Search

Background and Objectives: The present study aimed to investigate the effects of eight weeks of taking nano-curcumin and performing aerobic exercise on the expression of Atrogin-1 and Murf-1 genes in the soleus muscle of male Wistar rats. Materials and Methods: This experimental study was conducted on 32 rats. Aerobic exercises were performed 5 times per week, and nano-curcumin was administered to rats at 80 mg per kg. The real-time PCR (Polymerase chain reaction) technique was employed to measure gene expression, and two-way analysis of variance (ANOVA) was used to analyze the data. Results: The results showed that aerobic exercise significantly decreased the expression levels of the MuRF-1 and Atrogin-1 genes (p<0.05). In addition, nano-curcumin supplementation without aerobic exercise also reduced the expression levels of the mentioned genes (p<0.05). Conclusion: The results of this study indicated that nano-curcumin supplementation alone decreased the expression levels of the two mentioned genes and so did aerobic exercise alone. However, their interaction effects were not significant on the expression level of the Atrogin-1 gene. [ABSTRACT FROM AUTHOR]

Background: Refractory angina is a clinical diagnosis which implies to chronic pain due to coronary artery insufficiency and it is often resistant to routine cardiac treatment. The present study conducted to compare changes in refractory angina frequencies during 7 weeks treatment by enhanced external counterpulsation (EECP) in coronary artery disease (CAD) patients with and without diabetes.Methods: In this retrospective study, 94 CAD patients (30 diabetics vs. 64 nondiabetics) who referred to cardiac rehabilitation department of Imam Ali Hospital of Kermanshah, Iran, during January 2006-2014 were assessed. The interventional method was EECP and medical records and frequencies of self-reported chest pain were research instruments. Data were analyzed through Chi-square test, mixed repeated measures, and Bonferroni test.Results: Frequencies of pain in both diabetic and nondiabetic groups during 7 weeks had linear reduction, but this reduction was significant only among nondiabetic patients (P < 0.0005). Furthermore, the significant reduction in frequencies of pain among this group begins after the 5th week.Discussion: Diabetes is one of the obstacles to the successful control of pain frequencies by the EECP in patients with CAD. Future studies may pay attention to the confounding role of diabetes in improving the severity of chest pain. [ABSTRACT FROM AUTHOR]

[Display omitted] This study aims to overcome physiological barriers and increase the therapeutic index for the treatment of glioblastoma (GBM) tumors by using Paclitaxel (PTX) loaded Poly(lactic co-glycolic acid) nanoparticles (PTX-PLGA-NPs) and Doxorubicin (DOX) loaded Poly (lactic co-glycolic acid) nanoparticles (DOX-PLGA-NPs). The hydrodynamic diameter of nanoparticles (NPs) was characterized by dynamic light scattering (DLS) which was 94 ± 4 nm and 133 ± 6 nm for DOX-PLGA-NPs, and PTX-PLGA-NPs, respectively. The zeta potential for DOX-PLGA-NPs and PTX-PLGA-NPs were −15.2 ± 0.18 mV and −17.3 ± 0.34 mV, respectively. The cytotoxicity of PTX-PLGA-NPs and DOX-PLGA-NPs was augmented compared to DOX and PTX on C 6 GBM cells. The Lactate dehydrogenase (LDH) tests for various formulations were carried out. The results indicated that the amount of released LDH was 262 ± 7.84 U.L-1 at the concentration of 2 mg/mL in the combination therapy, which was much higher than other groups (DOX-PLGA-NPs (210 ± 6.92 U.L-1), PTX-PLGA-NPs (201 ± 8.65 U.L-1), DOX (110 ± 9.81 U.L-1), PTX (95 ± 5.02 U.L-1) and PTX + DOX (67 ± 4.89 U.L-1)). MRI results of the combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs indicated that GBM tumor size decreased considerably compared to the other formulations. Also, combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs demonstrated a longer median survival of more than 80 days compared to PTX (38 days), DOX (37 days) and PTX + DOX (48 days), PTX-NPs (58 days) and DOX-NPs (62 days). The results of locomotion, body weight, rearing and grooming assays indicated that combination therapy of PTX-PLGA-NPs and DOX-PLGA-NPs had the most positive effect on the movements of rats compared to the other formulations. [ABSTRACT FROM AUTHOR]

Purpose: The size of polymeric nanoparticles is considered as an effective factor in cancer therapy due to enterance into tumor tissue via the EPR effect. The purpose of this work was to investigate the effective parameters on poly(lactic-co-glycolic acid)-paclitaxel (PLGA - PTX) nanoparticles size. Methods: We prepared PLGA-PTX nanoparticles via single emulsion and precipitation methods with variable paremeters including drug concentration, aqueous to organic phase volume ratio, polymer concentration, sonication time and PVA concentration. Results: PLGA-PTX nanoparticles were characterized by dynamic light scattering (DLS) and scanning electron microscopy (SEM). The results exhibited that the diameter of nanoparticles enhanced with increasing drug, polymer and PVA concentrations whereas organic to aqueous phase volume ratio and sonication time required to the optimization for a given size. Conclusion: The precipitation method provides smaller nanoparticles compared to emulsion one. Variable parameters including drug concentration, aqueous to organic phase volume ratio, polymer concentration, sonication time and PVA concentration affect diameter of nanoparticles. [ABSTRACT FROM AUTHOR]

Cell-penetrating peptides with the ability to escape endosomes and reach the target are of great value as delivery vectors for different bioactive cargoes and future treatment of human diseases. We have studied two such peptides, NickFect1 and NickFect51, both originated from stearylated transportan10 (PF3). To obtain more insight into the mechanism(s) of peptide delivery and the biophysical properties of an efficient vector system, we investigated the effect of different bioactive oligonucleotide cargoes on peptide–membrane perturbation and peptide structural induction. We studied the membrane interactions of the peptides with large unilamellar vesicles and compared their effects with parent peptides transportan10 and PF3. In addition, cellular uptake and peptide-mediated oligonucleotide delivery were analyzed. Calcein leakage experiments showed that similar to transportan10, NickFect51 caused a significant degree of membrane leakage, whereas NickFect1, similar to PF3, was less membrane perturbing. The results are in agreement with previously published results indicating that NickFect51 is a more efficient endosomal escaper. However, the presence of a large cargo like plasmid DNA inhibited NickFect's membrane perturbation and cellular uptake efficiency of the peptide was reduced. We conclude that the pathway for cellular uptake of peptide complexes is cargo dependent, whereas the endosomal escape efficacy depends on peptide hydrophobicity and chemical structure. For small interfering RNA delivery, NickFect51 appears to be optimal. The biophysical signature shows that the peptide alone causes membrane perturbation, but the cargo complex does not. These two biophysical characteristics of the peptide and its cargo complex may be the signature of an efficient delivery vector system. [ABSTRACT FROM AUTHOR]

Abstract: Cell-penetrating peptides (CPPs) can internalize into cells with covalently or non-covalently bound biologically active cargo molecules, which by themselves are not able to pass the cell membrane. Direct penetration and endocytosis are two main pathways suggested for the cellular uptake of CPPs. Cargo molecules which have entered the cell via an endocytotic pathway must be released from the endosome before degradation by enzymatic processes and endosomal acidification. Endosomal entrapment seems to be a major limitation in delivery of these molecules into the cytoplasm. Bacteriorhodopsin (BR) asymmetrically introduced into large unilamellar vesicles (LUVs) was used to induce a pH gradient across the lipid bilayer. By measuring pH outside the LUVs, we observed light-induced proton pumping mediated by BR from the outside to the inside of the LUVs, creating an acidic pH inside the LUVs, similar to the late endosomes in vivo. Here we studied the background mechanism(s) of endosomal escape. 20% negatively charged LUVs were used as model endosomes with incorporated BR into the membrane and fluorescein-labeled CPPs entrapped inside the LUVs, together with a fluorescence quencher. The translocation of different CPPs in the presence of a pH gradient across the membrane was studied. The results show that the light-induced pH gradient induced by BR facilitates vesicle membrane translocation, particularly for the intermediately hydrophobic CPPs, and much less for hydrophilic CPPs. The presence of chloroquine inside the LUVs or addition of pyrenebutyrate outside the LUVs destabilizes the vesicle membrane, resulting in significant changes of the pH gradient across the membrane. [Copyright &y& Elsevier]

Voltage-gated K+ channels are gated by displacement of basic residues located in the S4 helix that together with a part of the S3 helix, S3b, forms a "paddle" domain, whose position is altered by changes in the membrane potential modulating the open probability of the channel. Here, interactions between two paddle domains, KvAPp from the Kv channel from Aeropyrum pernix and HsapBKp from the BK channel from Homo sapiens, and membrane models have been studied by spectroscopy. We show that both paddle domains induce calcein leakage in large unilamellar vesicles, and we suggest that this leakage represents a general thinning of the bilayer, making movement of the whole paddle domain plausible. The fact that HsapBKp induces more leakage than KvAPp may be explained by the presence of a Trp residue in HsapBKp. Trp residues generally promote localization to the hydrophilic-hydrophobic interface and disturb tight packing. In magnetically aligned bicelles, KvAPp increases the level of order along the whole acyl chain, while HsapBKp affects the morphology, also indicating that KvAPp adapts more to the lipid environment. Nuclear magnetic resonance (NMR) relaxation measurements for HsapBKp show that overall the sequence has anisotropic motions. The S4 helix is well-structured with restricted local motion, while the turn between S4 and S3b is more flexible and undergoes slow local motion. Our results indicate that the calcein leakage is related to the flexibility in this turn region. A possibility by which HsapBKp can undergo structural transitions is also shown by relaxation NMR, which may be important for the gating mechanism. [ABSTRACT FROM AUTHOR]

Background: Isosorbide dinitrate has been broadly used in the treatment of various ischemic heart diseases. Isosorbide is a nitric oxide donor which increases blood flow to tumors through vasodilatation and consequently accelerates the access of chemodrugs to them. Furthermore, this drug has inhibitory effects on angiogenesis, tumor growth and metastasis in vivo. Moreover, its ant-inflammatory effects have also been reported. In the present study we evaluated the effects of isosorbide on the proliferative activity of fibrosarcoma WEHI-164 cell line and peripheral blood mononuclear cells (PBMCs). Methods: WEHI-164 fibrosarcoma cells and human PBMCs were cultured in complete Roswell Park Memorial Institute (RPMI) 1640 medium with 10% fetal bovine serum and 2x104 cells/mL for WEHI-164 and 2x105 cells/mL for PBMCs. The cells were then incubated at the exponential growth phase with different concentrations of isosorbide (4x10-6-1.6x10-3 M) for 24, 48 and 72 hours. Subsequently, isosorbide effects on proliferation of the cells were evaluated by trypan blue dye exclusion (TB) test and MTT assay. Statistical comparisons between groups were made by analysis of variance. Results: The proliferative activity of WEHI-164 fibrosarcoma cells and human PBMCs treated with different concentrations of isosorbide, did not show any significant difference with untreated control cells. Conclusion: The results of this study showed that isosorbide neither had any significant effects on the proliferative activity of fibrosarcoma WEHI-164 cells nor on human PBMCs. Our findings suggest that anti-tumoral effects of isosorbide reported by other investigators may be mediated through non-cytotoxic mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Several effects of the endogenous opioid peptide dynorphin A (Dyn A) are not mediated through the opioid receptors. These effects are generally excitatory, and result in cell loss and induction of chronic pain and paralysis. The mechanism(s) is not well defined but may involve formation of pores in cellular membranes. In the 17-amino acid peptide Dyn A we have recently identified L5S, R6W, and R9C mutations that cause the dominantly inherited neurodegenerative disorder Spinocerebellar ataxia type 23. To gain further insight into non-opioid neurodegenerative mechanism(s), we studied the perturbation effects on lipid bilayers of wild type Dyn A and its mutants in large unilamellar phospholipid vesicles encapsulating the fluorescent dye calcein. The peptides were found to induce calcein leakage from uncharged and negatively charged vesicles to different degrees, thus reflecting different membrane perturbation effects. The mutant Dyn A R6W was the most potent in producing leakage with negatively charged vesicles whereas Dyn A L5S was virtually inactive. The overall correlation between membrane perturbation and neurotoxic response suggests that pathogenic Dyn A actions may be mediated through transient pore formation in lipid domains of the plasma membrane. [Copyright &y& Elsevier]

Recently, much attention has been given to the problem of drug delivery through the cell-membrane in order to treat and manage several diseases. The discovery of cell penetrating peptides (CPPs) represents a major breakthrough for the transport of large-cargo molecules that may be useful in clinical applications. CPPs are rich in basic amino acids such as arginine and lysine and are able to translocate over membranes and gain access to the cell interior. They can deliver large-cargo molecules, such as oligonucleotides, into cells. Endocytosis and direct penetration have been suggested as the two major uptake mechanisms, a subject still under debate. Unresolved questions include the detailed molecular uptake mechanism(s), reasons for cell toxicity, and the delivery efficiency of CPPs for different cargoes. Here, we give a review focused on uptake mechanisms used by CPPs for membrane translocation and certain experimental factors that affect the mechanism(s). [ABSTRACT FROM AUTHOR]

Detergent-mediated reconstitution of bacteriorhodopsin (BR) into large unilamellar vesicles (LUVs) was investigated, and the effects were carefully characterized for every step of the procedure. LUVs were prepared by the extrusion method, and their size and stability were examined by dynamic light scattering. BR was incorporated into the LUVs using the detergent-mediated reconstitution method and octyl glucoside (OG) as detergent. The result of measuring pH outside the LUVs suggested that in the presence of light, BR pumps protons from the outside to the inside of the LUVs, creating acidic pH inside the vesicles. LUVs with 20% negatively charged headgroups were used to model endosomes with BR incorporated into the membrane. The fluoresceinlabeled cell-penetrating peptide penetratin was entrapped inside these BR-containing LUVs. The light-induced proton pumping activity of BR has allowed us to observe the translocation of fluorescein-labeled penetratin across the vesicle membrane. [ABSTRACT FROM AUTHOR]

Abstract: Cell-penetrating peptides (CPPs) are membrane permeable vectors recognized for their intrinsic ability to gain access to the cell interior. The hydrophobic counter-anion, pyrenebutyrate, enhances cellular uptake of oligoarginine CPPs. To elucidate CPP uptake mechanisms, the effect of pyrenebutyrate on well-recognized CPPs with varying hydrophobicity and arginine content is investigated. The cellular CPP uptake and CPP-mediated oligonucleotide delivery is analyzed by fluorescence activated cell sorting, confocal microscopy, and a cell-based splice-switching assay. The splice-switching oligonucleotide is a mixmer of 2′-O-methyl RNA and locked nucleic acids delivered as a non-covalent complex with 10-fold molar CPP excess. CPP-induced membrane perturbation on large unilamellar vesicles is investigated in calcein release experiments. We observed that pyrenebutyrate facilitates cellular uptake and translocation of oligonucleotide mediated by oligoarginine nonamer while limited effect of pyrenebutyrate on more hydrophobic CPPs was observed. By combining the different experimental results we conclude that the pathway for cellular uptake of oligoarginine is dominated by direct membrane translocation, whereas the pathway for oligoarginine-mediated oligonucleotide translocation is dominated by endocytosis. Both mechanisms are promoted by pyrenebutyrate and we suggest that pyrenebutyrate has different sites of action for the two uptake and translocation mechanisms. [Copyright &y& Elsevier]

The article highlights a research on the solution structure of 12-mer peptide FLNCCPGCCMEP with ReAsH fluorophore through nuclear magnetic resonance (NMR) spectroscopy. The study shows that the N-terminus of the 12-mer peptide is tightly constrained as suggested in the NMR results and solution structure calculations of the optimized ReAsH peptide complex. Moreover, while the fluorophore is bound, N- and C-terminal tripeptides may interact with each other.

The aim of this study was to improve the therapeutic index of chemotherapeutic drugs on glioblastoma cells through an improved co-drug delivery system. Methotrexate (MTX) and paclitaxel (PTX) were co-loaded into poly (lactic- co -glycolic acid) nanoparticles (PLGA NPs) coated with polyvinyl alcohol (PVA) and Poloxamer188 (P188). The mean size of the NPs was about 212 nm, with a zeta potential of about −15.7 mV. Encapsulation efficiency (EE%) and drug loading (DL%) were determined to be 72% and 4% for MTX and 85% and 4.9% for PTX, respectively. The prepared NPs were characterized by differential thermal analysis (DTA) and thermogravimetric analysis (TGA). Moreover, an in vitro sustained release profile was observed for both drug loaded PLGA NPs. Glioblastoma cellular uptake of the NPs was confirmed by fluorescence microscopy and cell survival rate was investigated through the 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method after 48 h of incubation showing IC 50 values of 24.5 μg·mL−1 for PTX and 9.5 μg·mL−1 for MTX for the MTX/PTX co-loaded PLGA nanoparticles coated with PVA/P188 (Co-2 NPs). Apoptosis and necrosis were also studied via flow cytometry, the lactate dehydrogenase (LDH) assay and the amount of anti-apoptotic protein (Bcl-2) expression. Blood compatibility of the co-delivery of PTX and MTX loaded PLGA NPs was investigated using a hemolysis method as well. The co-delivery of PTX and MTX loaded PLGA NPs is promising for the treatment of glioblastoma compared to their respective free drug formulations and, thus, should be further investigated. [ABSTRACT FROM AUTHOR]

Peptides able to translocate cell membranes while carrying macromolecular cargo, as cell-penetrating peptides (CPPs), can contribute to the field of drug delivery by enabling the transport of otherwise membrane impermeable molecules. Formation of non-covalent complexes between amphipathic peptides and oligonucleotides is driven by electrostatic and hydrophobic interactions. Here we investigate and quantify the coexistence of distinct molecular species in multiple equilibria, namely peptide monomer, peptide self-aggregates and peptide/oligonucleotide complexes. As a model for the complexes, we used a stearylated peptide from the PepFect family, PF14 and siRNA. PF14 has a cationic part and a lipid part, resembling some characteristics of cationic lipids. Fluorescence correlation spectroscopy (FCS) and fluorescence cross-correlation spectroscopy (FCCS) were used to detect distinct molecular entities in solution and at the plasma membrane of live cells. For that, we labeled the peptide with carboxyrhodamine 6G and the siRNA with Cyanine 5. We were able to detect fluorescent entities with diffusional properties characteristic of the peptide monomer as well as of peptide aggregates and peptide/oligonucleotide complexes. Strategies to avoid peptide adsorption to solid surfaces and self-aggregation were developed and allowed successful FCS measurements in solution and at the plasma membrane. The ratio between the detected molecular species was found to vary with pH, peptide concentration and the proximity to the plasma membrane. The present results suggest that the diverse cellular uptake mechanisms, often reported for amphipathic CPPs, might result from the synergistic effect of peptide monomers, self-aggregates and cargo complexes, distributed unevenly at the plasma membrane. [ABSTRACT FROM AUTHOR]

The chemotherapeutic drug 5-fluorouracil (5FU) is frequently used to treat a wide range of solid malignant tumors, such as colorectal, pancreatic, gastric, breast, and head and neck cancers. Its antitumoral effects are achieved by interfering with the synthesis of RNA and DNA and by inhibiting thymidylate synthase in both malignant and non-malignant cells. Therefore, it can be responsible for severe toxicities in crucial body organs, including heart, liver, kidney, and reproductive system. Given the fact that 5FU-induced reproductive toxicity may limit the clinical application of this drug, in this study, we aimed to discuss the main locations and mechanisms of the 5FU-induced reproductive toxicity. Initially, we discussed the impact of 5FU on the male reproductive system, which leads to damage of the seminiferous epithelial cells and the development of vacuoles in Sertoli cells. Although no noticeable changes occur at the histopathological level, there is a decrease in the weight of the prostate. Additionally, 5FU causes significant abnormalities in spermatogenesis, including germ cell shedding, spermatid halo formation, polynucleated giant cells, and decreased sperm count. Finally, in females, 5FU-induced reproductive toxicity is characterized by the presence of atretic secondary and antral follicles with reduced numbers of growing follicles, ovarian weight, and maturity impairment. [ABSTRACT FROM AUTHOR]

Food insecurity (FI) is a public health concern that affects health status. In this study, we aimed to investigate the FI status, and the probable link between FI and a number of risk factors related to Non-Communicable Diseases (NCDs) in Alborz Province, Iran. This was a cross-sectional study in which 983 housewives living in Alborz Province, with the age range of 18–65 years were selected randomly using a multi-stage cluster sampling method, between 2018 and 2019. Demographic Questionnaire, Household Food Insecurity Access Scale (HFIAS), International Physical Activity Questionnaire (IPAQ), Anthropometric Measurements (weight, body mass index (BMI), waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), and waist, hip, and Neck Circumferences (WC,HC, and NC)), and systolic and diastolic blood pressure (SBP and DBP) were measured. Multivariable binary logistic regressions were used to evaluate the association between mentioned variables and FI status. The prevalence of FI in the study population was 61.24 percent (95 percent CI: 58.11–64.30). In a Multivariable binary logistic regressions model, participants in the highest stages of FI had significantly lower risk of BMI (OR: 0.62 95 percent CI 0.45–1.10) (p.007), NC (OR: 0.51; 95 percent CI 0.28–0.95) (p.03), and WHR (OR: 0.50; 95 percent CI 0.29–0.88) (p.011) in comparison with food secure group. FI was highly prevalent in our study population. Despite the high prevalence of overweight and obesity, there were no significant differences in terms of weight between groups. [ABSTRACT FROM AUTHOR]

A series of cell-penetrating PepFect peptide analogues was developed by substitutions of the galanin-derived N-terminal sequence. Histidine modifications were incorporated in order to make the peptides pH-responsive. The peptides were all able to form non-covalent complexes with an oligonucleotide cargo by co-incubation in buffer. The complexes were characterized by dynamic light scattering and circular dichroism, and an assay to evaluate the peptide-cargo affinity was developed. Cellular bioactivity was studied in HeLa cells using a luciferase-based splice correction assay. In addition, the membrane interactions of the peptides in large unilammelar vesicles was studied using a calcein leakage assay. The effects of substitutions were found to be dependent of the non-modified, C-terminal sequence of the peptides; for analogues of PepFect 3 we observed an increase in membrane activity and bioactivity for histidine-containing analogues, whereas the same modifications introduced to PepFect 14 lead to a decreased bioactivity. Peptides modified with a leucine/histidine sequence were found to be pH responsive, complexes formed from these peptides were small at pH 7 and grew under acidic conditions. The most promising of the novel PepFect 3 analogues, PepFect 132 has a significantly higher bioactivity and membrane activity than the parent peptide PepFect 3. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a serious problem with a high prevalence worldwide. The weak capability of the spinal cord for regeneration in association with upregulation of inflammatory factors is two key obstacles against a full SCI repair. Curcumin is a natural substance with anti-inflammatory and neuroprotective effects. Here, we have used a combined strategy using stem cells and hybrid hydrogel scaffolds loaded with curcumin for SCI repair. Curcumin-loaded PLGA nanoparticles were prepared, characterized, and encapsulated into gelatin/alginate hydrogel scaffolds, which were then seeded by human endometrial stem cells (hEnSCs). The resulting construct was studied using in vitro and in vivo experiments on rat models. DLS, SEM, Zeta potential, and FTIR data confirmed the successful addition of curcumin to PLGA nanoparticles. SEM analyses indicated the successful addition of curcumin-loaded nanoparticles into the gelatin/alginate scaffold, as well as the adherence of the seeded EnSCs. Based on the results, the prepared constructs not only allowed the controlled release of curcumin but also could support the survival and growth of hEnSCs. Based on the results of BBB and histological experiments, the highest BBB score was related to the combined strategy, consistent with histological outcomes, in which our hEnSC-seeded gelatin/alginate scaffold containing curcumin-loaded nanoparticles led to improved structures of the white and gray matters in the SCI site, being indicative of the superior nerve fiber regeneration, compared to other studied groups. These results indicate the efficiency of the proposed method for SCI repair and broaden the scope for subsequent studies on spinal cord regeneration. [ABSTRACT FROM AUTHOR]

Background and purpose: Thyroid cancer is the most common malignancy of the endocrine. The factors involved in differentiation of thyroid nodules are highly important. This study was done to determine the relationship between serum TSH and cytology finding of thyroid nodules. Materials and methods: In this cross-sectional study, 275 patients enrolled. Complete physical examination was done and the serum TSH was measured by IRMA method. The serum T4 and T3 were also measured if the TSH was outside the normal range. In all patients thyroid ultrasound was performed. Fine Needle Aspiration (FNA) biopsy was done on all thyroid nodules and cytology results were interpreted by a pathologist. Data was then analyzed applying Stata software. Results: The mean age of the patients was 42.5±12.5 years and there were 85.8% female. The mean of BMI was 23.7±2.2 kg/m². Calcification was found in 36% of thyroid nodules and microcalcification was observed in 92%. The mean TSH level in patients with malignancy was higher than that of those with benign thyroid nodules. Each unit increase in levels of TSH increased the risk of thyroid malignancy by 23% (OR=1.23; CI: 1.01-1.5). This risk has also increased by 38% with each unit increase in BMI (OR= 1.38; CI: 1.15-1.66). Conclusion: This study suggests that serum TSH level could be used as a predictor of the probability of malignancy in thyroid nodules. [ABSTRACT FROM AUTHOR]

Single-stranded DNA (ssDNA) is characterized by high conformational flexibility that allows these molecules to adopt a variety of conformations. Here we used native polyacrylamide gel electrophoresis (PAGE), circular dichroism (CD) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy to show that cytosine methylation at CpG sites affects the conformational flexibility of short ssDNA molecules. The CpG containing 37-nucleotide PDYN (prodynorphin) fragments were used as model molecules. The presence of secondary DNA structures was evident from differences in oligonucleotide mobilities on PAGE, from CD spectra, and from formation of A-T, G-C, and non-canonical G-T base pairs observed by NMR spectroscopy. The oligonucleotides displayed secondary structures at 4°C, and some also at 37°C. Methylation at CpG sites prompted sequence-dependent formation of novel conformations, or shifted the equilibrium between different existing ssDNA conformations. The effects of methylation on gel mobility and base pairing were comparable in strength to the effects induced by point mutations in the DNA sequences. The conformational effects of methylation may be relevant for epigenetic regulatory events in a chromatin context, including DNA-protein or DNA-DNA recognition in the course of gene transcription, and DNA replication and recombination when double-stranded DNA is unwinded to ssDNA. [ABSTRACT FROM AUTHOR]

Accomplishment of efficient intracellular delivery of bioactive peptides and proteins have been reported via conjugation of peptides having membrane permeation ability (i.e., cell‐penetrating peptides [CPPs]), where a physiological uptake system of extracellular materials, endocytosis, often plays a role. When endocytosed, the bioactive peptides and proteins are encapsulated into vesicular compartment named endosomes, and have to escape into the cytosol with the help of tethered CPPs for obtaining the expected bioactivities. Therefore, CPPs having improved endosomolytic activity is necessary. We here introduce an approach to employ hemolytic peptides as a new class of CPPs, which was designed to attenuate their membrane perturbation ability on cell surfaces while recovering the membrane lytic activity under endosomal conditions (i.e., the attenuated cationic amphiphilic lytic [ACAL] peptides). This was realized by introducing negatively charged glutamic acid (Glu) residues into the potential hydrophobic face of the cationic amphiphilic peptides. The applicability of these peptides for CPPs was evaluated through the intracellular delivery of shepherdin, an apoptosis‐inducing peptide. [ABSTRACT FROM AUTHOR]