scholarly journals Ultraviolet irradiation improves the hydrophilicity and osteo-conduction of hydroxyapatite

2020 ◽  
Author(s):  
Sho Kaneko ◽  
Yuji Yamamoto ◽  
Kaniichro Wada ◽  
Gentaro Kumagai ◽  
Yoshifumi Harada ◽  
...  
Keyword(s):  
Contact Angle ◽  
Uv Irradiation ◽  
Uv Light ◽  
Water Drop ◽  
Area Ratio ◽  
Bone Volume ◽  
High Porosity ◽  
Bone Area ◽  
Dental Surgery ◽  
Significant Difference

Abstract Background: Treating a titanium or titanium alloy implant with ultraviolet (UV) light is known to improve its associated cell growth and osseointegration. However, little is known about the effect of UV irradiation on hydroxyapatite (HA), which is also used frequently in orthopaedic and dental surgery. Here we examined the effect of UV irradiation on the hydrophilicity of HA, and on its osteoconduction ability in rats. Methods: HA implants of low and high porosity were treated with UV light, and photofunctionalisation was assessed by the contact angle of a water drop on the surface. HA implants were also inserted into rat femurs, and the rats were killed two or four weeks later. The bone volume and bone area ratio were calculated from microcomputed tomography and histological data. Results: The contact angle of a water drop on HA implants of both porosities was significantly reduced after UV irradiation. In the rat femurs, there was no significant difference in the bone volume between the UV light-treated and control implants at two or four weeks. The bone area ratio for the UV light-treated versus control implants was significantly increased at two weeks, but there was no significant difference at four weeks. Conclusions: The surface of UV-irradiated HA disks was hydrophilic, in contrast to that of non-irradiated HA disks. Photofunctionalisation accelerated the increase in the bone area ratio in the early healing stage. This technology can be applied to surgical cases requiring the early fusion of bone and HA.

scholarly journals Ultraviolet irradiation improves the hydrophilicity and osteo-conduction of hydroxyapatite

2020 ◽  
Author(s):  
Sho Kaneko ◽  
Yuji Yamamoto ◽  
Kaniichro Wada ◽  
Gentaro Kumagai ◽  
Yoshifumi Harada ◽  
...  
Keyword(s):  
Contact Angle ◽  
Uv Irradiation ◽  
Uv Light ◽  
Water Drop ◽  
Area Ratio ◽  
Bone Volume ◽  
High Porosity ◽  
Bone Area ◽  
Dental Surgery ◽  
Significant Difference

Abstract Background Treating a titanium or titanium alloy implant with ultraviolet (UV) light is known to improve its associated cell growth and osseointegration. However, little is known about the effect of UV irradiation on hydroxyapatite (HA), which is also used frequently in orthopaedic and dental surgery. Here we examined the effect of UV irradiation on the hydrophilicity of HA, and on its osteoconduction ability in rats. Methods HA implants of low and high porosity were treated with UV light, and photofunctionalisation was assessed by the contact angle of a water drop on the surface. HA implants were also inserted into rat femurs, and the rats were killed two or four weeks later. The bone volume and bone area ratio were calculated from microcomputed tomography and histological data. Results The contact angle of a water drop on HA implants of both porosities was significantly reduced after UV irradiation. In the rat femurs, there was no significant difference in the bone volume between the UV light-treated and control implants at two or four weeks. The bone area ratio for the UV light-treated versus control implants was significantly increased at two weeks, but there was no significant difference at four weeks. Conclusions The surface of UV-irradiated HA disks was hydrophilic, in contrast to that of non-irradiated HA disks. Photofunctionalisation accelerated the increase in the bone area ratio in the early healing stage. This technology can be applied to surgical cases requiring the early fusion of bone and HA.

scholarly journals Ultraviolet irradiation improves the hydrophilicity and osteo-conduction of hydroxyapatite

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Sho Kaneko ◽  
Yuji Yamamoto ◽  
Kanichiro Wada ◽  
Gentaro Kumagai ◽  
Yoshifumi Harada ◽  
...  
Keyword(s):  
Contact Angle ◽  
Uv Irradiation ◽  
Uv Light ◽  
Water Drop ◽  
Area Ratio ◽  
Bone Volume ◽  
High Porosity ◽  
Bone Area ◽  
Dental Surgery ◽  
Significant Difference

Abstract Background Treating a titanium or titanium alloy implant with ultraviolet (UV) light is known to improve its associated cell growth and osseointegration. However, little is known about the effect of UV irradiation on hydroxyapatite (HA), which is also used frequently in orthopaedic and dental surgery. Here we examined the effect of UV irradiation on the hydrophilicity of HA, and on its osteoconduction ability in rats. Methods HA implants of low and high porosity were treated with UV light, and photofunctionalisation was assessed by the contact angle of a water drop on the surface. HA implants were also inserted into rat femurs, and the rats were killed 2 or 4 weeks later. The bone volume and bone area ratio were calculated from microcomputed tomography and histological data. Results The contact angle of a water drop on HA implants of both porosities was significantly reduced after UV irradiation. In the rat femurs, there was no significant difference in the bone volume between the UV light-treated and control implants at 2 or 4 weeks. The bone area ratio for the UV light-treated versus control implants was significantly increased at 2 weeks, but there was no significant difference at 4 weeks. Conclusions The surface of UV-irradiated HA disks was hydrophilic, in contrast to that of non-irradiated HA disks. Photofunctionalisation accelerated the increase in the bone area ratio in the early healing stage. This technology can be applied to surgical cases requiring the early fusion of bone and HA.

Correlation of Superhydrophilicity and Photocatalytic Activity in the TiO2-Based Porous Thin Films

2006 ◽  
Vol 510-511 ◽  
pp. 54-57 ◽  
Author(s):  
Seung Yong Chai ◽  
Jin Koo Park ◽  
Ho Kun Kim ◽  
Wan In Lee
Keyword(s):  
Contact Angle ◽  
Photocatalytic Activity ◽  
Uv Irradiation ◽  
Uv Light ◽  
Irradiation Time ◽  
Colloidal Suspension ◽  
Initial Point ◽  
Film Surface ◽  
Contact Angles ◽  
Tio2 Films

Transparent TiO2, WO3-TiO2, and MoO3-TiO2 films were prepared by spin-coating each colloidal suspension. The monolayer coverage of WO3 on the surface of TiO2 greatly increased the photocatalytic activity in the decomposition of gaseous 2-propanol, whereas the addition of MoO3 considerably decreased the photocatalytic reaction of TiO2. For the estimation of superhydrophilicity, the change of contact angles between the water drop and the film surface was measured as a function of UV-irradiation time. The measured contact angle of WO3-TiO2 film was considerably lower than that of TiO2 before the UV-irradiation, and it decreased to the minimum value about 4 times faster than that of pure TiO2 films with the irradiation of UV light. On the other hand, MoO3-TiO2 films showed a low contact angle at initial point, but their contact angle was very slowly decreased under the UV light. The initial low contact angles suggest the high hydrophilic character of WO3-TiO2 and MoO3-TiO2 films with high Lewis surface acidities. The observed trend suggests that the superhydrophilicity is closely related to the photocatalytic activity.

Controlling porosity and density of nanocellulose aerogels for superhydrophobic light materials

TAPPI Journal ◽  
2018 ◽  
Vol 17 (03) ◽  
pp. 145-153 ◽  
Author(s):  
Chengua Yu ◽  
Feng Wang ◽  
Shiyu Fu ◽  
Lucian Lucia
Keyword(s):  
Contact Angle ◽  
Freeze Drying ◽  
Engine Oil ◽  
High Porosity ◽  
Water Mixture ◽  
Waste Engine Oil ◽  
Hydrophobically Modified ◽  
Static Contact ◽  
Oil Water ◽  
Hydrophobic Material

A very low-density oil-absorbing hydrophobic material was fabricated from cellulose nanofiber aerogels–coated silane substances. Nanocellulose aerogels (NCA) superabsorbents were prepared by freeze drying cellulose nanofibril dispersions at 0.2%, 0.5%, 0.8%, 1.0%, and 1.5% w/w. The NCA were hydrophobically modified with methyltrimethoxysilane. The surface morphology and wettability were characterized by scanning electron microscopy and static contact angle. The aerogels displayed an ultralow density (2.0–16.7 mg·cm-3), high porosity (99.9%–98.9%), and superhydrophobicity as evidenced by the contact angle of ~150° that enabled the aerogels to effectively absorb oil from an oil/water mixture. The absorption capacities of hydrophobic nanocellulose aerogels for waste engine oil and olive oil could be up to 140 g·g-1 and 179.1 g·g-1, respectively.

scholarly journals Effect of Water Leaching on Photodegraded Scots Pine and Spruce Timbers Monitored by FTIR Spectroscopy

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 833
Author(s):  
Edina Preklet ◽  
László Tolvaj ◽  
Eszter Visi-Rajczi ◽  
Tamás Hofmann
Keyword(s):  
Ftir Spectroscopy ◽  
Scots Pine ◽  
Uv Irradiation ◽  
Chemical Elements ◽  
Uv Light ◽  
Carbonyl Groups ◽  
Water Leaching ◽  
Absorption Bands ◽  
Chemical Changes ◽  
Absorption Increase

The goal of this research was the systematic study and comparison of the divided individual effects of UV light irradiation and water leaching during artificial weathering. Spruce (Picea abies Karst.) and Scots pine (Pinus sylvestris L.) samples were irradiated by ultraviolet (UV) light. Another sequence of samples was treated with the combination of UV irradiation and water leaching. The total extent of UV treatment was 20 days for both series of samples. Time relation of UV irradiation and water leaching was 2:1. The chemical changes were observed by FTIR spectroscopy. The difference spectrum was used for determination of the chemical changes. Degradation of lignin was greater for the leached samples than for the pure UV treated samples. Scots pine suffered greater lignin degradation than spruce, and produced higher absorption increase on the absorption region of unconjugated carbonyls. The unconjugated carbonyl groups were the most responsive chemical elements to leaching. Spruce was more susceptible to leaching of unconjugated carbonyl groups than Scots pine. Two absorption bands of unconjugated carbonyl groups at 1706 and 1764 cm−1 wavenumbers were produced by photodegradation. The absorption band at 1764 cm−1 was more sensitive to water leaching than the band at 1706 cm−1.

scholarly journals UV-induced neuronal degeneration in the rat cerebral cortex

2021 ◽  
Author(s):  
Mariko Nakata ◽  
Masayuki Shimoda ◽  
Shinya Yamamoto
Keyword(s):  
Uv Irradiation ◽  
Neuronal Degeneration ◽  
Uv Light ◽  
Brain Lesion ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Heme Oxygenase 1 ◽  
Dependent Manner ◽  
Focal Brain Injury ◽  
The Brain ◽  
And Oxidative Stress

Abstract Irradiation with ultraviolet (UV) light on the cortical surface can induce a focal brain lesion (UV lesion) in rodents. In the present study, we investigated the process of establishing a UV lesion. Rats underwent UV irradiation (365 nm wavelength, 2.0 mWh) over the dura, and time-dependent changes in the cortical tissue were analyzed histologically. We found that the majority of neurons in the lesion started to degenerate within 24 hours and the rest disappeared within 5 days after irradiation. UV-induced neuronal degeneration progressed in a layer-dependent manner. Moreover, UV-induced terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positivity and heme oxygenase-1 (HO-1) immunoreactivity were also detected. These findings suggest that UV irradiation in the brain can induce gradual neural degeneration and oxidative stress. Importantly, UV vulnerability may vary among cortical layers. UV-induced cell death may be due to apoptosis; however, there remains a possibility that UV-irradiated cells were degenerated via processes other than apoptosis. The UV lesion technique will not only assist in investigating brain function at a targeted site but may also serve as a pathophysiological model of focal brain injury and/or neurodegenerative disorders.

Optimization of ultraviolet irradiation of Clarias gariepinus (Burchell, 1822) eggs for androgen production

Zygote ◽  
2021 ◽  
pp. 1-6
Author(s):  
Victor Tosin Okomoda ◽  
Haziqah Jumahat Nursyaza ◽  
Ijabo Oga Samuel ◽  
Anuar Hassan ◽  
Abraham Sunday Oladimeji ◽  
...  
Keyword(s):  
Survival Rate ◽  
Uv Irradiation ◽  
Uv Light ◽  
Clarias Gariepinus ◽  
African Catfish ◽  
Chromosome Counting ◽  
Complete Inactivation ◽  
Cell Cleavage ◽  
Optimal Protocol ◽  
Prolonged Duration

Summary The optimum distance and duration of ultraviolet (UV) irradiation for the complete inactivation of African catfish Clarias gariepinus egg nucleus was investigated in this study. The UV light was suspended above the unfertilized eggs at four distances (5, 10, 20 and 30 cm) and for five durations (1, 2, 3, 4 and 5 min). Then, the irradiated eggs were activated with sperm from diploid C. gariepinus and cold shocked at 5°C for 5 min just moments before cell cleavage. Ploidy analysis was performed using karyotype chromosome counting. The results obtained suggested that the further the distance, the better the hatchability rate, however prolonged duration seemed to significantly reduced hatchability. All treatments with surviving progenies at the end of the study showed evidence of successfully diploid gynogen (2n = 56) induction at different percentages. However, the optimal protocol that gave a moderately high hatchability/survival rate and completely induced gynogens was exposure of the eggs to UV irradiation at 20 cm for 1 min. It was concluded that the distance and duration of UV irradiation affects gynogenetic induction in African catfish C. gariepinus.

FC 122BONE DENSITOMETRY IN RENAL TRANSPLANTED PATIENTS

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Ana Carina Ferreira ◽  
Marco Mendes ◽  
Cecília Silva ◽  
Patrícia Cotovio ◽  
Inês Aires ◽  
...  
Keyword(s):  
Bone Densitometry ◽  
Bone Disease ◽  
Bone Biopsy ◽  
Bone Volume ◽  
Categorical Variables ◽  
Good Tool ◽  
X Ray ◽  
Normal Bone ◽  
Dialysis Vintage ◽  
Significant Difference

Abstract Background and Aims Renal transplant and associated immunosuppression can influence bone volume. The aim of this study was to analyze the relations between bone biopsy data and levels of bone-related molecules [phosphorus (Pi), Calcium (Ca), Magnesium (Mg), parathyroid hormone (PTH), bone alkaline phosphatase (bAP), calcitonin, vitamin D (vitD), alpha-klotho, fibroblast grow factor (FGF) 23, sclerostin], obtained 1-year after transplantation with bone densitometry findings in the same time point in renal transplanted patients. Method We performed a prospective cohort study of a consecutive sample of de novo single renal transplanted patients in our unit. At inclusion, demographic, clinical and transplant-related data were collected, X-ray of the pelvis and hands (Adragão score) and echocardiographic findings were recorded. All patients were submitted to a laboratorial evaluation and a bone biopsy at baseline. Patients were followed for 12 months, after which performed laboratorial evaluation, 2nd bone biopsy, echocardiogram, X-ray of pelvis and hands, bone densitometry (DXA) and non-contrast cardiac CT. For this report we use the information of the 2nd analysis: laboratorial information, bone histology information, as well the densitometry evaluation. Continuous variables were presented as medians and categorical variables as frequencies. Associations between variables were performed using Wilcoxon rank-sum test, Fisher exact test, Kruskal Wallis rank test or Spearman correlation test. Multivariate analysis was performed using linear regression models. STATA software was used and p < 0.05 was considered statistically significant. Results We recruited 84 patients and, at the end of 12 months, we performed a 2nd evaluation in 69 patients. Median age 53 years, 48 men, 53 caucasian (78.8%), median BMI 24.6, median dialysis vintage 55 months. Patients had a median cumulative steroid dose of 5692.5 mg. Analyzing bone biopsies, we found that 28 patients had adynamic bone disease; 6 had hyperparathyroid bone disease; 2 had osteomalacia and 3 other abnormal mineralization; 8 patients presented only with osteoporosis. There was no significant difference between bone volume / total volume pre transplant (18%) and 1 year after transplantation (19%). Using DXA technique, 14 patients were classified has having osteoporosis, and all those had low volume at the bone biopsy. Nevertheless, in 4 patients low bone turnover was also present. The positive predictive value dropped from 100% to 57%, if we add the other abnormalities of bone, in addiction to the volume. DXA exam wasn’t a good tool to detect a normal bone volume, as the negative predicted value dropped from 78% (normal volume, irrespective of turnover and mineralization) to 37% (normal bone biopsy). Nevertheless, overall bone volume assessed by a bone biopsy correlated well with densitometry findings. Conclusion DXA exam isn’t a good tool to identify the bone quality. Nevertheless, once osteoporosis is detected the probability of the patient having low bone volume is high, but we still need a bone biopsy in order to exclude mineralization or turnover deviations.

Abstract 17145: Mitral Leaflet Growth and its Relationship with Functional Mitral Regurgitation in Non-ischemic Left Ventricular Systolic Dysfunction

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Yu Kang ◽  
Xiao-Jing Chen ◽  
Qing Zhang ◽  
Xiao-Ling Sun ◽  
Yu-Chen Chen ◽  
...  
Keyword(s):  
Mitral Regurgitation ◽  
Left Ventricular Systolic Dysfunction ◽  
Systolic Dysfunction ◽  
Normal Subjects ◽  
Left Ventricular ◽  
Area Ratio ◽  
Functional Mitral Regurgitation ◽  
Mitral Leaflet ◽  
Significant Difference ◽  
Annular Dilation

Backgrounds: Recent studies evidenced growth of the mitral leaflet (ML) in patients with functional mitral regurgitation (FMR), casting doubt on the traditional understanding of FMR. The aim of this study was to explore whether growth of ML occurs in patients with non-ischemic left ventricular (LV) systolic dysfunction and to examine whether there was any relationship between the growth of ML and the development of FMR. Methods: Echocardiographic examination was performed in 3 groups of patients: patients with non-ischemic LV systolic dysfunction [LV ejection fraction (EF) <50%] and significant FMR (MR jet area ratio≥20%) (group1, n=40), patients with non-ischemic LV systolic dysfunction but no significant FMR (MR jet area ratio <20%) (group2, n=30), and normal subjects (group3, n=40). The lengths of the anterior (AML) and posterior (PML) mitral leaflets as well as the anterior-posterior mitral annular dimension (MAD) were measured to reflect the degree of ML growth and mitral annular dilation. The ratio of AML and PML to MAD (AML: MAD, PML: MAD) were calculated respectively to assess the adequacy of ML growth in the context of mitral annular dilation. Results: The AML, PML, and the MAD were all increased in patients with LV systolic dysfunction (group1 and group2) compared with normal subjects (group3). In patients with LV systolic dysfunction, both PML and MAD were further increased in group1 compared with group2. However, AML showed no significant difference between the 2 groups. As a result, PML:MAD showed no significant difference between group1 and group2, while AML:MAD was significantly decreased in group1 compared with group2 (Table 1). Conclusion: Mitral leaflet growth occurs in patients with non-ischemic LV systolic dysfunction. Insufficient growth of the anterior mitral leaflet relative to dilated mitral annulus is associated with the development of significant FMR.

scholarly journals Modification of Cassava Starch Using Lactic Acid Hydrolysis in The Rotary-UV Dryer to Improve Physichocemical Properties

2018 ◽  
Vol 156 ◽  
pp. 01018 ◽  
Author(s):  
Siswo Sumardiono ◽  
Bakti Jos ◽  
Denny Firmansyah ◽  
Rahmi Hidayatunajah ◽  
Isti Pudjihastuti
Keyword(s):  
Lactic Acid ◽  
Acid Hydrolysis ◽  
Wheat Flour ◽  
Uv Light ◽  
Import Substitution ◽  
Cassava Starch ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Modified Starch ◽  
Significant Difference

Food security should be supported in an effort to utilize local products into import substitution products. Cassava starch has the potential to be developed into semi-finished products in the form of flour or starch which does not contain gluten but can inflate large baking process, potentially as a substitute for wheat flour-the main ingredient for making bread. The characteristic of the starch is influenced by the type of starch composition and structure. Natural starch has physicochemical properties i.e. a long time cooking and pasta formed hard. These constraints allow us to modify cassava starch by a combination of lactic acid hydrolysis and drying with rotary UV system. Modified cassava starch is expected to be used as a substitute for wheat flour. The aim of the research which is a combination of lactic acid hydrolysis and drying using a rotary UV system is to examine the optimum operating conditions in the drying process of starch hydrolysis with parameter the physicochemical and rheological properties of modified cassava starch. The initial process study is to hydrolyze cassava starch using lactic acid. Furthermore, hydrolyzed cassava starch is then dried using UV light in the rotary dryers system. There are a variety of changing variables, i.e. time of irradiation cassava starch-lactic acid hydrolysis products in the rotary UV light and air drying temperature. The research results show that modified starch has a better characteristic than the natural starch. From the analysis, the best point of swelling power, solubility and baking expansion is consequently 15.62 g/g; 24.19 %; 2.21 ml/gr. The FTIR result shows that there is no significant difference of the chemical structure because the starch modification only change the physical characteristics. From the SEM analysis, we can know that the size of the starch’s granule changes between the natural starch and the modified starch..

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