Isopropyl Myristate-Modified Polyether-Urethane Coatings as Protective Barriers for Implantable Medical Devices

Polyurethane films have potential applications in medicine, especially for packaging implantable medical devices. Although polyether-urethanes have superior mechanical properties and are biocompatible, achieving water resistance is still a challenge. Polyether based polyurethanes with two different molecular weights (PTMO1000, PTMO2000) were prepared from 4,4’-diphenylmethane diisocyanate and poly(tetra-methylene oxide). Polymer films were introduced using different concentrations (0.5-10 wt %) of isopropyl myristate lipid (IPM) as a non-toxic modifying agent. The physical and mechanical properties of these polymers were characterised using physical and spectroscopy techniques (FTIR, Raman, DSC, DMA, tensile testing). Water contact angle and water uptake of the membranes as a function of IPM concentration was also determined accordingly. The FTIR and Raman data indicate that IPM is dispersed in polyurethane at ≤ 2wt% and thermal analysis confirmed this miscibility to be dependent on soft segment length. Modified polymers showed increased tensile strength and failure strain as well as reduced water uptake by up to 24% at 1-2 wt% IPM.     

Association of CTLA-4 gene polymorphism with Graves' disease and ophthalmopathy in Iranian patients

BackgroundThe cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene, is one of the candidate genes for susceptibility to Graves' disease. This study aimed to investigate the association of Graves' disease and Graves' ophthalmopathy with polymorphisms at position + 49 in exon 1 and positions ? 318 and ? 1147 in the promoter region of CTLA-4 gene in Iranian patients.MethodsA total of 205 unrelated Iranian patients with Graves' disease who were referred to the outpatient endocrine clinic of a large university general hospital and 103 sex-matched healthy controls were included in this study. Venous blood was obtained, genomic DNA was extracted by a salting out method, and the polymorphisms at positions + 49, ? 318 and ? 1147 of the CTLA-4 gene were determined using the PCR-restriction fragment length polymorphism method (PCR-RFLP). Genotype and allele frequencies were determined.ResultsThe frequency of the G allele at position + 49 was significantly higher in patients with Graves' disease than in the control group (27.1% vs. 15.1%, OR = 2.096, 95%CI = 1.350–3.253 and p < 0.01). Significant trends were not seen for the other two polymorphisms studied. In patients with ophthalmopathy, the frequency of the G allele at position + 49 was higher than in those without ophthalmopathy (33.8% vs. 20.0%, OR = 2.043, 95%CI = 1.304–3.202 and p < 0.01).ConclusionThe results of this study suggest that the G allele at position + 49 in exon1 of the CTLA-4 gene is associated with Graves' disease and Graves' ophthalmopathy in Iranian patients.     

Persistent urethritis and prostatitis due to Trichomonas vaginalis: A case report

The present report describes a case of persistent urethritis accompanied by prostatitis due to Trichomonas vaginalis in a young male patient. The importance of the laboratory diagnosis of trichomoniasis in persistent or recurrent urethritis (ie, testing samples from multiple sites) is highlighted, with the aim of improving the clinical recognition of this pathogen.     

A case of central retinal artery occlusion following embolization procedure for juvenile nasopharyngeal angiofibroma

A 23-year-old male patient with right nasal Juvenile Nasopharyngeal Angiofibroma (JNA) developed Central Retinal Artery Occlusion (CRAO) during embolization of the tumor using polyvinyl alcohol particles before endoscopic excision. Classic CRAO management was initiated by an ophthalmologist after 12 h. Retrospective evaluation of the angiograms revealed a tiny communication between the external carotid and ophthalmic arteries which had not been noticed before embolization. During endoscopic excision, the tumor was found to originate extraordinarily from midline structures. It was concluded that CRAO might be a rare complication of JNA embolization. Careful preoperative angiographic evaluations to detect communicating arteries and immediate ophthalmologic consultation in case of developing visual symptoms during the procedure are necessary.     

Frequency of Background and Radiation-Induced Apoptosis in Leukocytes of Individuals with α-Thalassemia Variants,Assessed by the Neutral Comet Assay

To study effects of ionizing radiation on apoptosis induction in leukocytes of α-thalassemia (α‐thal) variants compared to normal controls, venous blood samples were obtained from 10 healthy volunteers and 30 α-thal patients. Different types α-thal were diagnosed by multiplex polymerase chain reaction (PCR). Blood samples were irradiated with three Gy gamma rays, used for comet assay, immediately or 48 h after irradiation. Results show that the frequency of background as well as apoptosis in silent α-thal carriers, α-thal carriers and controls was similar but there was a significant difference between Hb H patients and other groups in the study. The increased apoptosis in Hb H patients might suggest that accumulation of β-globin and oxidative stresses are effective in causing apoptosis, and cells from these patients are more vulnerable to damage from radiation-induced toxic substances. Therefore, from α-thal patients, those with Hb H disease might be considered as radiosensitive in terms of apoptosis formation.