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Biomedical subjects

H Erdogan

Publications and source records attributed to H Erdogan.

13 recordsLinked to original sources
PubMed1999

Novel antiinflammatory analgesics: 3-(2-/4-pyridylethyl)-benzoxazolinone and oxazolo[4,5-b]pyridin-2-one derivatives.

Twenty-two new 3-[2-(2-and/or 4-pyridyl)ethyl]benzoxazolinone and oxazolo[4,5-b]pyridin-2-one derivatives have been synthesized by reacting 2- and/or 4-vinylpyridine and appropriate benzoxazolinones and oxazolo[4,5-b]pyridine-2-one. Their chemical structures have been proven by IR. 1H-NMR, 13C-NMR, mass spectroscopy, and elemental analysis. The analgesic activities of these compounds were investigated by a modified Koster's Test. Test results revealed that, at 100 mg/kg dose level, most of the compounds showed significant analgesic activities when compared to aspirin. Therefore the compounds were screened for their antiinflammatory activities using the carrageenan hind paw edema test. Compounds 1, 7, 10, 11, 12, 13, 15, 18, 20, 21 were found more active than indomethacine. In gastric ulceration studies gastrointestinal bleeding was not observed at 100 mg/kg dose level in compounds 1 and 2.

Animals↗
PubMed1999

Ordered subsets algorithms for transmission tomography.

The ordered subsets EM (OSEM) algorithm has enjoyed considerable interest for emission image reconstruction due to its acceleration of the original EM algorithm and ease of programming. The transmission EM reconstruction algorithm converges very slowly and is not used in practice. In this paper, we introduce a simultaneous update algorithm called separable paraboloidal surrogates (SPS) that converges much faster than the transmission EM algorithm. Furthermore, unlike the 'convex algorithm' for transmission tomography, the proposed algorithm is monotonic even with nonzero background counts. We demonstrate that the ordered subsets principle can also be applied to the new SPS algorithm for transmission tomography to accelerate 'convergence', albeit with similar sacrifice of global convergence properties as for OSEM. We implemented and evaluated this ordered subsets transmission (OSTR) algorithm. The results indicate that the OSTR algorithm speeds up the increase in the objective function by roughly the number of subsets in the early iterates when compared to the ordinary SPS algorithm. We compute mean square errors and segmentation errors for different methods and show that OSTR is superior to OSEM applied to the logarithm of the transmission data. However, penalized-likelihood reconstructions yield the best quality images among all other methods tested.

Algorithms↗
PubMed1998

Does immunologic status predict peritonitis in children treated with CAPD?

The purpose of this study was to evaluate whether immunologic status could predict the development of peritonitis in children on continuous ambulatory peritoneal dialysis (CAPD). Twenty-one patients (12 boys, 9 girls) aged 10.1 +/- 4.32 years (range: 23 months to 14 years) were studied. The mean duration of CAPD treatment was 12.88 +/- 6.69 months (range: 2-22 months). Twelve healthy children (mean age 11.5 years) were selected as a control group. Lymphocyte subpopulations (CD3, CD4, CD8, CD19, NK, and IL-2R) were determined by double-color flow cytometry (Becton-Dickinson). Statistical evaluation was made by Student's t-test. CD4 (38.4 +/- 7.1% vs. 28.0 +/- 5.4%), CD4/CD8 ratio (1.30 +/- 0.4 vs. 0.96 +/- 0.3), and B lymphocyte (19.9 +/- 8.9% vs. 12.0 +/- 3.2%) levels were significantly higher in CAPD patients compared with controls. CAPD patients showed significantly lower natural killer (NK) cell values than controls (12.7 +/- 7.0% vs. 27.3 +/- 8.3%). Apart from CD19 values (21.9 +/- 10.4% vs. 12.0 +/- 3.2%) there were no significant differences between CAPD patients without infection and the control group in the laboratory parameters studied. On the other hand, CD3 (66.3 +/- 7.9% vs. 55.9 +/- 9.7%), CD4 (38.4 +/- 7.1% vs. 28.0 +/- 5.4%), and CD19 (6.3 +/- 3.3% vs. 12.0 +/- 3.2%) levels were significantly higher in CAPD patients with infection compared with the controls. CAPD patients with infection showed significantly lower NK activity (12.7 +/- 7.1% vs. 27.3 +/- 8.3%) than those in the control group. In conclusion, these results can explain the increased vulnerability to peritonitis in CAPD patients compared with healthy subjects. Additionally, immunologic status can predict the development of peritonitis in children treated with CAPD.

Adolescent↗
PubMed1998

Echocardiographic evaluation in children treated with CAPD.

The aim of this study was to evaluate systolic and diastolic cardiac functions in children treated with continuous ambulatory peritoneal dialysis (CAPD). This study included a total of 21 patients (12 boys, 9 girls), aged 23 months to 14 years (average age: 10.1 +/- 4.32 years). The mean duration on CAPD was 12.88 +/- 6.69 months (range: 2-22 months). Twenty age- and sex-matched healthy subjects served as controls. Evaluation was made at the beginning of CAPD treatment in these 21 patients. Tests were repeated in 9 of 21 patients who had completed a 1-year follow-up period. We measured systolic functions [ejection fraction (EF), and fractional shortening (FS)], and diastolic functions [early (E) and late (A) diastolic peak inflow velocities, and E/A ratio, as well as early diastolic flow deceleration velocity (EF slope) and time (dt) functions] using two-dimensional, M-mode, color Doppler echocardiography. Interventricular septum thickness was also recorded. Blood pressure (BP) levels were monitored serially in all patients. Statistical evaluation was made using Student's t-test. Compared with control subjects, systolic and diastolic parameters were significantly inversely affected in patients on CAPD (P < 0.05). The mean BP levels did not differ significantly between CAPD patients and controls. In 9 patients with a second measurement on CAPD, systolic and diastolic cardiac functions tended to have deteriorated. However, these changes were not statistically significant (P > 0.05). In conclusion, CAPD is the preferable option in children with end-stage renal disease to maintain stable cardiac functions. However, systolic and diastolic dysfunctions tend to progress in children on CAPD.

Adolescent↗
PubMed1997

Synthesis of some 2-benzoxazolinone derivatives and their analgesic properties.

In this study, the synthesis and analgesic activities of some new 6-acyl-3-(4-substituted benzoylmethyl)-2-benzoxazolinone derivatives are reported. Their structures were confirmed by microanalysis, IR, and NMR spectral analysis. The obtained compounds were screened for their analgesic activities. Analgesic activity of these compounds was investigated by modified Koster Test. The 11 compounds synthesized showed good analgesic activities.

Analgesics, Non-Narcotic↗
PubMed1992

Synthesis of 3-(2-pyridylethyl)benzoxazolinone derivatives: potent analgesic and antiinflammatory compounds inhibiting prostaglandin E2.

Fourteen new 3-[2-(2- and/or 4-pyridyl)ethyl]benzoxazolinone derivatives have been synthesized by reacting 2- and/or 4-vinylpyridine and appropriate benzoxazolinones. Their chemical structures have been proven by IR, 1H-NMR, and elemental analysis. Analgesic activities of these compounds were investigated by a "Modified Koster's Test". Except for compounds 10 and 11, all the new derivatives showed higher analgesic activities than aspirin. Therefore the compounds were screened for their antiinflammatory activities using the carrageenan hind paw edema test. The compounds (6, 7, 8, 9, 14, and 17) that showed high antiinflammatory activity were then further screened for their ability to inhibit prostaglandin E2 (PGE2) induced paw edema. Although all the benzoxazolinone derivatives synthesized in this study showed higher antiinflammatory activity compared to indomethacin, those without a substituent at the 6-position of the ring were significantly more active than the rest of the group, and their ulcerogenic activities and ED50 values indicate them as promising derivatives for further study.

Analgesia↗
PubMed1992

Studies on some 10-[2-(N,N-disubstituted thiocarbamoylthio)acetyl]phenothiazine derivatives.

Nineteen 10-[2-(N,N-disubstituted thiocarbamoylthio) acetyl]phenothiazine derivatives have been synthesized by the reaction of 10-chloroacetylphenothiazine with potassium salt of N,N-disubstituted dithiocarbamic acid derivatives. The structures of the compounds have been elucidated by UV, IR, 1H-NMR spectra and microanalysis. The anticholinergic activity of the compounds was determined by assessing the inhibition of acetylcholine using atropine sulfate as a control. Results are discussed in relation to the activity and structure of the synthesized compounds.

Acetylcholine↗
PubMed1992

Synthesis and pharmacology of some new carbamodithioic acid esters.

In this study 13 new dithiocarbamates were prepared by reacting 3-methyl-6-chloroacetyl-benzoxazolinone with potassium N,N-disubstituted dithiocarbamate derivatives. The structures of the compounds were confirmed by UV, IR, 1H-NMR, mass spectroscopic methods and elementary analysis. The anticholinergic activity was tested on rabbit ileum. With exception of one compound all derivatives exhibited a stronger antihistaminic activity as compared with their anticholinergic action.

Animals↗
PubMed1991

Synthesis of some 2-benzoxazolinone derivatives and their analgesic properties.

In this study, eight new 1-(2-benzoxazolinone-6-yl)-2-(4-arylpiperazine-1-yl)ethanol and -propanol derivatives have been prepared. Their structures have been elucidated by IR- and 1H-NMR-spectra and by elementary analysis. The analgesic activities of these compounds, using modified Koster's test have been investigated. 1-(5-Chloro-3-methyl-2-benzoxazolone-6-yl)-2-[4-(2-methoxyphenyl)p iperazine-1- yl]ethanol has been found more active than O-acetyl-salicylic acid, respectively.

1-Propanol↗
PubMed1989

Synthesis of some new Mannich bases derived from 6-acyl-3-(3,5-dimethylpiperidinomethyl)-2(3H)-benzoxazolones+ ++ and their biological activities.

A number of 6-acyl-3-(3,5-dimethylpiperidinomethyl)-2(3H)-benzoxazolones have been synthesized by Mannich reaction and their antibacterial and antifungal activities have been tested. Their chemical structures have been proved by means of their IR, NMR, mass spectroscopic data and by elementary analysis. Investigation of antimicrobial activity of compounds was done by tube dilution and paper disc techniques using bacteria (Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Staphylococcus faecalis RSKK 10541) and yeast-like fungi (Candida parapsilosis, Candida albicans, Candida pseudotropicalis, Candida stellatoidea). Among the compounds tested 6-(2-chlorobenzoyl)-3-(3,5-dimethylpiperidinomethyl)-2(3H)-benz oxazolone (Compound 2) and 6-(3-chlorobenzoyl)-3-(3,5-dimethylpiperidinomethyl)-2(3H)-benz oxazolone (Compound 3) showed the most favorable activity.

Amines↗
PubMedDate not supplied

Synthesis and biological activity of 6-acyl-3-substituted-2(3H)-benzoxazolones.

The preparation of a series of 6-acyl-3-substituted-2-(3H)-benzoxazolones is described. Their structures have been elucidated by UV, IR, NMR, MS and elementary analysis. These compounds have been tested for their antimicrobial activities against to Escherichia coli ATCC 25922, Staphylococcus aureus, ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Staphylococcus faecalis RSKK 10541, Candida parapsilosis, Candida albicans, Candida pseudotropicalis, Candida stellatoidea.

Anti-Bacterial Agents↗