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2.
Front Immunol ; 15: 1379622, 2024.
Article in English | MEDLINE | ID: mdl-38638433

ABSTRACT

Despite advances in cancer treatment, hepatocellular carcinoma (HCC), the most common form of liver cancer, remains a major public health problem worldwide. The immune microenvironment plays a critical role in regulating tumor progression and resistance to therapy, and in HCC, the tumor microenvironment (TME) is characterized by an abundance of immunosuppressive cells and signals that facilitate immune evasion and metastasis. Recently, anti-cancer immunotherapies, therapeutic interventions designed to modulate the immune system to recognize and eliminate cancer, have become an important cornerstone of cancer therapy. Immunotherapy has demonstrated the ability to improve survival and provide durable cancer control in certain groups of HCC patients, while reducing adverse side effects. These findings represent a significant step toward improving cancer treatment outcomes. As demonstrated in clinical trials, the administration of immune checkpoint inhibitors (ICIs), particularly in combination with anti-angiogenic agents and tyrosine kinase inhibitors, has prolonged survival in a subset of patients with HCC, providing an alternative for patients who progress on first-line therapy. In this review, we aimed to provide an overview of HCC and the role of the immune system in its development, and to summarize the findings of clinical trials involving ICIs, either as monotherapies or in combination with other agents in the treatment of the disease. Challenges and considerations regarding the administration of ICIs in the treatment of HCC are also outlined.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Immune Checkpoint Inhibitors/therapeutic use , Liver Neoplasms/drug therapy , Immunotherapy , Angiogenesis Inhibitors , Tumor Microenvironment
3.
Surg Oncol ; 52: 102037, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38290327

ABSTRACT

INTRODUCTION: Following major developments in cancer immunotherapy, treatments targeting immune checkpoint proteins (ICP) gained interest in breast cancer, though studies mostly focus on patients with metastatic disease as well as patients nonresponsive to the conventional treatments. Herein, we aimed to investigate the levels of ICP in tumor stroma and tumor infiltrating lymphocytes, and tumor tissue prior to neoadjuvant chemotherapy administration to evaluate the relationship between ICP levels, clinicopathological parameters, and NAC response. MATERIALS AND METHODS: This study was conducted with 51 patients where PD-1, PD-L1, CTLA-4, TIM-3, CD24 and CD44 levels were investigated in CD45+ cells while CD326, CD24, CD44 and PD-L1 protein expression levels were investigated in CD45- population. In addition, CD44 and CD24 levels were evaluated in the tumor stroma. TIL levels were investigated according to the TILS Working Group. Treatment responses after NAC were evaluated according to the MD Anderson RCB score. RESULTS: Our results revealed positive correlation between CTLA-4 and CD44 expression in cases with high TIL levels as well as TIL levels and CTLA-4 expression in cases with partial response. Similarly, positive correlation was detected between TIM3 and PD-L1 levels in cases with good response. In addition, a negative correlation between TILs after NAC and PD-1/PD-L1 expression in lymphocytes in cases with partial complete response. CONCLUSIONS: Our study provides preliminary data about the correlation between ICP and clinicopathological status and NAC response in breast cancer, in addition to underlining the requirement for further research to determine their potential as therapeutic targets.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/pathology , Immune Checkpoint Proteins/therapeutic use , B7-H1 Antigen/metabolism , CTLA-4 Antigen/therapeutic use , Neoadjuvant Therapy , Programmed Cell Death 1 Receptor/therapeutic use , Prognosis
4.
Front Neurosci ; 17: 1277399, 2023.
Article in English | MEDLINE | ID: mdl-38105925

ABSTRACT

This review aims to summarize the latest evidence about the role of innate and adaptive immunity in Amyotrophic Lateral Sclerosis (ALS). ALS is a devastating neurodegenerative disease affecting upper and lower motor neurons, which involves essential cells of the immune system that play a basic role in innate or adaptive immunity, that can be neurotoxic or neuroprotective for neurons. However, distinguishing between the sole neurotoxic or neuroprotective function of certain cells such as astrocytes can be challenging due to intricate nature of these cells, the complexity of the microenvironment and the contextual factors. In this review, in regard to innate immunity we focus on the involvement of monocytes/macrophages, microglia, the complement, NK cells, neutrophils, mast cells, and astrocytes, while regarding adaptive immunity, in addition to humoral immunity the most important features and roles of T and B cells are highlighted, specifically different subsets of CD4+ as well as CD8+ T cells. The role of autoantibodies and cytokines is also discussed in distinct sections of this review.

6.
Front Immunol ; 14: 1108200, 2023.
Article in English | MEDLINE | ID: mdl-36742324

ABSTRACT

Acute myeloid leukemia (AML) arises from the cells of myeloid lineage and is the most frequent leukemia type in adulthood accounting for about 80% of all cases. The most common treatment strategy for the treatment of AML includes chemotherapy, in rare cases radiotherapy and stem cell and bone marrow transplantation are considered. Immune checkpoint proteins involve in the negative regulation of immune cells, leading to an escape from immune surveillance, in turn, causing failure of tumor cell elimination. Immune checkpoint inhibitors (ICIs) target the negative regulation of the immune cells and support the immune system in terms of anti-tumor immunity. Bone marrow microenvironment (BMM) bears various blood cell lineages and the interactions between these lineages and the noncellular components of BMM are considered important for AML development and progression. Administration of ICIs for the AML treatment may be a promising option by regulating BMM. In this review, we summarize the current treatment options in AML treatment and discuss the possible application of ICIs in AML treatment from the perspective of the regulation of BMM.


Subject(s)
Bone Marrow , Leukemia, Myeloid, Acute , Humans , Bone Marrow/metabolism , Immune Checkpoint Inhibitors/therapeutic use , Immune Checkpoint Inhibitors/metabolism , Leukemia, Myeloid, Acute/therapy , Bone Marrow Transplantation , Neoplastic Stem Cells , Tumor Microenvironment
7.
Balkan Med J ; 40(2): 117-123, 2023 03 08.
Article in English | MEDLINE | ID: mdl-36748249

ABSTRACT

Background: Various studies have reported the effects of testosterone on different cell types, yet bone marrow-derived mesenchymal stem cells' cellular responses to testosterone remain unknown. Aims: To investigate the effects of testosterone propionate, an oil-soluble short-acting form of testosterone, on human bone marrow-derived mesenchymal stem cells' proliferation and viability after 24 hours of incubation. We also investigated the impact of testosterone propionate on bone marrow-derived mesenchymal stem cell's polarization and cytotoxicity on K562 leukemia cell line. Study Design: In vitro study. Methods: We expanded commercially available bone marrow derived mesenchymal stem cells in vitro and treated them with testosterone propionate at concentrations ranging from 10-6-10-10 M for 24 hours. Ideal concentration was determined by evaluating cellular viability and proliferation with Annexin V/Propidium Iodide assay and carboxyfluorescein succinimidyl ester staining. The characteristic features of bone marrow-derived mesenchymal stem cells were evaluated by immunophenotyping and investigating their differentiation capacities. Bone marrow-derived mesenchymal stem cells' cytotoxic properties upon testosterone propionate treatment were determined by co-culturing the cells with K562 cells and with confocal imaging investigating polarization. Results: Testosterone propionate promoted proliferation and maintained the viability of bone marrow-derived mesenchymal stem at 10-8 M concentration. Further evaluations were conducted with the determined dose. The results showed that, apart from promoting mesenchymal stem cells' polarization and increasing their cytotoxicity on K562 cells, testosterone propionate did not alter differentiation capacities of bone marrow-derived mesenchymal stem cells and certain cell surface markers, but led to a significant increase in HLA-DR expression. Conclusion: The findings reveal that testosterone propionate promotes the proliferation and survival of bone marrow-derived mesenchymal stem cells in a dose-dependent manner without hampering their differentiation capacities, induces their polarization to the pro-inflammatory phenotype, and increases their cytotoxicity on the K562 cell line.


Subject(s)
Mesenchymal Stem Cells , Neoplasms , Testosterone Propionate , Humans , Testosterone Propionate/metabolism , Testosterone Propionate/pharmacology , Mesenchymal Stem Cells/metabolism , Cell Differentiation/physiology , Neoplasms/metabolism , Cell Proliferation
8.
Phytochemistry ; 208: 113590, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36696936

ABSTRACT

Cytotoxic activity-guided isolation studies on the underground parts of Valeriana sisymbriifolia Vahl. led to the isolation of 12 secondary metabolites including two undescribed iridoids, sisymbriifolivaltrate and sisymbriifolioside, and two unreported sesquiterpene lactones, sisymbriifolins A and B. Chemical structures of the isolates were established by extensive 1D and 2D NMR analyses as well as HR-ESI-MS. The in vitro cytotoxic activities of the extract, sub-fractions and isolates on lung (A549), breast (MCF7), gastric (HGC27) and prostate (PC3) cancer cell lines were evaluated by MTS assay. Sisymbriifolivaltrate, didrovaltrate, valtrate, 7-homovaltrate and 1-α-acevaltrate exhibited promising cytotoxic activity on MCF7 cell line with IC50 values ranging from 2.5 to 12.3 µM, while valtrate demonstrated the best cytotoxicity against A549 cells with the IC50 value of 7.5 µM. Valtrate and 7-homovaltrate were found to exert noteworthy cytotoxicity towards HGC27 cell line (IC50 values: 2.3 and 3.7 µM, respectively), whereas valtrate, 7-homovaltrate and 1-α-acevaltrate (IC50 values: 2.3-9.7 µM) were found to be potent cytotoxic against PC3 cells. Among the tested compounds, particularly valepotriate-type iridoids were found to be the main cytotoxic principles of V. sisymbriifolia.


Subject(s)
Antineoplastic Agents , Valerian , Animals , Valerian/chemistry , Iridoids/chemistry
9.
Chem Biodivers ; 19(10): e202200659, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36111652

ABSTRACT

The aim of this study was to isolate the cytotoxic compounds from V. alliariifolia via activity-guided isolation and to determine the mechanism of actions of the most potent ones. The crude EtOH extract as well as CHCl3 and AcOEt subextracts demonstrated remarkable cytotoxic activities against A549, MCF7, HGC27 and PC3 cancer cells. Sequential chromatographic separations on active subextracts yielded 14 secondary metabolites, including 11 iridoids (1-11) most of which belong to non-glycosidic ester iridoids, two phenylpropanoids (12 and 13) and one lignan (14). The chemical structures of purified compounds were elucidated by NMR and MS analysis. Among the isolates, 7-deisovaleroylvaltrate (3) was isolated for the first time as a natural product. According to the cytotoxic assay compounds, 2, 4-6 and 8 were found to be the potent cytotoxic compounds (IC50 <10 µM) against at least one of the tested cancer cell lines. Thus, 2, 4-6 and 8 were investigated for their effects on apoptotic, necrotic and autophagic pathways as well as cell cycle progression. They exerted anticancer activities by inducing different cell death mechanisms depending on the cancer cells. The results demonstrated that 2, 4-6 and 8 could be potential anticancer drug leads that deserve further in vivo and clinical studies on the way to discover novel natural compounds with anticancer properties.


Subject(s)
Antineoplastic Agents , Lignans , Valerian , Valerian/chemistry , Iridoids/pharmacology , Iridoids/chemistry , Esters , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Death , Plant Extracts/pharmacology , Plant Extracts/chemistry
10.
ACS Appl Bio Mater ; 5(8): 3936-3950, 2022 08 15.
Article in English | MEDLINE | ID: mdl-35802827

ABSTRACT

Colorectal cancer ranks as the third most lethal cancer worldwide, resulting in over 1 million cases and 900 000 deaths per year. According to population-based studies, administration of long-term non-steroidal anti-inflammatory drugs (NSAIDs) was proven to reduce the risk of a subject developing colorectal cancer. In the present study, the anti-cancer activity of two different NSAIDs, sulindac- (Pc-1) or diclofenac-substituted (Pc-2) asymmetric silicon phthalocyanine derivatives, was evaluated in four different colorectal cancer cell lines bearing various carcinogenic mutations. In this context, the IC50 values of each compound after 24 and 48 h were determined on HCT116, SW480, LoVo, and HT29 cell lines, and the effects of the compounds on programmed cell death pathways apoptosis and autophagy, their impact on cell cycle progression, and the effect of NSAID moieties they bear on COX-1 and COX-2 proteins were analyzed. In addition, the photophysical and photochemical properties of a synthesized Pc derivative bearing axial diclofenac and triethylene glycol groups (Pc-2) have been investigated, and the compound has been characterized by using different analytical techniques. Our results indicated that both compounds inhibit COX protein expression levels, activate apoptosis in all cell lines, and lead to cell cycle arrest in the G2/M phase, depending on the COX expression profiles of the cell lines, indicating that NSAIDs can be coupled with Pc's to achieve increased anti-cancer activity, especially on cancer cells known to have high COX activity.


Subject(s)
Colorectal Neoplasms , Cyclooxygenase Inhibitors , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Colorectal Neoplasms/drug therapy , Cyclooxygenase Inhibitors/pharmacology , Diclofenac/pharmacology , HT29 Cells , Humans , Indoles , Organosilicon Compounds , Silicon/therapeutic use
11.
Front Oncol ; 12: 789728, 2022.
Article in English | MEDLINE | ID: mdl-35155232

ABSTRACT

The development of immune checkpoint inhibitors, the monoclonal antibodies that modulate the interaction between immune checkpoint molecules or their ligands on the immune cells or tumor tissue has revolutionized cancer treatment. While there are various studies proving their efficacy in hematological malignancies, there is also a body of accumulating evidence indicating that immune checkpoint inhibitors' clinical benefits are limited in such diseases. In addition, due to their regulatory nature that balances the immune responses, blockade of immune checkpoints may lead to toxic side effects and autoimmune responses, and even primary or acquired resistance mechanisms may restrict their success. Thus, the need for laboratory biomarkers to identify and monitor patient populations who are more likely respond to this type of therapy and the management of side effects seem critical. However, guidelines regarding the use of immune checkpoint inhibitors in hematological cancers and during follow-up are limited while there is no consensus on the laboratory parameters to be investigated for safety and efficacy of the treatment. This review aims to provide an insight into recent information on predictive and prognostic value of biomarkers and laboratory tests for the clinical follow up of hematological malignancies, with an emphasis on leukemia.

12.
Turk Gogus Kalp Damar Cerrahisi Derg ; 30(4): 611-621, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36605322

ABSTRACT

Background: This study aims to evaluate humoral immune system response by measuring copy numbers of kappa-deleting recombination excision circles (KREC) gene segment from B lymphocytes in patients with lung transplantation. Methods: Between September 2015 and November 2016, a total of 11 patients (8 males, 3 females; mean age: 45.4±12.0 years; range, 23 to 59 years) who underwent lung transplantation with different primary indications were included. The copy numbers of KREC gene segment were quantified using real-time polymerase chain reaction method in peripheral blood samples collected pre- and post-transplantation. The samples of the patients were compared with the KREC l evels i n deoxyribonucleic acid extracted from blood samples of healthy children. Results: There was no significant change in KREC levels between pre- and post-operation (p=0.594 and p=0.657), although the median values indicated that the highest increase in the KREC levels (7x105- 12x105; 85-170) was on Day 7 of transplantation. There was a positive correlation between the KREC levels (mL in blood) and lymphocytes at 24 h after transplantation (p=0.043) and between KREC copies per 106 of blood and age on Day 7. Conclusion: Our preliminary results suggest that KREC l evels a s an indicator of B lymphocyte production are elevated after lung transplantation. A prognostic algorithm by tracking B cell kinetics after post-transplantation for long-term follow-up can be developed following the confirmation of these preliminary results with more patient samples.

13.
J Obstet Gynaecol ; 42(1): 133-138, 2022 Jan.
Article in English | MEDLINE | ID: mdl-33908815

ABSTRACT

The aim was to compare granulosa cell's (GCs) apoptosis rate with (group A) or without (group B) luteinising hormone (LH) supplementation in poor ovarian responders (PORs) during controlled ovarian stimulation (COS). After oocyte retrieval, the follicular fluid was analysed by cytoflowmetry. Primary outcomes were GCs apoptosis rate in terms of viability, early apoptosis, late apoptosis and necrosis. Secondary outcome was clinical pregnancy rate. The viability was 96.7{IQR: 8} and 83.5{IQR: 20} for groups A and B, respectively (p < .001). Late apoptosis rates were significantly lower in group A (median 1.5, {IQR: 3.1}) than group B (median 9.5, {IQR: 20.6}) (p < .001). Median early apoptosis rates were 1.4 {IQR: 2.9} and 5.2 {IQR: 6.5} for group A and B respectively (p = .04). No significant difference was observed in the clinical pregnancy rate. Although LH seems necessary in PORs to decrease late granulosa apoptosis rates, this does not improve clinical pregnancy rates.IMPACT STATEMENTWhat is already known on this subject? LH supplementation during COS has long been an issue in PORs to overcome the rFSH responsiveness due to the LH polymorphism. LH receptors have also been on GCs and their expression increases in preovulatory follicles. GCs apoptosis rates may show the oocyte quality and reproductive potential of oocyte retrieved and the requirement for LH supplementation.What do the results of this study add? The present study shows that LH supplementation during COS for PORs promotes the GC viability and reduces early/late apoptosis rates. Similarly, the number of MII oocytes was significantly higher in the LH regimen group. However, there was no significant difference in terms of clinical pregnancy rates.What are the implications of these findings for clinical practice and/or further research? The oocyte quality parameters such as higher GC viability and lower GC early/late apoptosis rates verify the LH supplementation in PORs during COS. However, the limited size of this study requires further multi-centre research in a larger cohort of patients. Results obtained with a sensitive and validated method will help clinicians to make better decisions in patient care.


Subject(s)
Apoptosis/drug effects , Cell Survival/drug effects , Follicular Fluid/cytology , Granulosa Cells/drug effects , Luteinizing Hormone/administration & dosage , Adult , Female , Humans , Oocyte Retrieval/methods , Ovulation Induction/methods , Pregnancy , Pregnancy Rate , Prospective Studies
14.
J Tissue Eng Regen Med ; 14(12): 1815-1826, 2020 12.
Article in English | MEDLINE | ID: mdl-33010108

ABSTRACT

Regeneration of nerve tissue is a challenging issue in regenerative medicine. Especially, the peripheral nerve defects related to the accidents are one of the leading health problems. For large degeneration of peripheral nerve, nerve grafts are used in order to obtain a connection. These grafts should be biodegradable to prevent second surgical intervention. In order to make more effective nerve tissue engineering materials, nanotechnological improvements were used. Especially, the addition of electrically conductive and biocompatible metallic particles and carbon structures has essential roles in the stimulation of nerves. However, the metabolizing of these structures remains to wonder because of their nondegradable nature. In this study, biodegradable and conductive nerve tissue engineering materials containing zero-valent iron (Fe) nanoparticles were developed and investigated under in vitro conditions. By using electrospinning technique, fibrous mats composed of electrospun poly(ε-caprolactone) (PCL) nanofibers and Fe nanoparticles were obtained. Both electrical conductivity and mechanical properties increased compared with control group that does not contain nanoparticles. Conductivity of PCL/Fe5 and PCL/Fe10 increased to 0.0041 and 0.0152 from 0.0013 Scm-1 , respectively. Cytotoxicity results indicated toxicity for composite mat containing 20% Fe nanoparticles (PCL/Fe20). SH-SY5Y cells were grown on PCL/Fe10 best, which contains 10% Fe nanoparticles. Beta III tubulin staining of dorsal root ganglion neurons seeded on mats revealed higher cell number on PCL/Fe10. This study demonstrated the impact of zero-valent Fe nanoparticles on nerve regeneration. The results showed the efficacy of the conductive nanoparticles, and the amount in the composition has essential roles in the promotion of the neurites.


Subject(s)
Iron/chemistry , Metal Nanoparticles/chemistry , Nanofibers/chemistry , Nerve Tissue/physiology , Tissue Engineering , Tissue Scaffolds/chemistry , Animals , Astrocytes/cytology , Cell Adhesion , Cell Death , Electric Conductivity , Ganglia, Spinal/metabolism , Humans , Metal Nanoparticles/ultrastructure , Mice , Mice, Inbred BALB C , NIH 3T3 Cells , Nanofibers/ultrastructure , Polyesters/chemistry , Tensile Strength
15.
ACS Omega ; 5(40): 25854-25867, 2020 Oct 13.
Article in English | MEDLINE | ID: mdl-33073111

ABSTRACT

In this study, we synthesized and characterized a silicon phthalocyanine substituted with 3-hydroxypyridin-2-thione (SiPc-HDACi), designed to be a chemophotodynamic therapy agent acting as a histone deacetylase inhibitor, and we determined its photophysical, photochemical, and photobiological properties. Next, we evaluated its anticancer efficacy on MCF-7, double positive and MDA-MB-231, triple negative breast cancer cell lines, as well as on a healthy human endothelial cell line (HUVEC). Our results indicate that SiPc-HDACi can target nucleoli of cells, effectively inducing apoptosis while promoting cell cycle arrest thanks to its high singlet oxygen yield and its histone deacetylase downregulating properties, suggesting a powerful anticancer effect on breast cancer in vitro. Our further studies will be conducted with primary breast cancer cell culture to give a better insight into the anticancer mechanism of the compound.

16.
Front Immunol ; 11: 2169, 2020.
Article in English | MEDLINE | ID: mdl-33042129

ABSTRACT

Many anticancer therapies such as antibody-based therapies, cellular therapeutics (e.g., genetically modified cells, regulators of cytokine signaling, and signal transduction), and other biologically tailored interventions strongly influence the immune system and require tools for research, diagnosis, and monitoring. In flow cytometry, in vitro diagnostic (IVD) test kits that have been compiled and validated by the manufacturer are not available for all requirements. Laboratories are therefore usually dependent on modifying commercially available assays or, most often, developing them to meet clinical needs. However, both variants must then undergo full validation to fulfill the IVD regulatory requirements. Flow cytometric immunophenotyping is a multiparametric analysis of parameters, some of which have to be repeatedly adjusted; that must be considered when developing specific antibody panels. Careful adjustments of general rules are required to meet legal and regulatory requirements in the analysis of these assays. Here, we describe the relevant regulatory framework for flow cytometry-based assays and describe methods for the introduction of new antibody combinations into routine work including development of performance specifications, validation, and statistical methodology for design and analysis of the experiments. The aim is to increase reliability, efficiency, and auditability after the introduction of in-house-developed flow cytometry assays.


Subject(s)
Accreditation/legislation & jurisprudence , Flow Cytometry/methods , Government Regulation , Lymphocytes/immunology , Neoplasms/therapy , Biomarkers/metabolism , Clinical Laboratory Techniques , Humans , Immunophenotyping , Neoplasms/immunology , Practice Guidelines as Topic , Quality Control , Reproducibility of Results
17.
Carbohydr Polym ; 219: 87-94, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31151549

ABSTRACT

Oxidized cellulose is the most used hemostatic materials in clinical applications. In addition to its perfect hemostatic efficiency, it is degradable under in vivo conditions and supremely prevents bacterial growth. On the other hand, one of the drawbacks of the oxidized cellulose is cytotoxicity due to the strongly acidic nature during degradation. There is a number of commercially available oxidized cellulose products which are derived from regenerated and non-regenerated cellulose. On the other hand, the effect of oxidation degree and structure (regenerated or non-regenerated) on product efficiency is undetermined. Moreover, oxidation degree which is primary factor for both bactericidal and hemostatic efficiency is also crucial for assessment of the product. In this study, oxidized cellulose versus oxidized regenerated cellulose microparticles with various oxidation degree was produced and characterized. Comparative studies were conducted in terms of bactericidal and hemostatic efficiencies in addition to cytotoxicity. The results could be a reference for the optimized oxidized cellulose product for the hemostatic applications.


Subject(s)
Anti-Bacterial Agents , Cellulose, Oxidized/pharmacology , Cellulose, Oxidized/toxicity , Hemolysis , Hemostasis/drug effects , Staphylococcus aureus/drug effects , 3T3 Cells , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Cellulose, Oxidized/chemistry , Humans , Mice , Oxidation-Reduction
18.
Mater Sci Eng C Mater Biol Appl ; 99: 1141-1152, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30889648

ABSTRACT

Hernia surgeries are at the top of the general surgery operations. However, visceral adhesion, which is one of the worst complications of these operations, is still a major problem. One of the most preferred methods to prevent adhesion is the use of biomaterials. Polypropylene (PP) mesh is frequently preferred product in clinical applications owing to its mechanically robust structure against deformation within the body. However, PP meshes do not have anti-adhesive properties. Oxidized regenerated cellulose (ORC), on the other hand, is one of the most preferred products in preventing the adhesion in clinical use. ORC is not easily processable due to solubility limitations; and it must be used externally. In this study, for the first time, we designed a composite mesh structure with ORC and produced an antibacterial and anti-adhesive double-sided mesh by electro-spinning ORC micro-particles with poly(ε­caprolactone) (PCL) on PP mesh to form a composite structure. We conducted in vitro cell culture studies to determine bio-compatibility performances. We evaluated the anti-adhesion and comprehensive bio-compatibility studies through in vivo experiments. The results revealed that ORC presence and optimization of ORC degradation by coating with PCL play an important role in adhesion prevention and introduced a product prototype with efficient anti-adhesion properties.


Subject(s)
Cellulose, Oxidized/pharmacology , Hernia/pathology , Polypropylenes/pharmacology , Surgical Mesh , Tissue Adhesions/prevention & control , Animals , Herniorrhaphy , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Hydrogen-Ion Concentration , Implants, Experimental , Male , Rats, Sprague-Dawley , Tensile Strength , Tissue Adhesions/pathology
19.
Carbohydr Polym ; 200: 624-632, 2018 Nov 15.
Article in English | MEDLINE | ID: mdl-30177208

ABSTRACT

Effective hemostatic materials are of utmost importance for preventing bleeding in emergencies and critical injuries. Combining biodegradability, good hemostatic properties and biocompatibility, gelatin is one of the most reliable materials clinically used for preventing internal bleeding in surgeries and for stopping external hemorrhage. Cross-linking is a useful method for enhancing the absorption capacity of gelatin and for controlling the degradation process. Existing and commonly used aldehyde-containing cross-linking agents lack reliability with respect to the control of hemostatic effect, solubility and toxicity. In this study; gelatin was cross-linked with sodium oxidized regenerated cellulose (NaORC) to produce hemostatic microparticles. The NaORC was used at different ratios; and the studies on hemostatic efficiency and cytotoxicity under in vitro conditions demonstrated rapid arrest of bleeding alongside biocompatibility. These microparticles employing NaORC as a cross-linking agent for the first time demonstrated a unique structure for stopping bleeding with biocompatibility, and opened the way for different forms of cross-linked structures to be used in other biomaterials applications.

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