• The Journal of Advanced Prosthodontics
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• v.9 no.3
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• pp.217-223
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• 2017

PURPOSE. This study investigated the effects of silver nanoparticle (SN) loading into hydraulic calcium silicate-based Portland cement on its mechanical, antibacterial behavior and biocompatibility as a novel dental bone substitute. MATERIALS AND METHODS. Chemically reduced colloidal SN were combined with Portland cement (PC) by the concentrations of 0 (control), 1.0, 3.0, and 5.0 wt%. The physico-mechanical properties of silver-Portland cement nanocomposites (SPNC) were investigated through X-ray diffraction (XRD), setting time, compressive strength, solubility, and silver ion elution. Antimicrobial properties of SPNC were tested by agar diffusion against Streptococcus mutans and Streptococcus sobrinus. Cytotoxic evaluation for human gingival fibroblast (HGF) was performed by MTS assay. RESULTS. XRD certified that SN was successfully impregnated in PC. SPNC at above 3.0 wt% significantly reduced both initial and final setting times compared to control PC. No statistical differences of the compressive strength values were detected after SN loadings, and solubility rates of SPNC were below 3.0%, which are acceptable by ADA guidelines. Ag ion elutions from SPNC were confirmed with dose-dependence on the concentrations of SN added. SPNC of 5.0 wt% inhibited the growth of Streptococci, whereas no antimicrobial activity was shown in control PC. SPNC revealed no cytotoxic effects to HGF following ISO 10993 (cell viability > 70%). CONCLUSION. Addition of SN promoted the antibacterial activity and favored the bio-mechanical properties of PC; thus, SPNC could be a candidate for the futuristic dental biomaterial. For clinical warrant, further studies including the inhibitory mechanism, in vivo and long-term researches are still required.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2523-2531
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• 2009

Effects of some diacid, diamine and dinitro aromatic compounds on the structure and activity of adenosine deaminase (ADA) were investigated by UV-Vis spectrophotometry in 50 mM phosphate buffer at pH = 7.5 and 27 ${^{\circ}C}$ and molecular docking studies. The results showed that all tested ligands are showing inhibition; five ligands are uncompetitive and other two ligands are mixed of competitive and noncompetetive inhibitors with majority of competitive behavior. For the later case analysis was done based on competitive inhibition. Diacids have larger size and higher inhibition constant ($K_I$) relative to others. A logical correlation between calculated free energy of binding and experimental values was obtained for un-competitive. Experimental and calculated data showed that competitive inhibitors are distributed near the active site of enzyme and form several cluster of ranks, whereas uncompetitive inhibitors bind to the enzyme-substrate complex and distributed far from the active site. Results of structure-activity relationship showed that, larger, more hydrophobe, less spherical and more aromatic ligands have higher inhibition constants.

• Korean Journal of Culture and Social Issue
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• v.15 no.2
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• pp.251-271
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• 2009

This research measured a concept of mobility which is included objective travel behavior as well as psychological and physical mechanism that influenced travel behavior. And then, this research examined the relation between mobility and the quality of life in elderly drivers. In research 1, to evaluate the reliability and validity of "Mobility Questionnaire(MQ)", we tested "MQ" to 207 drivers aged 20 years and older. In research 2, we examined the mobility level of elderly drivers. Also we investigated the influence that mobility of elderly drivers impacts on their quaility of life. we used "MQ", "Psychological Well-Being Questionnaire(PWBQ)" to 91 drivers aged 65 years and older. To factor analysis, MQ consisted of 'Safe Driving Ability(ADA)', 'Travel Increase(TI)', 'Travel Decrease(TD)', 'Social Activity(SA)', and 'Driving Situational Adaptability(DSA)'. The amount and speed of driving of elderly drivers reduced driving behavior than other drivers. Also, elderly drivers negatively assessed their physical abilities for safe driving and felt a low confidence in specific driving situation. On the other hand, elderly drivers take parts in social activity constructively. A review of the relation of mobility and quality of life showed that mobility of elderly drivers had positive correlation with PWB. Specially, 'ADA', 'SA', and 'DSA' had significant correlations with PWB of elderly drivers. The mobility of elderly drivers had an effect on 'Autonomy', 'Environmental mastery', 'Self-acceptance', and 'Positive relations with others'.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.22-29
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• 1996

Background: Abnormalities of the peripheral blood are frequent and varied in patients with miliary tuberculosis. Anemia, leukopenia, thrombocytopenia, pancytopenia, monocytosis, basophilia, eosinophilia and leukemoid reactions have been reported. These abnormalities are more frequent in patients with positive bone marrow study. In this report, we evaluated clinical, hematological and immunological features in patients with miliary tuberculosis in order to know whether difference is existed between "bone marrow biopsy positive group(pathologically proven to miliary tuberculosis)" and "negative group". Method: Clinical evaluation, serum ADA, sIL-2R, and T-lymphocyte subsets were measured in 40 patients with miliary tuberculosis who received bone marrow biopsy. Results: 1) The average age of patients was 39 year-old. There were 23 male and 17 female patients. Associated extrapulmonary tuberculosis are 9 CNS tuberculosis, 6 joint tuberculosis, and 2 tuberculous pleurisy. 2) Sixteen of the 40 patients were positive bone marrow biopsy(60%). 3) Sixteen of the 40 patients(60%) had anemia(11 positive patients: 13 negative patients). Leukopenia occurred in 12 per cent(4:1). Thrombocytopenia was noted in 10%(3:1). 4) The mean value of serum ADA was 83 U/L(90 U/L: 70.6 U/L, p=0.23). 5) The mean activity of Soluble IL-2 receptor was 4,643 pmol/L($6840{\pm}7446\;pmol/L$: $1,897{\pm}1,663\;pmol/L$, p=0.06). 6) In the T lymphocyte subsets, the percent of T-lymphocytes was 64%(62%:73%, p=0.2). In some patients(9), $T_4$ and $T_8$ ratio in BAL fluid($1.97{\pm}1.2$) was higher than that in the peripheral blood($1.16{\pm}0.5$). Conclusion: Bone marrow examination are diagnostic in 60% of cases of miliary tuberculosis. Percents of the total T lymphocyte and helper T cell in BAL are more elevated than in peripheral blood. There was no significant difference in peripheral blood abnormalities and marker of T lymphocyte activation between the bone marrow biopsy positive and negative group.

• Tuberculosis and Respiratory Diseases
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• v.76 no.4
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• pp.175-178
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• 2014

Here, we report a case of pleural paragonimiasis that was confused with tuberculous pleurisy. A 38-year-old man complained of a mild febrile sensation and pleuritic chest pain. Radiologic findings showed right pleural effusion with pleural thickening and subpleural consolidation. Adenosine deaminase (ADA) activity in the pleural effusion was elevated (85.3 IU/L), whereas other examinations for tuberculosis were negative. At this time, the patient started empirical anti-tuberculous treatment. Despite 2 months of treatment, the pleural effusion persisted, and video-assisted thoracoscopic surgery was performed. Finally, the patient was diagnosed with pleural paragonimiasis based on the pathologic findings of chronic granulomatous inflammation containing Paragonimus eggs. This case suggested that pleural paragonimiasis should be considered when pleural effusion and elevated ADA levels are observed.

• Tuberculosis and Respiratory Diseases
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• v.59 no.2
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• pp.186-192
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• 2005

Background : Diagnosis of tuberculous pleurisy is sometimes difficult using conventional diagnostic methods. We have investigated the utility of pleural fluid cell $IFN-{\gamma}$ production assay in the diagnosis of tuberculous pleurisy. Methods : We prospectively performed pleural fluid cell $IFN-{\gamma}$ production assay in 39 patients with tuberculous pleural effusions (TPE) and in 26 patients with nontuberculous pleural effusions (NTPE) (13 malignant pleural effusions and 13 parapneumonic effusions). Pleural fluid cells were cultured in DMEM media and stimulated with purified protein derivatives (PPD), and phytohemagglutinin (PHA) for 24 hr. The amount of $IFN-{\gamma}$ released in the culture supernatant was quantitated by $IFN-{\gamma}$ ELISA assay. We have also measured adenosine deaminase (ADA) activities and $IFN-{\gamma}$ concentrations in the pleural fluid. Results : 1) The pleural fluid levels of ADA activity and $IFN-{\gamma}$ concentrations were significantly higher in TPE than NTPE (p<0.01). 2) $IFN-{\gamma}$ production in TPE cells stimulated by PPD ($755,266{\pm}886,636pg/ml$) was significantly higher than NTPE cells ($3,509{\pm}6,980pg/ml$) (p<0.01). By considering the fact that $IFN-{\gamma}$ concentrations over 10,000 pg/ml is a criteria for the diagnosis of TBE, sensitivity and specificity of the test were 97.4 and 92.3%, respectively. 3) The ratios of $IFN-{\gamma}$ production by the stimulation with PPD and PHA (PPD/PHA) were significantly higher in TPE cells ($59{\pm}85$) than NTPE cells ($5{\pm}18$)(p<0.01). Considering the criteria for the diagnosis of TBE as PPD/PHA ratio over 5, sensitivity and specificity of the test were 76.9 and 92.3%, respectively. Conclusion : Pleural fluid cell $IFN-{\gamma}$ production assay may be useful for the diagnosis of tuberculous pleurisy.

• Molecules and Cells
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• v.20 no.1
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• pp.1-16
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• 2005

The peptidyl transferase center (PTC) is located in a protein free environment, thus confirming that the ribosome is a ribozyme. This arched void has dimensions suitable for accommodating the 3'ends of the A-and the P-site tRNAs, and is situated within a universal sizable symmetry-related region that connects all ribosomal functional centers involved in amino-acid polymerization. The linkage between the elaborate PTC architecture and the A-site tRNA position revealed that the A-to P-site passage of the tRNA 3'end is performed by a rotatory motion, which leads to stereochemistry suitable for peptide bond formation and for substrate mediated catalysis, thus suggesting that the PTC evolved by genefusion. Adjacent to the PTC is the entrance of the protein exit tunnel, shown to play active roles in sequence-specific gating of nascent chains and in responding to cellular signals. This tunnel also provides a site that may be exploited for local co-translational folding and seems to assist in nascent chain trafficking into the hydrophobic space formed by the first bacterial chaperone, the trigger factor. Many antibiotics target ribosomes. Although the ribosome is highly conserved, subtle sequence and/or conformational variations enable drug selectivity, thus facilitating clinical usage. Comparisons of high-resolution structures of complexes of antibiotics bound to ribosomes from eubacteria resembling pathogens, to an archaeon that shares properties with eukaryotes and to its mutant that allows antibiotics binding, demonstrated the unambiguous difference between mere binding and therapeutical effectiveness. The observed variability in antibiotics inhibitory modes, accompanied by the elucidation of the structural basis to antibiotics mechanism justifies expectations for structural based improved properties of existing compounds as well as for the development of novel drugs.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.19-30
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• 2021

Diabetes Mellitus (DM) is one of common chronic diseases leading to severe health complications that may cause death. The disease influences individuals, community, and the government due to the continuous monitoring, lifelong commitment, and the cost of treatment. The World Health Organization (WHO) considers Saudi Arabia as one of the top 10 countries in diabetes prevalence across the world. Since most of the medical services are provided by the government, the cost of the treatment in terms of hospitals and clinical visits and lab tests represents a real burden due to the large scale of the disease. The ability to predict the diabetic status of a patient without the laboratory tests by performing screening based on some personal features can lessen the health and economic burden caused by diabetes alone. The goal of this paper is to investigate the prediction of diabetic and prediabetic patients by considering factors other than the laboratory tests, as required by physicians in general. With the data obtained from local hospitals, medical records were processed to obtain a dataset that classified patients into three classes: diabetic, prediabetic, and non-diabetic. After applying three machine learning algorithms, we established good performance for accuracy, precision, and recall of the models on the dataset. Further analysis was performed on the data to identify important non-laboratory variables related to the patients for diabetes classification. The importance of five variables (gender, physical activity level, hypertension, BMI, and age) from the person's basic health data were investigated to find their contribution to the state of a patient being diabetic, prediabetic or normal. Our analysis presented great agreement with the risk factors of diabetes and prediabetes stated by the American Diabetes Association (ADA) and other health institutions worldwide. We conclude that by performing class-specific analysis of the disease, important factors specific to Saudi population can be identified, whose management can result in controlling the disease. We also provide some recommendations learnt from this research.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.17-24
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• 1999

Background : A sizable percentage of tuberculous pleurisy patients are known to have residual pleural thickening(RPT) despite adequate anti-tuberculous chemotherapy. But, the predictive factors related to the development of RPT is not well known. Therefore, we studied to determine which factors are related to the development of RPT after completion of therapy. Methods: By retrospective review of medical records, fifty-eight patients initially diagnosed as having tuberculous pleurisy between March 1995 and January 1998 were separated into two groups : 27 patients in group 1 had RPT on simple chest radiography, while 31 patients in group 2 had no RPT after 6 month of anti-tuberculous chemotherapy. The clinical characteristics, radiologic findings and pleural fluid findings of the two group were compared at the time of diagnosis and during the course of therapy. Results: 47% of patients had RPT after 6 month of chemotherapy, and RPT was more common in man than in women(54% vs 29%, p=0.092). In group 2 patients, complete resorption of pleural lesion occurred rather late stage of therapy(1-2 month: 26%, 3-4 month: 29%, 5-6 month: 45%). Group 1 patients had increased percentage of loculated pleural lesion(26 % vs 19%) and increased white blood cell and lymphocyte count, lactate dehydrogenase level in pleural fluid ($3527\pm5652$ vs $2467\pm2201$/ml, $2066\pm2022$ vs $1698\pm1835$/ml and $1636\pm1143$ vs $1441\pm923$IU/mL respectively) than group 2 at the time of diagnosis, but statistically insignificant. Duration of symptom prior to treatment, size of pleural effusion, presence of parenchymal lung lesion, level of total protein, glucose and adenosine deaminase(ADA)activity in pleural fluid were similar in both group. Conclusion: 53% of tuberculous pleurisy patients showed slow but complete resorption of pleural lesion after 6 month of chemotherapy. But, no clinical, radiological and pleural fluid findings are predictive for the development of RPT.