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Bioceramics are a fast-growing materials group, which are widely used in orthopedics, maxillofacial, dental, and reconstructive surgeries. They are produced using raw materials either from synthetic or natural sources. As naturally originated resources, the bones of sheep and cows are used after converting to calcium phosphates. Human-originated sources in the past were obtained from human cadaver bones, however now-a-days this has been discontinued. On the other hand, the “golden standard” in the reconstruction surgery has been using patients own bones, -i.e., autogenous bones, which heal better than other alternatives. Besides natural products, synthetic materials are produced from a range of inorganic raw and natural materials based on marine sources, such as corals, and other marine-derived materials (i.e., seashells, nacre). These are used to produce bioceramics and hence implants, devices, and bone grafts. Although during the last four decades a number of excellent books and book chapters have been published, no comprehensive review has been yet reported to cover the available marine materials and to indicate the related work and corresponding references to allow for both medical and ceramic scientists to access directly and open new avenues for further research on marine structures and their applications in orthopedic, maxillofacial, and reconstructive surgery areas. Hence, this review covers the general marine structures, their locations and availability in different countries and, current research on production methods of these unique structures that are difficult to fabricate synthetically. The authors are confident that this comprehensive review will be an excellent source not only for the ceramists, but also for the medical scientists.

The aim of this study is to obtain pure natural hydroxyapatite (HAp) and tricalcium phosphate (TCP) from a Goniopora spp. and from hump coral (Porites cylindrica), both sourced from Australia. Due to the nature of the conversion process, commercial coralline HAp has retained coral or CaCO3, and the structure possesses both nano- and mesopores within the interpore trabeculae resulting in high dissolution rates. To overcome these limitations, a newly patented coral double-conversion technique has been developed. The current technique involves a two-stage application route where in the first-stage complete conversion of coral to pure HAp is achieved. In the second stage, a sol-gel-derived HAp nanocoating is directly applied to cover the meso- and nanopores within the intrapore material, while maintaining the large pores. Here, we specifically investigated the morphological changes and characterized these corals prior to and after conversion. For this purpose, four groups designated as C0, C1, C2, and C3 were used. C0 is Porites, Goniopora, and cylindrica; the original coral is calcium carbonate with aragonite structure that contains proteins and polysaccharides. C1 is coral cleaned under ultrasound in bleach diluted with water. C2 is coral converted to hydroxyapatite (HAp) by hydrothermal treatment method at 200 °C under pressure in the presence of ammonium biphosphate. C3 is obtained by coating C2 with sol-gel alkoxide-derived nanohydroxyapatite to obtain a more bioactive osteoconductive material and improve mechanical properties. All groups were characterized by XRD, EDAX, DTA/TGA, and SEM. The results showed that the biaxial strengths of the C2 and C3 were significantly higher than the original coral. The work also showed the advantages of the hydrothermal conversion method and the effect of the nanocoating which is expected to improve the final bioactivity through microstructural changes of the surfaces. © 2019, Australian Ceramic Society.

Pregnant Wistar rats were exposed to ethanol under chronic conditions using the gavage method to assess the complement activation and effects of oxidative stress on fetus lymphoid organs and liver. The effects were monitored on both the 10th (G10) and the 30th (G30) day of the offspring of alcoholic mother rats. Maternal ethanol caused a significant decrease in the glutathione level, whereas malondialdehyde and carbonyl levels increased in the liver and lymphoid tissues. Na+,K+-ATPase, glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase activities in these organs also decreased. Furthermore, complement C3 and C5 activities of G10 and G30 groups were significantly higher compared with those of the control group. In conclusion, the results demonstrated that alcohol was capable of triggering damage to the membranes of the liver and lymphoid tissues of G10 and G30 groups, and C3 and C5 contributed to the development of alcohol-induced fetal tissue injury.

© 2017, Australian Ceramic Society. Nanofibrous composites of the poly(ε-caprolactone) (PCL), tricalcium phosphate (TCP), and hexagonal boron nitride (h-BN) with different compositions were manufactured by using an economical and non-complicated method called electrospinning. Produced fibrous structures showed no bead formation and had a clean surface. Characterization of the composites showed that particles were successfully mixed with polymer phase. High cell activity of SaOS-2 cells on the composites was observed with SEM images. In addition, fibrous scaffolds are biocompatible with human bone tissue and are highly degradable.

© Springer International Publishing AG 2017. During the past two decades, a number of materials and devices have been utilised in drug delivery applications. A range of biomaterials with different morphologies and pore sizes are currently utilised. For any given biomaterial or bioceramic, having an adequate control of the chemical composition as well as the critical pore sizes is important in terms of controlling the effectiveness when used to deliver drugs locally. In comparison to all currently known and used biomaterials, given the fact that it possesses chemical similarity to human bone, and most importantly its dissolution characteristics which allow for bone regeneration and growth, calcium phosphate holds a special consideration. Moreover, due to their interconnected pore structure, marine materials such as shells and coral exoskeletons show potential for applications in drug delivery due to their easy conversion to calcium phosphates with controllable dissolution rates. This chapter covers a range of current methods used specifically for natural materials that can be converted to calcium phosphates and mixed with polymeric materials as thin film or nanostructured drug, genes, protein and range of delivery and as anticancer chemotherapeutic devices.

Aim To investigate immunologic reactions after implantation of stainless steel (SS) alloy and titanium (Ti) alloy in a rat model. Macrophage and cytokine responses have been reported after the in vivo and in vitro application of different biomaterials. Material and methods Wistar albino rats after an exploration of the thoracolumbar paravertebral muscle tissue of the subjects, group I underwent a sham surgery, and groups II and III were implanted Ti alloy and SS alloy rods respectively. The CD4, CD8, CD25 (IL-2R) (lymphocyte and CD4 gate), CD4+CD8+ and CD4+CD25+Foxp3+ (Tregs), IL-4, IL-10, IL-6, IL-17A, TGF-β, TNF-α in the blood were analyzed. Results CD4, CD25 (IL-2R), CD4+CD8+ and Tregs levels were lower in the Group III compared to the sham and Group IIs. IL-6, IL-17A, TGF-β and TNF-α levels in the G III showed a significant increase on all days in comparison with the sham and Group II. IL-4 and IL-10 levels, were lower in the Group III than those in the Group II; and a significant decrease was observed in the IL-10 level. While there was a reduction in IL-6 and IL-17A levels in the Group II as opposed to the sham group. Conclusion As opposed to SS alloy, Ti alloy suppresses the development of inflammations by inhibiting proinflammatory response; strengthens the humoral immune system by intensifying the antibody-dependent immune response; triggers the development of immune tolerance by regulating the immune response; and activates the mechanism that prevents immune response-related damage from occurring.

Background and objectives: Ischemia&ndash, reperfusion (IR) caused by infrarenal abdominal aorta cross-clamping is an important factor in the development of ischemia&ndash, reperfusion injury in various distant organs. Materials and Methods: We investigated potential antioxidant/anti-inflammatory effects of thymosin beta 4 (T&beta, 4) in a rat model of abdominal aortic surgery-induced IR. T&beta, 4 (10 mg/kg, intravenous (i.v.)) was administered to rats with IR (90-min ischemia, 180-min reperfusion) at two different periods. One group received T&beta, 4 1 h before ischemia, and the other received 15 min before the reperfusion period. Results: Results were compared to control and non-T&beta, 4-treated rats with IR. Serum, bronchoalveolar lavage fluid and lung tissue levels of oxidant parameters were higher, while antioxidant levels were lower in the IR group compared to control. IR also increased inflammatory cytokine levels. T&beta, 4 reverted these parameters in both T&beta, 4-treated groups compared to the untreated IR group. Conclusions: Since there is no statistical difference between the prescribed results of both T&beta, 4-treated groups, our study demonstrates that T&beta, 4 reduced lung oxidative stress and inflammation following IR and prevented lung tissue injury regardless of timing of administration.

In this study, our aim is; if the studies will quide us in peripheral blood, for the changes in inflammatory cytokine levels we defined before DDH tissue. Twenty-six patients were suggestive of lumbar DDH were included in this study. Control subjects included 14 autopsy cases. From each patient, disc tissues and peripheral blood samples for plasma were collected during the surgery. For the controls, disc samples and blood for plasma by intracardiac puncture were obtained during autopsy. The Flow Cytometry was used to obtain the lymphocyte CD56 (NK). The Luminex was used to obtain IL-2, IL-4, IL-10, IL-12, IFN-gamma, in both plasma and disc tissues. The results were compared between the two groups. Comparing the two groups regarding plasma demonstrated that IL–2, IL–4, IL–12, IFN-gamma were significantly higher than in patients than those of the controls. Likewise, tissue levels of IL–2, IL–4, IL–10, IL–12, TNF-alpha, CD56 were found to be significantly higher in the patients. With respect to the comparison between the plasma disc samples in the patients, plasma showed significant higher levels of IL-2, IL-12 on the other hand IL-4 was found to be significantly higher in the disc samples. Findings suggest that only tissue samples responses in occurring but not blood samples. We don’t think our results in peripheral blood will guide us specifically in DDH.

Purpose: To compare the status of corneal endothelium and central corneal thickness within the first four postoperative years after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus. Materials and Methods: Thirty-nine eyes (Group A) which had PK and 44 eyes (Group B) which had DALK for the treatment of keratoconus were included in this retrospective study. The endothelial cell density (ECD), the mean endothelial cell area and the coefficient of variation of cell area were assessed with a non-contact specular microscope, and the central corneal thickness (CCT) was measured with an ultrasound pachymeter. Results: Mean ECD loss rate at two years was 36.24% in Group A and 18.12% in Group B (P

In the present study, gelatine scaffolds were manufactured by using modified 3D (3 Dimensional) printing machine and the effect of different parameters on scaffold structure were investigated. Such as; temperature, viscosity and surface tension of the gelatine solutions. The varying of gelatine solutions (1, 3, 5, 10, 15 and 20 wt.%) were prepared and characterized. It has been detected that, viscosity of those solutions were highly influenced by temperature and gelatine concentration. Specific CAD (Computer Assistant Design) model which has 67% porosity and original design were created via computer software. However, at high temperatures gelatine solutions caused like liquid but at the lower temperatures were observed the opposite behaviour. In addition to that, viscosity of 1,3,5 wt.% solutions were not enough to build a structure and 20 wt.% gelatine solution too hard to handle, because of the sudden viscosity changes with temperature. Even though, scaffold of the 20 wt.% gelatine solution printed hardly but it was observed the best printed solutions, which were 10 and 15 wt.% gelatine solutions. As a result, 3D printing of gelatine were found the values of the best temperature, viscosity, surface tension and gelatine concentration such as 25-35 °C, 36-163 cP, 46-59 mN/m and 15 wt.% gelatine concentration respectively.

The effects of lithium which is widely used for the treatment of bipolar disorder, on the specific and non-specific immune systems of rats have been investigated. Forty male rats were used. The rats were divided into control and four treatment groups, each contained 8 animals. While control group were fed with standard commercial pellet, 1, 1.4, 1.8 and 2.2 g/kg lithium was added to the diets of group-I, II, III and IV respectively for 30-days. Liver, spleen and kidney and body weight were weighed. Total white blood cell, granulocyte, lymphocyte and monocyte percentage, CD3, CD4, CD8, CD161 cells, CD4/CD8 ratio and serum lithium level were determined. The body weight decreased depending on the dose of the lithium. Treatments did not affect the relative weight of the organs studied. Granulocyte percentage was increased (P=0.026) significantly related to lithium dose. CD3 and CD4 cell ratios significantly decreased (P= 0.004 and P= 0.005 respectively) in rats fed with 2.2 g/kg lithium added diet. Despite of...

This study aims to evaluate how analgesia-sedation causes alterations of HLA-DR and cytokines (IL-10 and IL-6) in patients undergoing cerebral angiography for several cerebral vascular diseases.This study includes 41 males who underwent cerebral angiography. The study sample was divided into two: Group I had 7 patients who did not receive and group II had 34 patients who received analgesia-sedation before cerebral angiography. A venous blood sample was collected before and after cerebral angiography.Analgesia-sedation caused significant increase CD4+ and CD19 T lymphocytes (p0.001) but group I showed significant increase in CD40, CD154, and MHC-II levels (p0.001) after cerebral angiography.We suggest that the effects of fentanyl and midazolam on the immune response are the reflection of the effects by the monocyte, mHLA-DR expression. In the future, depending on the immunological status of the patients, different anesthetic applications including the new anesthetic agents that will be able to decrease immune system suppression will be required.

To compare the visual and refractive results in eyes with advanced keratoconus having deep anterior lamellar keratoplasty (DALK) with those having intrastromal corneal ring segment (ICRS) implantation.Dr. Lütfi Kırdar Kartal Training and Research Hospital, Istanbul, Turkey.Comparative case series.Records of advanced keratoconus patients with a clear central cornea and contact lens intolerance who had DALK or ICRS implantation were reviewed. Preoperatively and after 24 months, the uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and Orbscan II keratometry (K) readings in the 2 groups were comparable.The DALK group comprised 36 eyes and the ICRS group, 30 eyes. Both groups had a statistically significant increase in UDVA and CDVA from preoperatively to 24 months postoperatively (P.001). The DALK group had a statistically significantly greater improvement in UDVA and CDVA than the ICRS group 24 months postoperatively (P.001). The improvement in spherical equivalent (SE) refractive error, manifest sphere, and manifest cylinder was statistically significant in both groups (P.001). The mean reduction in SE and manifest cylinder were significantly greater in the DALK group (P.05). The postoperative reduction in the maximum and minimum K values was statistically significant in both groups (P.001); the mean reduction in K values was significantly greater in the DALK group (P.001).Although DALK provided greater improvement in visual acuity and refractive errors in advanced keratoconus cases, ICRS implantation may be an alternative treatment with satisfactory outcomes and less visual impact.

AIM Cerebral digital subtraction angiography (DSA) is an invasive procedure and may cause inflammatory responses in the body. This study aims to provide cytokine and lymphocyte profile in a population of patients underwent cerebral DSA. MATERIAL AND METHODS Forty-one male patients who admitted for cerebral DSA were included in this study. Patients were divided into two groups: Group I (n = 7) included patients who did not receive analgesia-sedation and group II (n = 34) received analgesia-sedation before procedure. For the molecules, a venous blood samples from every patient was collected before and after cerebral DSA. RESULTS Cytokine levels in group I showed a trend to increase in the majority of the molecules after the procedure except IL-1β. In group II, cytokines showed variable trend. When comparing the two groups regarding cytokine levels after cerebral DSA, IL-1β, IL-10, IL-12, and IFN-γ levels increased significantly in group II. Comparing the two groups with respect to lymphocytes after cerebral DSA showed that CD56 levels were significantly higher in group II and other parameters did not show significant differences. CONCLUSION It can be possible that delimitation of the action(s) of the cytokines affecting the secretion or activation of CD56 (natural killer) may avoid complications of inflammation after invasive procedures.

Aim Lumbar degenerative disc disease (DDD) is a common disease of advanced age characterized by progressive changes in the intervertebral disc and associated structures. There have been great efforts for years to explain its pathophysiological mechanism(s). This study aims to provide cytokine profile and in addition to the lymphocytes in a population of patients with lumbar DDD. Material and methods Twenty-six patients whose clinical and radiological features were suggestive of lumbar DDD that underwent surgery and 14 autopsy cases as control were included. Patient disc samples were obtained during surgery whilst disc materials were collected during autopsy procedures from the controls. Major cytokines and lymphocytes were studied by using the flow cytometry method. Results Significantly higher levels in disc samples in relation to IL-1β, IL-2, IL-4, IL-10, IL-12, TNF-α, CD8, CD56, CD19, and CD40 were found in the patients compared to the controls. Positive correlations were shown between CD3/CD4, CD25/CD3, CD25/CD4, CD19/CD4 but negative correlations were shown between CD19/CD3 and CD25/CD19 in both groups. Conclusion The findings suggest that both local inflammatory responses occur in lumbar DDD. Using specific cytokines either by local or systemic application may reverse the degenerative process.

Amaç: Penetran keratoplasti sonrası yüksek astigmatizmanın düzeltilmesinde wedge rezeksiyon yönteminin etkinliğini ve güvenirliliğini araştırmak. Gereç ve Yöntem: Penetran keratoplasti sütürleri alındıktan sonra korneadaki astigmatizması 6 dioptri ve üzerinde olan, bu nedenle wedge rezeksiyon yapılan saydam korneal greftlere sahip 24 hastanın 24 gözü çalışmaya alındı. Penetran keratoplastiden wedge rezeksiyona kadar geçen ortalama süre 23.7±14.5 aydı. Wedge rezeksiyon sonrası 1. ayda ve son kontrolde net ve vektöryel astigmatik değişimler, düzeltilmemiş ve düzeltilmiş görme keskinliği incelendi. Bulgular: Olgular en az 6 ay ve en fazla 32 ay olmak üzere ortalama 17.7±7.9 ay süre ile izlendi. Ameliyat öncesi ortalama 9.5±2.4 dioptri olan keratometrik astigmatizma, wedge rezeksiyon sonrası 1. ayda ortalama 3.9±2.0 dioptri ve son kontrolde 3.0±1.3 dioptri olarak bulundu. Girişim sonrası indüklenen vektöryel astigmatizma 1. ayda 10.6±4.8 dioptri ve son kontrolde 7.8±2.8 dioptri idi. Düzeltilmemiş görme keskinliği ameliyat öncesinde ortalama 1.17±0.23 logMAR iken wedge rezeksiyon sonrası 1. ayda 0.80±0.31 logMAR ve son kontrolde 0.74±0.30 logMAR idi. Düzeltilmiş görme keskinliği ameliyat öncesinde ortalama 0.35±0.15 logMAR iken ameliyat sonrası 1. ayda 0.26±0.20 logMAR ve son kontrolde 0.21±0.15 logMAR idi. Takip sırasında 2 olguda tedavi ile düzelen greft reddi izlendi. Sonuç: Penetran keratoplasti sonrası yüksek astigmatizmanın düzeltilmesinde wedge rezeksiyonun etkili ve güvenli bir yöntem olduğu gözlenmiştir. Ancak cerrahi sonrası görsel düzelme için belirli bir süreye ihtiyaç vardır., Purpose: To evaluate the efficacy and safety of wedge resection in the treatment of high astigmatism following penetrating keratoplasty (PK). Material and Methods: Twenty four eyes of 24 clear grafted patients who underwent corneal wedge resection for residual high astigmatism of 6.00 diopters (D) or greater after PK suture removal were included in this study. The average time interval between PK and wedge resection was 23.7±14.5 months. Absolute and vectorial reductions in astigmatism, uncorrected and best corrected visual acuities were measured at first month and at the last control visit after wedge resection. Results: The patients were followed 6 to 32 months and the mean follow-up time was 17.7±7.9 month. The mean preoperative keratometric astigmatism was 9.5±2.4 D. After wedge resection, the mean keratometric astigmatism was 3.9±2.0 D at first month and 3.0±1.3 D in the last control visit. Induced vectorial astigmatism following the procedure was 10.6±4.8 D at first month and 7.8 D±2.8 in the last control visit. Mean preoperative uncorrected visual acuity was 1.17±0.23 logMAR, while it was 0.80±0.31 logMAR at the first month and 0.74±0.30 logMAR in the last visit. Mean preoperative best corrected visual acuity was 0.35±0.15 logMAR, while it was 0.26±0.20 logMAR at first month and 0.21±0.15 logMAR in the last visit. During the follow-up, in 2 cases a graft rejection attack that was treated succesfully has occured. Conclusion: Corneal wedge resection is safe and effective procedure for residual high astigmatism after penetrating keratoplasty. However, a determined time is necessary after surgery for visual improvement.

Exosome release by viable cells is a feature of activated cell types, including tumors, fetal cells, and cells of the immune system. Exosomes critically regulate immune activation, by mediating activation-induced cell death. Fetal cells may mimic these events to selectively delete reactive lymphocytes. In this study the presence and composition of placenta-derived exosomes are demonstrated in the maternal circulation along with their consequences on T cell activation markers. For all pregnant patients, exosomes were isolated from sera obtained between 28 and 30 wk gestation. For pregnant women, subsequently delivering at term, circulating levels of placental exosomes were 1.8 times greater than those delivering preterm (p < 0.0001). Exosomes isolated from pregnancies subsequently delivering at term expressed significantly higher levels of biologically active components, including Fas ligand (FasL) and HLA-DR, than those from pregnancies delivering preterm. Standardizing for protein concentrations, exosomes from term-delivering pregnancies exhibited greater suppression of CD3-ζ and JAK3 than those delivering preterm. The suppression of CD3-ζ and JAK3 correlated with exosome expression levels of FasL (r2 = 0.92 and r2 = 0.938, respectively). Fractionation of exosomes from term-delivering pregnancies by continuously eluting electrophoresis indicated that intact 42kD FasL and an unidentified 24-kDa protein were associated with CD3-ζ suppression. Our results demonstrated that exosomes from pregnancies ultimately delivering at term are present at significantly greater concentrations than those from pregnancies delivering preterm; however, exosomes from term-delivering pregnancies also exhibit significantly greater suppression of CD3-ζ and JAK3.