Secondary Structure Stabilization of Macrocyclic Antimicrobial Peptides via Cross-Link Swapping.

Lactam cross-links have been employed to stabilize the helical secondary structure and enhance the activity and physiological stability of antimicrobial peptides; however, stabilization of ß-sheets via lactamization has not been observed. In the present study, lactams between the side chains of C- and N-terminal residues have been used to stabilize the ß-sheet conformation in a short ten-residue analogue of chicken angiogenin-4. Designed using a combination of molecular dynamics simulations and Markov state models, the lactam cross-linked peptides are shown to adopt stabilized ß-sheet conformations consistent with simulated structures. Replacement of the peptide side-chain Cys-Cys disulfide by a lactam cross-link enhanced the broad-spectrum antibacterial activity compared to the parent peptide and exhibited greater propensity to induce proinflammatory activity in macrophages. The combination of molecular simulations and conformational and biological analyses of the synthetic peptides provides a useful paradigm for the rational design of therapeutically active peptides with constrained ß-sheet structures.

In chronic spontaneous urticaria, IgE and C-reactive protein are linked to distinct microRNAs and interleukin-31.

BACKGROUND: Chronic spontaneous urticaria (CSU) is a common and disabling disease. Assessments of IgE and C-reactive protein (CRP) are recommended in the diagnostic work-up, but the role and clinical relevance of these biomarkers are not well characterized. Moreover, it remains unknown if elevated levels of IgE or CRP are linked to CSU microRNA (miRNA) signatures or interleukin 31 (IL-31). METHODS: We measured IgE and CRP serum levels in 47 CSU patients (and 45 healthy controls) and determined CSU disease activity using the urticaria activity score (UAS7). Expression levels of miR-155 and miR-221 were assessed by RT-PCR, and IL-31 levels were determined by ELISA. RESULTS: Total IgE and CRP levels were independently increased in CSU patients. IgE and CRP levels were highest and lowest in patients with high and mild disease activity. IgE levels correlated with miR-155 levels, whereas CRP levels correlated with miR-221 levels. miR-155 and miR-221 were significantly overexpressed in CSU patients. ROC analyses linked miRNA-155 and CSU with a sensitivity of 79% and specificity of 87%, and miRNA-221 and CSU with a sensitivity of 75% and specificity of 91%. High CRP and miR-221 expression levels were linked to elevated levels of IgG anti-TPO and IL-31. CONCLUSION: IgE and CRP are useful biomarkers for disease activity in CSU, with distinct miRNA profiles. High CRP and miR-221 levels may point to autoimmune CSU and a role for IL-31.

Endothelial nitric oxide synthase Glu298Asp gene polymorphism in the cases of idiopathic thrombocytopenic purpura.

Background: Nitric oxide (NO) can induce apoptosis in megakaryocytes. Stimulatory function of NO on platelet production may be important in the pathophysiology of idiopathic thrombocytopenic purpura (ITP). NO is produced by three isoforms of NO synthase (NOS). The endothelial nitric oxide synthase (eNOS) isoform has been detected in platelets. Polymorphism of the eNOS gene, which supplies NO synthesis, changes the functions of this enzyme. In this study, the role of eNOS Glu298Asp gene polymorphism in etiopathogenesis, its course, and treatment of ITP was investigated. Methods: Sixty-six patients [51 newly diagnosed ITP (ND-ITP), 15 chronic ITP (CH-ITP), and 60 healthy controls (HC)] were enrolled in this study. Results: In all patients, the frequency of the GT genotype was 48.5%. The frequency of the GG genotype was determined to be 40.9% and the TT genotype was 10.6%. The most common allele in all patients was the G allele. eNOS Glu298Asp gene polymorphism might be a risk factor in the etiopathogenesis of ITP. Patients with the GG genotype were thought to have a high intention for CH-ITP. Patients with the GG genotype responded effectively to medical treatment using IVIG therapy. The presence of the G allele was observed to have a positive effect on the medical treatment of patients with CH-ITP, whereas the T allele exhibited a negative effect. Conclusion: In the present study, a significant correlation was found between ITP and eNOS Glu298Asp gene polymorphism. This correlation suggested that eNOS Glu298Asp gene polymorphism might be a risk factor in the ethiopathogenesis of ITP.

Serial measurement of soluble endoglin for risk assessment at the diagnosis of fetal growth restriction.

AIM: In this study, we aimed to investigate the soluble endoglin (sEng) levels in pregnant women with fetal growth restriction (FGR) and to examine the possible relation of the sEng levels with the time remaining to delivery and maternal and fetal complications. METHODS: A total of 42 pregnant women diagnosed with FGR were retrospectively reviewed. Using the maternal blood samples it is at the collected 24-37 gestational weeks, the sEng levels were measured. Fetal biometry measurements, umbilical artery, uterine artery, middle cerebral artery Doppler indices were documented. RESULTS: Of all patients, 17 (40%) were diagnosed with early-onset FGR, while 25 (60%) were diagnosed with late-onset FGR. Abnormal Doppler findings were present in 25 (60%) patients. Of 42 newborns, 18 (42%) were hospitalised in the neonatal unit. The mean sEng level calculated by taking the average of the first and second blood samples was 63.24 ± 49.83 ng/mL. There was no statistically significant difference in the mean sEng levels between those who gave birth within four, three, and two weeks after the diagnosis of FGR and those who did not. There was a positive significant correlation between the mean sEng levels and systolic blood pressure (r = 0.319, P = .04). CONCLUSIONS: We did not find a statistically significant relationship between the sEng level and the time remaining to the time of delivery in pregnant women with FGR. We found no statistically significant difference in sEng level between the groups in pregnant women with fetuses with FGR with or without maternal and fetal complications.

Atomistic Simulation Tools to Study Protein Self-Aggregation.

Aberrant aggregation of proteins into poorly soluble, toxic structures that accumulate intracellularly or extracellularly leads to a range of disease states including Alzheimer's, Parkinson's, Huntington's, prion diseases, and type II diabetes. Many of the disease-associated amyloidogenic proteins are intrinsically disordered, which makes their experimental investigation challenging due to a limited number of experimental observables to effectively characterize their ensemble of conformations. Molecular dynamics simulations provide dynamic information with atomistic detail, and are increasingly employed to study aggregation processes, offering valuable structural and mechanistic insights. In this chapter, we demonstrate the use of all-atom molecular dynamics simulations to model the self-aggregation of a six-residue amyloidogenic peptide derived from amyloid ß, a 39-43 residue-long peptide associated with the pathogenesis of Alzheimer's disease. We provide detailed instructions on how to obtain the initial monomer conformations and build the multichain systems, how to carry out the simulations, and how to analyze the simulation trajectories to investigate the peptide self-aggregation process.

Structural and functional consequences of the STAT5BN642H driver mutation.

Hyper-activated STAT5B variants are high value oncology targets for pharmacologic intervention. STAT5BN642H, a frequently-occurring oncogenic driver mutation, promotes aggressive T-cell leukemia/lymphoma in patient carriers, although the molecular origins remain unclear. Herein, we emphasize the aggressive nature of STAT5BN642H in driving T-cell neoplasia upon hematopoietic expression in transgenic mice, revealing evidence of multiple T-cell subset organ infiltration. Notably, we demonstrate STAT5BN642H-driven transformation of γδ T-cells in in vivo syngeneic transplant models, comparable to STAT5BN642H patient γδ T-cell entities. Importantly, we present human STAT5B and STAT5BN642H crystal structures, which propose alternative mutation-mediated SH2 domain conformations. Our biophysical data suggests STAT5BN642H can adopt a hyper-activated and hyper-inactivated state with resistance to dephosphorylation. MD simulations support sustained interchain cross-domain interactions in STAT5BN642H, conferring kinetic stability to the mutant anti-parallel dimer. This study provides a molecular explanation for the STAT5BN642H activating potential, and insights into pre-clinical models for targeted intervention of hyper-activated STAT5B.

Molecular Dynamics Simulations on Nucleic Acid Binding Polymers Designed To Arrest Thrombosis.

Cancer-associated thrombosis is managed by the administration of anticoagulants and antithrombotic agents that have a high risk of inducing hemorrhagic complications. To develop safer strategies for antithrombotic therapy, in vivo activators of the intrinsic pathway, namely, cell-free nucleic acids (DNA and RNA) have been targeted with cationic, polyamine-based polymers. The cytotoxicity of the highly cationic polymers is a major drawback for their practical use, and biocompatible alternatives are in high demand. In this study, we carried out all-atom molecular dynamics simulations to systematically examine the DNA binding of polyamine-poly(ethylene glycol) (PEG) diblock polymers designed from biocompatible building blocks to inhibit the procoagulant activity of DNA. The differences in cationic charge, PEG chain length, and initial conformations of the polymers resulted in marked differences in their binding to DNA. We found that having an exposed cationic polyamine group is essential to polymer-DNA binding and a certain level of electrostatic interactions is necessary to maintain the bound state. Intrachain associations between the polyamine groups and PEG chains in some cases have led to a collapsed state of the polymer that precludes binding to DNA. This self-association is mainly due to a strong hydrogen bond between polymer polyamine and PEG groups and partly due to a partially charged semibranched polyamine group architecture. As polymer "masking" of DNA is thought to arrest DNA's prothrombotic activity, our findings highlight the desired structural features of the polymers for stronger DNA binding and provide insights into the design of novel antithrombotic agents.

Mechanistic insights into the role of glycosaminoglycans in delivery of polymeric nucleic acid nanoparticles by molecular dynamics simulations.

Delivery of polynucleotide-based therapeutics into target cells involves interactions with glycosaminoglycan chains that are located on cell membrane milieu. Mechanisms governing glycosaminoglycan-mediated changes in the nanoparticulate structures of polymer-polynucleotide complexes are unknown, and cannot be fully elucidated without atomistic level details of molecular interactions. We selected a representative nanoparticulate system consisting of a short interfering RNA (siRNA)-polyethylenimine complex, and performed all-atom molecular dynamics simulations with the prototypical glycosaminoglycan heparin. We monitored the binding between the complex constituents and the heparin, and identified key features contributing to the response of the siRNA nanoparticles to heparin. We observed three main metastable states that the siRNA nanoparticles might visit in the presence of heparin, which can be translated into different functional outcomes. By correlating our data with the widely different and seemingly contradictory roles previously assigned to glycosaminoglycans, this study provides unique insights into the discrepancies in the experimental literature concerning the role of glycosaminoglycans in the polymeric nanoparticle delivery.

Current attempts to implement siRNA-based RNAi in leukemia models.

Leukemias arise from genetic alterations in normal hematopoietic stem or progenitor cells, leading to abnormal blood population with transformed cells. With the advent of RNAi and its pharmacological mediator siRNA, it has become possible to downregulate specific drivers causing leukemias. In this review, we present unique aspects of RNAi-mediated therapy and delivery technologies. Recent updates on molecular targets and delivery systems are discussed emanating from in vitro cell models and preclinical animal models. We conclude with a view on the future of RNAi in leukemia therapy, emphasizing possible measures to achieve higher efficacy and improved safety.

A Delicate Balance When Substituting a Small Hydrophobe onto Low Molecular Weight Polyethylenimine to Improve Its Nucleic Acid Delivery Efficiency.

High molecular weight (HMW) polyethylenimine (PEI) is one of the most versatile nonviral gene vectors that was extensively investigated over the past two decades. The cytotoxic profile of HMW PEI, however, encouraged a search for safer alternatives. Because of lack of cytotoxicity of low molecular weight (LMW) PEI, enhancing its performance via hydrophobic modifications has been pursued to this end. Since the performance of modified PEIs depends on the nature and extent of substituents, we systematically investigated the effect of hydrophobic modification of LMW (1.2 kDa) PEI with a short propionic acid (PrA). Moderate enhancements in PEI hydrophobicity resulted in enhanced cellular uptake of polyplexes and siRNA-induced silencing efficacy, whereas further increase in PrA substitution abolished the uptake as well as the silencing. We performed all-atom molecular dynamics simulations to elucidate the mechanistic details behind these observations. A new assembly mechanism was observed by the presence of hydrophobic PrA moieties, where PrA migrated to core of the polyplex. This phenomenon caused higher surface hydrophobicity and surface charge density at low substitutions, and it caused deleterious effects on surface hydrophobicity and cationic charge at higher substitutions. It is evident that an optimal balance of hydrophobicity/hydrophilicity is needed to achieve the desired polyplex properties for an efficient siRNA delivery, and our mechanistic findings should provide valuable insights for the design of improved substituents on nonviral carriers.

Probing the Effect of miRNA on siRNA-PEI Polyplexes.

Delivery of small interfering RNA (siRNA) for silencing of aberrantly expressed genes is a promising therapy for the treatment of various genetic disorders. Polymeric carriers have been used in the design of efficient delivery systems to generate nanoscale siRNA polyplexes. Despite the great amount of research pursued on siRNA therapeutics, the underlying mechanisms of polyplex dissociation in cytosol are still unclear. The fate of siRNA polyplexes during intracellular stages of delivery and how the endogenous molecules may affect the integrity of polyplexes remains to be explored. In this study, we have focused on miRNA-21 as a representative anionic endogenous molecule and performed gel electrophoresis mobility shift assays, particle size and zeta (ζ)-potential analyses, and a series of all-atom molecular dynamics simulations to elucidate the effect of miRNA on siRNA-PEI polyplexes. We report a slightly better binding to PEI by miRNA than that of siRNA, and speculated that miRNA may disrupt the integrity of preformed siRNA-PEI polyplexes. In contrast to our initial speculation, however, introduction of miRNA to a preformed siRNA-PEI polyplex revealed formation of a miRNA layer surrounding the polyplex through interactions with PEI. The resulting structure is a ternary siRNA-PEI-miRNA complex, where the experimentally determined ζ-potential was found to decrease as a function of miRNA added.

Bilateral Concordance of the Fundus Hyperautofluorescent Ring in Typical Retinitis Pigmentosa Patients.

BACKGROUND: It has long been assumed that in retinitis pigmentosa, disease presentation and progression are symmetrical. This study investigated whether hyperautofluorescent ring size, one known marker of disease progression, is symmetrical in typical RP patients. MATERIALS AND METHODS: A total of 88 patients with typical retinitis pigmentosa were enrolled in the study. Each presented with a hyperautofluorescent ring when imaged at baseline with fundus autofluorescence (AF). Vertical and horizontal diameters were analyzed according to mode of inheritance and age group. Seven of 88 patients had data missing in one eye and were excluded from further analysis. RESULTS: There was no significant relationship between hyperautofluorescent ring diameter and inheritance mode. There was a tendency toward smaller ring size with age and 3.7% of subjects displayed marked asymmetry in ring size between right and left eyes, although their electroretinogram results did not differ. Overall, when patients were considered as a group, there was a high correlation between right and left eyes' horizontal and vertical diameters (r=0.99, p<0.0001; r=0.98, p<0.0001). Comparing individual patients' eyes, and accounting for measurement error, a smaller majority of patients displayed symmetry of the hyperautofluorescent ring in both dimensions (85.7% in the vertical dimension, 87.3% in the horizontal dimension). CONCLUSION: This study confirmed the highly symmetrical nature of the hyperautofluorescent ring in RP patients, except in a small subgroup. AF results, which provide less variability per image, and are consistently interpreted between different observers, may be a more sensitive and reliable method for testing symmetry than many functional tests.

Protein Tyrosine Phosphatase Non-receptor 22 Gene C1858T Polymorphism in Patients with Coexistent Type 2 Diabetes and Hashimoto's Thyroiditis.

BACKGROUND: A protein tyrosine phosphatase non-receptor type 22 (PTPN22) C1858T gene polymorphism has been reported to be associated with both Type 2 diabetes mellitus (T2DM) and Hashimoto's thyroiditis (HT) separately. However, no study has been conducted to explore the C1858T polymorphism in T2DM and HT coexistent cases up to now. AIMS: The study aimed to determine whether a relationship exists or not between the PTPN22 C1858T polymorphism and this coexistent patient group. STUDY DESIGN: Case-control study. METHODS: Peripheral blood samples from 135 T2DM patients, 102 patients with coexistent T2DM+HT, 71 HT patients and 135 healthy controls were collected into ethylenediaminetetraacetic acid (EDTA) anticoagulant tubes and genomic DNA was extracted. The PTPN22 C1858T polymorphism was analyzed using polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) methods. RESULTS: Statistically significant differences were not observed between the patient and control groups. This study demonstrated a statistically significant association between both the CT genotype and the T allele in the female patient group with coexistent T2DM+HT (CT genotype: p=0.04; T allele: p=0.045) with a statistically significant association between the CT genotype and the mean values of body mass index (BMI) and free T3 levels (FT3) (BMI: p=0.044 and FT3: p=0.021) that was detected in the patient group with coexistent T2DM+HT. The minor genotype TT was observed in none of the groups in this study. The CT genotype frequency was [number (frequency): 5 (3.8%), 7 (6.86%), 5 (7.04%), 3 (2.22%), while the T allele frequency was 5 (1.86%), 7 (3.44%), 5 (3.53%) and 3 (1.12%)] in the T2DM, T2DM+HT, HT and control groups, respectively. CONCLUSION: Our data suggest that the PTPN22 1858T allele and the CT genotype are associated with increased risk in female patients for coexistent T2DM+HT. The CT genotype was associated with high mean BMI and free T3 values in the patient group with coexistent T2DM+HT. These results demonstrate that T allele carriers were more often in the T2DM+HT group than in the T2DM group. Therefore, the combination of T2DM and HT with female gender may have higher T allele carriage in comparison to the T2DM only and male groups.

Lack of association of 1513 A/C polymorphism in P2X7 gene with susceptibility to pulmonary and extrapulmonary tuberculosis.

INTRODUCTION: Tuberculosis, is one of the a leading causes of death worldwide, is characterized by different clinical forms including: latent, localized pulmonary infection and extrapulmonary tuberculosis. Candidate gene association studies have implicated common polymophisms in genes that may influence the development of tuberculosis. This study, aimed to elucidate the role of P2X7 gene in 1513A/C polymorphism the etiopathogenesis of tuberculosis. MATERIALS AND METHODS: The study included 160 patients with tuberculosis (71 pulmonary and 89 extrapulmonary tuberculosis) and 160 healthy controls. Genomic DNA was isolated and 1513A/C polymorphism in P2X(7) gene was genotyped by PCR-RFLP method. RESULTS: Frequency of P2X7 AA genotype was 47.5% in controls and 56.87% in patients, AC frequency was 39.37% controls and 32.5% in patients, CC genotype was 13.12% in controls and 10.62% in patients. No significant difference in allele and genotype frequencies (1513A/C polymorphism) between tuberculosis patients and controls was found. CONCLUSION: The results suggest that 1513A/C polymorphism of P2X7 gene is not associated with pulmonary and extrapulmonary tuberculosis in the Eastern Turkey.

Molecular modeling of polynucleotide complexes.

Delivery of polynucleotides into patient cells is a promising strategy for treatment of genetic disorders. Gene therapy aims to either synthesize desired proteins (DNA delivery) or suppress expression of endogenous genes (siRNA delivery). Carriers constitute an important part of gene therapeutics due to limitations arising from the pharmacokinetics of polynucleotides. Non-viral carriers such as polymers and lipids protect polynucleotides from intra and extracellular threats and facilitate formation of cell-permeable nanoparticles through shielding and/or bridging multiple polynucleotide molecules. Formation of nanoparticulate systems with optimal features, their cellular uptake and intracellular trafficking are crucial steps for an effective gene therapy. Despite the great amount of experimental work pursued, critical features of the nanoparticles as well as their processing mechanisms are still under debate due to the lack of instrumentation at atomic resolution. Molecular modeling based computational approaches can shed light onto the atomic level details of gene delivery systems, thus provide valuable input that cannot be readily obtained with experimental techniques. Here, we review the molecular modeling research pursued on critical gene therapy steps, highlight the knowledge gaps in the field and providing future perspectives. Existing modeling studies revealed several important aspects of gene delivery, such as nanoparticle formation dynamics with various carriers, effect of carrier properties on complexation, carrier conformations in endosomal stages, and release of polynucleotides from carriers. Rate-limiting steps related to cellular events (i.e. internalization, endosomal escape, and nuclear uptake) are now beginning to be addressed by computational approaches. Limitations arising from current computational power and accuracy of modeling have been hindering the development of more realistic models. With the help of rapidly-growing computational power, the critical aspects of gene therapy are expected to be better investigated and direct comparison between more realistic molecular modeling and experiments may open the path for design of next generation gene therapeutics.

Generation of induced pluripotent stem cells from conjunctiva.

PURPOSE: The objective of this study was to determine whether cells from the conjunctiva could be reprogrammed into induced pluripotent stem (iPS) cells, providing an alternative source of stem cells. METHODS: We employed a doxycycline-induced reprogrammable mouse strain to generate iPS cells from conjunctiva. The identity of the stem cells was confirmed by reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence assays. Immunocytochemistry and teratoma assays are established means for scoring stem cell pluripotency. The reprogramming efficiencies of conjunctival cells and ear fibroblasts were compared. RESULTS: We confirmed the identity of the stem cells and demonstrated expression of pluripotency markers (OCT4, SOX2, NANOG, and SSEA1), as tested by RT-PCR and immunofluorescence assays. In addition, derived iPS cells differentiated successfully into embryoid bodies, and showed teratoma formation when injected into immunodeficient mice. Reprogramming conjunctival tissue is as efficient as reprogramming ear fibroblasts. Conjunctiva-iPS exhibited classic features of embryonic stem (ES) cells with respect to morphology, expression of surface antigens, and pluripotency-associated transcription factors, capacity to differentiate in vitro, and the ability to form all three germ layers in vivo. CONCLUSION: The present study demonstrated that conjunctival cells, which are readily obtained during the course of many routine conjunctival biopsies and ophthalmic procedures, can be another reliable source of iPS cells.

Effects of rosuvastatin on ADMA, rhokinase, NADPH oxidase, caveolin-1, hsp 90 and NFkB levels in a rat model of myocardial ischaemia-reperfusion.

AIM: Endothelial dysfunction, oxidative stress and inflammation are among the most important mechanisms of ischaemia-reperfusion (I/R) injury. Besides their cholesterol-lowering effects, statins are known to provide protection against myocardial dysfunction and vascular endothelial injury via nitric oxide-dependent mechanisms. The aim of this study was to investigate the effects of rosuvastatin on certain intermediates involved in the generation of nitric oxide (asymmetrical dimethyl arginin, ADMA, caveolin-1 and hsp 90), oxidative stress (rhokinase, NADPH oxidase) and inflammation (NFkB), using an in vivo model of myocardial infarction in the rat. METHODS: Adult male Sprague Dawley rats were divided into three groups (control, I/R and I/R after 15 days of rosuvastatin administration). Reperfusion was applied for 120 min following left anterior descending coronary artery ischaemia for 30 min. Caveolin-1, hsp 90 and NFkB levels were evaluated with the quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and ADMA, rhokinase and NADPH oxidase levels were evaluated with ELISA. RESULTS: While NFkB and hsp 90 levels were higher in the I/R group, their levels were significantly lower in the rosuvastatin group. While ADMA and NADPH oxidase levels significantly increased with I/R, they were lower in the rosuvastatin-treated group, but not statistically significant. Rhokinase levels were significantly lower in the rosuvastatin group. Caveolin-1 levels were not different between the groups. CONCLUSION: Our results suggest that ADMA, rhokinase, NADPH oxidase, hsp 90 and NFkB could facilitate I/R injury, and rosuvastatin significantly reduced levels of these parameters. These results indicate that rosuvastatin may have a protective role in I/R injury via mechanisms targeting inflammation, endothelial dysfunction and oxidative stress.

[Investigation of CCL1 rs159294 T/A gene polymorphism in pulmonary and extrapulmonary tuberculosis patients]. / Pulmoner ve ekstrapulmoner tüberküloz hastalarinda CCL1 rs159294 T/A gen polimorfizminin arastirilmasi

INTRODUCTION: The purpose of this study is to reveal whether CCL1 rs159294 T/A polymorphism in pulmonary and extrapulmonary tuberculosis patients pose a risk to catch tuberculosis or not. MATERIALS AND METHODS: In the study, peripheral blood samples from the control group, which includes 160 patients, who consulted to Firat University Faculty of Medicine, Pulmonology Policlinic in Elazig province and who were diagnosed with tuberculosis; and 160 healthy individuals, were taken and put into tubes containing EDTA. Each tube contained 2 cc blood samples. DNA isolation was made from these blood samples and CCL1 rs159294 T/A polymorphism was defined with PCR-RFLP analysis. RESULTS: For CCL1 rs159294 T/A polymorphism, TT genotype was found in 98 (61.3%) patients, TA genotype was found in 58 (36.3%) patients, AA genotype was found in 4 (2.5%) patients among 160 patients with tuberculosis; and TT genotype was found in 50 (70.4%) patients, TA genotype in 20 (28.2%) patients, AA genotype was found in 1 (1.4%) patient among 71 patients with pulmonary tuberculosis; TT genotype was found in 48 (53.9%) patients TA genotype was found in 38 (42.7%) patients and AA genotype was found in 3 (3.4%) patients among 89 extrapulmonary tuberculosis patients. And in control group, among 160 healthy individuals, TT genotype was found in 100 (62.5%) individuals, TA genotype was found in 58 (36.3%) individuals, AA genotype was found in 2 (1.3%) individuals and no statistically significant difference was found. CONCLUSION: CCL1 rs159294 T/A polymorphism do not form an inclination to tuberculosis in our population.

Vigabatrin-induced retinal toxicity is partially mediated by signaling in rod and cone photoreceptors.

Vigabatrin (VGB) is a commonly prescribed antiepileptic drug designed to inhibit GABA-transaminase, effectively halting seizures. Unfortunately, VGB treatment is also associated with the highest frequencies of peripheral visual field constriction of any of the antiepileptic drugs and the mechanisms that lead to these visual field defects are uncertain. Recent studies have demonstrated light exposure exacerbates vigabatrin-induced retinal toxicity. We further assessed this relationship by examining the effects of vigabatrin treatment on the retinal structures of mice with genetically altered photoreception. In keeping with previous studies, we detected increased toxicity in mice exposed to continuous light. To study whether cone or rod photoreceptor function was involved in the pathway to toxicity, we tested mice with mutations in the cone-specific Gnat2 or rod-specific Pde6g genes, and found the mutations significantly reduced VGB toxicity. Our results confirm light is a significant enhancer of vigabatrin toxicity and that a portion of this is mediated, directly or indirectly, by phototransduction signaling in rod and cone photoreceptors.

Long-term safety and efficacy of human-induced pluripotent stem cell (iPS) grafts in a preclinical model of retinitis pigmentosa.

The U.S. Food and Drug Administration recently approved phase I/II clinical trials for embryonic stem (ES) cell-based retinal pigmented epithelium (RPE) transplantation, but this allograft transplantation requires lifelong immunosuppressive therapy. Autografts from patient-specific induced pluripotent stem (iPS) cells offer an alternative solution to this problem. However, more data are required to establish the safety and efficacy of iPS transplantation in animal models before moving iPS therapy into clinical trials. This study examines the efficacy of iPS transplantation in restoring functional vision in Rpe65(rd12)/Rpe65(rd12) mice, a clinically relevant model of retinitis pigmentosa (RP). Human iPS cells were differentiated into morphologically and functionally RPE-like tissue. Quantitative real-time polymerase chain reaction (RT-PCR) and immunoblots confirmed RPE fate. The iPS-derived RPE cells were injected into the subretinal space of Rpe65(rd12)/Rpe65(rd12) mice at 2 d postnatally. After transplantation, the long-term surviving iPS-derived RPE graft colocalized with the host native RPE cells and assimilated into the host retina without disruption. None of the mice receiving transplants developed tumors over their lifetimes. Furthermore, electroretinogram, a standard method for measuring efficacy in human trials, demonstrated improved visual function in recipients over the lifetime of this RP mouse model. Our study provides the first direct evidence of functional recovery in a clinically relevant model of retinal degeneration using iPS transplantation and supports the feasibility of autologous iPS cell transplantation for retinal and macular degenerations featuring significant RPE loss.