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1.
Sci Rep ; 13(1): 4515, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934146

RESUMO

In the present study, fabrications of two eco-friendly superhydrophobic/superoleophilic recyclable foamy-based adsorbents for oil/water mixture separation were developed. Hierarchically biomass (celery)-derived porous carbon (PC) and multi-walled carbon nanotube (MWCNT) were firstly synthesized and loaded on pristine melamine foam (MF) by the simple dip-coating approach by combining silicone adhesive to create superhydrophobic/superoleophilic, recyclable, and reusable three-dimensional porous structure. The prepared samples have a large specific surface area of 240 m2/g (MWCNT), 1126 m2/g (PC), and good micro-mesoporous frameworks. The water contact angle (WCA) values of the as-prepared foams, PC/MF and MWCNT/MF, not only were 159.34° ± 1.9° and 156.42° ± 1.6°, respectively but also had oil contact angle (OCA) of equal to 0° for a wide range of oils and organic solvents. Therefore, PC/MF and MWCNT/MF exhibited superhydrophobicity and superoleophilicity properties, which can be considered effective adsorbents in oil/water mixture separations. In this context, superhydrophobic/superoleophilic prepared foams for kind of different oils and organic solvents were shown to have superior separation performance ranges of 54-143 g/g and 46-137 g/g for PC/MF and MWCNT/MF, respectively, suggesting a new effective porous material for separating oil spills. Also, outstanding recyclability and reusability of these structures in the ten adsorption-squeezing cycles indicated that the WCA and sorption capacity has not appreciably changed after soaking into acidic (pH = 2) and alkaline (pH = 12) as well as saline (3.5% NaCl) solutions. More importantly, the reusability and chemical durability of the superhydrophobic samples made them good opportunities for use in different harsh conditions for oil-spill cleanup.

2.
Adv Sci (Weinh) ; 10(36): e2304289, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37908147

RESUMO

As it is now established that global warming and climate change are a reality, international investments are pouring in and rightfully so for climate change mitigation. Carbon capture and separation (CCS) is therefore gaining paramount importance as it is considered one of the powerful solutions for global warming. Sorption on porous materials is a promising alternative to traditional carbon dioxide (CO2 ) capture technologies. Owing to their sustainable availability, economic viability, and important recyclability, natural products-derived porous carbons have emerged as favorable and competitive materials for CO2 sorption. Furthermore, the fabrication of high-quality value-added functional porous carbon-based materials using renewable precursors and waste materials is an environmentally friendly approach. This review provides crucial insights and analyses to enhance the understanding of the application of porous carbons in CO2 capture. Various methods for the synthesis of porous carbon, their structural characterization, and parameters that influence their sorption properties are discussed. The review also delves into the utilization of molecular dynamics (MD), Monte Carlo (MC), density functional theory (DFT), and machine learning techniques for simulating adsorption and validating experimental results. Lastly, the review provides future outlook and research directions for progressing the use of natural products-derived porous carbons for CO2 capture.

3.
Clin Case Rep ; 9(5): e03936, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34084478

RESUMO

We present an extremely rare report on gastric inlet obstruction due to giant abdominal aortic aneurysm. Despite the rare occurrence of this manifestation, it should be considered in the differential diagnosis of gastric inlet obstructions.

4.
Int Med Case Rep J ; 12: 373-377, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819671

RESUMO

Multiple synchronous malignancies are believed to be quite rare and their diagnosis and treatment are very challenging for physicians. Co-presence of synchronous bladder and prostate cancers in an elderly individual is not uncommon; however, the simultaneous occurrence of the third cancer - colon cancer - is extremely outlandish. In the present study, the case of an 82-year-old man with a complaint of hematuria is reported who was eventually diagnosed with three synchronous cancers: stage-3 transitional cell carcinoma of the bladder, stage-4 prostate mucinous adenocarcinoma, and stage-3 glandular adenocarcinoma of the colon. The patient underwent total colectomy and radical cystoprostatectomy followed by chemotherapy and radiotherapy. The 2-year follow-up showed promising results with no major complications and the patient's general condition was satisfactory. Although synchronous cancers are not so common, they should not be disregarded in elderly patients especially in those with multiple symptoms.

5.
Asian Spine J ; 8(6): 813-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25558325

RESUMO

STUDY DESIGN: A cross-sectional case-control study was designed to compare the sagittal alignment of lumbosacral regions in two groups of patients suffering from low back pain, one with intervertebral disc pathologies and one without. PURPOSE: To evaluate the correlation between lumbosacral sagittal alignment and disc degeneration. OVERVIEW OF LITERATURE: Changes in lumbar lordosis and pelvic parameters in degenerative disc lesions have been assessed in few studies. Overall, patients with discopathy were shown to have lower lumbar lordosis and more vertical sacral profiles. METHODS: From patients with intractable low back pain undergoing lumbosacral magnetic resonance imaging, 50 subjects with disc degeneration and 50 controls with normal scans were consecutively enrolled. A method was defined with anterior tangent-lines going through anterior bodies of L1 and S1 to measure global lumbosacral angle, incorporating both lumbar lordosis and sacral slope. Global lumbosacral angle using the proposed method and lumbar lordosis using Cobb's method were measured in both groups. RESULTS: Lumbar lordosis based on Cobb's method was lower in group with discopathy (20°-67°; mean, 40.48°±9.89°) than control group (30°-62°; mean, 44.96°±7.68°), although it was not statistically significant. The proposed global lumbosacral angle in subject group (53°-103°; mean, 76.5°±11.018°) was less than control group (52°-101°; mean, 80.18°±9.95°), with the difference being statistically significant (p=0.002). CONCLUSIONS: Patients with intervertebral disc lesions seem to have more straightened lumbosacral profiles, but it has not been proven which comes first: disc degeneration or changes in sagittal alignment. Finding an answer to this dilemma demands more comprehensive long-term prospective studies.

6.
Spine J ; 14(1): 113-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23999230

RESUMO

BACKGROUND CONTEXT: Post-laminectomy epidural fibrosis complicates revision spine surgery and is implicated in cases of "failed back syndrome." Several materials have been used to minimize epidural fibrosis with varying results. PURPOSE: The aim of this study was to examine the impact of reconstruction of laminectomy site with a type of absorbable cement (Jectos) to reduce epidural fibrosis. STUDY DESIGN: This investigation is an experimental controlled study, which is designed to evaluate the preventive effects of laminectomy site reconstruction in rat laminectomy model. METHODS: Twenty wistar rats were included in this study and divided randomly to two equal groups, namely, subject and control. In both groups, laminectomy was performed in L2 and L4 levels. Control group received no additional treatment. In the subject group, L4 levels were reconstructed by Jectos and L2 levels were non-reconstructed as internal controls. Six months after surgery the rats were sacrificed and the dural adhesion and epidural fibrosis were evaluated macroscopically and microscopically. The study was financially supported by Brain and Spinal Cord Injuries Repair Center. None of the authors have any conflict of interest. RESULTS: Non-reconstructed levels in both groups showed dense epidural fibrosis with marked dural adherence. L4 reconstructed levels in subject group showed reduced epidural fibrosis macroscopically (p=.024) and microscopically (p=.041). No foreign body reaction or ossification occurred at reconstructed sites. CONCLUSIONS: In the present study, lamina reconstruction with absorbable cement was a safe method that significantly reduced post-laminectomy epidural fibrosis and dural adhesions in rat laminectomy model.


Assuntos
Cimentos Ósseos/uso terapêutico , Espaço Epidural/cirurgia , Fibrose/prevenção & controle , Laminectomia/efeitos adversos , Aderências Teciduais/prevenção & controle , Animais , Espaço Epidural/patologia , Fibrose/etiologia , Fibrose/patologia , Vértebras Lombares , Masculino , Ratos , Ratos Wistar , Aderências Teciduais/etiologia , Aderências Teciduais/patologia
7.
J Neurol Surg A Cent Eur Neurosurg ; 75(6): 427-33, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24202963

RESUMO

OBJECTIVE: Lithium improves locomotor scores after spinal cord injury (SCI) in rats. However, the underlying mechanisms are unknown. Herein, we assess the role of nitric oxide (NO) in this action. METHODS: The first set of experiments were performed to determine a dose of lithium that effectively improves locomotor scores in rats with SCI. Therefore, rats received different doses of lithium chloride (1, 4, 10, and 20 mg/kg intraperitoneally) or saline 1 hour before SCI. In the next step, the role of NO in the effect of lithium on SCI was investigated. For this purpose, rats were co-treated with an effective dose of lithium (20 mg/kg 1 hour before SCI) and a noneffective dose of Nω-nitro-L-arginine methyl ester (L-NAME, a nonselective NO synthase inhibitor; 15 mg/kg intraperitoneally 30 minutes before SCI). SCI was induced by compressing the T9 spinal segment with an aneurysmal clip for 60 seconds in anesthetized rats. Locomotor scores were determined at 1, 3, 5, 7, 14, 21, and 28 days after SCI. Plasma lithium levels were measured 12 hours after SCI. Spinal histopathologies were examined 30 days after SCI. RESULTS: Lithium (20 mg/kg) significantly improved locomotor scores and decreased histopathologic spinal damage. l-NAME (15 mg/kg) reversed the beneficial effects of lithium. The 20-mg/kg dose of lithium resulted in a 0.68 ± 0.02 mEq/L plasma lithium concentration, which is lower than the therapeutic level in humans (0.8-1.2 mEq/L). CONCLUSION: Lithium protects against SCI through an NO-dependent mechanism.


Assuntos
Cloreto de Lítio/farmacologia , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/metabolismo , Traumatismos da Medula Espinal/prevenção & controle , Animais , Cloreto de Lítio/administração & dosagem , Cloreto de Lítio/sangue , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/sangue , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/farmacologia , Ratos , Ratos Sprague-Dawley
8.
Behav Neurol ; 27(3): 235-44, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22954588

RESUMO

PURPOSE: To evaluate patterns of activation, convergence and divergence of three functional magnetic resonance imaging (fMRI) Working Memory (WM) tasks in two different age groups. We want to understand potential impact of task and subjects' age on WM activations as well as most important areas with regard to WM functions. MATERIALS AND METHODS: Thirty-five healthy volunteers completed visual, verbal, and novel auditory WM tasks. The subjects were selected from age extremes to depict possible impact of normal aging. General Linear Model was used to report significant activations and the effect of group. One-to-one comparison of the tasks and Combined Task Analysis was also performed. RESULTS: Most of the observed differences between the tasks were seen in areas that were responsible for feature processing. Frontal regions were mainstay activation areas, regardless of the utilized stimulus. We found an age-related reduction in activity of visual (in visually-presented tasks) and auditory (in auditory task) cortices but an age-related increase in prefrontal cortex for all tasks. CONCLUSION: Regardless of the type of the task stimuli, frontal regions are the most important activation areas in WM processing. These areas are also main targets of age-related changes with regard to activation patterns. Our results also indicate that prefrontal overactivity in working memory might be a compensatory effort to mask age-related decline in sensory processing.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Lobo Frontal/fisiologia , Memória de Curto Prazo/fisiologia , Adolescente , Adulto , Idoso , Percepção Auditiva/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor/fisiologia , Percepção Visual/fisiologia
9.
Behav Neurol ; 25(4): 351-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22885811

RESUMO

PURPOSE: To evaluate patterns of activation, convergence and divergence of three functional magnetic resonance imaging (fMRI) Working Memory (WM) tasks in two different age groups. We want to understand potential impact of task and subjects' age on WM activations as well as most important areas with regard to WM functions. MATERIALS AND METHODS: Thirty-five healthy volunteers completed visual, verbal, and novel auditory WM tasks. The subjects were selected from age extremes to depict possible impact of normal aging. The General Linear Model was used to report significant activations and the effect of age group. Contrasts revealed differences in activation between tasks, and Combined Task Analysis was performed to determine common regions of activation across tasks. RESULTS: Most of the observed differences between the tasks were seen in areas that were responsible for feature processing. Frontal regions were mainstay activation areas, regardless of the utilized stimulus. We found an age-related reduction in activity of visual (in visually-presented tasks) and auditory (in auditory task) cortices but an age-related increase in prefrontal cortex for all tasks. CONCLUSION: Regardless of the type of the task stimuli, frontal regions are the most important activation areas in WM processing. These areas are also main targets of age-related changes with regard to activation patterns. Our results also indicate that prefrontal overactivity in working memory might be a compensatory effort to mask age-related decline in sensory processing.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Lobo Frontal/fisiologia , Memória de Curto Prazo/fisiologia , Estimulação Acústica , Adolescente , Adulto , Idoso , Análise de Variância , Córtex Auditivo/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Comportamento Verbal , Córtex Visual/fisiologia , Adulto Jovem
10.
Turk Neurosurg ; 21(4): 504-15, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22194108

RESUMO

AIM: The aim was to clarify the anatomical features of the superior and anterior inferior cerebellar arteries in relation to the trigeminal nerve and acoustic-facial complex and to the bony structures of the skull in a sample of male Iranian cadavers. MATERIAL AND METHODS: Bilateral dissections, calvariectomy, and brain evacuation were performed on 31 adult human fresh brains and skull bases to assess the neurovascular associations, and skull base morphometry. Equations were defined to estimate posterior fossa volume and the relationships between bony and neurovascular elements. RESULTS: Eight SCAs were duplicated from origin. There were 9 cases of SCA-trigeminal contacts, which were at the root entry zone in 7. Mean distance from the origin of AICA to the vertebrobasilar junction was 11.80 mm, while 79% of AICAs originated from the lower half of the BA. This was significantly associated with "posterior fossa funneling" and "basilar narrowing" indexes. In most cases AICA crossed the acoustic-facial complex and coursed between neural bundles (48.3%). The AICA reached or entered the internal acoustic canal in 22.6% of cases and was medial to porous in 77.4%. CONCLUSION: We documented anatomical variations of the superior and anterior inferior cerebellar arteries along with some cephalometric equations with relevant neurovascular anatomy in Iranian cadavers.


Assuntos
Artéria Basilar/anatomia & histologia , Ângulo Cerebelopontino/anatomia & histologia , Nervo Facial/anatomia & histologia , Base do Crânio/anatomia & histologia , Nervo Trigêmeo/anatomia & histologia , Nervo Vestibulococlear/anatomia & histologia , Adulto , Idoso , Antropometria/métodos , Artéria Basilar/cirurgia , Cadáver , Ângulo Cerebelopontino/cirurgia , Cerebelo/irrigação sanguínea , Fossa Craniana Média/anatomia & histologia , Fossa Craniana Média/cirurgia , Fossa Craniana Posterior/anatomia & histologia , Fossa Craniana Posterior/cirurgia , Dissecação/métodos , Nervo Facial/cirurgia , Variação Genética/fisiologia , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Modelos Neurológicos , Osso Petroso/anatomia & histologia , Osso Petroso/cirurgia , Valores de Referência , Base do Crânio/cirurgia , Nervo Trigêmeo/cirurgia , Nervo Vestibulococlear/cirurgia , Adulto Jovem
11.
Acta Neurobiol Exp (Wars) ; 70(4): 390-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21196947

RESUMO

This study aimed to examine whether celecoxib influences clonic seizure thresholds through modulation of nitric oxidergic (NO) pathway. The effect of celecoxib (1-5 mg per kg, p.o.) was investigated on clonic seizures induced by pentylenetetrazole (PTZ, 50 and 80 mg per kg, i.p.) in male Swiss mice. The interaction of celecoxib-induced effects with NO pathway was examined using a NO synthase (NOS) inhibitor, N(G)-omega-nitro-L-arginine methyl ester (L-NAME, 20 and 50 mg per kg, i.p.) and a NOS substrate, L-arginine (100 and 200 mg per kg, i.p.). The criteria for the development of seizure activity were the possibility for appearance of generalized clonus and prolongation of latency to the onset of convulsions following administration of 50 and 80 mg per kg of PTZ, respectively. Pretreatment with celecoxib (2.5 and 5 mg per kg) or L-NAME (50 mg per kg) induced anticonvulsant effect on the PTZ-induced clonic seizures. L-arginine at the dose of 200 mg per kg had proconvulsant effect. A sub-effective dose of celecoxib (1 mg per kg) induced an additive anticonvulsant effect when co-administered with L-NAME (20 mg per kg). Although L-arginine (100 mg per kg) per se did not influence PTZ-induced convulsion, it could attenuate the anticonvulsant effect of celecoxib (5 mg per kg). Our results indicate that celecoxib induces an anticonvulsant effect on clonic seizure threshold that may involve NO pathway.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia , Óxido Nítrico/metabolismo , Pentilenotetrazol/toxicidade , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Animais , Arginina/farmacologia , Celecoxib , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Masculino , Camundongos , NG-Nitroarginina Metil Éster/farmacologia , Estatísticas não Paramétricas
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