scholarly journals Disproportionate Effect of Sub-Micron Topography on Osteoconductive Capability of Titanium

2019 ◽  
Vol 20 (16) ◽  
pp. 4027 ◽  
Author(s):  
Juri Saruta ◽  
Nobuaki Sato ◽  
Manabu Ishijima ◽  
Takahisa Okubo ◽  
Makoto Hirota ◽  
...  
Keyword(s):  
Rough Surface ◽  
Cell Attachment ◽  
Biological Effects ◽  
Calcium Deposition ◽  
Male Rat ◽  
Bone Implant ◽  
Micro Scale ◽  
Titanium Surfaces ◽  
Implant Integration

Titanium micro-scale topography offers excellent osteoconductivity and bone–implant integration. However, the biological effects of sub-micron topography are unknown. We compared osteoblastic phenotypes and in vivo bone and implant integration abilities between titanium surfaces with micro- (1–5 µm) and sub-micro-scale (0.1–0.5 µm) compartmental structures and machined titanium. The calculated average roughness was 12.5 ± 0.65, 123 ± 6.15, and 24 ± 1.2 nm for machined, micro-rough, and sub-micro-rough surfaces, respectively. In culture studies using bone marrow-derived osteoblasts, the micro-rough surface showed the lowest proliferation and fewest cells attaching during the initial stage. Calcium deposition and expression of osteoblastic genes were highest on the sub-micro-rough surface. The bone–implant integration in the Sprague–Dawley male rat femur model was the strongest on the micro-rough surface. Thus, the biological effects of titanium surfaces are not necessarily proportional to the degree of roughness in osteoblastic cultures or in vivo. Sub-micro-rough titanium ameliorates the disadvantage of micro-rough titanium by restoring cell attachment and proliferation. However, bone integration and the ability to retain cells are compromised due to its lower interfacial mechanical locking. This is the first report on sub-micron topography on a titanium surface promoting osteoblast function with minimal osseointegration.

scholarly journals Disproportionate Effect of Sub-Micron Topography on Osteoconductive Capability of Titanium

2019 ◽  
Author(s):  
Juri Saruta ◽  
Nobuaki Sato ◽  
Manabu Ishijima ◽  
Takahisa Okubo ◽  
Makoto Hirota ◽  
...  
Keyword(s):  
Rough Surface ◽  
Cell Attachment ◽  
Biological Effects ◽  
Calcium Deposition ◽  
Average Roughness ◽  
Machined Surface ◽  
Micro Scale ◽  
Titanium Surfaces ◽  
Implant Integration

Titanium micro-scale topography results in excellent osteoconductivity and bone-implant integration. However, the biological effects of sub-micron topography are unknown. We compared osteoblastic phenotypes and in vivo bone and implant integration abilities between titanium surfaces with micro- (1–5 µm) and sub-micro-scale (0.1–0.5 µm) topographies and machined titanium. Average roughness was 12.5 ± 0.65 nm, 123 ± 6.15 nm, and 24 ± 1.2 nm for machined, micro-rough, and sub-micro-rough surfaces, respectively. The micro-rough surface showed the fewest cells attaching during the initial stage and the lowest proliferation. Calcium deposition and expression of osteoblastic genes were highest on the sub-micro-rough surface and lowest on the machined surface. Bone-to-implant integration was strongest for the micro-rough surface, consistent with it having the greatest ability to retain cells in vitro. Thus, the biological effects of titanium surfaces are not necessarily proportional to the degree of roughness in osteoblastic cultures or in vivo. Sub-micro-rough titanium ameliorates the disadvantage of micro-rough titanium by restoring cell attachment and proliferation and enhances the rate of osteoblastic differentiation over that of micro-rough titanium; however, bone integration and the ability to retain cells are compromised due to its lower interfacial mechanical locking compared to that of micro-rough titanium.

scholarly journals Extracellular matrix modulates the biological effects of melatonin in mesenchymal stem cells

2014 ◽  
Vol 223 (2) ◽  
pp. 167-180 ◽  
Author(s):  
Fan He ◽  
Xiaozhen Liu ◽  
Ke Xiong ◽  
Sijin Chen ◽  
Long Zhou ◽  
...  
Keyword(s):  
Stem Cells ◽  
Extracellular Matrix ◽  
Mesenchymal Stem Cells ◽  
Biological Effects ◽  
Matrix Composition ◽  
Calcium Deposition ◽  
Specific Gene ◽  
Skeletal Tissue ◽  
Underlying Mechanisms

Both self-renewal and lineage-specific differentiation of mesenchymal stem cells (MSCs) are triggered by theirin vivomicroenvironment including the extracellular matrix (ECM) and secreted hormones. The ECM may modulate the physiological functions of hormones by providing binding sites and by regulating downstream signaling pathways. Thus, the purpose of this study was to evaluate the degree of adsorption of melatonin to a natural cell-deposited ECM and the effects of this interaction on the biological functions of melatonin in human bone marrow-derived MSCs (BM-MSCs). The fibrillar microstructure, matrix composition, and melatonin-binding affinity of decellularized ECM were characterized. The cell-deposited ECM improved melatonin-mediated cell proliferation by 31.4%, attenuated accumulation of intracellular reactive oxygen species accumulation, and increased superoxide dismutase (SOD) mRNA and protein expression. Interaction with ECM significantly enhanced the osteogenic effects of melatonin on BM-MSCs by increasing calcium deposition by 30.5%, up-regulating osteoblast-specific gene expression and down-regulating matrix metalloproteinase (MMP) expression. The underlying mechanisms of these changes in expression may involve intracellular antioxidant enzymes, because osteoblast-specific genes were down-regulated, whereas MMP expression was up-regulated, in the presence of SOD-specific inhibitors. Collectively, our findings indicate the importance of native ECM in modulating the osteoinductive and antioxidant effects of melatonin and provide a novel platform for studying the biological actions of growth factors or hormones in a physiologically relevant microenvironment. Moreover, a better understanding of the enhancement of MSC growth and osteogenic differentiation resulting from the combination of ECM and melatonin could improve the design of graft substitutes for skeletal tissue engineering.

Does surface anodisation of titanium implants change osseointegration and make their extraction from bone any easier?

2008 ◽  
Vol 21 (03) ◽  
pp. 202-210 ◽  
Author(s):  
J. Langhoff ◽  
J. Mayer ◽  
L. Faber ◽  
S. Kaestner ◽  
G. Guibert ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Titanium Implant ◽  
Titanium Implants ◽  
Implant Surface ◽  
Bone Implant ◽  
High Bone ◽  
Titanium Surfaces ◽  
Anodized Titanium ◽  
Titanium Implant Surface

Summary Objectives: Titanium implants have a tendency for high bone-implant bonding, and, in comparison to stainless steel implants are more difficult to remove. The current study was carried out to evaluate, i) the release strength of three selected anodized titanium surfaces with increased nanohardness and low roughness, and ii) bone-implant bonding in vivo. These modified surfaces were intended to give improved anchorage while facilitating easier removal of temporary implants. Material and methods: The new surfaces were referenced to a stainless steel implant and a standard titanium implant surface (TiMAX™). In a sheep limb model, healing period was 3 months. Bone-implant bonding was evaluated either biomechanically or histologically. Results: The new surface anodized screws demonstrated similar or slightly higher bone-implantcontact (BIC) and torque release forces than the titanium reference. The BIC of the stainless steel implants was significant lower than two of the anodized surfaces (p=0.04), but differences between stainless steel and all titanium implants in torque release forces were not significant (p=0.06). Conclusion: The new anodized titanium surfaces showed good bone-implant bonding despite a smooth surface and increased nanohardness. However, they failed to facilitate implant removal at 3 months.

Synergistic effects of elastic modulus and surface topology of Ti-based implants on early osseointegration

RSC Advances ◽  
2016 ◽  
Vol 6 (49) ◽  
pp. 43685-43696 ◽  
Author(s):  
Xiaohan Dai ◽  
Xuehui Zhang ◽  
Mingming Xu ◽  
Ying Huang ◽  
Boon Chin Heng ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Synergistic Effect ◽  
Osteogenic Differentiation ◽  
Cell Attachment ◽  
Synergistic Effects ◽  
Surface Topology ◽  
Ti Alloy ◽  
Micro Scale

Elastic modulus and surface micro-scale topographical structure of Ti alloy implants have a synergistic effect on cell attachment, osteogenic differentiation of rBMSCs in vitro and early osseointegration in vivo.

scholarly journals UV-Photofunctionalization of Titanium Promotes Mechanical Anchorage in A Rat Osteoporosis Model

2020 ◽  
Vol 21 (4) ◽  
pp. 1235 ◽  
Author(s):  
Takashi Taniyama ◽  
Juri Saruta ◽  
Naser Mohammadzadeh Rezaei ◽  
Kourosh Nakhaei ◽  
Amirreza Ghassemi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Contact Angle ◽  
Alkaline Phosphatase ◽  
Uv Light ◽  
Bone Implant ◽  
Post Menopausal Osteoporosis ◽  
Ovx Rats ◽  
Implant Integration ◽  
Pre Treatment

Effects of UV-photofunctionalization on bone-to-titanium integration under challenging systemic conditions remain unclear. We examined the behavior and response of osteoblasts from sham-operated and ovariectomized (OVX) rats on titanium surfaces with or without UV light pre-treatment and the strength of bone-implant integration. Osteoblasts from OVX rats showed significantly lower alkaline phosphatase, osteogenic gene expression, and mineralization activities than those from sham rats. Bone density variables in the spine were consistently lower in OVX rats. UV-treated titanium was superhydrophilic and the contact angle of ddH2O was ≤5°. Titanium without UV treatment was hydrophobic with a contact angle of ≥80°. Initial attachment to titanium, proliferation, alkaline phosphatase activity, and gene expression were significantly increased on UV-treated titanium compared to that on control titanium in osteoblasts from sham and OVX rats. Osteoblastic functions compromised by OVX were elevated to levels equivalent to or higher than those of sham-operated osteoblasts following culture on UV-treated titanium. The strength of in vivo bone-implant integration for UV-treated titanium was 80% higher than that of control titanium in OVX rats and even higher than that of control implants in sham-operated rats. Thus, UV-photofunctionalization effectively enhanced bone-implant integration in OVX rats to overcome post-menopausal osteoporosis-like conditions.

Overtraining of aerobic physical exercise reduce rats (Rattus norvegicus) memory

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Ni Made Ridla Parwata
Keyword(s):  
Body Weight ◽  
Physical Exercise ◽  
Rattus Norvegicus ◽  
Research Method ◽  
Male Rat ◽  
Control Group ◽  
Adult Male Rat ◽  
The Subject ◽  
Heavy Training

Overtraining syndrome is a decrease in physical capacity, emotions and immunity due to training that is too often without adequate periods of rest. Overtraining is often experienced by athletes who daily undergo heavy training with short break periods. This research aims to look at the effect of overtraining aerobic physical exercise on memory in mice. The research method was experimental in vivo with the subject of adult male rat (Rattus Norvegicus) Winstar strain aged 8-10 weeks, body weight 200-250 gr. Divided into three groups, namely the control group, aerobic group and overtraining group. The results of memory tests with water E Maze showed an increase in the duration of travel time and the number of animal errors made by the overtraining group (p = 0.003). This study concludes that overtraining aerobic physical exercise can reduce memory in rat hippocampus.

The role of aromatic microbial metabolites

2018 ◽  
pp. 97-108
Author(s):  
Н.В. Белобородова ◽  
В.В. Мороз ◽  
А.Ю. Бедова
Keyword(s):  
Process Integration ◽  
Biological Effects ◽  
Clinical Findings ◽  
Multiple Organ ◽  
Critical Conditions ◽  
Clear Understanding ◽  
Microbial Metabolites ◽  
Blood Concentrations

Интеграция метаболизма макроорганизма и его микробиоты, обеспечивающая в норме симбиоз и саногенез, нарушается при заболеваниях, травме, критическом состоянии, и вектор взаимодействия может изменяться в пользу прокариотов по принципу «метаболиты бактерий - против хозяина». Анализ литературы показал, что, с одной стороны, имеется живой интерес к ароматическим микробным метаболитам, с другой - отсутствует четкое представление об их роли в организме человека. Публикации, касающиеся ряда ароматических микробных метаболитов (фенилкарбоновых кислот, ФКК), как правило, не связаны между собой по тематике и направлены на решение тех или иных прикладных задач в разных областях биологии и медицины. Цель обзора - анализ информации о происхождении, биологических эффектах ФКК в экспериментах in vitro и in vivo , и клинических наблюдениях. Обобщая результаты приведенных в обзоре исследований на клеточном, субклеточном и молекулярном уровнях, логично предположить участие ароматических микробных метаболитов в патогенезе полиорганной недостаточности при сепсисе. Наиболее перспективным для раскрытия роли ароматических микробных метаболитов представляется изучение механизмов вторичной почечной недостаточности и септической энцефалопатии. Важным направлением для будущих исследований является изучение влияния продуктов микробной биодеградации ароматических соединений на развитие диссеминированного внутрисосудистого свертывания крови, артериальной гипотензии и септического шока. Результаты дальнейших исследований будут иметь не только фундаментальное значение, но и обогатят практическую медицину новыми диагностическими и лечебными технологиями. Significant increases in blood concentrations of some aromatic metabolites (phenylcarboxylic acids, PhCAs) in patients with sepsis have been previously shown. Enhanced bacterial biodegradation of aromatic compounds has been demonstrated to considerably contribute to this process. Integration of macroorganism metabolism and its microbiota, which provides normal symbiosis and sanogenesis, is disturbed in diseases, trauma, and critical conditions. Direction of this interaction may change in favor of prokaryotes according to the principle, “bacterial metabolites are against the host”. Analysis of literature showed a particular interest of many investigators to aromatic microbial metabolites. However, there is no clear understanding of their role in the human body. Publications on PhCAs are generally not thematically interrelated and usually focus on solving applied tasks in different fields of biology and medicine. The aim of this work was to consolidate existing information about origin and biological effects of PhCAs in in vitro / in vivo experiments and some clinical findings. The presented summary of reported data from studies performed at cellular, sub-cellular, and molecular levels suggests participation of aromatic microbial metabolites in the pathogenesis of multiple organ failure in sepsis. Studying mechanisms of secondary renal failure and septic encephalopathy is most promising for discovering the function of aromatic microbial metabolites. Effects of microbial biodegradation products of aromatic substances on development of disseminated intravascular coagulation, hypotension, and septic shock are an important challenge for future studies. Results of further investigations will be not only fundamental, but will also enrich medical practice with new diagnostic and therapeutic technologies.

Antioxidant Activity, Phenolic Content and Hematoprotective Effects of Cleome arabica Polyphenolic Leaf Extract

2019 ◽  
Author(s):  
C. Tigrine ◽  
A. Kameli
Keyword(s):  
Antioxidant Activity ◽  
Biological Effects ◽  
Reducing Power ◽  
Hematological Toxicity ◽  
Protective Effects ◽  
Ferrous Ions ◽  
Polyphenolic Extract ◽  
Cleome Arabica

In this study a polyphenolic extract from Cleome arabica leaves (CALE) was investigated for its antioxidant activity in vitro using DPPH•, metal chelating and reducing power methods and for its protective effects against AraC-induced hematological toxicity in vivo using Balb C mice. Results indicated that CALE exhibited a strong and dose-dependent scavenging activity against the DPPH• free radical (IC50 = 4.88 μg/ml) and a high reducing power activity (EC50 = 4.85 μg/ml). Furthermore, it showed a good chelating effects against ferrous ions (IC50 = 377.75 μg/ml). The analysis of blood showed that subcutaneous injection of AraC (50 mg/kg) to mice during three consecutive days caused a significant myelosupression (P < 0.05). The combination of CALE and AraC protected blood cells from a veritable toxicity. Where, the number of the red cells, the amount of hemoglobin and the percentage of the hematocrite were significantly high. On the other hand, AraC cause an elevation of body temperature (39 °C) in mice. However, the temperature of the group treated with CALE and AraC remained normal and did not exceed 37.5 °C. The observed biological effects of CALE, in vitro as well as in vivo, could be due to the high polyphenol and flavonoid contents. In addition, the antioxidant activity of CALE suggested to be responsible for its hematoprotective effect.

Chickpea (Cicer arietinum L.) Lectin Exhibit Inhibition of ACE-I, α-amylase and α-glucosidase Activity

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  
Keyword(s):  
Biological Effects ◽  
Exchange Chromatography ◽  
Health Concern ◽  
Carbohydrate Binding ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ic50 Values ◽  
Chickpea Lectin

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.

Chemosensitizing Activity of Histone Deacetylases Inhibitory Cyclic Hydroxamic Acids for Combination Chemotherapy of Lymphatic Leukemia

2018 ◽  
Vol 18 (4) ◽  
pp. 365-371 ◽  
Author(s):  
Denis V. Mishchenko ◽  
Margarita E. Neganova ◽  
Elena N. Klimanova ◽  
Tatyana E. Sashenkova ◽  
Sergey G. Klochkov ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Acute Toxicity ◽  
Histone Deacetylases ◽  
Hydroxamic Acids ◽  
Water Soluble ◽  
Male Rat ◽  
Hybrid Male ◽  
Cyclic Hydroxamic Acids

Background: Anti-tumor effect of hydroxamic acid derivatives is largely connected with its properties as efficient inhibitors of histone deacetylases, and other metalloenzymes involved in carcinogenesis. Objective: The work was aimed to (i) determine the anti-tumor and chemosensitizing activity of the novel racemic spirocyclic hydroxamic acids using experimental drug sensitive leukemia P388 of mice, and (ii) determine the structure-activity relationships as metal chelating and HDAC inhibitory agents. Method: Outbreed male rat of 200-220 g weights were used in biochemical experiments. In vivo experiments were performed using the BDF1 hybrid male mice of 22-24 g weight. Lipid peroxidation, Fe (II) -chelating activity, HDAC fluorescent activity, anti-tumor and anti-metastatic activity, acute toxicity techniques were used in this study. Results: Chemosensitizing properties of water soluble cyclic hydroxamic acids (CHA) are evaluated using in vitro activities and in vivo methods and found significant results. These compounds possess iron (II) chelating properties, and slightly inhibit lipid peroxidation. CHA prepared from triacetonamine (1a-e) are more effective Fe (II) ions cheaters, as compared to CHA prepared from 1- methylpiperidone (2a-e). The histone deacetylase (HDAC) inhibitory activity, lipophilicity and acute toxicity were influenced by the length amino acids (size) (Glycine < Alanine < Valine < Leucine < Phenylalanine). All compounds bearing spiro-N-methylpiperidine ring (2a-e) are non-toxic up to 1250 mg/kg dose, while compounds bearing spiro-tetramethylpiperidine ring (1a-e) exhibit moderate toxicity which increases with increasing lipophility, but not excite at 400 mg/kg. Conclusion: It was shown that the use of combination of non-toxic doses of cisplatin (cPt) or cyclophosphamide with CHA in most cases result in the appearance of a considerable anti-tumor effect of cytostatics. The highest chemosensitizing activity with respect to leukemia Р388 is demonstrated by the CHA derivatives of Valine 1c or 2c.

Sign in / Sign up

Export Citation Format

Share Document