Evaluation of the Long-Term Clinical Results of 3 Patients Implanted with the Argus II Retinal Prosthesis

This study presents the long-term clinical results of Argus II retinal prosthesis implantation in eyes with light perception and projection in 3 patients with end-stage retinitis pigmentosa. No conjunctival erosion, hypotony, or implant displacement was observed during postoperative follow-up. The electrical threshold values were lower in the macular region and higher close to the tack fixation region and peripherally. Optical coherence tomography scans showed fibrosis and retinoschisis formation at the retina-implant interface in two cases. This was attributed to mechanical and electrical effects on the tissue due to the active daily use of the system and the electrodes’ proximity to the retina. The patients were able to integrate the system into their daily lives and perform activities that they could not do before. Studies on retinal prostheses for the rehabilitation of hereditary retinal diseases are ongoing, so both social and clinical observations and experiences related to the implant are valuable

Impact of Virtual Reality Simulation in Endodontics on the Learning Experiences of Undergraduate Dental Students

Abstract: We aimed to evaluate the impact of Virtual Reality Dental Simulators (VRDS) on preclinical training in endodontics for undergraduate dental students. Purposive sampling technique was used to target undergraduate dental students at two dental schools: in Qatar and Turkey. After training on endodontic access cavity preparation on upper anterior teeth using acrylic teeth on dental mannequins and virtual reality haptic dental simulator, a questionnaire based on a combination of open- and closed-ended items was distributed to the participants. The sample included 60 dental undergraduate students. The participants reported positive experiences with VRDS and 76% considered it to be helpful in improving their fine motor skills. Endodontic access cavity preparation on VRDS was perceived to be similar to natural and acrylic teeth by 73.34% and 53% of participants, respectively. Overall, 85% of participants supported the use of VRDS training to supplement conventional training on dental mannequins but also recommended the need for improvements in VRDS training in endodontics. The findings of this study underscore the benefits of VRDS in endodontics. Future research involving larger samples from multiple institutions may help to optimize VRDS in undergraduate dental education

Improving anti-tumour activity with melatonin-stimulated mesenchymal stem cell-derived exosomes in metastatic triple-negative breast cancer

817-827The aim of this study is to increase the bioavailability of melatonin on triple-negative breast cancer (TNBC) cells by loading it into exosomes as well as comparing the therapeutic potentials of melatonin and exosome released from human adipose tissue-derived mesenchymal stem cells. TNBC is one of the most malignant tumours with highly invasive and metastatic features. It is characterized by the absence of estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2. TNBC patients can’t benefit from hormonal or trastuzumab-based therapies targeting these receptors. Exosomes are defined as naturally occurring extracellular vesicles. By enabling the transfer of molecules, exosomes play a role in cancer treatment and dynamic intercellular communication between tumour cells and adjacent stromal compartments. The half-maximum inhibitory concentration IC50 values were 30.38 μg/mL, 40.49 μg/mL and 1.5 mM at the co-administered melatonin and exosome, AT-Exo and Mel groups, respectively, for 48 h. The percentage of late-stage apoptotic induction was found to be 6.3%, 4.1% and 4.6% for TNBC exposed to co-administered melatonin and exosome (2.5 mM +100 μg/mL Mel/Exo) for 24 h, 48 h, 72 h, respectively. In conclusion, the coexistence of exosomes and melatonin represents a promising therapeutic tool that can interfere with key molecular processes such as cytotoxicity and apoptosis cascade in TNBC

Wharton Jel Kaynaklı Eksozom İzolasyonu: Metot Karşılaştırma Çalışması

Eksozomlar endozomdan köken almış, immün modülasyonda önemli role sahip, hücrelerarası etkileşimi sağlayan, nano boyutta biyomoleküllerdir. Eksozomlar tetraspanninler, proteinler, Annexin ve Rab proteinleri gibi çok çeşitli zar proteinlerine sahiptirler ve bu içeriklere sahip olmaları ile enfeksiyon, sinir sistemi, kanser ve nörodejeneratif hastalıkların tedavi ve teşhisinde kullanılmaya adaydır. Hemen hemen bütün vücut sıvılarından salınan eksozomların hem homojen hem de çok sayıda izole edilebilmesi teşhis ve tedavi için önemlidir. Bu nedenle eksozomların saflaştırılması ve tanıya yönelik spesifik eksozom izolasyonu tedavi amaçlı üretimi açısından önemli bir basamaktır. Bu çalışmada wharton jel kaynaklı ticari mezenkimal kök hücre kültür besiyerinden (medyum) farklı izolasyon metotları olan ultrasantrifüj, diferansiyel ultrasantrifüj-filtrasyon ve çökeltme (presipitasyon) metodu kullanılarak en çok sayıda ve en saf eksozom izolasyonu yapılması amaçlanmıştır. Eksozomların karakterizasyonu için; görüntülenmesi, saflığı ve boyut analizi her üç metot için belirlenmiştir. Sonuç olarak ultrasantrifüj metodunda, hem diferansiyel ultrasantrifüjfiltrasyon, hem de presipitasyon metoduna göre çok daha fazla sayıda çok daha küçük boyutta eksozom izolasyonu olduğu görülmüştür. Diferansiyel ultrasantrifüj-filtrasyon metodu sonucunda ise eksozom sayısının çok daha az olduğu ancak ultrasantrifüj yöntemi ile elde edilen eksozomlarla aynı saflıkta olduğu görülmüştür. Eksozomların hemen hemen her hastalığın tedavisinde etkin rol almalarından dolayı hastalıkların teşhisinde kullanım kolaylığı sağlamakla birlikte iyi biyo-dağılım, biyouyumluluk ve düşük immünojeniteye sahip olmaları da tedavi aşamasında avantaj sağlayacaktır.Exosomes are nano-sized biomolecules that originate from the endosome, have an important role in immune modulation, and provide intercellular interaction. Exosomes have a wide variety of membrane proteins such as tetraspanins, proteins, Annexin and Rab proteins, and they are candidates for use in the treatment and diagnosis of infections, nervous system, cancer and neurodegenerative diseases. It is important for diagnosis and treatment that exosomes released from almost all body fluids can be isolated both homogeneously and in large numbers. Therefore, the purification of exosomes and obtaining specific exosomes for diagnosis is an important step in their production for therapeutic purposes. This study aimed to isolate the most and purest exosomes by using different isolation methods, ultracentrifugation, differential centrifugation-filtration and precipitation from commercial mesenchymal stem cell culture medium derived from wharton gel. Imaging, purity and size analysis of exosome characterization was determined for methods. As a result, it was observed that as a result of the isolation with the ultracentrifuge method, a much larger number of exosomes were isolated compared to both precipitation and differential centrifugationfiltration methods. According to the differential centrifugation-filtration method, it was observed that the number of exosomes was much less, but the exosomes were of the same purity as the ultracentrifuge method. Since exosomes play an active role in treating almost every disease, they provide ease of use in diagnosing diseases, and their good biodistribution, biocompatibility and low immunogenicity will also provide an advantage in the treatment phase

Assessment of cranberry bush on MCF-7 human breast cancer cells

This research aimed to study the effects of different doses&nbsp;Viburnum opulus&nbsp;L. (VO) powder extracts at different times on human breast cancer and breast epithelial cell lines. The cytotoxic effect evalueted by using MTT method and apoptosis induction annexin V-FITC/PI staining. Comet assay was used to detect the genotoxic effect by calculating the percentage of the tail length in the DNA of both cell groups. P1 class glutathione-S-transferase (GSTP1) expression level which hasprotective feature in drug resistance metabolism was studied by immunocytochemistry method and GSTP1 and total GSTA1 metabolic protein level spectrophotometer method. This study shows that DNA damage, intracellular cytotoxicity and apoptosis have increased due to the antioxidant properties of VO powder extract.GSTP1 activities by using ethacrynic acid as substrate were found statistically significant differences between all of the groups with oneway Annova test (** P &lt;0.01).GSTP1 overexpressed in MCF-7 control cells and expression levels decreased in the MCF-7 groups that treatment with VO powder extract at different concentrations of 25, 50 and 100 µg/µL for 24, 48 and 72 h. This study provided the information that VO powder extract may be suitable for drug therapy efficacy at the molecular level.</p

Expression and biochemical significance of Piwil2 in stem cell lines

Introduction P-element induced wimpy testis-like 2 (Piwil2) is in the Piwi gene family. Piwil2 has important roles in the self-renewal mechanism of stem cell induction and progression of numerous types of human malignancies such as lung, breast, colon, prostate, and cervical cancers. Glutathione S-transferase (GST) acts as detoxification in cancer metabolism. This study aimed to investigate the effects of the stem cell protein Piwil2 on MCF10A and MCF-7 at the GST activity levels. Materials/Methods MCF-7/Piwil2 and MCF10A/Piwil2, transfected with a plasmid carrying the Piwil2 gene, and non-transfected MCF-7 and MCF10A were cultured in a complete DMEM/F12 medium. GST A1 and P1 activity was determined in these cell lines using as substrates CDNB, EA respectively. Results According to experimental results, GST P1 activity decreased in the MCF-7/Piwil2 cells as compared with the non-transfected MCF-7 cells, however, MCF-7/Piwil2 cells demonstrated increases in GST A1 (total GST) activity. The statistically significant differences were found for the comparison of non-transfected MCF-7 and MCF-7/Piwil2 (p<0,0001), for GST enzyme activities by using CDNB and EA as substrates. These results were the same for the MCF10A cell line. Discussion It is shown for the first time that transfection studies may affect GST activity at the cellular mechanism level. The study contributes to determining the effect of transfection on GST isoenzymes and also how the Piwil2 gene may affect GST activity in the stem cell line