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1.
Nanotechnology ; 33(41)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35793589

RESUMO

Strain control and photoluminescence (PL) enhancement of InAs surface quantum dots (SQDs), exposed to ambient conditions, have been achieved by introducing underlying buried quantum dots (BQDs). The PL wavelength has been tuned from 1270 to as long as 1780 nm, redshifted as the size of the SQDs is reduced. This is in strong contrast to standard QDs, in which blueshift is observed from smaller QDs following basic quantum mechanics. Here, smaller SQDs, both in height and base area, as observed by atomic force microscopy, were obtained with wider GaAs spacer thickness between the SQDs and BQDs. The result strongly suggests that strain and related effects dominate the electronic properties of the SQDs rather than their size, and that a change in the complex strain field occurs through the spacer. The underlying BQDs also serve as effective carrier reservoirs. A PL intensity enhancement of 17 fold was observed as the GaAs spacer thickness was reduced from 150 to 10 nm. A large portion of the photoexcited carriers is initially captured and stored in the BQDs. When sufficient carriers are transferred to fill non-radiative surface states, the excess may be transferred to the SQDs enhancing the luminescence.

2.
Sci Rep ; 11(1): 23771, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34887490

RESUMO

Serum protein levels are related to physiological and pathological status of animals and could be affected by both genetic and environmental factors. This study aimed to evaluate genetic variation of serum protein profile in sheep. Blood samples were randomly collected from 96 Lori-Bakhtiari ewes, a heavy meat-type breed. Total protein, albumin, globulin, α1, α2, ß and γ globulins and IgG levels were measured in blood serum. The samples were genotyped using the Illumina OvineSNP50 BeadChip. The studied traits adjusted for age, birth type, birth season and estimate of breeding value for body weight were considered as pseudo-phenotypes in genome-wide association analysis. In the GWAS model, the first five principal components were fitted as covariates to correct the biases due to possible population stratification. The Plink, R and GCTA software were used for genome-wide association analysis, construction of Q-Q and Manhattan plots and estimation of genetic variances, respectively. Noticeable genomic heritabilities ± SE were estimated for total and γ globulins (0.868 ± 0.262 and 0.831 ± 0.364, respectively), but other protein fractions had zero or close to zero estimates. Based on the Bonferroni adjusted p values, four QTLs located on 181.7 Mbp of OAR3, 107.7 Mbp of OAR4, 86.3 Mbp of OAR7 and 83.0 Mbp of OAR8 were significantly associated with α1, ß, ß and γ globulins, respectively. The results showed that the PKP2, IGF2R, SLC22A1 and SLC22A2 genes could be considered as candidate genes for blood serum proteins. The present study showed significant genetic variations of some blood protein fractions.


Assuntos
Proteínas Sanguíneas/genética , Estudo de Associação Genômica Ampla , Genômica , Padrões de Herança , Ovinos/sangue , Ovinos/genética , Alelos , Animais , Genética Populacional , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Genótipo , Irã (Geográfico) , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
3.
J Mech Behav Biomed Mater ; 115: 104283, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33412404

RESUMO

The primary purpose of this paper is to outline a methodology for evaluating the likelihood of cortical bone fracture in the proximal femur in the event of a sideways fall. The approach includes conducting finite element (FE) analysis in which the cortical bone is treated as an anisotropic material, and the admissibility of the stress field is validated both in tension and compression regime. In assessing the onset of fracture, two methodologies are used, namely the Critical Plane approach and the Microstructure Tensor approach. The former is employed in the tension regime, while the latter governs the conditions at failure in compression. The propagation of localized damage is modeled using a constitutive law with embedded discontinuity (CLED). In this approach, the localized deformation is described by a homogenization procedure in which the average properties of cortical tissue intercepted by a macrocrack are established. The key material properties governing the conditions at failure are specified from a series of independent material tests conducted on cortical bone samples tested at different orientations relative to the loading direction. The numerical analysis deals with simulations of experiments involving the sideways fall, and the results are compared with the experimental data. This includes both the evolution of fracture pattern and the local load-displacement characteristics. The proposed approach is numerically efficient, and the results do not display a pathological mesh-dependency. Also, in contrast to the XFEM approach, the analysis does not require any extra degrees of freedom.


Assuntos
Fraturas do Quadril , Acidentes por Quedas , Osso Cortical , Fêmur , Análise de Elementos Finitos , Humanos
4.
Int J Organ Transplant Med ; 12(3): 12-20, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35509721

RESUMO

Background: Five epigenetic regulator mutations are considered in myeloproliferative neoplasms (MPN) that have prognostic and therapeutic values. Objective: We aimed to evaluate these mutations in MPNs among the Iranian population. Methods: We selected 5 mutations in 4 epigenetic regulatory genes [TET2, DNMT3A, IDH1 (rs147001633&rs121913499), and JAK2)] and evaluated 130 patients with MPNs including 78 Philadelphia chromosome negative (49 ETs, 20 PVs, and 9 PMFs) and 52 Philadelphia chromosome-positive patients as well as 51 healthy controls. Results: Eight patients (6.5%) carried the DNMT3A mutation, 35 (27%) were positive for TET2 mutation and 64 (49.3%) had the JAK2V617F mutation. In the healthy controls, 16 (31.4%) cases had the TET2 mutation (15 Heterozygote + 1 Homozygote) and one had heterozygote JAK2 mutation. There was no statistically significant difference between patient groups for any of these mutations, except for JAK2. The JAK2 mutation rate was 18 (90%), 25 (51%), 7 (77.8%), 14 (26.9%) in polycythemia vera, essential thrombocythemia, primary myelofibrosis, and chronic myelocytic leukemia, respectively. Patients aged 60 and older were more likely to carry the TET2 mutation (23% vs. 39% in younger and older than 60 years old individuals, p=0.025). IDH1 was not detected at all and PV had the highest TET2 mutation 7(35%). Two PMF patients had a history of bone marrow transplantation that were negative for IDH1and DNMT3A and one was positive for TET2 mutation. Conclusion: In the normal Iranian population, the heterozygote form of TET2 mutation is significant, especially in the elderly. No association was found between JAK2 and TET2 mutations. Both of them are more prevalent in the age group of 60 years and older. DNMT3A mutation has a low prevalence and occurs in both positive and negative MPNs.

5.
Osteoporos Int ; 31(9): 1671-1682, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32361950

RESUMO

The relationship between heavy metal exposure and risk of osteopenia or osteoporosis has biological plausibility, yet it remains inconclusive; therefore, we conducted a systematic review and meta-analysis to evaluate the associations between exposure to heavy metals (i.e., cadmium, lead, and mercury) and the risk of osteopenia or osteoporosis. Databases of MEDLINE, Embase, Scopus, and Web of Science were searched through November 2019, to identify studies that evaluated the relationship between exposure to cadmium, lead, and mercury and risk of osteopenia or osteoporosis in adults. Fourteen eligible studies were included. Effect sizes expressed as pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated using weighted random-effect models. Exposure to cadmium (OR = 1.35; 95% CI: 1.17 to 1.56; P ≤ 0.001) and lead (OR = 1.15; 95% CI: 1.00 to 1.32; P = 0.05) was associated with an increased risk of osteopenia or osteoporosis, unlike mercury. Subgroup analyses showed cadmium exposure increased the risk of osteopenia or osteoporosis in older (> 65 yrs.; OR = 1.43; 95%CI: 1.08 to 1.88, P = 0.01) compared with younger (18-65 yrs.; OR = 1.24; 95% CI: 1.02 to 1.52, P = 0.03) adults. Also, lead exposure increased the risk in men (OR = 1.55; 95% CI: 1.15 to 2.09, P = 0.007) unlike in women. By contrast to urinary levels, blood (OR = 1.26; 95% CI: 1.08 to 1.47, P = 0.003) and dietary (OR = 1.46; 95% CI: 1.28 to 1.67, P < 0.001) levels of cadmium were associated with an increased risk of osteopenia or osteoporosis. Exposure to cadmium and lead may be associated with an increased risk of osteopenia or osteoporosis, although high heterogeneity was detected.


Assuntos
Doenças Ósseas Metabólicas , Mercúrio , Metais Pesados , Osteoporose , Adulto , Idoso , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/epidemiologia , Cádmio/toxicidade , Feminino , Humanos , Masculino , Mercúrio/toxicidade , Metais Pesados/toxicidade , Osteoporose/induzido quimicamente , Osteoporose/epidemiologia
6.
Biomech Model Mechanobiol ; 19(5): 1953-1963, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32157456

RESUMO

This paper is focused on specification of conditions at failure in bovine cortical bone. Both experimental and analytical studies are conducted. The experimental part includes a series of novel direct shear tests which examine the sensitivity of shear strength to the applied normal stress for different orientations of the sample microstructure. These experiments are supplemented by standard axial compression and tension tests in order to define and quantify a general form of failure criterion. The analytical part examines two different methodologies, viz. critical plane approach and microstructure tensor approach, for defining the anisotropic strength criterion. A procedure for identification of material parameters is outlined which is based on the results of the performed material tests.


Assuntos
Osso Cortical/fisiologia , Animais , Anisotropia , Bovinos , Osso Cortical/diagnóstico por imagem , Análise Numérica Assistida por Computador , Resistência ao Cisalhamento , Estresse Mecânico , Resistência à Tração , Microtomografia por Raio-X
7.
Br Poult Sci ; 61(3): 251-257, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32008362

RESUMO

1. Theoretically, haplotype blocks might be a more suitable alternative to SNP genotypes as they are usually better at capturing multi-allelic QTL effects, compared to individual SNP genotypes in genome-wide association studies. The objectives of this study were to identify genomic regions related to egg weight traits by Bayesian methods (BayesA, BayesB, and BayesN) that fit fixed-length haplotypes using GenSel software. 2. Genotypes at 294,705 SNPs, that were common on a 600K Affymetrix chip, were phased for an egg-laying hen population of 1,063 birds. Recorded traits included first egg weight (FEW) and average egg weight at 28, 36, 56, 66, 72 and 80 weeks of age. 2. Fitting 1Mb haplotypes from BayesB resulted in the highest proportion of genetic variance explained for the egg weight traits. Based on the trait, the genetic variance explained by each marker ranged from 27% to 76%. 3. Different haplotype windows associated with egg weight traits only explained a small percentage of the genetic variance. 4. The top one 1-Mb window on GGA1 explained approximately 4.05% of total genetic variance for the FEW. Candidate genes, including PRKAR2B, HMGA2, LEMD3, GRIP1, EHBP1, MAP3K7, and MYH were identified for egg weight traits. 5. Several genomic regions, potentially associated with egg weight traits, were identified, some of which overlapped with known genes and previously reported QTL regions for egg production traits.


Assuntos
Galinhas/genética , Estudo de Associação Genômica Ampla/veterinária , Animais , Teorema de Bayes , Feminino , Genômica , Haplótipos , Fenótipo , Polimorfismo de Nucleotídeo Único
8.
J Neurosurg Sci ; 63(3): 280-285, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-25566746

RESUMO

AIM: To translate and validate the Child and Family Follow--up Survey (CFFS) in Iran. METHODS: 49 cases with Acquired Brain Injury (ABI), and 30 healthy children were included and the CFFS was completed. The Pediatric Quality of Life Inventory (PedsQL) also was completed. The internal consistency, test-retest reliability, known groups comparison and criterion validity were assessed. RESULTS: The mean age of participants was 10.9 years. Cronbach's alpha coefficients were Child and Adolescent Scale of Participation (CASP) (0.91), Child and Adolescent Factors Inventory (CAFI) (0.90) and Child and Adolescent Scale of Environment (CASE) (0.89). Reliability, validity and correlation of CASP and CAFI showed satisfactory results. Significant correlations among the three CFFS subscale scores were observed. These scores were also significantly correlated with the total scores of the PedsQL. CONCLUSION: The findings suggest that CFFS is a valid measure to monitor long--term outcomes of children and young adolescents with ABI.

9.
Scand J Immunol ; 87(5): e12663, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29574865

RESUMO

Common variable immunodeficiency (CVID) is the most prevalent symptomatic type of human primary immunodeficiency diseases (PID). Clinically, CVID is characterized by increased susceptibility to infections and a wide variety of autoimmune and rheumatologic disorders. All patients with CVID registered in Iranian PID Registry (IPIDR) were enrolled in this retrospective cohort study. We investigated the frequency of rheumatologic diseases and its association with immunological and clinical phenotypes in patients with CVID. A total of 227 patients with CVID were enrolled in this study. The prevalence of rheumatologic disorders was 10.1% with a higher frequency in women than men. Most common rheumatologic manifestations were juvenile idiopathic arthritis (JIA) and adult rheumatoid arthritis (RA) followed by juvenile spondyloarthritis (JSpA) and undifferentiated inflammatory arthritis (UIA). Septic arthritis in patients with CVID with a history of RA and JIA was higher than patients without rheumatologic complication. Patients with CVID with a history of autoimmunity (both rheumatologic and non-rheumatologic autoimmunity) had lower regulatory T cells counts in comparison with patients without autoimmune disorders. There was an association between defect in specific antibody responses and negative serologic test results in patients with rheumatologic manifestations. JIA, RA, JSpA and UIA are the most frequent rheumatologic disorders in patients with CVID. Due to antibody deficiency, serologic tests may be negative in these patients. Therefore, these conditions pose significant diagnostic and therapeutic challenges for immunologists and rheumatologists in charge of the care for these patients.


Assuntos
Artrite Juvenil/epidemiologia , Artrite Reumatoide/epidemiologia , Artrite/epidemiologia , Imunodeficiência de Variável Comum/imunologia , Imunodeficiência de Variável Comum/patologia , Espondilite Anquilosante/epidemiologia , Adolescente , Adulto , Anticorpos/sangue , Artrite/complicações , Artrite Juvenil/complicações , Artrite Reumatoide/complicações , Autoimunidade/imunologia , Imunodeficiência de Variável Comum/complicações , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Contagem de Linfócitos , Masculino , Estudos Retrospectivos , Espondilite Anquilosante/complicações , Adulto Jovem
12.
Eur J Clin Nutr ; 2017 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-28832573

RESUMO

BACKGROUND/OBJECTIVES: Pemphigus vulgaris (PV), as an autoimmune disease including mucosa and the skin, is associated with several complications and comorbidities. The present study planned to determine the effect of L-carnitine (LC) supplementation on biomarkers of oxidative stress (OS), antioxidant capacity and lipid profile in PV patients.Subjects/MethodsFifty two control and patients with PV, participated in the current randomized, double-blind, placebo-controlled clinical trial. The patients were allocated randomly to receive 2 g per day LC tartrate subdivided into two equal doses of 1 g before breakfast and dinner (n=26) or placebo (n=26) for 8 weeks. Anthropometric, lipid profile and OS values were determined at baseline and end of intervention period. RESULTS: LC intake significantly reduced serum levels of triglycerides, total-, LDL- cholesterol and oxidative stress index (OSI; P<0.05). In addition, supplementation with LC resulted to a meaningful increase in levels of total antioxidant capacity (TAC) (P=0.05) and serum carnitine (P<0.001). LC intake revealed non-significant change in serum total oxidant capacity (P=0.15) and HDL- cholesterol (P=0.06) in comparison to the placebo. CONCLUSIONS: LC consumption may have favorable results on TAC, OSI and lipid profiles in patients with PV. The results were in line with the idea that LC supplementation can be associated with positive effects on metabolic status and OS of patients with PV.European Journal of Clinical Nutrition advance online publication, 23 August 2017; doi:10.1038/ejcn.2017.131.

13.
Reprod Domest Anim ; 52(2): 298-304, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28109029

RESUMO

The objective of this study was to investigate the effects of L-cysteine-coated iron oxide nanoparticles on reproductive performance in breeder quails. The five treatment diets consisted of (i) negative control diet not supplemented with iron, (ii) positive control diet supplemented with 60 mg/kg of Fe3 O4 and (iii) experimental diets supplemented with 0.6, 6 and 60 mg/kg of L-cysteine-coated iron oxide nanoparticles. A total of 100 seven-day-old quail chicks were weighed and randomly placed to five groups of five replicate cages. Four quails (one male and three females) were raised in each cage (50 × 15 × 17 cm). Egg production, feed consumption and egg weight were recorded daily and calculated on a hen per day basis. Egg components, fertility, hatchability and day-old chicks hatched from their eggs were measured at the end of the experiment. The percentage of egg production and egg mass of the 6 mg/kg Fe3 O4 -Cys NPs group were significantly higher than those of the control groups. Throughout the experimental period, the highest weekly egg weight was recorded for the 60 mg/kg Fe3 O4 -Cys NPs group. Fertility was improved by diet supplemented with iron, both FeSO4 and Fe3 O4 -Cys NPs. The breeder fed Fe3 O4 -Cys NPs had the highest day-old chicks weight. The results of this study showed that Fe3 O4 nanoparticles that were coated by L-cysteine could improve availability and utilization of iron in diet. Finally, it was proposed that Fe3 O4 -Cys NPs could be used as feed additives in quails.


Assuntos
Ração Animal/análise , Cisteína/farmacologia , Dieta/veterinária , Compostos Férricos/química , Codorniz/fisiologia , Reprodução/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cisteína/administração & dosagem , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Compostos Férricos/administração & dosagem , Nanopartículas/administração & dosagem , Nanopartículas/química , Reprodução/fisiologia
14.
Scand J Immunol ; 85(1): 13-29, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27862144

RESUMO

Primary immunodeficiency diseases (PIDs) consist of a genetically heterogeneous group of immune disorders that affect distinct elements of the immune system. PID patients are more prone to infections and non-infectious complications, particularly autoimmunity. The concomitance of immunodeficiency and autoimmunity appears to be paradoxical and leads to difficulty in the management of autoimmune complications in PID patients. Therefore, management of autoimmunity in patients with PID requires special considerations because dysregulations and dysfunctions of the immune system along with persistent inflammation impair the process of diagnosis and treatment.


Assuntos
Autoimunidade , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/terapia , Imunoterapia/métodos , Animais , Autoantígenos/imunologia , Autoimunidade/genética , Diagnóstico Diferencial , Humanos , Tolerância Imunológica , Síndromes de Imunodeficiência/diagnóstico , Mutação/genética
15.
Reprod Domest Anim ; 52(1): 44-48, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27641731

RESUMO

The effects of three climates (hot and dry, mild and humid and Alpine) and three flock densities (<100, 100-300 and >300 m2 ) on ostrich reproductive and productive traits were studied. Data were compared with the benchmark target sets by the World Ostrich Association (Ostrich benchmark Performance Targets. Version 2, May, 2008) for reproductive qualifications of ostrich. No significant difference was observed on egg production, weight, fertility, hatchability and day-old chicks weight among the three climate conditions; however, the Alpine climate had a lower performance trend. Mild and humid climates had a significant effect of age at sexual maturity for both males and females as well as on the duration of egg production season. Stocking density did not show significant difference on egg production, hatchability, age of male and female at sexual maturity and on duration of egg production season, while an area >300 m2 showed a reduction in egg weight and day-old chick weight. Further, an area <100 m2 led to a weaker ostrich fertility rate. Results showed that the ostrich would have a better performance under hot and dry and mild and humid climates as compared to Alpine climate with a stocking density of 100-300 m2 area per breeder bird. Thus, climatic intervention strategies at Alpine regions may be carried out for maintaining optimal reproductive qualification of ostrich so as to improve the productivity in this sector.


Assuntos
Criação de Animais Domésticos/métodos , Clima , Fertilidade/fisiologia , Oviposição/fisiologia , Reprodução/fisiologia , Struthioniformes , Animais , Cruzamento , Feminino , Masculino , Densidade Demográfica , Estações do Ano
16.
Cancer Gene Ther ; 23(11): 396-399, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27767089

RESUMO

Gastric cancer is among the leading causes of cancer-related death, and the symptoms are commonly characterized in advanced stages. Histone acetylation is among the most important epigenetic alterations occurring during cancer development. In addition, reduced E-cadherin expression is a major contributor in the process of tumor cell invasion and metastasis. Oxamflatin is a histone deacetylase inhibitor that has been suggested as a promising anti-tumor agent; yet its effect on the viability and invasion of gastric tumor cells is unclear. We aimed to assess the impact of oxamflatin on the viability of gastric tumor cells and expression of E-cadherin as a marker of tumor invasion susceptibility. In this study, MKN-45 cells were treated with 1, 2.5 and 5 mM oxamflatin and followed by MTT assay after 24-48 h of incubation. To determine E-cadherin expression in treated cells, total RNA was extracted and reverse transcribed to complementary DNA, followed by quantitative real-time PCR. MTT results showed that the viability of MKN-45 cells declines with increasing concentrations of oxamflatin. The results of quantitative real-time PCR showed increased expression of E-cadherin following treatment with oxamflatin at the concentration of 2.5 mM compared with 1 mM. The present results showed that oxamflatin can induce E-cadherin expression and also reduce cell viability in the MKN-45 cell line. On the basis of these findings, oxamflatin can be further considered for the prevention of tumor metastasis.


Assuntos
Antineoplásicos/farmacologia , Caderinas/genética , Ácidos Hidroxâmicos/farmacologia , Antígenos CD , Caderinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Gástricas
17.
Pol J Vet Sci ; 19(3): 573-580, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27760041

RESUMO

From economical point of view, Dicrocoelium Dendriticum (D. dendriticum) causes a lot of damages to the livestock industry annually. So, the rapid diagnosis of infection is very important. The diagnosis is based on egg per count of feces (EPG) test because detection according to clinical symptoms is difficult. Since EPG is not accurate and sensitive, the serological methods become important for the diagnosis of this parasite as they are more accurate in comparison to EPG test and they are able to diagnose infection in a short time. In this study, somatic and Excretory-secretory antigens (EsAg) were isolated. The ELISA test was set up according to positive and negative sera and the results which were obtained compared to those obtained by the EPG test. The prevalence of infection in 550 samples by ELISA and EPG methods were 56% and 7% respectively, which shows the significant difference between these methods in examining the rate of infection. Based on the results, the specificity and sensitivity in ELISA test were 95% and 94%, respectively. The results showed that the ELISA is a more reliable test in comparison to EPG test for the rapid diagnosis of D. dendriticum infection.


Assuntos
Dicrocelíase/veterinária , Dicrocoelium/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Contagem de Ovos de Parasitas/veterinária , Doenças dos Ovinos/parasitologia , Animais , Antígenos de Helmintos , Dicrocelíase/diagnóstico , Fezes/parasitologia , Feminino , Proteínas de Helminto , Masculino , Ovinos , Doenças dos Ovinos/diagnóstico
18.
Ann Med Health Sci Res ; 6(5): 274-279, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28503343

RESUMO

BACKGROUND: Crystalline silica is a commonly used mineral in various industries and construction activities, and it is so important introducing potential biomarkers to identify early indicators of biological effects in its high-risk occupational exposures. AIM: The present study was aimed to assess the blood and urinary neopterin as an early biomarker of exposure in the workers of an insulator manufacturing plant who are exposed to crystalline silica. SUBJECTS AND METHODS: This analytical descriptive study was done among two groups of exposed workers (n = 55) and unexposed office workers (n = 38) of an insulator manufacturing plant. Statistical software R was used to determine sample size and select the participants by random sampling among nonsmoker workers. Sampling of airborne silica in breathing zone of participants was done based on the National Institute for Occupational Safety and Health method 7601. The urinary and blood samples were collected and prepared for analysis by high-performance liquid chromatography to determine the level of urinary and serum neopterin. All of the statistical analyses were carried out using SPSS 22. RESULTS: The airborne silica concentration was significantly different between two exposed and unexposed groups (P < 0.001, 0.27 [0.11] vs. 0.0028 [0.0006] mg/m3, respectively). The urinary neopterin in exposed group is significantly higher than the unexposed one (P < 0.001, 97.67 [30.24] vs. 55.52 [2.18] µmol/mol creatinine, respectively). Neopterin level of serum in exposed group is higher than the unexposed group, and there is a significant difference between them (P < 0.001, 6.90 [2.70] vs. 2.20 [1.20] nmol/l, respectively). The positive significant correlations were found between silica exposure concentration with urinary and serum neopterin (P < 0.001, r = 0.36 and 0.59, respectively). CONCLUSIONS: Considering the sensitively and easily measurement of neopterin in biological fluid and also the statistically significant positive relationships which were found between the airborne silica concentration and neopterin levels in the present study, the serum and urinary neopterin levels can be considered the potential biomarkers of silica exposure for doing further comprehensive studies in this area.

19.
Biochim Biophys Acta ; 1853(10 Pt A): 2526-38, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26025676

RESUMO

Migrating cells sense variations of stiffness in connective tissue matrices but how cells detect and respond to stiffness orientation is not defined. We examined cell extension formation on collagen with underlying support (vertical stiffness gradient) or on collagen laterally supported by nylon (lateral stiffness gradient). At 6 h after plating, cells plated on laterally-supported collagen exhibited >2-fold more abundant and ~2-fold longer cell extensions than cells plated on collagen with underlying support. We examined whether p21-activated kinase 1 (PAK1) influences extension formation that is dependent on the orientation of support. At 6 h after plating on collagen with underlying support, wild-type cell extensions were 40% shorter than PAK1 knockdown cells. In contrast, on laterally-supported collagen, wild-type cell extensions were 2-fold longer than PAK1 knockdown cells. In cells plated on laterally-supported collagen, there were ~2-fold reductions of collagen fiber alignment and compaction in PAK1 knockdown cells compared with wild-type cells. PAK1 knockdown did not affect collagen fiber alignment or compaction by cells plated on collagen with underlying support. Wild-type cells with lateral support of collagen exhibited 3-fold increases of phospho-myosin staining at 6h, which was 2-fold lower in PAK1 knockdown cells. In contrast, cells on collagen with underlying support showed no increase of phospho-myosin staining at any times. PAK1 knockdown did not affect α2 or ß1 integrin expression or function. We conclude that PAK1 is involved in the ability of cells to sense the orientation of stiffness in collagen substrates and generate contractile forces that affect cell extension formation.


Assuntos
Extensões da Superfície Celular/metabolismo , Colágeno/química , Integrina alfa2/metabolismo , Integrina beta1/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Extensões da Superfície Celular/genética , Técnicas de Silenciamento de Genes , Integrina alfa2/genética , Integrina beta1/genética , Camundongos , Miosinas/genética , Miosinas/metabolismo , Células NIH 3T3 , Quinases Ativadas por p21/genética
20.
J Sports Med Phys Fitness ; 55(9): 969-77, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25394475

RESUMO

AIM: Posture and plantar pressure distribution can influence several factors, including both foot type and heritability. Therefore, the purpose was to assess the influence of foot type and heritability and their effects on foot characteristics. Static and dynamic balance and plantar pressure distribution was assessed, and the participants were pairs of female twins. METHODS: Sixteen monozygotic and fourteen dizygotic pairs with no history of injuries were included in this causal-comparative study, divided into three foot types by navicular drop test: pes planus, pes rectus and pes cavus. Static balance was measured using the stork test and dynamic balance using the SEBT test. Plantar pressure distributions were measured by the emed platform. Two-way ANOVA, F test, heritability estimate, intraclass correlation coefficient and Fisher Z test were used for statistical analysis. RESULTS: No significant differences were found between foot types or zygosities in static and dynamic balance and peak pressure (P>0.05). Within-pair variances were significantly different in dynamic balance in PL and L directions (P<0.05). Heritability was 0.43, 0.52, 0.62, 0.65 and 0.39 in static balance and dynamic balance variables in P, PL, L and mean of eight directions, respectively. Genetic factors revealed no influence on peak pressure. Within-pair correlations were significantly different in dynamic balance results in PL and L directions (P<0.05). CONCLUSION: Foot type and zygosities had no influence on balance or peak pressure. Genetic factors moderately influenced postural balance, but not peak pressure. The current study is an asset to identify and manage influential factors in these variables for female twins.


Assuntos
Pé/fisiologia , Postura/fisiologia , Pressão , Adulto , Feminino , Humanos
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