considered significant. Results: Significantly higher concentrations of CXCL10 were found in saliva and serum in chronic periodontitis patients as compared with the controls (272±60.4 pg/mL and 72±13.4 pg/mL vs 130±22.2 pg/mL and 44.08±4.5 pg/mL, P≤0.05). The CXCL10 levels in GCF were higher in the periodontitis group as compared with the control group (66.36±32.0 pg/mL and 44.56±17.5 pg/mL, respectively); the difference did not reach statistical significance (P≥0.05). Moreover, serum CXCL10 level was significantly higher in periodontitis patients with moderate to severe bone loss as compared with those with mild bone loss (71.05±4.7 pg/mL vs 54.8±7.7 pg/mL, P≤0.05). The serum CXCL10 levels were found to be related to CAL measurements (r=0.3, P=0.026), while the saliva CXCL10 levels were related to PD measurements (r=0.8, P=0.0007). Conclusion: CXCL10 is significantly increased in periodontitis subjects as compared with controls and could be used as a marker for periodontal disease.

15.
J Cell Biochem ; 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30206975

RESUMO

N-benzhydrylpiperazine and 1,3,4-oxadiazoles are pharmacologically active scaffolds which exhibits significant inhibitory growth effects against various cancer cells, however, antiproliferation effects and the underlying mechanism for inducing apoptosis for aforementioned scaffolds addressing HeLa cancer cells remains uncertain. In this study, N-benzhydrylpiperazine clubbed with 1,3,4-oxadiazoles (4a-4h) were synthesized, subsequently characterized using high resolution spectroscopic techniques and eventually evaluated for their antiproliferation potential by inducing apoptosis in HeLa cancer cells. The MTT assay screening results revealed that among all, compound 4d ( N-benzhydryl-4-((5-(4-aminophenyl)-1,3,4-oxadiazol-2-yl)methyl)piperazine) in particular, exhibited IC 50 value of 28.13 ± 0.21 µg/mL and significantly inhibited the proliferation of HeLa cancer cells in concentration-dependent manner. The in vitro anticancer assays for treated HeLa cells resulted in alterations in the cell morphology, reduction in colony formation, and inhibition of cell migration in concentration-dependent treatment. Furthermore, G2/M phase arrest, variations in the nuclear morphology, degradation of chromosomal DNA confirmed the ongoing apoptosis in treated HeLa cells. Increase in the expression of cytochrome C and caspase-3 confirmed the involvement of intrinsic mitochondrial pathway regulating the cell death. Also, elevation in reactive oxygen species level and loss of mitochondrial membrane potential signified that compound 4d induced apoptosis in HeLa cells by generating the oxidative stress. Therefore, compound 4d may act as a potent chemotherapeutic agent against human cervical cancer.

16.
Materials (Basel) ; 11(9)2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30201852

RESUMO

Many wounds are unresponsive to currently available treatment techniques and therefore there is an immense need to explore suitable materials, including biomaterials, which could be considered as the crucial factor to accelerate the healing cascade. In this study, we fabricated polyhydroxyalkanoate-based antibacterial mats via an electrospinning technique. One-pot green synthesized graphene-decorated silver nanoparticles (GAg) were incorporated into the fibres of poly-3 hydroxybutarate-co-12 mol.% hydroxyhexanoate (P3HB-co-12 mol.% HHx), a co-polymer of the polyhydroxyalkanoate (PHA) family which is highly biocompatible, biodegradable, and flexible in nature. The synthesized PHA/GAg biomaterial has been characterized by field emission scanning electron microscopy (FESEM), elemental mapping, thermogravimetric analysis (TGA), UV-visible spectroscopy (UV-vis), and Fourier transform infrared spectroscopy (FTIR). An in vitro antibacterial analysis was performed to investigate the efficacy of PHA/GAg against gram-positive Staphylococcus aureus (S. aureus) strain 12,600 ATCC and gram-negative Escherichia coli (E. coli) strain 8739 ATCC. The results indicated that the PHA/GAg demonstrated significant reduction of S. aureus and E. coli as compared to bare PHA or PHA- reduced graphene oxide (rGO) in 2 h of time. The p value (p < 0.05) was obtained by using a two-sample t-test distribution.

17.
Environ Sci Pollut Res Int ; 25(27): 27122-27132, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30022389

RESUMO

This work presents the synthesis of the novel silica-cyanopropyl functionalized magnetic graphene oxide (MGO/SiO2-CN) hybrid nanomaterial derived by sol-gel method as a cheap efficient magnetic sorbent for the removal of extremely hazardous lead ions from aqueous media. The integration of the magnetic property, the carbon substrate, and the nitrile (-C ≡ N) containing organic grafted silica matrix promoted the adsorption capability against lead ions along with its simple synthesis recovery and low cost. The prepared nanocomposite was comprehensively characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Adsorption of lead was found to be pH dependent because of the charged nature of both analyte and adsorbent surface. Adsorption experiments were conducted under the optimum conditions, and the obtained experimental data from atomic absorption spectroscopy were analyzed using the popular isothermal models namely Langmuir, Freundlich, and Dubinin-Radushkevich isotherms as well as kinetically studied and evaluated for adsorption standard free energy (E). The experimental results have demonstrated the enhanced adsorption capability of the proposed sorbent nanocomposite for lead ion removal with the maximum adsorption capacity of 111.11 mg/g at pH 5.0. The proposed mechanism of lead adsorption was mainly attributed to the complexation of lead positive ions with the grafted -C ≡ N bond. The synergistic effect of the combination of three components (i.e., the magnetic graphene oxide matrix, the triple bond containing organic moiety, and the inorganic porous silica framework) excelled the adsorption capability and proved to be a good candidate as adsorbent for the removal of lead ions.


Assuntos
Grafite/química , Chumbo/isolamento & purificação , Nanocompostos/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Íons , Cinética , Magnetismo , Microscopia Eletrônica de Varredura , Dióxido de Silício , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Nanosci Nanotechnol ; 18(5): 3248-3256, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442825

RESUMO

The present work highlights the facile synthesis of hydrophobic palm fatty acid functionalized Fe3O4 nanoparticles (MNP-FA) for the efficient removal of oils from the surface of water. An intense hydrophobic layer was introduced on the surface of Fe3O4 nanoparticles functionalized by the palm fatty acid obtained from the hydrolysis of palm olein. Scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), Energy dispersive X-ray spectroscopy (EDX) and water contact angle analysis (WCA) measurements were used to characterize the newly fabricated palm fatty acid adorned magnetic Fe3O4 nanoparticles (MNP-FA). The obtained results confirmed the successful synthesis of palm fatty acid-functionalized magnetic nanoparticles. Oil removal tests performed with MNP-FA revealed that this newly prepared material could selectively adsorb lubricating oil up to 3.5 times of the particles' weight while completely repelling water. The main parameters affecting the adsorption of oil i.e., sorption time, mass of sorbent and pH of water were optimized.

19.
Apoptosis ; 23(2): 113-131, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29349707

RESUMO

Piperazine scaffolds or 2-azetidinone pharmacophores have been reported to show anti-cancer activities and apoptosis induction in different types of cancer cells. However, the mechanistic studies involve in induction of apoptosis addressing these two moieties for human cervical cancer cells remain uncertain. The present study emphasizes on the anti-proliferating properties and mechanism involved in induction of apoptosis for these structurally related azoles derivatives in HeLa cancer cells. 1-Phenylpiperazine clubbed with 2-azetidione derivatives (5a-5h) were synthesized, characterized using various spectroscopic techniques and evaluated for their in-vitro anti-proliferative activities and induction of apoptosis. Further, we also evaluated oxidative stress generated by these synthetic derivatives (5a-5h). Cell viability studies revealed that among all, the compound N-(3-chloro-2-(3-nitrophenyl)-4-oxoazetidin-1-yl)-2-(4-phenylpiperazin-1-yl) acetamide 5e remarkably inhibited the growth of HeLa cells in a concentration dependent manner having IC50 value of 29.44 ± 1.46 µg/ml. Morphological changes, colonies suppression and inhibition of migration clearly showed the antineoplasicity in HeLa cells treated with 5e. Simultaneously, phosphatidylserine externalization, DNA fragmentation and cell-cycle arrest showed ongoing apoptosis in the HeLa cancer cells induced by compound 5e in concentration dependent manner. Additionally, generation of intracellular ROS along with the decrease in mitochondrial membrane potential supported that compound 5e caused oxidative stress resulting in apoptosis through mitochondria mediated pathway. Elevation in the level of cytochrome c and upregulation in expression of caspase-3 clearly indicated the involvement of the intrinsic pathway of programmed cell death. In brief; compound 5e could serve as a promising lead for the development of an effective antitumor agent.


Assuntos
Antineoplásicos/farmacologia , Azetidinas/farmacologia , Mitocôndrias/efeitos dos fármacos , Piperazina/farmacologia , Neoplasias do Colo do Útero/fisiopatologia , Antineoplásicos/síntese química , Antineoplásicos/química , Azetidinas/síntese química , Azetidinas/química , Caspase 3/genética , Caspase 3/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piperazina/análogos & derivados , Piperazina/síntese química , Espécies Reativas de Oxigênio/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
20.
J Pak Med Assoc ; 66(Suppl 3)(10): S5-S7, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27895340

RESUMO

In the current era grown up congenital heart disease (GUCH) patients undergoing surgical interventions are increasing. Most of the interventions in the developed countries are either complex or redo-operations in patients who had previously undergone repair, palliation or correction. However, in the developing countries most of the interventions are primary and corrective. This descriptive retrospective study comprised GUCH patients who underwent surgical intervention for congenital heart disease (CHD) at Aga Khan University Hospital, Karachi, from January 2006 to December 2015. A total of 195 patients had been treated surgically with a mean age of 31.0±13.5 years. Majority of the patients underwent surgical interventions for closure of atrial 109(55.3%) and ventricular 51(26.2%) septal defect. The most common complications were prolonged ventilation 16(8.1%). Overall mortality was 4(2.1%). GUCH in our practice is for primary procedure with simple diagnosis that should have been treated before reaching adulthood as is done in the developed countries.


Assuntos
Países em Desenvolvimento , Cardiopatias Congênitas/cirurgia , Adulto , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Hospitais Universitários , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
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