In Vivo Evaluation of Zinc-Containing Nanostructured Carbonated Hydroxyapatite

The hydroxyapatite (HA) is a biocompatible and bioactive biomaterial used as bone substitute, however, the high crystallinity of HA and consequently its low solubility may be a limitation for its clinical use. In order to improve the biosorption of HA, the partial substitutions in the chemical structure and doping with small amounts of impurities have been study. The objective of this study was to evaluate the biocompatibility of 3% Zinc-containing nanostructured carbonated hydroxyapatite (ZncHA) compared with the carbonated hydroxyapatite (cHA), both synthesized at 37°C and non-sintered, using as control the stoichiometric HA microspheres in subcutaneous of mice. The X-ray Diffraction (XRD) and Vibrational Spectroscopy in Infra Red Fourier Transform (FTIR) were used to characterize the biomaterials. In vivo test was performed in BALB/c mice by implanting of HA, cHA and ZncHA spheres in the subcutaneous tissue for 1, and 9 weeks (n=5). The negative control consisted in incision without material implantation (Sham group). The samples were histological processed to descriptive analysis of biological effect. The microscopic analysis showed a similar granulation reaction between groups at the first experimental period. In 9 weeks there was a time dependent biosorption of cHA compared with other groups. In conclusion, the biomaterials tested were biocompatible and cHA group showed a significant biosorption in comparison with HA and ZncHA groups. The doping of zinc did not influence the biocompatibility of biomaterial, however, change the biosorption response

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In Vivo Evaluation of Strontium-Containing Nanostructured Carbonated Hydroxyapatite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.696.212 ◽

2016 ◽

Vol 696 ◽

pp. 212-222

Author(s):

Gabriel Maia Kammer ◽

Suelen Cristina Sartoretto ◽

Rodrigo Resende ◽

Marcelo Uzeda ◽

Jhonathan Raphael Nascimento ◽

...

Keyword(s):

Sham Group ◽

Subcutaneous Tissue ◽

Biological Response ◽

Experimental Period ◽

Giant Cells ◽

Control Group ◽

X Ray Diffraction ◽

Carbonated Hydroxyapatite ◽

X Ray

Bone tissue is a composite material that has hydroxyapatite (HA) as its main inorganic phase component. The biological apatites have low crystallinity and contain cationic and anionic substitutions in their structure, which differ from the available synthetic ceramics. The purpose of this study is to evaluate the biocompatibility of nanostructured carbonated hydroxyapatite microspheres containing 5 wt% strontium (SrcHA) compared with the biocompatibility of carbonated hydroxyapatite (cHA), both synthesized at 37°C and non-sintered, used to control stoichiometric HA microspheres in subcutaneous tissue of mice. The biomaterials (BM) were characterized using X-ray Diffraction (XRD), Vibrational Spectroscopy in an Infrared Fourier Transform (VSIRFT) and Scanning Electron Microscopy (SEM). Forty five balb-C mice were randomly divided into four groups of 15 animals each: SrcHA, cHA, HA, and without material implantation (Sham group). All samples were histologically processed for descriptive evaluation of the biological effect. At each experimental period (1, 3 and 9 weeks), there was a higher biosorption of the tested biomaterials observed in contrast with the HA. The cHA group was the only group completely phagocytosed by macrophages and giant cells after 9 weeks. All biomaterials proved to be biocompatible, and the cHA and SrcHA 3% groups exhibited a faster bioabsorption in comparison with the control group. The doping of strontium did not cause a greater biological response after the 3 experimental periods.

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Comparative In Vivo Study of Biocompatibility of Apatites Incorporated with 1% Zinc or Lead Ions versus Stoichiometric Hydroxyapatite

Journal of Biomimetics Biomaterials and Tissue Engineering ◽

10.4028/www.scientific.net/jbbte.19.109 ◽

2014 ◽

Vol 19 ◽

pp. 109-120 ◽

Cited By ~ 1

Author(s):

Bruno Giorno ◽

Igor Iuco Castro-Silva ◽

Alexandre Malta Rossi ◽

José Mauro Granjeiro

Keyword(s):

Inflammatory Response ◽

Bone Repair ◽

Divalent Cations ◽

Subcutaneous Tissue ◽

Microscopic Analysis ◽

Lead Toxicity ◽

Positive Control ◽

Physico Chemical ◽

Histological Processing

Hydroxyapatite is the main ceramic material that has being used in bone repair, although its physico-chemical and in vivo behavior should be better understood. A method to improve the biocompatibility of HA is the substitution of calcium with divalent cations which enhance mechanic resistance and can modulate inflammatory response against implanted material. In this study we analyzed the biocompatibility of HA doped with one per cent of Zn2+ or Pb2+. The first one has being described as an inflammation modulator and the second would be a model for chronic toxicity assay. Biocompatibility of the both materials was studied in vivo following the ISO 10993-6 standard. HA cylinders (ZnHA, PbHA and stoichiometric HA as positive control) were implanted into subcutaneous tissue of 45 Balb-c mice and after 1, 3 and 9 weeks the animals were euthanized (5 for each experimental condition). Necropsies of the skin containing reactional tissue were removed, fixed in 10% formaldehyde and followed the histological processing for paraffin embedding and staining with Hematoxylin-Eosine and Picrosirius red. Microscopic analysis showed for all groups moderate inflammatory response, decreasing throughout the experimental periods, with ZnHA group showing more intense response. Similar presence of macrophages, fibrosis and angiogenesis were observed among the groups. Thereby, we can conclude that ZnHA and PbHA are biocompatible and not bioresorbable, being the ZnHA potentially indicated as bone graft. Detailed studies are required to better understand the role of PbHA as chronic model for lead toxicity.

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Reconstruction of Kidney-Like Tissue Using ECM Gel and Rat Embryonic Kidney Fragments

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.342-343.1 ◽

2007 ◽

Vol 342-343 ◽

pp. 1-4

Author(s):

Ying Jian Zhu ◽

Wei Liu ◽

Wen Jie Zhang ◽

Guang Dong Zhou ◽

Guo Hua Liu ◽

...

Keyword(s):

Tissue Engineering ◽

Subcutaneous Tissue ◽

Kidney Tissue ◽

Polyglycolic Acid ◽

Negative Control ◽

Engineering Technique ◽

Solid Foundation ◽

Ecm Gel ◽

Further Development

Organ engineering remains a challenge to researchers. We tried to reconstruct kidney-like tissue using tissue engineering technique. Kidney fragments were isolated from rat E16 embryonic kidneys and seeded on either ECM gel or on polyglycolic acid (PGA) fibers, then implanted in vivo into the subcutaneous tissue of nude mice for 2 and 3 weeks, respectively. As a negative control, ECM alone was implanted. Results showed that kidney like tissue could be formed in ECMfragment constructs after 2 or 3 weeks of implantation, including the formation of glomeruli, tubules and collecting ducts. In addition, these structures seemed more mature in 3 weeks specimens than that of 2 weeks. Further development of this model may lay a solid foundation for kidney tissue engineering.

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Bacterial recovery using sonication versus swabbing of titanium and stainless steel implants inoculated with Staphylococcus pseudintermedius or Pseudomonas aeruginosa

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-17-02-0031 ◽

2017 ◽

Vol 30 (05) ◽

pp. 346-350 ◽

Cited By ~ 1

Author(s):

J. Case ◽

James Wellehan ◽

Mauricio Dujowich ◽

Thomas Keeshen

Keyword(s):

Pseudomonas Aeruginosa ◽

Stainless Steel ◽

Sham Group ◽

Group Versus ◽

Surgical Site Infections ◽

Negative Control ◽

Staphylococcus Pseudintermedius ◽

Bacterial Colony

SummaryObjective: To evaluate the use of sonication to improve recovery of bacteria from metal discs infected with bacteria commonly associated with implant infections in veterinary medicine.Methods: In vitro study in which sterile titanium (Ti6Al4V) and stainless steel (AIS1316-L) discs were incubated with either Staphylococcus pseudintermedius or Pseudomonas aeruginosa for 24 hours. The following three groups were compared: 1) the sonication group involved immersing the discs in sterile saline and sonicating for five minutes; 2) the sham group was considered a negative control in which the discs were immersed in saline for five minutes without sonication; and 3) the swab group involved systematically swabbing the implant with a sterile culturette. All samples were plated on blood agar and incubated for 24 hours. Colonies were then counted and compared.Results: For both species of bacteria, there was a significant increase in bacterial colonies isolated using sonication compared to the other two study groups (p = 0.0001). No differences in bacterial growth were found between the two types of metal implants. There was a significant increase in bacterial colony counts for S. pseudintermedius when comparing the swab group versus the sham group, but this was not significant for P. aeruginosa.Clinical significance: Sonication significantly improves recovery of bacteria commonly associated with veterinary implant-associated surgical site infections compared to swabbing of implants in vitro. A prospective clinical evaluation is indicated to determine the in vivo efficacy of sonication in veterinary patients.

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Evaluation of the In Vivo Biocompatibility of Amorphous Calcium Phosphate-Containing Metals

Journal of Functional Biomaterials ◽

10.3390/jfb11020045 ◽

2020 ◽

Vol 11 (2) ◽

pp. 45

Author(s):

Pio Moerbeck-Filho ◽

Suelen C. Sartoretto ◽

Marcelo J. Uzeda ◽

Maurício Barreto ◽

Alena Medrado ◽

...

Keyword(s):

Calcium Phosphate ◽

Amorphous Calcium Phosphate ◽

Subcutaneous Tissue ◽

Absorption Spectrometry ◽

Synthesis Temperature ◽

Carbonate Group ◽

Carbonated Hydroxyapatite ◽

Biological Apatite ◽

Semiquantitative Evaluation

Among the biomaterials based on calcium phosphate, hydroxyapatite has been widely used due to its biocompatibility and osteoconduction. The substitution of the phosphate group by the carbonate group associated with the absence of heat treatment and low synthesis temperature leads to the formation of carbonated hydroxyapatite (CHA). The association of CHA with other metals (strontium, zinc, magnesium, iron, and manganese) produces amorphous calcium phosphate-containing metals (ACPMetals), which can optimize their properties and mimic biological apatite. This study aimed to evaluate the biocompatibility and biodegradation of ACPMetals in mice subcutaneous tissue. The materials were physicochemically characterized with Fourier Transform InfraRed (FTIR), X-Ray Diffraction (XRD), and Atomic Absorption Spectrometry (AAS). Balb-C mice (n = 45) were randomly divided into three groups: carbonated hydroxyapatite, CHA (n = 15), ACPMetals (n = 15), and without implantation of material (SHAM, n = 15). The groups were subdivided into three experimental periods (1, 3, and 9 weeks). The samples were processed histologically for descriptive and semiquantitative evaluation of the biological effect of biomaterials according to ISO 10993-6:2016. The ACPMetals group was partially biodegradable; however, it presented a severe irritating reaction after 1 and 3 weeks and moderately irritating after nine weeks. Future studies with other concentrations and other metals should be carried out to mimic biological apatite.

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A New Model for Quantitative In Vivo Microscopic Analysis of Thrombus Formation and Vascular Recanalisation: The Ear of the Hairless (hr/hr) Mouse

Thrombosis and Haemostasis ◽

10.1055/s-0038-1665420 ◽

1997 ◽

Vol 78 (05) ◽

pp. 1408-1414 ◽

Cited By ~ 25

Author(s):

Frank Roesken ◽

Martin Ruecker ◽

Brigitte Vollmar ◽

Nicole Boeckel ◽

Eberhard Morgenstern ◽

...

Keyword(s):

Endothelial Cell ◽

Light Exposure ◽

Thrombus Formation ◽

Microscopic Analysis ◽

Cell Interaction ◽

Vascular Perfusion ◽

Vessel Occlusion ◽

Endothelial Cell Interaction ◽

Platelet Deposition

SummaryThe alteration of rheological blood properties as well as deterioration of vascular perfusion conditions and cell-cell interactions are major determinants of thrombus formation. Herein, we present an experimental model which allows for quantitative in vivo microscopic analysis of these determinants during both thrombus formation and vascular recanalisation. The model does not require surgical preparation procedures, and enables for repeated analysis of identical microvessels over time periods of days or months, respectively. After i.v. administration of FITC-dextran thrombus formation was induced photochemically by light exposure to individual arterioles and venules of the ear of ten anaesthetised hairless mice. In venules, epiillumination induced rapid thrombus formation with first platelet deposition after 0.59 ± 0.04 min and complete vessel occlusion within 7.48 ±1.31 min. After a 24-h time period, 75% of the thrombosed venules were found recanalised. Marked leukocyte-endothelial cell interaction in those venules indicated persistent endothelial cell activation and/or injury, even after an observation period of 7 days. In arterioles, epi-illumination provoked vasomotion, while thrombus formation was significantly (p <0.05) delayed with first platelet deposition after 2.32 ± 0.22 min and complete vessel occlusion within 20.07 ±3.84 min. Strikingly, only one of the investigated arterioles was found recanalised after 24 h, which, however, did not show leukocyte-endothelial cell interaction. Heparin (300 U/kg, i.v.) effectively counteracted the process of thrombus formation in this model, including both first platelet deposition and vessel occlusion. We conclude that the model of the ear of the hairless mouse allows for distinct in vivo analysis of arteriolar and venular thrombus formation/ recanalisation, and, thus, represents an interesting tool for the study of novel antithrombotic and thrombolytic strategies, respectively.

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Dehulled Adlay Consumption Modulates Blood Pressure in Spontaneously Hypertensive Rats and Overweight and Obese Young Adults

Nutrients ◽

10.3390/nu13072305 ◽

2021 ◽

Vol 13 (7) ◽

pp. 2305

Author(s):

Wan-Ju Yeh ◽

Jung Ko ◽

Wei-Yi Cheng ◽

Hsin-Yi Yang

Keyword(s):

Blood Pressure ◽

Daily Intake ◽

Experimental Period ◽

Overweight And Obesity ◽

Hypertensive Rats ◽

Spontaneously Hypertensive ◽

Beneficial Effects ◽

Underlying Mechanisms ◽

Grain Foods

High blood pressure is a crucial risk factor for many cardiovascular diseases, and a diet rich in whole-grain foods may modulate blood pressure. This study investigated the effects of dehulled adlay consumption on blood pressure in vivo. We initially fed spontaneous hypertensive rats diets without (SHR group) or with 12 or 24% dehulled adlay (SHR + LA and SHR + HA groups), and discovered that it could limit blood pressure increases over a 12-week experimental period. Although we found no significant changes in plasma, heart, and kidney angiotensin-converting enzyme activities, both adlay-consuming groups had lower endothelin-1 and creatinine concentrations than the SHR group; the SHR + HA group also had lower aspartate aminotransferase and uric acid levels than the SHR group did. We later recruited 23 participants with overweight and obesity, and they consumed 60 g of dehulled adlay daily for a six-week experimental period. At the end of the study, we observed a significant decrease in the group’s systolic blood pressure (SBP), and the change in SBP was even more evident in participants with high baseline SBP. In conclusion, our results suggested that daily intake of dehulled adlay had beneficial effects in blood-pressure management. Future studies may further clarify the possible underlying mechanisms for the consuming of dehulled adlay as a beneficial dietary approach for people at risk of hypertension.

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Effects of chitosan-collagen dressing on wound healing in vitro and in vivo assays

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800021989698 ◽

2021 ◽

Vol 19 ◽

pp. 228080002198969

Author(s):

Min-Xia Zhang ◽

Wan-Yi Zhao ◽

Qing-Qing Fang ◽

Xiao-Feng Wang ◽

Chun-Ye Chen ◽

...

Keyword(s):

Wound Healing ◽

Wound Dressing ◽

Type I Collagen ◽

Inhibition Zone ◽

Negative Control ◽

Type I ◽

Nih3t3 Cells ◽

Post Operation

The present study was designed to fabricate a new chitosan-collagen sponge (CCS) for potential wound dressing applications. CCS was fabricated by a 3.0% chitosan mixture with a 1.0% type I collagen (7:3(w/w)) through freeze-drying. Then the dressing was prepared to evaluate its properties through a series of tests. The new-made dressing demonstrated its safety toward NIH3T3 cells. Furthermore, the CCS showed the significant surround inhibition zone than empty controls inoculated by E. coli and S. aureus. Moreover, the moisture rates of CCS were increased more rapidly than the collagen and blank sponge groups. The results revealed that the CCS had the characteristics of nontoxicity, biocompatibility, good antibacterial activity, and water retention. We used a full-thickness excisional wound healing model to evaluate the in vivo efficacy of the new dressing. The results showed remarkable healing at 14th day post-operation compared with injuries treated with collagen only as a negative control in addition to chitosan only. Our results suggest that the chitosan-collagen wound dressing were identified as a new promising candidate for further wound application.

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Optimizing cisplatin delivery to triple-negative breast cancer through novel EGFR aptamer-conjugated polymeric nanovectors

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-02039-w ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Lisa Agnello ◽

Silvia Tortorella ◽

Annachiara d’Argenio ◽

Clarissa Carbone ◽

Simona Camorani ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Tumor Targeting ◽

Triple Negative ◽

Ex Vivo ◽

Treatment Options ◽

Negative Control ◽

Therapeutic Effects ◽

Metastatic Setting

Abstract Background Management of triple-negative breast cancer (TNBC) is still challenging because of its aggressive clinical behavior and limited targeted treatment options. Cisplatin represents a promising chemotherapeutic compound in neoadjuvant approaches and in the metastatic setting, but its use is limited by scarce bioavailability, severe systemic side effects and drug resistance. Novel site-directed aptamer-based nanotherapeutics have the potential to overcome obstacles of chemotherapy. In this study we investigated the tumor targeting and the anti-tumorigenic effectiveness of novel cisplatin-loaded and aptamer-decorated nanosystems in TNBC. Methods Nanotechnological procedures were applied to entrap cisplatin at high efficacy into polymeric nanoparticles (PNPs) that were conjugated on their surface with the epidermal growth factor receptor (EGFR) selective and cell-internalizing CL4 aptamer to improve targeted therapy. Internalization into TNBC MDA-MB-231 and BT-549 cells of aptamer-decorated PNPs, loaded with BODIPY505-515, was monitored by confocal microscopy using EGFR-depleted cells as negative control. Tumor targeting and biodistribution was evaluated by fluorescence reflectance imaging upon intravenously injection of Cyanine7-labeled nanovectors in nude mice bearing subcutaneous MDA-MB-231 tumors. Cytotoxicity of cisplatin-loaded PNPs toward TNBC cells was evaluated by MTT assay and the antitumor effect was assessed by tumor growth experiments in vivo and ex vivo analyses. Results We demonstrate specific, high and rapid uptake into EGFR-positive TNBC cells of CL4-conjugated fluorescent PNPs which, when loaded with cisplatin, resulted considerably more cytotoxic than the free drug and nanovectors either unconjugated or conjugated with a scrambled aptamer. Importantly, animal studies showed that the CL4-equipped PNPs achieve significantly higher tumor targeting efficiency and enhanced therapeutic effects, without any signs of systemic toxicity, compared with free cisplatin and untargeted PNPs. Conclusions Our study proposes novel and safe drug-loaded targeted nanosystems for EGFR-positive TNBC with excellent potential for the application in cancer diagnosis and therapy.

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