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1.
BMC Med Educ ; 24(1): 754, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38997722

ABSTRACT

INTRODUCTION: Achieving integration in medical curricula without redundancy in basic medical sciences disciplines is a substantial challenge. Introducing co-teaching in such curricula with active inter-disciplinary participation is believed to best utilize the teaching and learning time for instructors and students, to motivate the students, and to provide a more robust base for bridging the gap between basic and clinical medical sciences in medical schools. Additionally, including more than one student-centered activity in one session is expected to increase the students' involvement and improve the retention of knowledge. Our study aims at minimizing redundancy and improving the students' motivation in learning the topic "insulin-glucose regulation" during the Endocrine and Metabolism module taught to year three students at Galala University, Faculty of Medicine in Egypt. METHODS: The authors designed a 3-hr co-teaching integrated session with 3 basic medical sciences aimed to explain the clinical terms including online accessed pre/post-tests, small student groups-created pre/post-session MCQ, with co-sharing of students in the introduction of scientific materials. RESULTS: The students' scores in the post-test showed that they gained more knowledge compared to before. Interestingly, there was only an improvement in the students' performance in generating questions before and after the session, as well as in the integrated question in the end-of-semester exam, we suggest implementing this approach in other topics and modules in medical schools. It would also be favorable to follow up with the students taught using this approach and those taught differently to assess the effectiveness of this approach in a controlled manner. CONCLUSION: Integrated sessions effectively increase student awareness of medical concepts and reduce redundancy in basic medical sciences. This approach exposes students to a more comprehensive understanding of the subject matter, improving their comprehension and retention. It is a valuable method for educators and instructors seeking to enhance their students' learning experience in the field of medical sciences.


Subject(s)
Curriculum , Education, Medical, Undergraduate , Students, Medical , Humans , Egypt , Students, Medical/psychology , Educational Measurement , Teaching , Schools, Medical
2.
J Cosmet Dermatol ; 23(5): 1905-1911, 2024 May.
Article in English | MEDLINE | ID: mdl-38299446

ABSTRACT

BACKGROUND: Psoriasis is an autoimmune disease which has an effect on the joints and skin. Tumor Necrosis Factor-Like Weak Inducer of Apoptosis (TWEAK) is a multi-functional cytokine which regulates the cellular processes and has been related to a variation of conditions. OBJECTIVES: To measure the level of serum TWEAK in psoriatic diseased persons and its relationship to the PASI score pre- and post-therapy with narrowband ultraviolet B phototherapy (NB-UVB) and methotrexate (MTX). METHODS: This randomized controlled trial was conducted on 40 patients and 20 healthy persons as controls. Patient Group was randomly subdivided to two groups. The 1st group consisted of 20 patients who received NB-UVB treatment. The 2nd group included 20 MTX-treated candidates. Blood samples were drawn from patients in order to detect serum TWEAK levels using ELISA. The research was registered on Clinical Trials Registration: RCT approval numbers: NCT0481191. RESULTS: The mean PASI score percent improvement after 12 weeks of treatment was higher in the MTX group (90%) than NB-UVB group (60%). The serum TWEAK level at baseline was 60.47 ± 12.6 pg/mL in NB-UVB group and 54.69 ± 21.7 pg/mL in MTX group which reduced to 24.93 ± 17.6 pg/mL and 32.13 ± 23.6 pg/mL, respectively (p < 0.001), after 12 weeks of treatment. There was a positive correlation between the serum levels of TWEAK and severity of PASI score (r = 0.399, p = 0.014). CONCLUSION: TWEAK grades in psoriasis are substantially higher than in controls. TWEAK levels were dramatically reduced during NB-UVB and MTX treatment. TWEAK may have a potential sign for psoriasis diagnosis and prognosis.


Subject(s)
Cytokine TWEAK , Methotrexate , Psoriasis , Ultraviolet Therapy , Humans , Psoriasis/blood , Psoriasis/radiotherapy , Psoriasis/therapy , Psoriasis/drug therapy , Psoriasis/diagnosis , Cytokine TWEAK/blood , Methotrexate/administration & dosage , Methotrexate/therapeutic use , Ultraviolet Therapy/methods , Female , Male , Adult , Middle Aged , Combined Modality Therapy , Dermatologic Agents/therapeutic use , Dermatologic Agents/administration & dosage , Severity of Illness Index , Treatment Outcome , Young Adult
3.
Int Immunopharmacol ; 128: 111533, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38271813

ABSTRACT

BACKGROUND: Treatment of diabetic neuropathic pain does not change the natural history of neuropathy. Improved glycemic control is the recommended treatment in these cases, given that no specific treatment for the underlying nerve damage is available, so far. In the present study, the potential neuroprotective effect of pentoxifylline in streptozotocin (50 mg/kg) induced diabetic neuropathy in rats was investigated. METHODS: Pentoxifylline was administered at doses equivalent to 50, 100 & 200 mg/kg, in drinking water, starting one week after streptozotocin injection and for 7 weeks. Mechanical allodynia, body weight and blood glucose level were assessed weekly. Epidermal thickness of the footpad skin, and neuroinflammation and vascular alterations markers were assessed. RESULTS: Tactile allodynia was less in rats that received pentoxifylline at doses of 100 and 200 mg/kg (60 % mechanical threshold increased by 48 % and 60 %, respectively). The decrease in epidermal thickness of footpad skin was almost completely prevented by the same doses. This was associated with a decrease in spinal tumor necrosis factor alpha (TNFα) and nuclear factor kappa B levels and a decrease in microglial ionized calcium binding adaptor molecule 1 immunoreactivity, compared to the control diabetic group. In sciatic nerve, there was decrease in TNF-α and vascular endothelial growth factor levels and intercellular adhesion molecule immunoreactivity. CONCLUSION: Pentoxifylline showed a neuroprotective effect in streptozotocin-induced diabetic neuropathy, which was associated with a suppression of both the inflammatory and vascular pathogenic pathways that was not associated with a hypoglycemic effect. Thus, it may represent a potential neuroprotective drug for diabetics.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Neuropathies , Neuroprotective Agents , Pentoxifylline , Rats , Animals , Diabetic Neuropathies/drug therapy , Pentoxifylline/therapeutic use , Neuroprotective Agents/therapeutic use , Streptozocin , Vascular Endothelial Growth Factor A , Diabetes Mellitus, Experimental/drug therapy , Hyperalgesia/drug therapy , Tumor Necrosis Factor-alpha
4.
Clin Cosmet Investig Dermatol ; 16: 3241-3248, 2023.
Article in English | MEDLINE | ID: mdl-37965101

ABSTRACT

Background: In the entire world, acne vulgaris (AV) is the most prevalent skin condition. Approximately 9.4% of people worldwide have acne vulgaris. This study compared the blood levels of chitinase 3-like protein 1 (YKL-40) in acne vulgaris patients before and after oral isotretinoin therapy. Patients and Methods: The design of the study was cross-sectional case-control. Forty patients with moderate to severe acne vulgaris and twenty healthy participants participated in this study. Using the Global Acne Grading System (GAGS) score, patients with acne vulgaris were evaluated both before and after concluding their treatment. Using the enzyme-linked immunosorbent assay (ELISA), the serum levels of YKL-40 were measured before and after oral isotretinoin therapy in healthy controls and acne patients. Results: Patients with acne vulgaris had considerably greater serum levels of YKL-40 than healthy control subjects (p 0.001) did. After three months of oral isotretinoin medication, the GAGS score and blood levels of YKL-40 in acne vulgaris patients both significantly decreased. Conclusion: The conclusion of this study was that reducing the blood levels of YKL-40 and the GAGS score in patients with acne vulgaris who took oral isotretinoin for three months was a crucial strategy.

5.
BMC Cardiovasc Disord ; 23(1): 392, 2023 08 09.
Article in English | MEDLINE | ID: mdl-37559011

ABSTRACT

BACKGROUND: Minimally invasive approaches like mini-thoracotomy and mini-sternotomy for Aortic Valve Replacement (AVR) showed impressive outcomes. However, their advantages for obese patients are questionable. We aimed in this network meta-analysis to compare three surgical approaches: Full sternotomy (FS), Mini-sternotomy (MS), and Mini-thoracotomy (MT) for obese patients undergoing AVR. METHODS: We followed the PRISMA extension for this network meta-analysis. PubMed/Medline, Scopus, Web of Science, and Cochrane searched through March 2023 for relevant articles. The analysis was performed using R version 4.2.3. RESULTS: Out of 344, 8 articles met the criteria with 1392 patients. The main outcomes assessed were perioperative mortality, re-exploration, atrial fibrillation, renal failure, ICU stay, hospital stay, cross-clamp time, and bypass time. In favor of MS, the length of ICU stay and hospital stay was significantly lower than for FS [MD -0.84, 95%CI (-1.26; -0.43)], and [MD -2.56, 95%CI (-3.90; -1.22)], respectively. Regarding peri-operative mortality, FS showed a significantly higher risk compared to MS [RR 2.28, 95%CI (1.01;5.16)]. Also, patients who underwent minimally invasive approaches; MT and MS, required less need of re-exploration compared to FS [RR 0.10, 95%CI (0.02;0.45)], and [RR 0.33, 95%CI (0.14;0.79)], respectively. However, Intraoperative timings; including aortic cross-clamp, and cardiopulmonary bypass time, were significantly lower with FS than for MS [MD -9.16, 95%CI (-1.88; -16.45)], [MD -9.61, 95%CI (-18.64; -0.59)], respectively. CONCLUSION: Our network meta-analysis shows that minimally invasive approaches offer some advantages for obese patients undergoing AVR over full sternotomy. Suggesting that these approaches might be considered more beneficial alternatives for obese patients undergoing AVR.


Subject(s)
Aortic Valve , Heart Valve Prosthesis Implantation , Humans , Aortic Valve/diagnostic imaging , Aortic Valve/surgery , Network Meta-Analysis , Heart Valve Prosthesis Implantation/adverse effects , Treatment Outcome , Minimally Invasive Surgical Procedures/adverse effects , Sternotomy/adverse effects , Obesity/complications , Obesity/diagnosis , Obesity/surgery , Retrospective Studies
6.
Article in English | MEDLINE | ID: mdl-36795867

ABSTRACT

INTRODUCTION: Extremity injuries are a leading cause of morbidity in low- and middle-income countries (LMICs), often resulting in marked short-term and long-term disabilities. Most of the existing knowledge on these injuries originates from hospital-based studies; however, poor access to health care in LMICs limits these data because of inherent selection bias. This subanalysis of a larger population-level cross-sectional study in the Southwest Region of Cameroon aims to determine patterns of limb injury, treatment-seeking behaviors, and predictors of disability. METHODS: Households were surveyed in 2017 on injuries and subsequent disability sustained over the previous 12 months using a three-stage cluster sampling framework. Subgroups were compared using the chi square, Fisher exact, analysis of variance, Wald, and Wilcoxon rank-sum tests. Logarithmic models were used to identify predictors of disability. RESULTS: Of 8,065 subjects, 335 persons (4.2%) sustained 363 isolated limb injuries. Over half of the isolated limb injuries (55.7%) were open wounds while 9.6% were fractures. Isolated limb injuries most commonly occurred in younger men and resulted from falls (24.3%) and road traffic injuries (23.5%). High rates of disability were reported, with 39% reporting difficulty with activities of daily living. Compared with individuals with other types of limb injuries, those with fractures were six times more likely to seek a traditional healer first for care (40% versus 6.7%), 5.3 times (95% CI, 1.21 to 23.42) more likely to have any level of disability after adjustment for injury mechanism, and 2.3 times more likely to have difficulty paying for food or rent (54.8% versus 23.7%). DISCUSSION: Most traumatic injuries sustained in LMICs involve limb injuries and often result in high levels of disability that affect individuals during their most productive years. Improved access to care and injury control measures, such as road safety training and improvements to transportation and trauma response infrastructure, are needed to reduce these injuries.


Subject(s)
Activities of Daily Living , Fractures, Bone , Male , Humans , Cameroon/epidemiology , Cross-Sectional Studies , Accidents, Traffic
8.
Article in English | MEDLINE | ID: mdl-35565132

ABSTRACT

Vaccine hesitancy (VH) is defined as a delayed in acceptance or refusal of vaccines despite availability of vaccination services. This multinational study examined user interaction with social media about COVID-19 vaccination. The study analyzed social media comments in 24 countries from five continents. In total, 5856 responses were analyzed; 83.5% of comments were from Facebook, while 16.5% were from Twitter. In Facebook, the overall vaccine acceptance was 40.3%; the lowest acceptance rates were evident in Jordan (8.5%), Oman (15.0%), Senegal (20.0%) and Morocco (20.7%) and the continental acceptance rate was the lowest in North America 22.6%. In Twitter, the overall acceptance rate was (41.5%); the lowest acceptance rate was found in Oman (14.3%), followed by USA (20.5%), and UK (23.3%) and the continental acceptance rate was the lowest in North America (20.5%), and Europe (29.7%). The differences in vaccine acceptance across countries and continents in Facebook and Twitter were statistically significant. Regarding the tone of the comments, in Facebook, countries that had the highest number of serious tone comments were Sweden (90.9%), USA (61.3%), and Thailand (58.8%). At continent level, serious comments were the highest in Asia (58.4%), followed by Africa (46.2%) and South America (46.2%). In Twitter, the highest serious tone was reported in Egypt (72.2%) while at continental level, the highest proportion of serious comments was observed in Asia (59.7%), followed by Europe (46.5%). The differences in tone across countries and continents in Facebook and Twitter and were statistically significant. There was a significant association between the tone and the position of comments. We concluded that the overall vaccine acceptance in social media was relatively low and varied across the studied countries and continents. Consequently, more in-depth studies are required to address causes of such VH and combat infodemics.


Subject(s)
COVID-19 , Social Media , Vaccines , COVID-19/prevention & control , COVID-19 Vaccines , Caffeine , Humans , Morocco , Thailand , Vaccination
9.
Adv Med Educ Pract ; 13: 427-441, 2022.
Article in English | MEDLINE | ID: mdl-35521292

ABSTRACT

Purpose: This evaluation draws evidence on the outcome of learning and teaching courses that were offered to a number of teaching staff (referred to as trainers) of the Academies of Health Sciences, Midwifery Schools and Centre for Continuous Professional Development in Sudan. Methods: The evaluation was a cross-sectional, institution-based study conducted from October 2017 to January 2018 involving qualitative design. It consisted of direct observations of teaching, focus group discussions with students and semi-structured interviews with managers of teaching institutions. Results: The findings of direct observations revealed that the learning and teaching course has positive effects on the trainers' ability to have clear, well-stated learning objectives; their presentation skills; and their use of different teaching methods. Moreover, the observations showed that trainers who attended the learning and teaching course now encourage the students to ask questions and are providing them with timely feedback about their learning. As students were the main beneficiaries for improved teaching, focus group discussions have shown that students were generally satisfied with trainers' performance regarding the stated learning outcomes, curricula design, use of a range of teaching methods and assessment methods. During in-depth interviews, managers of training institutions expressed satisfaction with the trainers' performance regarding the development of training materials, learners' assessment, supervision, and evaluation of training. Conclusion: Short courses on teaching and learning were a valuable investment for trainers, students, and the overall performance of health sciences training institutions. The evaluation revealed that trainers were able to apply what they have learnt. Moreover, students and managers noticed improvement in the performance of trainers in teaching, course delivery and assessment. It is recommended to expand, cascade and institutionalize the short courses on learning and teaching to all states to improve the capabilities of trainers, which would eventually contribute to the production of competent allied health professions in Sudan.

10.
Rep Biochem Mol Biol ; 11(3): 367-376, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36718302

ABSTRACT

Background: Psoriasis is a chronic inflammatory immune mediated disease arising from interaction between genetic risk variants and the environment. Maternally expressed gene3 (MEG3) is a long noncoding RNA (lncRNA) known for gene transcription regulation and inhibiting proliferation. MEG3 competes with microRNA (miRNA-21) influencing cell proliferation and apoptosis balance. Endoplasmic reticulum (ER) stress proteins promote cell survival via unfolded protein response (UPR) influenced by MEG3. We aimed to detect the possible role of MEG3, miRNA-21 and ER stress proteins in pathogenesis of psoriasis vulgaris. Methods: Human GRP78, ATF6, caspase3 tissue levels were assayed by Enzyme Linked Immunosorbent Assay (ELISA). Assessment of long non-coding MEG3 and miRNA 21 expressions was done by quantitative real time polymerase chain reaction (qRT-PCR). Results: Expression of MEG3 was significantly downregulated, while miRNA-21 was remarkably upregulated, ER stress proteins GRP78, ATF6, and caspase 3 all showed low levels in homogenized psoriatic lesions when compared to normal skin. miRNA 21 and MEG3 were identified as possible diagnostic markers for psoriasis vulgaris. Discussion: MEG3 is barely expressed in psoriatic lesions while miRNA-21 expression is remarkably elevated but when correlated to each other there was unexpected positive correlation. MEG3 and miRNA-21 were identified as possible diagnostic markers for psoriasis. Undifferentiated psoriatic lesions have very weak UPR.

11.
Curr Pharm Biotechnol ; 21(14): 1528-1538, 2020.
Article in English | MEDLINE | ID: mdl-32188380

ABSTRACT

BACKGROUND: In Saudi Arabia, the incidence and mortality rates of breast cancer are high. Although current treatments are effective, breast cancer cells develop resistance to these treatments. Numerous studies have demonstrated that active compounds in plant extracts, such as the phenolic compound Rosmarinic Acid (RA), exert anti-cancer effects. OBJECTIVE: We investigated the anticancer properties of methanolic crude extracts of seedlings and calli of Rosmarinus officinalis and Coleus hybridus, two Lamiaceae species. METHODS: MCF-7 human breast cancer cells were treated with methanolic crude extracts obtained from plant calli and seedlings generated in vitro, and cell proliferation was evaluated. Transcriptional profiling of the seedling and callus tissues was also conducted. RESULTS: The mRNA expression levels of RA genes were higher in C. hybridus seedlings than in R. officinalis seedlings, as well as in C. hybridus calli than in R. officinalis calli, except for TAT and C4H. In addition, seedling and callus extracts of both R. officinalis and C. hybridus showed anti-proliferative effects against MCF-7 cells after 24 or 48 h of treatment. DISCUSSION: At a low concentration of 10 µg/mL, C. hybridus calli and seedling extracts showed the most significant anti-proliferative effects after 24 and 48 h of exposure (p < 0.01); controls (doxorubicin) also showed significant inhibition, but lesser than that observed with C. hybridus (p < 0.05). Results with R. officinalis callus and seedling extracts did not significantly differ from those with untreated cells. CONCLUSION: Methanolic extracts of R. officinalis and C. hybridus are potentially valuable options for breast cancer treatment.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cell Proliferation/drug effects , Cinnamates/pharmacology , Coleus/chemistry , Depsides/pharmacology , Plant Extracts/pharmacology , Rosmarinus/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Survival , Cinnamates/isolation & purification , Depsides/isolation & purification , Dose-Response Relationship, Drug , Humans , MCF-7 Cells , Plant Extracts/isolation & purification , Plant Shoots/chemistry , Seedlings/chemistry , Rosmarinic Acid
12.
Curr Opin Biotechnol ; 63: 16-25, 2020 06.
Article in English | MEDLINE | ID: mdl-31809974

ABSTRACT

RNA has grown in biological importance as the discovery of its many functional roles in the cellular machinery has revealed the potential for targeting it to disrupt cancer pathways. RNA structure underlies its functionality and suitability as a nanoparticle building material. Advances in modelling methods have been achieved by the recognition of common structural motifs in natural RNA molecules that can be employed in the prediction of new structures based on sequence information and in design of functional nanostructures. Ligand docking prediction programs and RNA dynamics adds an important and non-trivial aspect to the modeling and characterization of the RNA structures. This short review introduces the issues involved in RNA structure prediction and modeling, dynamics of RNA structures, the influence of ligands on the structure and the dynamics, and ways to incorporate this information in the design of RNA-based nanostructures.


Subject(s)
Nanostructures , RNA , Ligands , RNA/genetics
13.
J Surg Res ; 232: 578-586, 2018 12.
Article in English | MEDLINE | ID: mdl-30463777

ABSTRACT

BACKGROUND: Injuries are a leading cause of death and disability worldwide. Developing countries account for 90% of injury-related deaths globally. Trauma audit filters can facilitate trauma quality improvement initiatives and reduce the injury burden. Little is known about context-appropriate trauma audit filters for developing countries such as Cameroon. This study aimed to (1) develop context-appropriate trauma audit filters for the setting of a regional referral hospital in Cameroon and (2) to assess the barriers and facilitators to their implementation. METHODS: Feasible audit filters were identified by a panel of Cameroonian surgeons using the Delphi technique. A Likert scale (1 to 5, with 5 as "Most Useful") was used to rank the filters for utility in a regional referral hospital setting, analyzed using the median and interquartile range. Semistructured interviews were conducted with 16 health care providers from three hospital facilities to explore their perceptions of supervision and support they receive from hospital administration, availability of resources, their work environment, and potential concerns and impacts of trauma audit filters. Interviews were coded and thematically analyzed. RESULTS: Within a panel of seven surgeons, 23 of 40 trauma audit filter variables met majority consensus criteria. Twenty-one of these, comprising mostly of primary survey and basic resuscitation techniques, had a median score of ≥4. Filters meeting consensus include, but are not limited to, vitals obtained, breathing assessment made, and two large bore intravenous established within 15 min of arrival; patient with open fracture receives intravenous antimicrobials within 1 h of arrival; patients with suspected spine injury are immobilized and given X-ray. The provider interviews revealed that the barriers to providing quality care were limited human and material resources and patients' inability to pay. Regular staff training in trauma care and the belief that trauma audit filters would potentially streamline work practices and improve the quality of care were cited as promoters of successful implementation. CONCLUSIONS: Primary survey and basic resuscitative techniques are key elements of context-appropriate audit filters in Cameroon. Such audit filters may not be costly, require complex infrastructure, or equipment that exceed the site's capabilities. Proper staff orientation and participation in the use of trauma audit filters, as quality improvement tools, are key to local buy-in and implementation success.


Subject(s)
Medical Audit , Quality Improvement , Referral and Consultation , Wounds and Injuries/therapy , Adult , Aged , Cameroon , Delphi Technique , Female , Humans , Male , Middle Aged
14.
J Clin Pediatr Dent ; 41(2): 120-125, 2017.
Article in English | MEDLINE | ID: mdl-28288289

ABSTRACT

AIM: To assess the effect of four different children's drinks on color stability of resin dental composites. STUDY DESIGN: A total of one hundred and twenty specimens were prepared from Grandio SO, Filtek Z350 XT and Filtek Z250 XT (forty specimens each). Specimens were thermocycled, then each group was further subdivided into four subgroups (n=10) according to the immersion media which were chocolate milk, mango juice, orange fizzy drink, and water (control). The initial color parameters of each specimen were recorded before immersion (baseline) and color change values were recorded three and seven days after immersion in each solution using a digital spectrophotometer. Atomic force microscope was used to measure the surface roughness in randomly selected samples after one week immersion in children's drinks. RESULTS: All the children's drinks produced color changes in the examined resin dental composites, yet there was no statistical significant difference between the effects of tested drinks on the color changes (mean ΔE) of the three different dental composites (P>0.05). CONCLUSIONS: All tested children's drinks caused clinically unacceptable color changes of the tested resin dental composites. Immersion in chocolate milk and orange fizzy led to the highest color changes in the tested resin dental composites.


Subject(s)
Beverages , Composite Resins/chemistry , Color , Humans , Spectrophotometry , Surface Properties
15.
Clin Oral Implants Res ; 25(2): e1-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23173838

ABSTRACT

OBJECTIVES: This study was conducted to create nanostructured surface titanium implants by anodic oxidation process aiming to bring out bioactivity and to assess the resultant bioactivity both in vitro and in vivo. MATERIALS AND METHODS: An economic protocol was used to apply anodic spark discharge and create surface nanoporosities on grade II commercially pure titanium (cpTi). The in vitro investigation included morphology, surface chemical analysis, roughness and crystalline structure of titanium oxide (TiO2) film prepared. Assessment of the bioactivity was carried out by immersing the specimens in simulate body fluid (SBF) and investigating the surface-deposited layer. The in vivo investigation was conducted by surgically placing the anodized implants into rabbits tibia for different healing periods. Then biomechanical evaluation was performed to verify the effect of treatments on the interface resistance to shear force. Routine histological analysis was performed to evaluate the bone tissue reactions to anodized implants. RESULTS: Anodization of titanium implants produced morphological changes, raised the percentage of oxygen in the TiO2 layer, increased surface area and roughness of implants remarkably, and modified the crystallinity of the film. The in vitro assessments of bioactivity showed that a layer of calcium phosphate was precipitated on the titanium surfaces 7 days after soaking into SBF. The implant-bone interface resistance to shear force was enhanced at 2-week healing period. This was confirmed by histological findings. CONCLUSION: Nanostructured surface titanium implants could be prepared by anodic oxidation with resultant accelerated bioactivity that may be recommended for early loading.


Subject(s)
Coated Materials, Biocompatible/chemistry , Dental Implants , Titanium/chemistry , Animals , Implants, Experimental , Male , Materials Testing , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Nanostructures , Oxidation-Reduction , Rabbits , Surface Properties , Tibia/surgery , X-Ray Diffraction
16.
J Environ Radioact ; 84(1): 51-64, 2005.
Article in English | MEDLINE | ID: mdl-15951070

ABSTRACT

Samples of phosphate fertilizers and farm soils, taken to a depth of up to 30 cm in cultivated land, were collected over the Qena governorate, Upper Egypt. Activity concentration of background radionuclides such as (226)Ra, (232)Th and (40)K of these samples were determined by gamma-ray spectrometry. The results show that these radionuclides were present in concentrations of 366+/-10.5, 66.7+/-7.3 and 4+/-2.6 Bq/kg for phosphate fertilizers. For farm soil and Nile island's soil the corresponding values were 13.7+/-7, 12.3+/-4.6, 1233+/-646 and 11.9+/-6.7, 10.5+/-6.1, 1636+/-417 Bq/kg, respectively. The radium equivalent activity (Ra(eq)), the representative level index, I(gamma r), and absorbed dose in air for all samples were calculated. The data were discussed and compared with those given in the literature.


Subject(s)
Environmental Exposure/statistics & numerical data , Fertilizers/analysis , Potassium Radioisotopes/analysis , Radium/analysis , Soil/analysis , Thorium/analysis , Egypt , Radiometry , Spectrometry, Gamma
17.
J Environ Radioact ; 83(1): 91-9, 2005.
Article in English | MEDLINE | ID: mdl-15935911

ABSTRACT

Building materials cause direct radiation exposure because of their radium, thorium and potassium content. In this paper, samples of commonly used building materials (bricks, cement, gypsum, ceramics, marble, limestone and granite) in Qena city, Upper Egypt have been collected randomly over the city. The samples were tested for their radioactivity contents by using gamma spectroscopic measurements. The results show that the highest mean value of (226)Ra activity is 205+/-83 Bqkg(-1) measured in marble. The corresponding value of (232)Th is 118+/-14 Bqkg(-1) measured in granite. For (40)K this value is (8.7+/-3.9)x10(2) Bqkg(-1) measured in marble. The average concentrations of the three radionuclides in the different building materials are 116+/-54, 64+/-34 and (4.8+/-2.2)x10(2) Bqkg(-1) for (226)Ra, (232)Th and (40)K, respectively. Radium equivalent activities and various hazard indices were also calculated to assess the radiation hazard. The maximum mean of radium equivalent activity Ra(eq) is 436+/-199 Bqkg(-1) calculated in marble. The highest radioactivity level and dose rate in air from these materials were calculated in marble.


Subject(s)
Construction Materials/analysis , Environmental Exposure/analysis , Potassium Radioisotopes/analysis , Radium/analysis , Thorium/analysis , Cities , Egypt , Radiation Monitoring , Risk Assessment , Sampling Studies , Spectrometry, Gamma
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