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1.
Heliyon ; 10(12): e32714, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022102

RESUMO

This research describes the methodology for synthesizing zinc oxide nanoparticles (ZnO-NPs). It demonstrates a unique, cost-effective, and non-toxic chemical technique for producing ZnO-NPs using the precipitation method with NaOH as reducing and capping agents. The formed nanoparticles have been characterized and analyzed using numerous techniques such as; Fluorescence emission spectroscopy (FL), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray Spectroscopy (EDX), ultraviolet-visible optical absorption (UV-Vis), Fourier transform infrared spectroscopy (FTIR), and Thermal gravimetric analysis (TGA). Also, the analytical technique X-ray diffraction studies has been used which showed that the ZnO-NPs had a Wurtzite hexagonal crystal structure with an average crystallite size of 34.27 nm. The form and the size of the synthesized ZnO-NPs have been seen in SEM and TEM photographs. Using J-image, particle size has been obtained at 13.33 nm, and the grain boundaries were all approximately spherical. Peaks in the FT-IR spectrum of the NPs indicate the presence of carboxylate (COO) and hydroxyl (O-H) functional groups. According to these findings, Zn interstitial defects are responsible for the 380 nm emission peak. Since EDX could not identify any impurities below the detection threshold, we may be sure that Zn and O are the principal components of the synthesized sample. ZnO-NPs cause an absorption band at 350.34 nm in the UV-Vis spectrum and a band gap of 3.24 eV. The catalytic activity of the synthesized ZnO nanoparticles (NPs) was evaluated by investigating their effectiveness in degrading crystal violet (CV) and methylene blue (MB) dyes, along with assessing the degradation rates. The results demonstrated a high degradation efficiency, with ZnO NPs achieving approximately 96.72 % degradation for CV and 97.169 % for MB dyes, underscoring their remarkable efficacy in the degradation process. As for antimicrobial activity assessment, the results revealed that the ZnO-NPs had negligible impact on Gram-negative bacteria, whereas they exhibited a discernible effect on Gram-positive bacteria. Additionally, it showed anti-cancer potential against colon (SW480), breast (MDA-231), and cervix (HELA) lines cells as seen by (MTT) assay. Hence, due to its simplified processes and cheaper chemicals, our synthesis technique may use in industrial settings for various applications.

2.
Molecules ; 29(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38257268

RESUMO

This study successfully synthesized zinc oxide nanorod needles (ZnO-NRNs) using an environmentally friendly method employing Cymbopogon Proximus extract. The resulting ZnO-NRNs exhibited exceptional physicochemical and structural properties, confirmed through various characterization techniques, including UV-Vis spectrophotometry, dynamic light scattering (DLS), transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX). The analysis revealed a hexagonal wurtzite structure with high crystallinity, a 3.6 eV band gap, and a notably blue-shifted absorption band. ZnO-NRNs showed impressive photocatalytic activity, degrading Rhodamine B dye by 97% under UV and visible sunlight, highlighting their photostability and reusability. This green synthesis process offers cost effectiveness and environmental sustainability for practical applications.

3.
Nanotechnology ; 35(8)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-37816334

RESUMO

Electrodeposited polyaniline over the carbon nanotubes fiber (CNTF) has been investigated as potential candidate to substitutes the Pt based auxiliary electrodes in unidimensional fibrous solar cells. CNTF, with excellent electrical and mechanical properties, modified with conducting polymer (polyaniline) via facile electrodeposition process which employed as cathodic materials showed efficient electrochemical reduction of triiodide ions in the fiber shaped dye-sensitized solar cells. Scanning electron microscopic analysis showed the efficacious integration of conducting polymer over the CNTF surface. The admirable electrocatalytic behavior of the fabricated electrode has investigated by electrochemical impedance spectroscopy and cyclic voltammetry. Current density and voltage (J-V) curves are used to quantify the photovoltaic performance of devices with different counter electrodes with fixed photoanode. With lower peak to peak separation, improved current density and better fill factor, exhibited the superior efficiency of modified electrode (PANI@CNTF). As compared to pristine fiber, polyaniline modification showed the outstanding performance with improved photovoltaics and electrochemical parameters measured by theJ-Vand CV curves, respectively.

4.
Plants (Basel) ; 12(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37375867

RESUMO

The growth and productivity of wheat crops depend on the availability of essential nutrients such as zinc (Zn) and potassium (K2O), which play critical roles in the plant's physiological and biochemical processes. This study aimed to investigate the synergizing effect of zinc and potassium fertilizers on uptake of both the nutrients, growth, yield, and quality of the Hashim-08 cultivar and local landrace, during the 2019-2020 growing season in Dera Ismail Khan, Pakistan. The experiment was designed using a split plot pattern in a randomized complete pattern, with main plots for the wheat cultivars and subplots for the fertilizer treatments. Results indicated that both cultivars responded positively to the fertilizer treatments, with the local landrace exhibiting maximum plant height and biological yield, and improved Hashim-08, showing increased agronomic parameters, including the number of tillers and grains and spike length. Application of Zn and K2O fertilizers significantly enhanced agronomic parameters, such as the number of grains per plant, spike length, thousand-grain weight, grain yield, harvest index, Zn uptake of grain, dry gluten content, and grain moisture content, while crude protein and grain potassium remained relatively unchanged. The soil's Zn and K content dynamics were found to vary among treatments. In conclusion, the combined application of Zn and K2O fertilizers proved beneficial in improving the growth, yield, and quality of wheat crops, with the local landrace exhibiting lower grain yield but greater Zn uptake through fertilizer application. The study's findings highlight that the local landrace showed good response to the growth and qualitative parameter when compared with the Hashim-08 cultivar. Additionally, the combined application of Zn and K showed a positive relation in terms of nutrient uptake and soil Zn and K content.

5.
Curr Probl Cardiol ; 48(7): 101661, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36822564

RESUMO

Coronary artery disease (CAD) is a serious health problem that causes a considerable number of mortality in a number of affluent nations throughout the world. The estimated death encountered in many developed countries includes including Pakistan, reached 111,367 and accounted for 9.87% of all deaths, despite the mortality rate being around 7.2 million deaths per year, or 12% of all estimated deaths accounted annually around the globe, with improved health systems. Atherosclerosis progressing causes the coronary arteries to become partially or completely blocked, which results in CAD. Additionally, smoking, diabetes mellitus, homocystinuria, hypertension, obesity, hyperlipidemia, and psychological stress are risk factors for CAD. The symptoms of CAD include angina which is described as a burning, pain or discomfort in the chest, nausea, weakness, shortness of breath, lightheadedness, and pain or discomfort in the arms or shoulders. Atherosclerosis and thrombosis are the 2 pathophysiological pathways most frequently involved in acute coronary syndrome (ACS). Asymptomatic plaque disruption, plaque bleeding, symptomatic coronary blockage, and myocardial infarction are the prognoses for CAD. In this review, we will focus on medicated therapy which is being employed for the relief of angina linked with CAD including antiplatelet medicines, nitrates, calcium antagonists, blockers, catheterization, and the frequency of recanalized infarct-related arteries in patients with acute anterior wall myocardial infarction (AWMI). Furthermore, we have also enlightened the importance of biomarkers that are helpful in the diagnosis and management of CAD.


Assuntos
Aterosclerose , Doença da Artéria Coronariana , Humanos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/terapia , Angina Pectoris , Fatores de Risco , Biomarcadores , Cateterismo
6.
J Environ Manage ; 328: 116963, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36516710

RESUMO

Since the green revolution, excessive utilization of chemical fertilizers has become prevalent due to concerns about the integrity of food production for the growing population. This indiscriminate use harms the fertility of the soil, especially in sandy soils where nutrient leaching, particularly nitrogen, results in yield losses as well as environmental and health problems. A pot experiment was carried out at Gomal University, Pakistan, in March 2022 to assess the nitrogen use efficiency, nitrogen uptake, and yield of okra. There were nine treatments with four replicates and the treatment combinations were established using a completely randomized design (CRD). Urea coated with agrotain (urease inhibitor) was applied each at 120 and 84 kg N ha-1 in 2 or 3 splits. Urea at 84 kg N ha-1 was also used in combination with Farmyard manure (FYM) and compared against the control (100% recommended urea). Obtained results showed that inhibitor-treated urea significantly increased soil concentrations of NO3-N and NH4-N over non-inhibitor-treated urea. The highest NO3-N was recorded where urea alone and urea treated with 3 L (3 L) agrotain was applied to 100%. The highest ammonical-N was recorded, where 70% urea treated with 3 L agrotain was applied. Urea, in combination with FYM, significantly increased the organic matter. Electrical conductivity in extract (ECe), and pH of the soil. The improvement in yield with inhibitor was at par with 70% and 100% urea. The highest improvement of 16% in fruit yield and 7.29% nitrogen use efficiency was obtained in the treatment receiving 120 kg N ha-1 treated with 3 L agrotain compared with non-inhibitor urea. The 2nd highest improvement of 10% in fruit yield on account of increased fruit length, stem diameter, and number of fruits, and 5.97% nitrogen use efficiency (NUE) was obtained in treatment receiving 120 kg N ha-1 in combination with FYM in comparison to control. These results suggested that the use of N inhibitor significantly increased the okra fruit yield on account of enhancing ammonical-N and increased N use efficiency.


Assuntos
Abelmoschus , Solo , Humanos , Agricultura/métodos , Esterco , Nitrogênio/análise , Ureia , Produtos Agrícolas , Fertilizantes
7.
Int J Biol Macromol ; 224: 20-31, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481331

RESUMO

Acid phosphatase (ACP) is a key enzyme in the regulation of phosphate feeding in plants. In this study, a new ACP from C. oxyacantha was isolated to homogeneity and biochemically described for the first time. Specific activity (283 nkat/mg) was found after 2573 times purification fold and (17 %) yield. Using SDS-PAGE under denaturing and nondenaturing conditions, ACP was isolated as a monomer with a molecular weight of 36 kDa. LC-MS/MS confirmed the presence of this band, suggesting that C. oxycantha ACP is a monomer. The enzyme could also hydrolyze orthophosphate monoester with an optimal pH of 5.0 and a temperature of 50 °C. Thermodynamic parameters were also determined (Ea, ΔH°, ΔG°, and ΔS°). ACP activity was further studied in the presence of cysteine, DTT, SDS, EDTA, ß-ME, Triton-X-100 H2O2, and PMSF. The enzyme had a Km of 0.167 mM and an Ea of 9 kcal/mol for p-nitrophenyl phosphate. The biochemical properties of the C. oxyacantha enzyme distinguish it from other plant acid phosphatases and give a basic understanding of ACP in C. oxyacantha. The results of this investigation also advance our knowledge about the biochemical significance of ACP in C. oxyacantha. Thermal stability over a wide pH and temperature range make it more suitable for use in harsh industrial environments. However, further structural and physiological studies are anticipated to completely comprehend its important aspects in oxyacantha species.


Assuntos
Fosfatase Ácida , Plântula , Fosfatase Ácida/química , Plântula/metabolismo , Cromatografia Líquida , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Espectrometria de Massas em Tandem , Termodinâmica , Temperatura , Fosfatos , Cinética , Peso Molecular , Especificidade por Substrato
8.
Curr Probl Cardiol ; 48(2): 101486, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336115

RESUMO

Cardiovascular disease (CVD) is a significant noncommunicable disease associated with high long-term mortality. In addition to more effective secondary therapies, the primary prevention of CVD has developed markedly in the past several years. This study aims to investigate the evidence and impact of reducing the threshold for primary CVD risk management to 10% over 10 years with "statin" therapy. To conduct research a systematic review utilizing 5 electronic database searches was completed for studies, analyzing the clinical effect of reducing the threshold of CVD risk to 10% over 10 years for primary prevention with statin therapy. The study included six (6) trials. Statin therapy was allocated to 31,018 participants. The mean age was 61 years and the mean follow-up was 4.6 years. The mean relative reduction in total cholesterol was 19% (from an average of), low-density lipoprotein cholesterol was 28.3% (from mmol/L to mmol/L) and triglycerides were 14.8% (from mmol/L to mmol/L). High-density lipoprotein cholesterol was observed to increase by a mean of 3.3% (from mmol/L to mmol/L). When examining all-cause mortality, statin therapy was associated with a 12% relative risk reduction compared with control, where overall rates were reduced from 1.4% to 1. % There is a 30% risk reduction in general major coronary events (from to %). There is a 19% risk reduction in general major cerebrovascular events with the statin group. While there is undoubtedly statistical evidence that supports the observation of the effectiveness of statin therapy for primary prevention, there is a risk that many hundreds of patients need to be treated to avoid a single adverse clinical outcome.


Assuntos
Doenças Cardiovasculares , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Pessoa de Meia-Idade , Doenças Cardiovasculares/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Triglicerídeos , LDL-Colesterol , Prevenção Primária
9.
Molecules ; 27(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35807545

RESUMO

Coming into the second year of the pandemic, the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants continue to be a serious health hazard globally. A surge in the omicron wave, despite the discovery of the vaccines, has shifted the attention of research towards the discovery and use of bioactive compounds, being potential inhibitors of the viral structural proteins. The present study aimed at the green synthesis of zinc oxide (ZnO) nanoparticles with seed extracts of Nigella sativa and Pimpinella anisum-loaded nanostructured oil carriers (NLC)-using a mixture of olive and black seed essential oils. The synthesized ZnO NLC were extensively characterized. In addition, the constituent compounds in ZnO NLC were investigated as a potential inhibitor for the SARS-CoV-2 main protease (3CLpro or Mpro) where 27 bioactive constituents, along with ZnO in the nanostructure, were subjected to molecular docking studies. The resultant high-score compounds were further validated by molecular dynamics simulation. The study optimized the compounds dithymoquinone, δ-hederin, oleuropein, and zinc oxide with high docking energy scores (ranging from -7.9 to -9.9 kcal/mol). The RMSD and RMSF data that ensued also mirrored these results for the stability of proteins and ligands. RMSD and RMSF data showed no conformational change in the protein during the MD simulation. Histograms of every simulation trajectory explained the ligand properties and ligand-protein contacts. Nevertheless, further experimental investigations and validation of the selected candidates are imperative to take forward the applicability of the nanostructure as a potent inhibitor of COVID-19 (Coronavirus Disease 2019) for clinical trials.


Assuntos
Tratamento Farmacológico da COVID-19 , Nanoestruturas , Nigella sativa , Pimpinella , Óxido de Zinco , Cisteína Endopeptidases/química , Humanos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Nigella sativa/metabolismo , Peptídeo Hidrolases/metabolismo , Extratos Vegetais/farmacologia , Inibidores de Proteases/química , SARS-CoV-2 , Sementes/metabolismo , Proteínas não Estruturais Virais/metabolismo , Óxido de Zinco/farmacologia
10.
Biosci Rep ; 40(11)2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33165619

RESUMO

BACKGROUND: Over the past few years, fabrication of nanoparticles (NPs) has been deployed widely in technologies and many concerns have emerged about the hazardous effect on human health after NPs exposure. OBJECTIVE: Green synthesis of gold NPs (AuNPs) and assessment of their activity in 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer mouse model. METHODS: Chloroauric acid (HAuCl4) was used in formation of AuNPs with the help of Curcuma longa as aqueous reducing extract and stabilizing agent at room temperature. Formed NPs were characterized with UV-Vis spectrometry, Fourier-transform infrared spectroscopy (FTIR), Zetasizer measurement, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Virgin female albino mice with DMBA-induced breast cancer were treated with formed AuNPs for 5 consecutive days and were dissected after 28 days of the beginning of treatment. RESULTS: UV-Vis spectrometry showed absorbance maximum peak at 530 nm for formed AuNPs, FTIR confirmed formation of plant extract layer around formed NPs; zetasizer measurement revealed 278.2 nm as an average size of produced NPs; SEM and TEM approved formation of monodisperse spherical AuNPs. Biochemical analysis of untreated breast cancer group revealed marked changes in liver and kidney functions manifested by raised activity levels of alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine. Whereas, the treated group with AuNPs post-breast cancer induction displayed reduction in the activities (of ALT, AST and creatinine), while the BUN activity level was raised. Histopathological examination showed heavy incidence of tumor foci in the breast and lymph nodes belonged to the untreated breast cancer group confirmed with intense response to Ki-67 antibodies. While the treated group with AuNPs post-breast cancer induction showed degenerated tumor foci in the breast and lymph nodes with weak response to Ki-67 antibodies. CONCLUSION: AuNPs were successfully synthesized using HAuCl4 and C. longa extract confirmed their ability to control DMBA-induced breast cancer in virgin female Swiss albino mice.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cloretos/farmacologia , Compostos de Ouro/farmacologia , Química Verde , Nanopartículas Metálicas , Nanomedicina , Neoplasias Experimentais/tratamento farmacológico , 9,10-Dimetil-1,2-benzantraceno , Alanina Transaminase/sangue , Animais , Antineoplásicos/química , Aspartato Aminotransferases/sangue , Nitrogênio da Ureia Sanguínea , Neoplasias da Mama/sangue , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Cloretos/química , Creatinina/sangue , Curcuma/química , Excipientes/química , Feminino , Compostos de Ouro/química , Camundongos , Neoplasias Experimentais/sangue , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/patologia , Oxirredução , Extratos Vegetais/química , Carga Tumoral/efeitos dos fármacos
11.
Pak J Pharm Sci ; 29(3): 823-36, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27166528

RESUMO

The current study was performed to study the effect of biologically synthesised gold nanoparticles (AuNPs) to control hyperglycaemic conditions in streptozotocin (STZ)-induced diabetic mice. In this study, the rats were divided into four groups: Group I normal control rats (non-diabetic, untreated); Group II diabetes-induced rats used as diabetic controls DC (diabetic, untreated). Group III diabetes-induced rats treated with AuNPs DT; Group IV normal rats treated with AuNPs NT. Diabetes was induced by administering an intraperitoneal injection of a freshly prepared solution of STZ (50mg/kg body weight (bw)). The glucose level was significantly increased in the diabetic control rats compared with the controls (P<0.001). Decreased liver function and kidney function were detected in the diabetic treated rats and normal treated rats after AuNP administration compared with the controls. The present study is the first to demonstrate that AuNPs significantly enhance antioxidant production in STZ-induced diabetic rats, a recognised model of type 1 diabetes mellitus (T1DM).


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Compostos de Ouro/farmacologia , Hipoglicemiantes/farmacologia , Nanopartículas Metálicas , Estreptozocina , Fatores Etários , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Glicemia/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/induzido quimicamente , Enzimas/sangue , Teste de Tolerância a Glucose , Masculino , Ratos , Fatores de Tempo , Ácido Úrico/sangue
12.
ACS Appl Mater Interfaces ; 7(24): 13217-31, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-25965073

RESUMO

Using the newly developed organic-inorganic colorant membrane is an attractive approach for the optical detection, selective screening and removal, and waste management recovery of highly toxic elements, such as Hg(II) ions, from water sources. In the systematic mesosponge optical sinks (MOSs), anchoring organic colorants into 3D, well-defined cage cavities and interconnected tubular pores (10 nm) in the long microscale channels of membrane scaffolds enhances the requirements and intrinsic properties of the hierarchal membrane. This scalable design is the first to allow control of the multifunctional processes of a membrane in a one-step screening procedure, such as the detection/recognition, removal, and filtration of ultratrace Hg(II) ions, even from actual water sources (i.e., tap, underground). The selective recovery, detection, and extraction processes of Hg(II) ions in a heterogeneous mixture with inorganic cations and anions as well as organic molecules and surfactants are mainly dependent on the structure of the colorant agent, the pH conditions, competitive ion-system compositions and concentrations, and Hg-to-colorant binding events. Our result shows that the solid MOS membrane arrays can be repeatedly recycled and retain their hierarchal mesosponge sink character, avoiding fouling via the precipitation of metal salts as a result of the reuse cycle. The Hg(II) ion rejection and the permeation of nonselective elements based on the membrane filtration protocol may be key considerations in water purification and separation requirements. The selective recovery process of Hg(II) ions in actual contaminated samples collected from tap and underground water sources in Saudi Arabia indicates the practical feasibility of our designed MOS membrane arrays.

13.
Asian Pac J Cancer Prev ; 13(4): 1617-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22799377

RESUMO

BACKGROUND: Gold nanoparticles have recently been investigated with respect to biocompatibility according to their interactions with cells. The purpose of this study was to examine cytotoxicity and apoptosis induction by well-characterized gold nanoparticles in human breast epithelial MCF-7 cells. METHODS: Apoptosis was assessed by TUNEL, cytotoxicity by MTT assay and caspase 3, 9, p53, Bax and Bcl expression by real-time PCR assays. RESULTS: Gold nanoparticles at up to 200 µg/mL for 24 hours exerted concentration-dependent cytotoxicity and significant upregulation of mRNA expression of p53, bax, caspase-3 and caspase-9, whereas expression of anti- apoptotic bcl-2 was down-regulated. CONCLUSION: To the best of our knowledge this is the first report showing that gold nanoparticles induce apoptosis in MCF-7 cells via p53, bax/bcl-2 and caspase pathways.


Assuntos
Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Ouro/farmacologia , Nanopartículas , Caspase 3/efeitos dos fármacos , Caspase 3/genética , Caspase 9/efeitos dos fármacos , Caspase 9/genética , Humanos , Células MCF-7 , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2/genética
14.
Comput Methods Biomech Biomed Engin ; 14(11): 987-93, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21491262

RESUMO

In the present article, we have presented the peristaltic flow of an Oldroyd 8-constant fluid in an endoscope. The governing equations for the flow problem are simplified using long wavelength and low Reynold's number approximations. The solutions of the simplified problem are calculated using (i) Homotopy analysis method and (ii) Shooting method. The comparison of both the solutions shows a very good agreement between the results. The graphical results for the velocity field and stresses are presented to show the physical behaviour of all the parameters appearing in the problem.


Assuntos
Endoscópios , Modelos Teóricos , Peristaltismo
15.
Saudi Med J ; 25(8): 1040-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15322595

RESUMO

OBJECTIVE: Despite the fact that the Kingdom of Saudi Arabia (KSA) was a pioneer in developing its bone mineral density (BMD) reference population (RP), BMD is still reported in most Saudi dual energy x-ray absorptiometry (DEXA) centers according to Lebanese RP. The aim of the current work was to assess the implication of using normal ranges other than Saudi female normal range in reporting BMD of Saudi female patients (SFP). METHODS: This study was conducted at the Security Forces Hospital, Riyadh, KSA. Three published Arabian female DEXA RPs were reviewed and statistically compared. The implication of using RPs other than Saudi female reference population (SFRP) in reporting SFP was assessed in 1653 patients who were reported according to SFRP, Lebanese female reference population (LFRP) and Kuwaiti female reference population (KFRP). All female patients' BMD data performed between June 1995 and July 2003 were included in the study. RESULTS: The 2 published SFRPs were comparable along most age decades. On the other hand, significant differences between SFRP and LFRP, and between SFRP and KFRP were noted. While the LFRP was lower than SFRP along most age decades, the KFRP was higher than the SFRP. The use of LFRP in reporting BMD values of SFP resulted in an overall false negative rate of 20%. The use of KFRP in reporting BMD values of SFP resulted in an overall false positive rate of 15%. CONCLUSION: The current use of LFRP in reporting SFP should be discontinued and instead SFRP should be used. Further national studies are needed to reassure the Saudi RP and to resolve the differences between the current 2 SFRP at the second and fifth age decades.


Assuntos
Absorciometria de Fóton/métodos , Densidade Óssea/fisiologia , Programas de Rastreamento , Osteoporose/prevenção & controle , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Estudos de Coortes , Feminino , Humanos , Kuweit , Líbano , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Arábia Saudita , Sensibilidade e Especificidade
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