Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 176
Filter
1.
Reumatismo ; 76(2)2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38916171

ABSTRACT

OBJECTIVE: Nicotine has major side effects on human health through numerous mechanisms, one of which is the alteration of the immune system and its genetic components. Such alteration can be a predisposing factor for autoimmune diseases such as spondyloarthritis (SpA) and rheumatoid arthritis (RA). This review aims to shed light on the effects of nicotine smoking on the pathophysiology, clinical presentation, and management of SpA and RA. METHODS: This review looked into the studies, excluding case reports and series, which were cited by PubMed/MEDLINE. RESULTS: Patients with established autoimmune conditions may have a different underlying pathophysiology and disease course when exposed to nicotine through cigarette smoking. Through the involvement of several cytokines, endothelial dysfunction, and epigenetic mechanisms, the severity of SpA is more prominent in smokers. The global health status, pain, and fatigue are worse in SpA patients. The evidence on the effect of nicotine smoking on the treatment of SpA is still limited. Nicotine can contribute to RA via the disruption of cellular regulatory activity, inflammatory responses, morphological, physiological, biochemical, and enzymatic responses. As such, smokers with RA have higher disease activity and are more likely to be seropositive through the citrullination of peptides. In addition, these patients are at risk of achieving a suboptimal response to tumor necrosis factor inhibitors. CONCLUSIONS: Cigarette smoking can substantially affect the pathophysiology and clinical presentation of patients with SpA and RA. The impact of nicotine on the management of these diseases still needs to be further studied.


Subject(s)
Arthritis, Rheumatoid , Nicotine , Spondylarthritis , Humans , Arthritis, Rheumatoid/etiology , Arthritis, Rheumatoid/drug therapy , Nicotine/adverse effects , Spondylarthritis/etiology , Smoking/adverse effects
2.
Ann Intern Med ; 177(5_Supplement): S47-S56, 2024 May.
Article in English | MEDLINE | ID: mdl-38621240

ABSTRACT

This article highlights a selection of important nephrology studies published in 2023 that have relevance for nonnephrologist physicians. Four studies examined progression of chronic kidney disease or cardiovascular disease with respect to finerenone use, magnesium supplementation, iron markers, and COVID-19. Two studies examined treatments to improve specific aspects of chronic kidney disease management, including daprodustat to address anemia and patiromer to address hyperphosphatemia. One study showed that acetazolamide added to loop diuretics increased diuresis in acute decompensated heart failure across a wide range of renal function. Another study found that once-daily hydrochlorothiazide did not prevent kidney stone recurrence. Finally, an antibiotic stewardship intervention safely reduced antibiotic prescribing for suspected urinary tract infection in frail older adults.


Subject(s)
COVID-19 , Nephrology , Renal Insufficiency, Chronic , SARS-CoV-2 , Humans , COVID-19/prevention & control , Renal Insufficiency, Chronic/complications , Cardiovascular Diseases/prevention & control
3.
Med J Malaysia ; 79(Suppl 1): 128-133, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38555897

ABSTRACT

INTRODUCTION: Breastfeeding women are susceptible to musculoskeletal symptoms and hormonal changes that can affect the ocular surface. As exposure to visual display units (VDU) that is known to cause symptoms of dry eye and computer vision syndrome (CVS) is increasing worldwide, including among breastfeeding women, it is unknown whether this group of VDU users would experience CVS more than non-breastfeeding women. Therefore, this study aimed to investigate the association between breastfeeding status and symptoms of CVS and dry eye. MATERIALS AND METHODS: In this cross-sectional study, selfreported CVS and dry eye symptoms were compared between 80 breastfeeding and 72 non-breastfeeding VDU users. Two questionnaires were administered online, which were the CVS-Questionnaire (CVS-Q) and the Ocular Surface Disease Index (OSDI) questionnaire, to evaluate symptoms of CVS and dry eye, respectively. Mann-Whitney test was used to compare CVS and OSDI scores between groups, while correlations between the scores were analyzed using Spearman's test. RESULT: Results showed that OSDI scores were significantly higher in the non-breastfeeding group (U = 2263, z-score = - 2.276, p = 0.023), indicating more dry eye symptoms experienced by respondents in this group, while no significant group difference was found in terms of CVS scores (U = 2772, z-score = -0.400, p = 0.689). Additionally, no significant association was observed between breastfeeding status and severity of dry eye symptoms as well as CVS symptoms. CONCLUSION: This study reported the possible benefit of breastfeeding in reducing dry eye symptoms. The CVS symptoms found in the breastfeeding group were possibly due to VDU usage rather than caused by breastfeeding. Public education on preventive measures to reduce the occurrence of CVS symptoms and ocular dryness among VDU users is essential to improve the quality of life.


Subject(s)
Dry Eye Syndromes , Quality of Life , Humans , Female , Cross-Sectional Studies , Breast Feeding , Dry Eye Syndromes/diagnosis , Dry Eye Syndromes/epidemiology , Dry Eye Syndromes/etiology , Surveys and Questionnaires
4.
Heliyon ; 9(8): e19270, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37664699

ABSTRACT

Macrophage-arbitrated inflammation is associated with the regulation of rheumatoid arthritis (RA). Low risk and better efficiency are steered herbal drugs more credible than conventional medicines in RA management. Bhadradarvadi (BDK) concoction has been traditionally used for rheumatism in Ayurveda. However, the mechanisms at the molecular level are still elusive. This study was designed to inspect the process of immunomodulation and anti-inflammatory properties of BDK in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages for the first time. BDK concoction was prepared and evaluated with the stimulated murine macrophage-like RAW 264.7 cell lines. TNF-α, IL6, and PGE2 were quantified by ELISA. The normalization of the fold change in the expression of the target gene mRNA was done by comparing the values of the ß-actin housekeeping gene using the 2-ΔΔCt comparative cycle threshold. The expression of TNF-α, IL6, iNOS, and COX-2 in the RAW 264.7 macrophage cells was analyzed using flow cytometry. Our results showed that BDK (150-350 µl/ml) treatment significantly decreased the inflammatory cytokines (TNF-α, and IL-6) and inflammatory mediators (PGE2) in LPS-stimulated RAW 264.7 macrophage cells. The pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) expression, inflammatory enzymes (iNOS and COX-2), and NF-κBp65 were significantly downregulated at transcriptome level in LPS-stimulated RAW 264.7 macrophage cells. The flow cytometry analysis revealed that BDK treatment diminished the TNF-α, IL-6, iNOS, and COX-2 expression at the proteome level, as well as obstruction of NF-κB-p65 nuclear translocation was observed by immunofluorescence analysis in LPS-stimulated RAW 264.7 macrophage cells. Collectively, BDK can intensely augment the anti-inflammatory activities via inhibiting the NF-κB signaling pathway trigger for treating autoimmune disorders including RA.

5.
Eur Rev Med Pharmacol Sci ; 27(15): 7289-7298, 2023 08.
Article in English | MEDLINE | ID: mdl-37606137

ABSTRACT

OBJECTIVE: This study aimed to compare 12.5 mg empagliflozin effectiveness and safety vs. 50 mg sitagliptin twice daily as an add-on triple medication in Egyptians with type 2 diabetes. PATIENTS AND METHODS: Patients with hemoglobin A1c (HbA1c) between 53 and 86 mmol/mol after receiving open-label either sitagliptin 50 mg (n = 85) or empagliflozin 12.5 mg (n = 85) twice daily for 12 weeks were afterward taken into account for the administration of open-label empagliflozin 12.5 mg (n = 40) and sitagliptin 50 mg (n = 28) respectively twice daily for another 12 weeks of treatment as an added-on triple therapy. Both groups of patients kept taking metformin and empagliflozin 12.5 mg or sitagliptin 50 mg twice daily as prescribed. The HbA1c change from baseline after 12 weeks of triple-added-on therapy was the main endpoint. RESULTS: The sitagliptin group receiving empagliflozin saw a substantial drop in HbA1c, fasting and postprandial plasma glucose levels, body weight, and blood pressure compared to the starting point. As opposed to that, adding sitagliptin to the empagliflozin group non-significantly reduced HbA1c, fasting, and postprandial plasma glucose levels, and systolic blood pressure from baseline but significantly reduced body weight and diastolic blood pressure. Comparing the two groups, adding empagliflozin significantly reduced HbA1c, fasting, and postprandial plasma glucose levels (p < 0.001 for all except fasting plasma glucose level, p = 0.002). While the patient's weight and blood pressure were not significantly affected. CONCLUSIONS: Empagliflozin was superior to sitagliptin in relation to glycemic control, weight, and systolic/diastolic blood pressure reduction.


Subject(s)
Diabetes Mellitus, Type 2 , Metformin , Humans , Blood Glucose , Body Weight , Diabetes Mellitus, Type 2/drug therapy , Egypt , Glycated Hemoglobin , Metformin/therapeutic use , Sitagliptin Phosphate/therapeutic use
6.
Parasitology ; 150(10): 866-882, 2023 09.
Article in English | MEDLINE | ID: mdl-37519240

ABSTRACT

Many organisms live in fragmented populations, which has profound consequences on the dynamics of associated parasites. Metapopulation theory offers a canonical framework for predicting the effects of fragmentation on spatiotemporal host­parasite dynamics. However, empirical studies of parasites in classical metapopulations remain rare, particularly for vector-borne parasites. Here, we quantify spatiotemporal patterns and possible drivers of infection probability for several ectoparasites (fleas, Ixodes trianguliceps and Ixodes ricinus) and vector-borne microparasites (Babesia microti, Bartonella spp., Hepatozoon spp.) in a classically functioning metapopulation of water vole hosts. Results suggest that the relative importance of vector or host dynamics on microparasite infection probabilities is related to parasite life-histories. Bartonella, a microparasite with a fast life-history, was positively associated with both host and vector abundances at several spatial and temporal scales. In contrast, B. microti, a tick-borne parasite with a slow life-history, was only associated with vector dynamics. Further, we provide evidence that life-history shaped parasite dynamics, including occupancy and colonization rates, in the metapopulation. Lastly, our findings were consistent with the hypothesis that landscape connectivity was determined by distance-based dispersal of the focal hosts. We provide essential empirical evidence that contributes to the development of a comprehensive theory of metapopulation processes of vector-borne parasites.


Subject(s)
Bartonella , Flea Infestations , Ixodes , Siphonaptera , Animals
8.
Antimicrob Agents Chemother ; 66(1): e0160321, 2022 01 18.
Article in English | MEDLINE | ID: mdl-34662182

ABSTRACT

Telavancin, a lipoglycopeptide antibiotic, is traditionally dosed at 10 mg/kg based on total body weight but is associated with toxicities that limit its use. This study supports the use of a capped dosing regimen of 750 mg in obese patients, which is associated with equal efficacy and fewer adverse effects compared to traditional dosing.


Subject(s)
Aminoglycosides , Anti-Bacterial Agents , Aminoglycosides/therapeutic use , Anti-Bacterial Agents/adverse effects , Hospitals, Teaching , Humans , Lipoglycopeptides/therapeutic use
9.
New Microbes New Infect ; 43: 100926, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34367645

ABSTRACT

While many patients infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) eventually produce neutralising antibodies, the degree of susceptibility of previously infected individuals to reinfection by SARS-CoV-2 is currently unknown. To better understand the impact of the immunoglobulin (IgG) level on reinfection in recovered coronavirus disease 2019 (COVID-19) patients, anti-nucleocapsid IgG levels against SARS-CoV-2 were measured in 829 patients with a previously confirmed infection just after their recovery. Notably, 87 of these patients had no detectable IgG concentration. While there was just one case of asymptomatic reinfection 4.5 months after the initial recovery amongst patients with detectable anti-nucleocapsid IgG levels, 25 of the 87 patients negative for anti-nucleocapsid IgG were reinfected within one to three months after their first infection. Therefore, patients who recover from COVID-19 with no detectable anti-nucleocapsid IgG concentration appear to remain more susceptible to reinfection by SARS-CoV-2, with no apparent immunity. Also, although our results suggest the chance is lower, the possibility for recovered patients with positive anti-nucleocapsid IgG findings to be reinfected similarly exists.

10.
Eur Arch Paediatr Dent ; 22(4): 575-585, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33387347

ABSTRACT

OBJECTIVE: This RCT study assessed and compared the effect of a biannual application of 38% silver diamine fluoride (SDF) with alternative restorative technique (ART) on arresting caries in primary dentition. METHODS: The RCT was conducted over a period of 12 months and included 79 healthy children (237 primary teeth), aged 3-8 years, selected from the University Pediatric Dentistry outpatient clinics, with at least one primary asymptomatic tooth with active dentinal occlusal/labial lesions. Children were randomly assigned to SDF application or ART treatment. Visual and tactile examinations were used after 6 and 12 months to assess the activity of the carious lesions using the ICDAS II. RESULTS: At 6- and 12-month-evaluation periods, no statistically significant differences in lesions arrest were found between SDF and ART groups (P = 1.000). Considering the frequency of arrested caries between the test groups at 6 and 12 months, no significant differences were observed between anterior and posterior lesions, as well as between the maxillary and mandibular lesions. When comparing the working time for the two treatments, the median time for those treated with SDF was 3.3 min, compared to 14.4 min for ART and was statistically significant (P < 0.0001). CONCLUSION: Both SDF and ART are, indeed, effective for arresting caries. However, the chair-time management required for SDF is significantly shorter compared to ART. Taking into consideration the present evidence, the best decision regarding disease management and application of SDF or ART is to be made by the dentist and the patient/parent, recognizing individuals' differences and preferences.


Subject(s)
Dental Caries Susceptibility , Dental Caries , Cariostatic Agents , Child , Dental Caries/drug therapy , Dental Caries/prevention & control , Fluorides, Topical , Humans , Quaternary Ammonium Compounds , Silver Compounds
11.
PLoS One ; 15(1): e0227745, 2020.
Article in English | MEDLINE | ID: mdl-31935260

ABSTRACT

Approximate computing is an emerging design paradigm that offers trade-offs between output accuracy and computation efforts by exploiting some applications' intrinsic error resiliency. Computation of error metrics is of paramount importance in approximate circuits to measure the degree of approximation. Most of the existing techniques for evaluating error metrics apply simulations which may not be effective for evaluation of large complex designs because of an immense increase in simulation runtime and a decrease in accuracy. To address these deficiencies, we present a novel methodology that employs SAT (Boolean satisfiability) solvers for fast and accurate determination of error metrics specifically for the calculation of an average-case error and the maximum error rate in functionally approximated circuits. The proposed approach identifies the set of all errors producing assignments to gauge the quality of approximate circuits for real-life applications. Additionally, the proposed approach provides a test generation method to facilitate design choices, and acts as an important guide to debug the approximate circuits to discover and locate the errors. The effectiveness of the approach is demonstrated by evaluating the error metrics of several benchmark-approximated adders of different sizes. Experimental results on benchmark circuits show that the proposed SAT-based methodology accurately determines the maximum error rate and an average-case error within acceptable CPU execution time in one go, and further provides a log of error-generating input assignments.


Subject(s)
Algorithms , Mathematical Computing , Computer Simulation , Research Design
12.
Heliyon ; 5(11): e02675, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31840116

ABSTRACT

This work studied the role of gold nanoparticles (AuNPs) with different spherical sizes mixed with poly (3, 4-ethylene dioxythiophene): polystyrene sulfonate (PEDOT: PSS) as a hole transfer layer to enhance the efficiency (ITO/PEDOT:PSS (AuNPs)/CuPc/C60/Al) organic photovoltaic cell (OPV). AuNPs were synthesized using the thermochemical method and the results of the transmission electron microscope (TEM) images showed that the gold nanoparticles mostly dominated by spherical shapes and sizes were calculated in the range (12-23 nm). Measurements of UV-VIS spectra for AuNPs have shown that the surface plasmon resonance shifted to a higher wavelength with decreasing the particle size. Surface morphology and absorption spectra of OPV cells were studied using atomic force microscope and UV-VIS spectrometer techniques. The efficiency of the OPV cell was calculated without and with AuNPs. Efficiency was increased from 0.78% to 1.02% due to the embedded of AuNPs with (12 nm) in PEDOT/PSS. The increase in the light absorption in CuPc is due to the good transparent conducting of PEDOT:PSS and the increase in the electric field around AuNPs embedded in PEDOT:PSS and inbuilt electric field at the interfacial between CuPc and C60 is due to the surface plasmon resonance of AuNPs. The increase in these two factors increase the exciton generation in CuPc, dissociation at the interfacial layer, and charge carrier transfer which increases the collection of electrons and holes at cathode and anode.

13.
Bull Exp Biol Med ; 168(2): 229-232, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31776947

ABSTRACT

We studied the effect of a new cyanine dye containing selenium and tellurium on acetylcholinesterase activity in synaptic membrane in rat brain. The cyanine dye dose-dependently inhibits activity of this enzyme, and the concentration of half-maximal inhibition of acetylcholinesterase activity was 20.46 µM. The cyanine dye instantly inhibits the enzyme; the degree of inhibition depends on acetylthiocholine concentration: the lower is acetylthiocholine concentration, the higher is the degree of inhibition. On the Lineweaver-Burk plot, the concentration dependence curves of acetylcholinesterase with and without cyanine dye intersect in one point on the abscissa axis. In this case, the cyanine dye reduces the maximum inhibition rate (Vmax) and does not affect Michaelis constant (Km). The calculated inhibition constant Ki for the cyanine dye is 7.74 µM. Thus, the cyanine dye is a non-competitive inhibitor of acetylcholinesterase.


Subject(s)
Acetylcholinesterase/metabolism , Carbocyanines/pharmacology , Cholinesterase Inhibitors/pharmacology , Selenium/pharmacology , Synaptic Membranes/metabolism , Tellurium/pharmacology , Acetylthiocholine/metabolism , Animals , Brain/metabolism , Female , Rats , Rats, Wistar
14.
Br Poult Sci ; 60(6): 666-674, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31298555

ABSTRACT

1. Avipoxvirus (APV) infections are one of many threats inflicting economic losses within the poultry industry, particularly in tropical and subtropical countries. A proper and comprehensive study for APVs is needed to increase the knowledge concerning the diversity and evolution of the virus.2. For this purpose, 136 bird flocks of different species and breeding types were examined for APV infection between October 2016 and November 2017. One hundred and thirty samples had visible pocks on the chorioallantoic membrane (CAM) which were designated as fowl pox-like viruses via amplification of 578 bp from the P4b gene and 1800 bp from the fpv140 locus.4. A comprehensive phylogenetic analysis of fpv167 locus (P4b), fpv140 locus (fpv139 and fpv140) and fpv94 (DNA polymerase) revealed that all the analysed strains belong to fowl pox-like viruses (clade A; subclade A1 and A2). Based on the fpv140 locus full nucleotide sequence, three turkey originated strains were seen to be divergent from chicken originated sequences and branched into novel subclade A1.b.5. Trees comparison, within the term of speculation of virus-host specificity, clearly highlighted a high order specific subgrouping among subclades in the case of the fpv140 locus (including fpv139 and fpv140). Hence, the fowl poxvirus, turkey poxvirus and pigeon poxvirus strains clustered into distinct host-specific subclades A1a, A1.b and A2, respectively, which could not be seen in the FWPV-P4b and DNA polymerase phylogeny.


Subject(s)
Avipoxvirus , Bird Diseases , Poxviridae Infections , Animals , Avipoxvirus/genetics , Chickens , Egypt/epidemiology , Phylogeny , Poxviridae Infections/epidemiology , Poxviridae Infections/veterinary
15.
J Toxicol ; 2019: 6493286, 2019.
Article in English | MEDLINE | ID: mdl-31178909

ABSTRACT

Goniothalamin (GTN) is an isolated compound from several plants of the genus Goniothalamus, and its anticancer effect against several cancers was reported. However, there is no scientific data about effects of its higher doses on internal organs. Accordingly, this study aimed to evaluate the acute and subacute effects of higher doses of GTN on the hematology, biochemistry, and histology of selected internal organs of male Sprague-Dawley rats. In acute study, 35 rats were distributed in 5 groups (n=7) which were intraperitoneally (IP) injected with a single dose of either 100, 200, 300, 400, or 500 mg/kg of GTN, while extra 7 rats serve as a normal control. In subacute study, 7 rats were IP-injected with a daily dose of 42 mg/kg of GTN for 14 days, while another 7 rats serve as a normal control group. The normal controls in both studies were IP-injected simultaneously with 2 ml/kg of 10% DMSO in PBS. At the end of both tests, rats were sacrificed to collect blood for hematology and biochemistry and harvest livers, kidneys, lungs, hearts, spleens, and brains for histology. During acute and subacute exposure, no abnormal changes were observed in the hematology, biochemistry, and histology of the internal organs. However, the 300, 400, and 500 mg/kg of GTN during acute exposure were associated with morbidities and mortalities. Ultimately, GTN could be safe up to the dose of 200 mg/kg, and the dose of 42 mg/kg of GTN was tolerated well.

16.
RSC Adv ; 9(72): 42010-42019, 2019 Dec 18.
Article in English | MEDLINE | ID: mdl-35542881

ABSTRACT

A series of metal complexes were prepared from separate reactions of lanthanide nitrate salts (La(iii), Ce(iii), Sm(iii), Gd(iii) and Ho(iii)) with 4-methylbenzoylhydrazide. The structures of the complexes were confirmed by analytical studies, spectral measurements and thermal studies. Complexes were formed with different stoichiometries of 1 : 2 and 1 : 3 (M : L). The ligand chelates by the nitrogen and oxygen atoms of the amino and carbonyl groups of the hydrazide moiety in the neutral keto form. The coordination compounds were converted to metal oxide nanoparticles (MONPs) through solid state thermal decomposition as monocular source precursors. The obtained MONPs were investigated via XRD, TEM and UV-Vis spectra. As a representative, CeO2 was utilized as a nanophotocatalyst to examine the photocatalytic activity of the MONPs for methylene blue (MB) photodegradation. CeO2 showed high removal of MB dye by 90.1% after UV illumination for 220 min. The reported method provides a generalized and systematic method for the preparation of many metal oxide nanoparticles with manageable and reproducible features.

17.
Mol Biol Rep ; 46(1): 511-527, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30465133

ABSTRACT

Mycoplasma pneumoniae is a substantial respiratory pathogen that develops not only pneumonia but also other respiratory diseases, which mimic viral respiratory syndromes. Nevertheless, vaccine development for this pathogen delays behind as immunity correlated with protection is now predominantly unknown. In the present study, an immunoinformatics pipeline is utilized for epitope-based peptide vaccine design, which can trigger a critical immune response against M. pneumoniae. A total of 105 T-cell epitopes from 12 membrane associated proteins and 7 T-cell epitopes from 5 cytadherence proteins of M. pneumoniae were obtained and validated. Thus, 18 peptides with 9-mer core sequence were identified as best T-cell epitopes by considering the number of residues with > 75% in favored region. Further, the crucial screening studies predicted three peptides with good binding affinity towards HLA molecules as best T-cell and B-cell epitopes. Based on this result, visualization, and dynamic simulation for the three epitopes (WIHGLILLF, VILLFLLLF, and LLAWMLVLF) were assessed. The predicted epitopes needs to be further validated for their adept use as vaccine. Collectively, the study opens up a new horizon with extensive therapeutic application against M. pneumoniae and its associated diseases.


Subject(s)
Computational Biology/methods , Pneumonia, Mycoplasma/immunology , Pneumonia, Mycoplasma/prevention & control , Amino Acid Sequence , Epitopes/physiology , Epitopes, B-Lymphocyte/immunology , Epitopes, T-Lymphocyte/immunology , Humans , Molecular Docking Simulation/methods , Mycoplasma pneumoniae/immunology , Mycoplasma pneumoniae/pathogenicity , Protein Binding , T-Lymphocytes/immunology , Vaccines, Subunit/immunology , Viral Vaccines/immunology
18.
Microsc Res Tech ; 81(7): 755-760, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29633458

ABSTRACT

We present a method for evaluating the 3D refractive indices and 3D true stress and/or 3D true strain profiles of "isotactic polypropylene iPP" fibers during necking deformation. Observing the changes in geometrical shape during the deformation process is necessary to understand the mechanical performance of iPP fibers. 3D geometric shape profile and actual stress and strain profiles were measured for iPP fibers during the propagation of neck deformation. These measurements were performed with the aid of an in-situ opto- mechanical device to dynamically characterize different properties of fibers at different strain rates. A software image analysis program was used to calculate the 3D opto-mechanical properties of iPP fibers. The obtained results show that the used dynamic stretching device can be easily used to monitor the deformation process with high accuracy. The effective stress and strain can be determined from the filaments profile. For illustration microinterferograms are given.

19.
Skeletal Radiol ; 47(2): 173-179, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28856482

ABSTRACT

OBJECTIVE: To establish whether patterns of soft tissue injury following knee hyperextension are associated with post-traumatic 'bone bruise' distribution. MATERIALS AND METHODS: Patients with a knee MRI within one year of hyperextension injury were identified at our institution over a 7 year period. MRIs, plain radiographs and clinical details of these patients were reviewed. RESULTS: Twenty-five patients were identified (median time from injury to MRI = 24 days). The most common sites of bone bruising were the anteromedial tibial plateau (48%) and anterolateral tibial plateau (44%). There were high rates of injury to the posterior capsule (52%), ACL (40%) and PCL (40%) but lower rates of injury to the menisci (20%), medial and lateral collateral ligaments (16%) and posterolateral corner (16%). Anterior tibial plateau oedema and rupture of the posterior capsule predicted cruciate ligament injury [OR = 10.5 (p = 0.02) and 24.0 (p = 0.001) respectively]. Whilst anterolateral tibial plateau oedema strongly predicted PCL injury [OR = 26.0, p = 0.003], ACL injury was associated with a variable pattern of bone bruising. Meniscal injury was unrelated to the extent or pattern of bone bruising. 5 out of 8 patients with a 'double sulcus' on the lateral radiograph had ACL injury. The presence of a double sulcus showed significant association with anteromedial kissing contusions (OR = 7.8, p = 0.03). CONCLUSIONS: Following knee hyperextension, bone bruising patterns may be associated with cruciate ligament injury. Other structures are injured less frequently and have weaker associations with bone bruise distribution. The double sulcus sign is a radiographic marker that confers a high probability of ACL injury.


Subject(s)
Anterior Cruciate Ligament Injuries/diagnostic imaging , Contusions/diagnostic imaging , Knee Injuries/diagnostic imaging , Knee Joint/diagnostic imaging , Magnetic Resonance Imaging/methods , Adolescent , Adult , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Retrospective Studies
20.
Microsc Res Tech ; 81(3): 283-291, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29193422

ABSTRACT

Pluta microscope used to throw light on the effect of heat treatment time on the different properties of poly (ethylene terephthalate) PET fibers. PET fibers were annealed at times ranged from 5 to 30 min at different temperatures (150, 170, 190, 210°C) using two different processes (fast cooling and slow cooling processes) in air. The refractive indices, the shrinkage, orientation factor and crystallinity of PET fibers were determined for different annealing temperature during the short time treatment. The shrinkage percentage and degree of crystallinity increased with increasing the temperature and time of annealing. Microinterferograms are given for illustration.

SELECTION OF CITATIONS
SEARCH DETAIL
...