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The difference sequence spaces l(infinity)(Delta), c(Delta) and c(0)(Delta) were studied by Kizmaz [Canad. Math. Bull. 24 (2) (1981) 169]. The sequence spaces a(0)(r) and a(c)(r) have been recently defined and examined by Aydin an...
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The difference sequence spaces l(infinity)(Delta), c(Delta) and c(0)(Delta) were studied by Kizmaz [Canad. Math. Bull. 24 (2) (1981) 169]. The sequence spaces a(0)(r) and a(c)(r) have been recently defined and examined by Aydin and Basar in [Hokkaido Math. J., in press]. The main purpose of the present paper is to introduce the spaces a(0)(r)(Delta) and a(c)(r)(Delta) of difference sequences. Moreover, it is proved that the spaces a(0)(r)(Delta) and a(c)(r)(Delta) are the BK-spaces including the spaces c(0) and c, and some inclusion relations have been given. It is also proved that the sequence space a(0)(r) has AD property while the space a(0)(r)(Delta) has not. Furthermore, the basis and the alpha-, beta- and gamma-duals of the spaces a(0)(r)(Delta) and a(c)(r)(Delta) have been determined. The last section of the paper has been devoted to theorems on the characterizations of the matrix classes (a(c)(r)(Delta) : l(p)) and (a(c)(r)(Delta) : c), and the characterizations of some other matrix classes have been obtained by means of a given basic lemma, where 1 less than or equal to p less than or equal to infinity. (C) 2003 Elsevier Inc. All rights reserved.
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Objective: Attention Deficit Hyperactivity Disorder (ADHD) persists through adolescence and adulthood, and 15-80% of the children diagnosed with ADHD continue to have the disorder into adulthood, depending on the diagnostic criter...
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Objective: Attention Deficit Hyperactivity Disorder (ADHD) persists through adolescence and adulthood, and 15-80% of the children diagnosed with ADHD continue to have the disorder into adulthood, depending on the diagnostic criteria used; however, these findings have mostly been derived from follow-up studies in North America. The longitudinal outcomes of ADHD children from non-Western countries, such as Turkey, and the prognostic differences between ADHD+Oppositional Defiant Disorder (ODD) and ADHD+Conduct Disorder (CD) cases require further exploration. Six years after an initial study of 18 months conducted between 2000 and 2002, we sought to evaluate 120 cases of ADHD with comorbid ODD or CD. Methods: The original sample included 120 ADHD + ODD/CD children, followed for 18 months during 2000-2002. We evaluated the last-known psychiatric status, academic achievement, substance use, and social functionality of 60 children who were interviewed six years earlier. The treatment duration was divided into three groups: less than 15 months, 15-45 months, and greater than 45 months. Results: In the initial study, we found that both combined treatment (parent training and stimulant treatment) and only stimulant treatment were effective in reducing ADHD, ODD, and CD symptoms. Six years after the initial study, the ADHD treatment was found to be effective in many areas, including academic success (p<0.001), grade retention (p=0.026), expulsion or suspension from school (p=0.009), rate of accidents and broken bones requiring reduction (p=0.001), and cigarette smoking (p=0.018). Conclusions: ADHD symptoms are associated with impairments in multiple functional domains, and ADHD treatment is effective for Turkish children in many of these domains. There is a statistically significant difference in treatment success between groups created according to the treatment duration.
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Apoptosis, known as programmed cell death, is defined as a cell's preferred form of death under hectic conditions through genetically conserved and complex pathways. There is a decisive balance between stimulatory and inhibitory s...
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Apoptosis, known as programmed cell death, is defined as a cell's preferred form of death under hectic conditions through genetically conserved and complex pathways. There is a decisive balance between stimulatory and inhibitory signaling pathways to maintain homeostasis in cells. In order to shift the balance towards apoptosis, the modulation of both apoptotic and anti-apoptotic pathways represents an attractive target for cancer therapeutics. Currently, chemotherapy and radiotherapy are among the most commonly used treatment modalities against lung cancer. Tumor suppressor gene, p53, is required in order for both of these treatment methods to work as anti-tumor agents. As a result, tumors lacking p53 display resistance to both chemotherapy and radiotherapy. However, death ligands induce apoptosis regardless of p53 status of cells. Thus, these methods constitute a complementary therapeutic approach to currently employed conventional treatment modalities. At present, death ligands are being evaluated as potential cancer therapeutic agents. Since resistance to tumor necrosis factor (TNF)-alpha-mediated apoptosis represented an obstacle for the treatment of patients with lung carcinoma in the earlier attempts, an extensive research was recently initiated to understand molecular mechanism of TNF-alpha signaling. NF-kappaB transcription factors have been demonstrated to modulate the apoptotic program, mostly as blockers of apoptosis in different cell types. In this review, we concentrate on the current progress in the understanding of TNF-alpha-mediated apoptosis for lung carcinoma. Representative models of NF-kappaB-inhibiting gene therapy strategies from various labs including ours are also provided as examples of up-to-date approaches to defeat TNF resistance. In order to give the reader better understanding and appreciation of such approaches, previously unpublished in vivo assays are also incorporated into this review. Current progress in clinical trials using adenovirus-mediated delivery of TNF-alpha isalso discussed.
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XLalphas, a variant of the stimulatory G protein alpha-subunit (Gsalpha), can mediate receptor-activated cAMP generation and, thus, mimic the actions of Gsalpha in transfected cells. However, it remains unknown whether XLalphas ca...
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XLalphas, a variant of the stimulatory G protein alpha-subunit (Gsalpha), can mediate receptor-activated cAMP generation and, thus, mimic the actions of Gsalpha in transfected cells. However, it remains unknown whether XLalphas can act in a similar manner in vivo. We have now generated mice with ectopic transgenic expression of rat XLalphas in the renal proximal tubule (rptXLalphas mice), where Gsalpha mediates most actions of PTH. Western blots and quantitative RT-PCR showed that, while Gsalpha and type-1 PTH receptor levels were unaltered, protein kinase A activity and 25-hydroxyvitamin D 1-alpha-hydroxylase (Cyp27b1) mRNA levels were significantly higher in renal proximal tubules of rptXLalphas mice than wild-type littermates. Immunohistochemical analysis of kidney sections showed that the sodium-phosphate cotransporter type 2a was modestly reduced in brush border membranes of male rptXLalphas mice compared to gender-matched controls. Serum calcium, phosphorus, and 1,25 dihydroxyvitamin D were within the normal range, but serum PTH was approximately 30% lower in rptXLalphas mice than in controls (152 +/- 16 vs. 222 +/- 41 pg/ml; P < 0.05). After crossing the rptXLalphas mice to mice with ablation of maternal Gnas exon 1 (E1(m-/+)), male offspring carrying both the XLalphas transgene and maternal Gnas exon 1 ablation (rptXLalphas/E1(m-/+)) were significantly less hypocalcemic than gender-matched E1(m-/+) littermates. Both E1(m-/+) and rptXLalphas/E1(m-/+) offspring had higher serum PTH than wild-type littermates, but the degree of secondary hyperparathyroidism tended to be lower in rptXLalphas/E1(m-/+) mice. Hence, transgenic XLalphas expression in the proximal tubule enhanced Gsalpha-mediated responses, indicating that XLalphas can mimic Gsalpha in vivo.
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In addition to tumor size, it has been suggested that P-glycoprotein (P-gp) expression and/or oxyphilic cell content in parathyroid adenomas has an important influence on the results of technetium 99m methoxyisobutylisonitrile (Tc...
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In addition to tumor size, it has been suggested that P-glycoprotein (P-gp) expression and/or oxyphilic cell content in parathyroid adenomas has an important influence on the results of technetium 99m methoxyisobutylisonitrile (Tc-99m MIBI) parathyroid imaging. AIM: In this study, we compared the results of MIBI parathyroid imaging and immunohistochemical analysis (IHA) of P-gp expression, oxyphilic cell content, and tumoral tissue volume in parathyroid adenomas. We also evaluated the relationship between MIBI and ultrasound (US) results, operation findings, serum biochemical values. MATERIALS AND METHODS: Forty (40) patients (36 female and 4 male; mean age, 53.2 +/- 8.16 years) with hyperparathyroidism who had undergone surgery were included in this study. Preoperatively, "double phase" parathyroid scintigraphy with Tc-99m MIBI (including imaging of the neck and mediastinum) was performed in all patients. Thirty-two (32) of the patients had also neck US. Serum parathormon (PTH), calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) levels were measured preoperatively. In resected parathyroid tissues, P-gp expression and percentage of oxyphilic cell content were analyzed with IHA in 34 patients. RESULTS: Three (3) of the resected parathyroid tissues were hyperplastic parathyroid tissue, whereas 31 of the tissues were parathyroid adenoma (mean volume, 1.99 +/- 1.93 mL). In Tc-99m MIBI parathyroid scintigraphy, 70% of the parathyroid adenoma/hyperplastic parathyroid tissue was detected in correct localization; at US, this rate was 46.8%. According to the resected parathyroid tissue localization at surgery, sensitivity, accuracy, positive predictive value, and prevalence in scintigraphy were 82.3%, 70%, 82.3%, and 85%, respectively. Those were 60%, 46.8%, 68.2%, and 78.1% for US, respectively. No significant correlation and no concordance was found between MIBI and US results (kappa, -0.103, r = -0.11; p: 0.53). Interestingly, significant correlation was found between tumoral volume and ALP level (r = 0.42; p = 0.010) and between PTH and ALP levels (r = 0.72; p < 0.001). Significant correlation was also found between patient age and tumoral volume (r =-0.37; p = 0.02) and between PTH and serum Ca levels (r = 0.32; p = 0.04). In 23 of 34 patients in whom histopathological examination was done MIBI was positive and in 13 of these patients (56.5%), P-gp expression was positive. When the histopathological results and MIBI results were compared, there was no significant correlation and concordance between P-gp expression (kappa = 0.09, r = 0.10; p = 0.54), oxyphilic cell content (r = -0.17; p = 0.33), and tumoral tissue volume (r = -0.14; p = 0.38). In 12 of 19 patients (63%) who had parathyroid tissue < 1 mL and in 15 of 24 patients (62.5%) who had oxyphilic cell content < 10%, lesions were also detected correctly with MIBI scintigraphy. CONCLUSIONS: Present study results suggest that MIBI scintigraphy was clearly superior to US as a diagnostic tool. However, P-gp expression, oxyphilic cell content,and tumoral volume may have not a main effect on MIBI parathyroid scintigraphy results in parathyroid adenoma.
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This study investigated the strength characteristics of various composites (Tetric Ceram, Tetric Flow, Prisma AP.H, Synergy Duo Shade, Synergy Compact, and Z 100) and compomers (Compoglass, Compoglass F, Dyract AP, F 2000) that we...
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This study investigated the strength characteristics of various composites (Tetric Ceram, Tetric Flow, Prisma AP.H, Synergy Duo Shade, Synergy Compact, and Z 100) and compomers (Compoglass, Compoglass F, Dyract AP, F 2000) that were applied in a Class V cavity of a maxillary central incisor. The study was conducted by using a 3-dimensional finite element approach and in the study ansys package program was used. The tooth model had 294 elements and 420 nodes. The teeth considered were assumed to be subjected to an incisal load of 200 N acting at an angle of 26 degrees with the longitudinal axis of the tooth but the effects of different loading angles and different loads were also analysed. Hence, the loads of 100 and 400 N and the loading angles of 0 degrees representing bruxism and 90 degrees representing a traumatic load were also taken into consideration. The effects of the cavity preparation size were also studied. It was determined that any increase in the loading angle and/or the amount of the load resulted in a proportional increase in the stresses developed in the tooth. Furthermore it was also verified that, as a cavity weakens the tooth structure by creating a discontinuity in an intact tooth, the larger sized cavity preparations inevitably cause larger stresses to be developed in the tooth. Strictly from the mechanical point of view, the stresses developed in the restored teeth were determined to be inversely proportional with the modulus of elasticity of the restorative materials. Therefore within the scope of the study Z 100 was found to be superior to the other materials concerned.
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Elastosonography (ES) is a newly developed method that is used for the differential diagnosis of benign and malignant thyroid nodules. In different studies, ES scoring has been compared with histopathological findings, and sensiti...
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Elastosonography (ES) is a newly developed method that is used for the differential diagnosis of benign and malignant thyroid nodules. In different studies, ES scoring has been compared with histopathological findings, and sensitivity and specificity of the scoring were calculated. In this study, it determines the strain index (SI) as well as the ES to score thyroid nodules, and establishes the role for these parameters in the differential diagnosis of thyroid nodules using histopathological analysis as a reference standard. Real-time ES in transverse axis (TA) and longitudinal axis (LA) was performed in 391 nodules of 292 patients. ES scoring was made for all the nodules. SI in TA and LA was calculated for four times in each nodule and mean values were determined. The results were compared with final histopathological diagnoses. In histopathological examinations, 125 (31.97%) of 391 nodules were malignant and 266 (68.03%) were benign. Of these histopathologically benign nodules, 189 (%71.05) were also probably benign according to elastosonographic scoring (scores of 1, 2, or 3), while 77 (28.95%) were probably malignant (scores of 4 or 5). Among 125 histopathologically malignant nodules, 52 (41.60%) were probably benign and 73 (58.40%) were probably malignant according to elastosonographic scoring. There was a significant relation between scoring and histopathological findings (chi(2) = 36.513; P < 0.001). Accordingly, sensitivity and specificity of ES scoring were 58.4 and 71.0%, respectively. ROC analysis value obtained for strain ratios in LA (AUC: 75.5%; P < 0.001) had a higher significance compared to ROC analysis value obtained for strain ratios in TA (AUC: 66.0%). Thus, ROC analysis evaluation was applied only for SI in LA. The optimal SI cut-off value in LA for all the nodules was found to be 16.709 (sensitivity: 73.4%, specificity: 70.0%) (AUC: 75.4 +/- 0.03%; 70.2-80.5%). SI cut-off value corresponding to 90% sensitivity in this axis was 4.516 (specificity: 35.7%). Sensitivity and specificity of SI values that were determined according to morphological features of nodules in gray-scale ultrasonography were higher. For hypoechoic nodules with microcalcifications and without a halo, SI cut-off value, sensitivity, and specificity were 17.020, 84.3, and 81.1%, respectively. Our study is the first clinical-wide series study that measured, used, and compared the ES scoring and SI cut-off values for the differential diagnosis of benign and malignant thyroid nodules. This study indicates that measurement of SI with ES as a noninvasive procedure may be used as an adjunctive method to the conventional methods for the differential diagnosis of thyroid nodules.
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An outbred rat model of novelty-seeking phenotype has predictive value for the expression of locomotor sensitization to nicotine. When experimentally naive rats are exposed to a novel environment, some display high rates of locomo...
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An outbred rat model of novelty-seeking phenotype has predictive value for the expression of locomotor sensitization to nicotine. When experimentally naive rats are exposed to a novel environment, some display high rates of locomotor reactivity (HRs, scores ranking at top 1/3rd of the population), whereas some display low rates (LRs, scores ranking at bottom 1/3rd of the population). Basally, HRs display lower anxiety-like behavior compared to LRs along with higher neuropeptide Y (NPY) mRNA in the amygdala and the hippocampus. Following an intermittent behavioral sensitization to nicotine regimen and 1 wk of abstinence, HRs show increased social anxiety-like behavior in the social interaction test and robust expression of locomotor sensitization to a low dose nicotine challenge. These effects are accompanied by a deficit in NPY mRNA levels in the medial nucleus of the amygdala and the CA3 field of the hippocampus, and increases in Y2R mRNA levels in the CA3 field and corticotropin releasing factor (CRF) mRNA levels in the central nucleus of the amygdala. Systemic and daily injections of a Y2R antagonist, JNJ-31020028, during abstinence fully reverse nicotine-induced social anxiety-like behavior, the expression of locomotor sensitization to nicotine challenge, the deficit in the NPY mRNA levels in the amygdala and the hippocampus, as well as result an increase in Y2R mRNA levels in the hippocampus and the CRF mRNA levels in the amygdala in HRs. These findings implicate central Y2R in neuropeptidergic regulation of social anxiety in a behavioral sensitization to nicotine regimen in the LRHR rats.
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Physical restraint of rodents is needed for nose-only exposure to airborne toxicants and is also used as a means of psychological stress. Hyperthermia is often observed in restrained rats, presumably as a result of impairments in ...
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Physical restraint of rodents is needed for nose-only exposure to airborne toxicants and is also used as a means of psychological stress. Hyperthermia is often observed in restrained rats, presumably as a result of impairments in heat dissipation. However, such a hyperthermic response should be dependent on the prevailing ambient conditions. To understand how ambient temperature (T(a)) affects the thermoregulatory response to restraint, core temperature (T(c)) and heart rate (HR) were monitored by telemetry in rats subjected to 1 h of physical restraint while T(a) was maintained at 14-30 degrees C in 2 degrees C increments. The T(c) of unrestrained rats was unaffected by T(a). During restraint, T(c) was elevated at ambient temperatures with the exception of 14 degrees C, at which the rats became mildly hypothermic. There was an inverse relationship between T(a) and HR in both unrestrained and restrained rats; however, HR was significantly elevated in restrained rats at all ambient temperatures except 22 and 24 degrees C. Heat loss from the tail, estimated from T(c) and tail skin temperature, was markedly reduced at all but the highest ambient temperatures in restrained rats. The data suggest that the T(a) limits of normothermia are narrowed in the restrained rat. That is, between 16 and 20 degrees C, the rat maintains a relatively stable T(c) that is slightly elevated above that of the unrestrained rat. At ambient temperatures above or below this range, the rat shows signs of hyperthermia and hypothermia, respectively. In contrast, the limits of normothermia for unrestrained rats range from 14 (or lower) to 30 degrees C. Overall, the ideal T(a) for restrained rats appears to be 20 degrees C and no higher than 22 degrees C for the thermoregulatory system to maintain a regulated T(c) in rats well adapted to physical restraint.
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AIM: To test the hypothesis that, Epiphany, either in its mixed form or as separate components, can alter the vascular reactivity of isolated rat thoracic aorta. The possible mechanism of its vascular action was also investigated....
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AIM: To test the hypothesis that, Epiphany, either in its mixed form or as separate components, can alter the vascular reactivity of isolated rat thoracic aorta. The possible mechanism of its vascular action was also investigated. METHODOLOGY: The relaxant effect of the base, the catalyst and mixed Epiphany on isolated rat aortic rings pre-contracted with phenylephrine (PE) was tested. The aortic rings were then incubated with either nitric oxide synthase (NOS) inhibitor, cyclooxygenase (COX) inhibitor or K(+) channel inhibitors; after pre-contraction with PE, relaxations to the various compounds of Epiphany were examined. In another set of experiments, to investigate the Ca(2+)channel antagonistic effect of the Epiphany, the effect of these compounds in Ca(2+)-free solution on extracellular Ca(2+)(CaCl(2))-induced contraction in high-K(+) pre-challenged rings (in K(+)-depolarized rings) was examined to determine whether the direct inhibition of [Ca(2+)] influx increase accounted for the vasodilatory effects of these compounds. For comparison, L-type Ca(2+)channel blocker nifedipine (1 micromol L(-1)), instead of Epiphany compounds, was assayed in adjacent rat aortic rings in parallel. RESULTS: The catalyst and the mixture of Epiphany induced concentration-dependent relaxations. However, the base of Epiphany did not cause relaxation in rat aorta. The relaxation responses were not significantly altered by incubation of aorta with NOS, COX and potassium channel inhibitors. Whilst nifedipine, the catalyst and the mixture of Epiphany inhibited CaCl(2)-induced contractions (P < 0.05), the base of Epiphany did not inhibit CaCl(2)-induced contractions significantly (P > 0.05). CONCLUSION: Epiphany induced relaxation of rat aorta via a calcium antagonistic effect. Provided that the vasodilatory effect elicited by Epiphany can be reversed by the circulation, its haemorrhagic potential by virtue of permanent vascular dilatation can be ignored.
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