The effect of Fe-Zn mole ratio (2:1) bimetallic nanoparticles supported by hydroxyethyl cellulose/graphene oxide for high-efficiency removal of doxycycline.

In this research, Hydroxyethyl cellulose - graphene oxide HEC-GO and HEC-GO/Fe-Zn mole ratio (2:1) nanocomposite as adsorbents were fabricated by crosslinking ethylene glycol dimethacrylate (EGDMA) to study the thermodynamic, kinetic and isotherm of doxycycline antibiotic adsorption. The morphology and structure of the adsorbents were analyzed by Fourier transform infrared spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (FE-SEM- EDX), and Transmission electron microscopy (TEM). The adsorption behavior of doxycycline (DOX) was studied with different parameters including doxycycline concentration, pH, the dose of adsorbent (HEC-GO and HEC-GO/Fe-Zn, mole ratio (2:1)), contact time, and temperature. The optimal conditions for the removal of DOX are pH = 3.0, contact time 100 min, and 20 min for HEC-GO and HEC-GO/Fe-Zn mole ratio (2:1). The removal percentage for HEC-GO and HEC-GO/Fe-Zn mole ratio (2:1) was 97% and 95.5%, respectively. Equilibrium adsorption isotherms such as the Langmuir, Freundlich, and Temkin models were analyzed according to the experimental data. Also, four adsorption kinetics were investigated for removing DOX. The Langmuir isotherm and pseudo-second-order kinetic models provided the best fit for experimental data for HEC-GO and HEC-GO/Fe-Zn mole ratio (2:1). Thermodynamic data showed that negative values of Gibbs free energy (ΔG°) and the negative value of enthalpy (ΔH°) of the adsorption process for adsorbents. It means that DOX removal was a spontaneous and exothermic reaction.

Molecular Characteristics of Staphylococcus aureus Strains Isolated from Nasal Cavity and Wound Infections Among Diabetic Patients.

Staphylococcus aureus is the most common pathogen contributing to diabetic foot infections (DFI). Nasal transmission of S. aureus potentially increases the risk of endogenous infection. The aim of this study was to determine the genetic diversity and antibiotic resistance profile of S. aureus isolates in nasal and wound samples from diabetic patients. A cross-sectional study was conducted from July 2018 to September 2019. S. aureus was isolated from the anterior nares and wounds of diabetic patients. All S. aureus isolates were characterized by detection of resistance and virulence genes (mecA, ermA, ermC, hla, hlb, hlg, sea, lukDE, pvl), staphylococcal cassette chromosome mec (SCCmec)-typing and staphylococcal protein A (spa)-typing. A total of 34 S. aureus were isolated from the wounds of 115 diabetic patients with DFI. Twenty-four S. aureus isolates were collected from the anterior nares of patients, and thirteen patients had concurrent S. aureus in nasal and wound specimens. The prevalence of methicillin-resistant S. aureus (MRSA) in nasal specimens was noticeable (41.7%), and the most common spa-type in nasal and wound specimens was t14870. Nearly half of the patients with concurrent S. aureus in wound and nasal specimens had similar isolates from both sites. Our data suggest that detection and screening of S. aureus colonization in the nasal cavity may prevent subsequent endogenous infections, particularly with MRSA strains.

Ovarian volume, not follicle count, is independently associated with androgens in patients with polycystic ovary syndrome.

BACKGROUND: Polycystic ovary syndrome (PCOS) is diagnosed based on chronic anovulation, androgen excess (clinical and/or biochemical), and polycystic ovaries in ultrasound. The aim of the present study was to evaluate which parameters in the transvaginal ultrasound (TVUS) of ovaries could be better associated with concurrent hormonal imbalance in the women with PCOS. METHODS: Using a cross-sectional design, this study focused on 61 subjects (18-40 years) with PCOS. Patients were recruited at three academic hospitals during the 2017-2019 period. PCOS was defined according to the Rotterdam criteria. The association of ovarian morphology with hormonal and metabolic feature was investigated using linear regression models, adjusted for a set of possible confounding variables including age, mensuration status and body mass index (BMI). RESULTS: The mean volume of both ovaries was positively associated with the total testosterone level (ß = 0.025, P value < 0.001), free androgen index (ß = 0.041, P value < 0.001) and luteinizing hormone/follicle stimulating hormone (LH/FSH) ratio (ß = 0.032, P value = 0.004), even after adjustments made for age, mensuration status and BMI (fully-adjusted model). In contrast, in the fully-adjusted model, antral follicle count (AFC), follicle number per ovary (FNPO), ovarian area, stromal area, and ratio of stromal area to ovarian area (S/A) were not associated with androgen levels and LH/FSH ratio. In addition, after full adjustments, ovarian volume, AFC, FNPO, ovarian area, stromal area and S/A were not associated with insulin resistance, which was estimated by the homeostasis model assessment of insulin resistance (HOMA-IR). CONCLUSION: Increased ovarian volume is, thus, highly predictive of hyperandrogenemia and high LH/FSH ratio in PCOS patients.

Developmental trajectories of body mass index since childhood and health-related quality of life in young adulthood: Tehran Lipid and Glucose Study.

PURPOSE: The association between long-term BMI changes since childhood and health-related quality of life (HRQoL) in adulthood is still unclear. This study aimed to examine the association between identified BMI trajectories and HRQoL. METHODS: A population-based cohort of 1938 eligible children (3-18 years) and their parents have been repeatedly followed up for 18 years. Offspring BMI trajectories were identified using group-based trajectory models. HRQoL was evaluated in offspring aged 21-36 years using SF-12V2. Using quantile regression analysis, the associations of the identified BMI trajectories and HRQoL in young adulthood were examined. RESULTS: In males, persistent increasing overweight/obese group was negatively associated with 30th, 40th, 50th, and 60th percentiles of physical component summary (PCS) score distribution (ß = - 2.60, p = 0.006; ß = - 2.01, p = 0.005; ß = - 1.86, p = 0.001; ß = - 1.98, p = 0.009, respectively). A similar result was observed only in the 40th percentile of PCS distribution for the progressive overweight group (ß = - 1.03, p = 0.022). In addition, the progressive overweight group in males showed a positive association with the upper tail of mental component summary (MCS) score distribution specifically for the 90th percentile (ß = 1.15, p = 0.036). Regarding females, the current results indicated that the 90th percentile of MCS distributions was decreased in the persistent increasing overweight/obese group for females (ß = - 1.83, p = 0.024). In addition, the progressive overweight group in females had a positive association with lower (30th and 40th) percentiles of PCS distribution (ß = 1.29, p = 0.034, and ß = 1.15, p = 0.030, respectively). CONCLUSION: A sex-specific conditional association between developmental BMI trajectories from childhood and HRQoL in young adulthood was observed in physical and mental HRQoL.

Analysis of tamoxifen and its main metabolites in plasma samples of breast cancer survivor female athletes: Multivariate and chemometric optimization.

A sensitive method based on liquid chromatography combined with a diode array detector was developed and validated to simultaneously determine tamoxifen, and its active metabolites N-desmethyltamoxifen, 4-hydroxytamoxifen, and endoxifen in human plasma samples. The green and sustainable vortex-assisted dispersive liquid-phase microextraction technique based on the natural hydrophobic deep eutectic solvent was used for the extraction and preconcentration of the analytes. Chemometrics and multivariate analysis were used to optimize the independent variables including the type and volume of deep eutectic solvent, extraction time, and ionic strength. Under optimal conditions, calibration curves were linear in a suitable range with the lower limits of quantification (0.8-10.0 µg/L), which covered the relevant concentrations of the analytes in plasma samples for a clinical study. Intra- and interday precision evaluated at three concentrations for the analytes were lower than 8.2 and 12.1%, respectively. Accuracy was in the range of 94.9-104.7%. The applicability of the developed method on human plasma samples illustrated the range 45.1-72.8, 98.4-128.3, 0.9-1.2, and 2.7-6.1 µg/L for tamoxifen, N-desmethyltamoxifen, 4-hydroxytamoxifen, and endoxifen, respectively. The validated method can be effective for the pharmacokinetics, pharmacodynamics, and therapeutic drug monitoring studies of tamoxifen and its main metabolites in biological fluids.

The effect of behavioral therapy based counseling with anxious mothers on their infants' colic: a randomized controlled clinical trial.

BACKGROUND: Given the possible effect of maternal anxiety on the severity of colic pain in infants, this study aimed to investigate the effects of behavioral therapy counseling on infantile colic (primary outcome), maternal anxiety, and mother-infant attachment (secondary outcomes) in anxious mothers with colicky infants. METHOD: This randomized controlled clinical trial was conducted on 46 anxious mothers of 2-6-weeks-old exclusively breastfed colicky infants who had a score of 112 and above according to the Postpartum Specific Anxiety Scale (PSAS), reffered to the pediatric clinics of Al-Zahra, Taleghani and Children Hospitals of Tabriz, Iran. The participants were randomly assigned to the intervention (n = 23) and control (n = 23) groups using randomized block design. Mothers in the intervention group attended 8 systematic desensitization counseling sessions (2-3 sessions per week). Those in the control group received routine care. The researcher completed the Postpartum Specific Anxiety Scale (PSAS), Mother-Infant Attachment Questionnaire (MIAQ), and Infant Colic Scale (ICS) by interviewing the participants before and two weeks after the intervention. RESULTS: There was no significant difference between the intervention and control groups in the socio-demographic profile of participants. After the intervention, the mean postpartum anxiety score of women in the intervention group was significantly lower than that of those in the control group (Mean Difference (MD) = 22.5, 95% Confidence Interval (CI) = 2.3 to 42.7; p = 0.029). The mean infant colic score of the infants of mothers in the intervention group was insignificantly lower than that of those in the control group (MD = -2.9, 95% CI = -8.3 to 2.4; p = 0.271). In addition, no significant difference was observed between the two groups in terms of their mean mother-infant attachment scores (MD = -0.04, 95% CI = -3.1 to 0.3; p = 0.976). CONCLUSION: Behavioral therapy counseling effectively reduced postpartum anxiety in women with colicky infants; however, this reduction did not lead to a significant decrease in the infants' colic pain. Therefore, health care providers are recommended to use this counseling method in combination with other effective counseling approaches to promote mental health of these mothers. TRIAL REGISTRATION: IRCT Registration Number: IRCT20111219008459N14, registered on 08/10/2020. https://irct.ir/user/trial/45949/view.

Does Motivational Interviewing Improve the Weight Management Process in Adolescents? A Systematic Review and Meta-analysis.

BACKGROUND: Due to the complex nature and high heterogeneity of motivational interviewing (MI) trials, available data on the effectiveness of these interventions on weight management in the early years of life is not yet conclusive. This study aimed to (1) evaluate the effectiveness of MI-based interventions on modifying obesity-related behaviors and consequently controlling weight in adolescents, and (2) determine characteristics of participants and interventions through sub-group analysis. METHODS: Electronic databases, i.e., Medline, Elsevier, ISI, Cochrane Central Register of Controlled Trials (Clinical Trials), PsycINFO, and subject-related key journals were searched for randomized controlled trials that investigated the effect of MI-based interventions on weight management in overweight/obese adolescents. Primary outcomes were BMI, BMI Z-score, waist circumference, and fat percentage. Secondary outcomes were related behaviors (dietary intake and physical activity) and cognitive abilities (self-efficacy, self-regulation, self-control). Of the 3673 studies initially screened for eligibility, nineteen studies met the inclusion criteria and eighteen studies were entered in the meta-analysis. Meta-regression and sub-group analyses were conducted to control the high heterogeneity of studies. Sensitivity analysis has been conducted based on the Cochrane guidelines using the leave-one-out methods. RESULTS: MI-based interventions did not affect on all primary outcomes, including BMI, BMI Z-score, waist circumference, and fat percentage; however, in terms of secondary outcomes, only sugary beverage intake was reduced in adolescents (SMD = - 0.47, K = 3, I2 = 26.2%). Physical activity and cognitive variables were not considered in the current analysis due to limited data and high heterogeneity in measurements and reports. In addition, findings of sensitivity results showed that MI could significantly reduce waist circumference among adolescents (SMD = - 0.51, 95% CI - 0.91 to - 0.11). In terms of subgroup analysis, our results showed that various characteristics of participants (age, sex, weight status) and interventions (parental involvement, study duration, fidelity assessment, type of the control groups) could affect related primary and secondary outcomes among adolescents. CONCLUSION: MI-based behavioral interventions had minor effects on reducing sugary beverage intake in all adolescents while a reduction in central obesity was noted predominantly among girls and those with complete participation. The current results indicate that the main characteristics influencing goal achievement in MI interventions are the age of participants, MI fidelity assessment, parental involvement, duration of interventions, and type of the control groups.

Efficacy of low-level laser therapy on pain, disability, pressure pain threshold, and range of motion in patients with myofascial neck pain syndrome: a systematic review and meta-analysis of randomized controlled trials.

Low-level laser therapy (LLLT) is one of recent modalities for treatment of myofascial neck pain (MNP). Several RCTs have been conducted on its effectiveness. The aim of this comprehensive meta-analysis was to evaluate the effectiveness of LLLT on MNP. Electronic databases were searched for identifying eligible studies comparing the effectiveness of LLLT using any wavelength with placebo or active control in myofascial neck pain up to June 2022. Data related to pain intensity, pain pressure threshold (PPT), range of motion (ROM), and disability was analyzed as a pooled estimate of mean difference or standard mean difference (SMD) with 95% confidence intervals (CIs) using random/fixed-effect model. Funnel plot and Egger's linear regression test were also conducted to examine the risk of publication bias. A total of 13 randomized controlled trials were included in this systematic review and meta-analysis. The data assessing laser effectiveness on different outcomes of 556 patients were considered for meta-analysis. Pooled results revealed that LLLT was significantly effective in pain reduction (MD = - 1.29, 95% CI = - 2.36; - 0.23, P < 0.001). Also, secondary outcomes including PPT (SMD of 2.63, 95% CI = 0.96; 4.30, P < 0.01) and right bending ROM (SMD of 3.44, 95% CI = 0.64; 6.24, P < 0.01) were improved, while disability (MD of - 7.83, 95% CI = - 17.1; 0.08, P = 1.34) did not improve significantly after LLLT. Our meta-data revealed that LLLT may reduce myofascial neck pain and its related outcomes. LLLT is suggested to be used by clinicians along with other therapies such as manual and exercise therapy.

Risk of hypertension in school-aged children undergoing a long-term community-based lifestyle intervention: Tehran Lipid and Glucose Study.

Childhood hypertension which increases the risk of cardiovascular diseases in adulthood is becoming more prevalent. For the first time in the Middle-East region, this study aimed to assess the long-term effectiveness of a community-based lifestyle intervention on the incidence of hypertension in school-aged children during 16 years of follow-up. This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS). Participants were 2080 children aged 8-18 years with normal blood pressure who were under the coverage of three health care centers selected using multistage cluster random sampling method. One of the health care centers far from the other two was selected for implementing lifestyle intervention (1053 children, 48.2% boys). Triennial examinations were conducted, and survival Cox models were used to assess intervention effects on the incidence of hypertension in boys and girls. Crude incidence rates (per 1000 person-years) of hypertension were 8.11, 3.7, and 5.8 among boys, girls, and the total sample, respectively. Our results showed that HTN has occurred significantly less (P = 0.025) in the intervention group than in the control group, only in female participants. These results remained significant even after adjusting for individuals' and parental characteristics (P = 0.033). Although the risk of hypertension in boys was more than twice that observed in girls, the effectiveness of the recent community-based healthy lifestyle intervention was observed only in girls and not in boys. Further studies are needed to understand gender differences in promoting the effectiveness of similar future programs. The TLGS is registered at Iran Registry for Clinical Trials, a WHO primary registry (http://irct.ir; IRCTID: IRCT138705301058N1).

Effect of resveratrol administration on ovarian morphology, determined by transvaginal ultrasound for the women with polycystic ovary syndrome (PCOS).

Intake of resveratrol has been associated with improved ovarian morphology under in vitro and in the animal models; however, this finding has not been confirmed in trials. The aim of our study was, therefore, to use a placebo-controlled approach with the detailed assessment of the ovarian morphology by applying transvaginal ultrasound to examine the effectiveness of this therapeutic approach in this group of women. The mean age of all participants was 28·61 (sd 4·99) years, with the mean BMI of 28·26 (sd 5·62) kg/m2. Resveratrol therapy, as compared with placebo, was associated with a significantly higher rate of improvement in the ovarian morphology (P = 0·02). Women who received resveratrol had a more dominant follicle than those getting placebo, with a significant reduction in the ovarian volume (P < 0·05). However, the number of follicle count per ovary (FNPO), stromal area (SA), ovarian echogenicity and distribution of follicles were not significantly altered (P > 0·05). Forty-one women with polycystic ovary syndrome (PCOS) were randomly assigned (1:1) to 3 months of daily 1000 mg resveratrol or placebo. Random assignment was done by blocked randomisation. Our primary endpoints were the change in the ovarian volume, SA and antral FNPO from the baseline to 3 months. Secondary endpoints were improvement in the distribution of follicles and ovarian echogenicity. Differences between the resveratrol and control groups were evaluated by Chi-square, Fisher's exact test and repeated-measures ANOVA. Treatment with resveratrol significantly reduced the ovarian volume and polycystic ovarian morphology, thus suggesting a disease-modifying effect in PCOS.

Effects of supplementation with main coffee components including caffeine and/or chlorogenic acid on hepatic, metabolic, and inflammatory indices in patients with non-alcoholic fatty liver disease and type 2 diabetes: a randomized, double-blind, placebo-controlled, clinical trial.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is much more frequent and more severe, including cirrhosis, hepatocellular carcinoma in patients with type 2 diabetes. Coffee is a complex beverage with hundreds of compounds whereas caffeine and chlorogenic acid are the most abundant bioactive compounds. The published epidemiological data demonstrating beneficial associations between all categories of coffee exposure and ranges of liver outcomes are rapidly growing; however, the main contributors and cause-effect relationships have not yet been elucidated. To address existing knowledge gaps, we sought to determine the efficacy and safety of 6 months chlorogenic acid and/or caffeine supplementation in patients with type 2 diabetes affected by NAFLD. METHODS: This trial was carried out at two Diabetes Centers to assess the effects of supplementation with daily doses of 200 mg chlorogenic acid, 200 mg caffeine, 200 mg chlorogenic acid plus 200 mg caffeine or placebo (starch) in patients with type 2 diabetes and NAFLD. The primary endpoint was reduction of hepatic fat and stiffness measured by FibroScan, and changes in serum hepatic enzymes and cytokeratin - 18 (CK-18) levels. Secondary endpoints were improvements in metabolic (including fasting glucose, homeostasis model assessment-estimated insulin resistance (HOMA-IR), hemoglobin A1c (HBA1C), C-peptide, insulin and lipid profiles) and inflammatory (including nuclear factor k-B (NF-KB), tumor necrosis factor (TNF-α), high sensitive- C reactive protein(hs-CRP)) parameters from baseline to the end of treatment. RESULTS: Neither chlorogenic acid nor caffeine was superior to placebo in attenuation of the hepatic fat and stiffness and other hepatic outcomes in patients with diabetes and NAFLD. Except for the lower level of total cholesterol in caffeine group (p = 0.04), and higher level of insulin in chlorogenic acid plus caffeine group (p = 0.01) compared with placebo, there were no significant differences among the treatment groups. CONCLUSION: These findings do not recommend caffeine and/or chlorogenic acid to treat NAFLD in type 2 diabetes patients. TRIAL REGISTRATION: IRCT201707024010N21 . Registered 14 September 2017.

Postprandial glycemia and insulin secretion following glutamine administration: A randomized controlled trial.

Objective: The objective of the present study is to investigate the effects of glutamine administration on postprandial glycemia, insulin, and C-peptide concentration in patients with type 2 diabetes. Methods: A randomized, double-blind, placebo-controlled trial was conducted on patients with type 2 diabetes so that 33 subjects were recruited in each group. The patients were randomly allocated to receive either 30 g/d glutamine or placebo (with instructions to take in half glass of ice-cold water 5 to 10 min before each main meal) for 6 weeks. Postprandial C-peptide, insulin, and glucose were measured at the baseline and at the end of the study at 30 and 90 min after consuming a meal comprising wheat-cake and reduced fat milk. Results: The repeated measures ANOVA revealed no significant difference between the groups for glucose and insulin after 6 weeks of intervention (p > 0.05). However, C-peptide was reduced in both intervention groups at all measurement points. Between-group differences remained significant by the end of the study (p = 0.02). Conclusions: Glutamine supplementation before each main meal does not represent an effective nutritional strategy to improve postprandial glycemic control or postprandial insulin secretion in type 2 diabetes patients.

Usefulness of prolactin measurement in inferior petrosal sinus sampling with desmopressin for Cushing's syndrome.

Background: Bilateral inferior petrosal sinus sampling (IPSS) is used to distinguish pituitary from ectopic adrenocorticotropin (ACTH) excess in patients with ACTH-dependent Cushing's syndrome. Our objective was to examine the utility of prolactin measurement during IPSS with desmopressin (DDAVP) stimulation in localization of the source of ACTH excess.Method: Retrospective review of 20 patients with ACTH-dependent Cushing's syndrome who underwent IPSS with DDAVP stimulation. Baseline, DDAVP-stimulated, and prolactin-normalized ACTH IPS:P (inferior petrosal sinus to peripheral) ratios were calculated. Cut-off values for each test were obtained from receiver-operating characteristic (ROC) curve analysis.Results: Fifteen patients had Cushing disease (CD), and five were diagnosed with ectopic ACTH syndrome (EAS). For the baseline ACTH IPS:P ratio of ≥2, the diagnostic sensitivity (80%), specificity (100%), positive predictive value (PPV) (100%) and negative predictive value (NPV) (62.5%) were calculated. These values for DDAVP-stimulated IPS:P ACTH ratio ≥ 3, were 86.7%, 100%, 100% and 71.4%, respectively. The corresponding value for the prolactin-normalized ACTH IPS:P ratio ≥ 0.8 were 86.6%, 80%, 92.8% and 66.7%. The cut-off value for the baseline, DDAVP-stimulated and prolactin-normalized ACTH IPS:P ratios were 1.76, 3.9, and 0.33, respectively.Conclusion: Prolactin-normalized ACTH IPS:P ratio measurement showed comparable sensitivity and less specificity than baseline/DDAVP-stimulated IPS/P ACTH ratios. Moreover, when baseline and stimulated IPS/P ACTH tests were discordant, prolactin-normalized ACTH IPS: P ratio correctly localized the source of ACTH excess. The sensitivity of the test increased, applying a prolactin-normalized ACTH IPS: P ratio ≥0.33.

Magnetic solid phase extraction based on poly(ß-cyclodextrin-ester) functionalized silica-coated magnetic nanoparticles (NPs) for simultaneous extraction of the malachite green and crystal violet from aqueous samples.

In this research, an efficient sorbent based on poly(ß-cyclodextrin-ester)-functionalized silica-coated magnetic nanoparticles (MNPs-CDP) was prepared and used for magnetic solid-phase extraction of the malachite green (MG) and crystal violet (CV) from water samples prior to their determination by high-performance liquid chromatography-ultra violet detection (HPLC-UV). The synthesized nanoparticles were characterized by the field emission-scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). Of course, the factors, which could influence the extraction efficiency like pH, sorbent amount, salt content, extraction time, desorption time, eluent type, and volume and sample volume, were optimized by response surface methodology. Then, for both of MG and CV, good linearity (0.1-200 µg L-1, r2 ≥ 0.99) was achieved under the optimized conditions. The limits of detection (LODs) and the limits of quantification (LOQs), for both of MG and CV, were 0.03 µg L-1 and 0.1 µg L-1, respectively. Precision of the method expressed as the relative standard deviations (RSDs) at concentration level of 100 µg L-1 was 5.6 and 4.2 for MG and CV, respectively. Ultimately, usability of proposed method was investigated by analysis of CV and MG in tap water, fish pond water, and the lake water, and the satisfactory recoveries were obtained in the range of 92-100.5%.

On Stability of Specific Adhesion of Particles to Membranes in Simple Shear Flow.

Adhesion of carrier particles to the luminal surface of endothelium under hemodynamic flow conditions is critical for successful vascular drug delivery. Endothelial cells (ECs) line the inner surface of blood vessels. The effect of mechanical behavior of this compliant surface on the adhesion of blood-borne particles is unknown. In this contribution, we use a phase-plane method, first developed by Hammer and Lauffenburger (1987, "A Dynamical Model for Receptor-Mediated Cell Adhesion to Surfaces," Biophys. J., 52(3), p. 475), to analyze the stability of specific adhesion of a spherical particle to a compliant interface layer. The model constructs a phase diagram and predicts the state of particle adhesion, subjected to an incident simple shear flow, in terms of interfacial elasticity, shear rate, binding affinity of cell adhesive molecules, and their surface density. The main conclusion is that the local deformation of the flexible interface inhibits the stable adhesion of the particle. In comparison with adhesion to a rigid substrate, a greater ligand density is required to establish a stable adhesion between a particle and a compliant interface.

Phosphate-solubilizing bacteria and silicon synergistically augment phosphorus (P) uptake by wheat (Triticum aestivum L.) plant fertilized with soluble or insoluble P source.

Phosphorus (P) deficiency is one of the major problems in agricultural soils for crop production around the world. Use of silicon (Si) and phosphate-solubilizing bacteria (PSB) is known as one of the most effective and economical ways for increasing P availability and improving P use efficiency under low P conditions. However, little is known about the alleviative role of Si and PSB together in mitigating P-deficiency stress and in improving P use efficiency in Triticum aestivum L. (wheat), as one of the most important crop plants worldwide. Consequently, aim of the research was to study the combined and single effects of Si (0, 150, 300, and 600 mg kg-1 added as silicic acid) and PSB (B0, Bacillus simplex UT1, and Pseudomonas sp. FA1) on P uptake by wheat plant fertilized with soluble or insoluble P (Esfordi rock phosphate, RP) in a completely randomized design with factorial arrangement through a perlite potted experiment. In addition, the effects of various treatments on wheat shoot and root dry weight, activity of catalase, superoxide dismutase, and peroxidase enzymes, and the uptake of Si and potassium (K) by this plant were also investigated. Both shoot and root biomass of wheat plants were markedly reduced when grown in RP-fertilized medium compared with those grown in soluble P-fertilized medium. The PSB strains and Si levels independently improved all the aforementioned parameters. Application of Si to wheat plants grown in soluble P or insoluble P medium markedly enhanced P use efficiency. According to the results of this study, Si not only increased the uptake of P from sparingly soluble-P source (RP), but also enhanced uptake of P from water-soluble P source. Both Pseudomonas sp. FA1 and B. simplex UT1 showed a considerable role in improvement of root and shoot biomass and uptake of P (and K and Si) under both soluble and insoluble P fertilization conditions with Pseudomonas sp. FA1 being more effective than B. simplex UT1. However, the combined application of the PSB with Si resulted in the greatest enhancement in wheat plant P uptake and other measured parameters. Addition of 600 mg Si kg-1 and Pseudomonas sp. FA1 significantly increased the P shoot concentration of wheat plant fertilized with RP to an adequate level (>0.3%) in the range of P-fertilized plants. Therefore, in addition to PSB application, Si should be considered as soil amendment in agricultural soils deficient in plant available Si as a means of sustainable agriculture with respect to possible savings of scarce P resources (P-fertilizers). The information on the availability of P following PSB and Si addition to plant growth medium may help in better management of P fertilization.

Synthesis of N-doped TiO2/SiO2/Fe3O4 magnetic nanocomposites as a novel purple LED illumination-driven photocatalyst for photocatalytic and photoelectrocatalytic degradation of naproxen: optimization and different scavenger agents study.

N-doped TiO2/SiO2/Fe3O4 as a new magnetic photocatalyst that is active in visible light has been prepared by simple sol-gel method. The prepared samples were characterized by XRD, FESEM, EDX, TEM, BET, BJH, VSM, XPS, FT-IR, and DRS-UV/Vis analysis. The photocatalytic effect of synthesized samples on naproxen degradation was studied. The operational parameters were optimized through central composite design to achieve maximum efficiency. The optimum values for maximum efficiency were obtained at pH of 4.29, catalyst mass of 0.06 g, naproxen concentration of 9.33 mg L-1, and irradiation time of 217.06 min. At these optimum conditions, the maximum photocatalytic degradation percentages of naproxen were found to be 96.32% at desirability function value of 1.0. Coupling the electrical current with the photocatalytic process proved that the electrical current was considerably efficient in decreasing the degradation time of removing the naproxen from aqueous solutions. The photocatalytic activity of the nanoparticles was also studied under sunlight. Considering the results provided by UV-Vis spectrophotometry and total organic carbon, it was found that the prepared samples are extraordinarily efficient to degrade naproxen under both purple LED and solar lights. Furthermore, the effect of different scavenger agents on naproxen degradation has been studied.

Polydispersity controls the strength of semi-flexible polymer networks.

The classical theory of polymer elasticity is built upon the assumption of network monodispersity-the premise that polymer networks are comprised of sub-chains of equal length. The crosslinking of biopolymers, however, is a random process and the resultant networks are likely to be polydisperse. The effect of structural polydispersity on the mechanical behavior of biopolymer networks is not well understood. The purpose of this contribution is to show how network polydispersity controls mechanical behavior and the ultimate properties of crosslinked semi-flexible filaments at finite deformations. The proposed micromechanical continuum model is based on the force-elongation relation of individual chains of different lengths. It is shown that the mechanical strength of the network is controlled by the finite-extensibility of filaments and the degradation of shorter filaments at relatively small stretches. The progressive failure of filaments continues and eventually determines the ultimate strength of the network. The predicted stress-stretch behaviors are in reasonable agreement with the experimental data for connective tissues.

Facile preparation of multifunctional carbon nanotube/magnetite/polyaniline nanocomposite offering a strong option for efficient solid-phase microextraction coupled with GC-MS for the analysis of phenolic compounds.

The aim of this study was to synthesize a highly efficient organic-inorganic nanocomposite. In this research, the carbon nanotube/magnetite/polyaniline nanocomposite was successfully prepared through a facile route. Monodisperse magnetite nanospheres were prepared through the coprecipitation route, and polyaniline nanolayer as a modified shell with a high surface area was synthesized by an in situ growth route and characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The prepared nanocomposite was immobilized on a stainless-steel wire for the fabrication of the solid-phase microextraction fiber. The combination of headspace solid-phase microextraction using carbon nanotube/magnetite/polyaniline nanocomposite fiber with gas chromatography and mass spectrometry can achieve a low limit of detection and can be applied to determine phenolic compounds in water samples. The effects of the extraction and desorption parameters including extraction temperature and time, ionic strength, stirring rate, pH, and desorption temperature and time have been studied. Under the optimum conditions, the dynamic linear range was 0.01-500 ng/mL and the limits of detection of phenol, 4-chlorophenol, 2,6-dichlorophenol, and 2,4,6-trichlorophenol were the lowest (0.008 ng/mL) for three times. The coefficient of determination of all calibration curves was more than 0.990.

Association between low bone mass and the serum RANKL and OPG in patients with nephrolithiasis.

BACKGROUND: Nephrolithiasis is a risk factor for Osteopenia and osteoporosis. Receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) regulate bone remodeling and osteoclastogenesis. This study aimed to evaluate the relation between serum OPG, RANKL concentration, and bone mineral density (BMD) in patients with kidney stone disease. METHODS: Forty-four nephrolithiasis patients with either low bone mass or normal BMD (considered control group) were enrolled in this study. BMD was measured at lumbar spine (L1-L4) and femoral neck by dual-energy X-ray absorptiometry (DEXA). The serum OPG and RANKL were determined using the ELISA method. RESULTS: The median levels of serum OPG were significantly higher in nephrolithiasis patients with low bone mass compared to the nephrolithiasis patients with normal BMD (3.9 pmol/l versus 3.1 pmol/l; P = 0.03), respectively. Negative correlation was detected between bone densities of femoral neck and OPG in patients with nephrolithiasis (r = -.0344, P = 0.02). CONCLUSION: The present study showed that high serum fasting OPG levels may be indicative of femoral neck BMD in patients with nephrolithiasis.