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The effect of platelet-rich fibrin on autologous osteochondral transplantation: An in vivo porcine model. Knee 2017; 24:1392-1401. [PMID: 29037743 DOI: 10.1016/j.knee.2017.08.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 08/02/2017] [Accepted: 08/10/2017] [Indexed: 02/02/2023]
Abstract
BACKGROUND This work aimed to evaluate the efficacy of cartilage transplantation to the medial femoral condyle±platelet-rich fibrin (PRF) augmentation in a porcine model. The hypothesis of the study was that PRF may act as a bioactive cell scaffold to fill defects and enhance cartilage regeneration. METHODS Thirty-two knees of 16 miniature pigs were randomly assigned to four groups. The critical-size osteochondral defects (8x5mm) in femoral condyle of both knees were treated with one of the following: group 1-untreated controls; group 2-cartilage fragments alone; group 3-PRF alone; group 4-PRFT+cartilage fragments. After completion of the surgical implantation, the periosteal patch harvested from the proximal tibia was sutured onto the cartilage of the medial condyle to cover the implanted defects. Animals were sacrificed at six months after treatment. The regenerated cartilages were assessed by gross inspection and histological examination. RESULTS The best results were obtained with the repair tissue being hyaline-like cartilage (group 4). The grading score of histological evaluation demonstrated that group 4 had better matrix, cell distribution and cartilage mineralization than group 2 and group 3. PRF showed a positive effect on the cartilage repair; the procedure was more effective when PRF was combined with autologous chondrocytes. CONCLUSIONS This approach may provide a successfully employed technique to target cartilage defects in vivo. Larger groups and longer periods of study may provide more definitive and meaningful support for using this therapeutic approach as a new way of cartilage regeneration.
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Abstract
Inflammation of the parathyroid glands is rare when compared to other endocrine organs. This leads to the use of descriptive terms as well as the lack of a generally accepted classification for inflammatory disorders of the parathyroid glands. This review article proposes that parathyroid inflammation be subdivided morphologically into (a) non-specific lymphocytic infiltration, which is more an expression of damage to small vessels, due to e. g. severe systemic inflammation or myocardial infarction, (b) autoimmunogenic lymphocytic parathyroiditis, (c) nonimmunogenic inflammation caused by granulomatous diseases or infections and (d) invasive sclerosing (peri) parathyroiditis. As only parathyroid glands removed due to hyperparathyroidism and normal parathyroid glands incidentally removed during thyroid surgery are seen almost exclusively in routine histopathology, virtually no information about the morphological correlate of hypoparathyroidism is available.
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Increased risk of a herpes zoster attack in patients receiving androgen deprivation therapy for prostate cancer. Andrologia 2017; 50. [PMID: 28786220 DOI: 10.1111/and.12863] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2017] [Indexed: 01/04/2023] Open
Abstract
This study aimed to examine the association of herpes zoster (HZ) with androgen deprivation therapy (ADT) use among patients with prostate cancer (PC), using a population-based data set. The study sample for this study was retrieved from the Taiwan Longitudinal Health Insurance Database 2005. We selected 877 patients with PC who had received ADT as the study group, while 849 patients with PC who had not received ADT served as the comparison group. Each study patient was individually tracked for a 3-year period to discriminate those who subsequently received a diagnosis of HZ. Of the total 1,726 sampled patients, the incidence rate of HZ per 100 person-years was 1.80 (95% CI: 1.41-2.25) during the 3-year follow-up period. In particular, incidence rates of HZ per 100 person-years were 2.36 (95% CI: 1.75-3.13) and 1.24 (95% CI: 0.81-1.81), respectively, for patients with PC who had and those who had not received ADT. Furthermore, Cox proportional hazard regressions showed that the adjusted hazard ratio for an HZ attack during the 3-year follow-up period for patients with PC who had received ADT was 1.88 (95% CI: 1.13-3.11) than those who had not received ADT. We concluded that patients with PC who had received ADT had an increased risk of HZ.
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Neoadjuvant treatment improves capsular integrity and the width of the fibrous capsule of high-grade soft-tissue sarcomas. EUROPEAN JOURNAL OF SURGICAL ONCOLOGY 2012; 39:61-7. [PMID: 23103117 DOI: 10.1016/j.ejso.2012.10.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 10/03/2012] [Accepted: 10/05/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Neoadjuvant treatment is thought to improve resection with margin-negative surgery in locally advanced soft-tissue sarcomas (STS). Treatment-induced alterations of the tumor peripheryhave not yet been microscopically evaluated. OBJECTIVE This histopathological study compared limb STS with primary resection and those that had undergone neoadjuvant treatment, emphasizing microscopic changes of the fibrous capsule (FC) and reactive zone (RZ) after neoadjuvant treatment. PATIENTS AND METHODS Patients with primary high-grade limb sarcomas (N = 76) which have not previously been treated were included. Of those, 37 were primarily resected and 39 were treated with one of the following neoadjuvant treatment modalities: 7x chemotherapy (CTX), 3x radiotherapy (RT), 15x isolated limb perfusion (ILP), 8x CTX + RT, and 6x CTX + ILP. Sizes of the FC and RZ were microscopically measured, and FC-integrity was documented. Histopathologic regression was expressed as a percent. RESULTS Only 35.1% of untreated sarcomas showed an intact FC. We observed significantly higher capsular integrity after treatment (76.9%). Additionally, the average width of the FC (0.21 mm vs. 0.61 mm) and RZ (0.67 mm vs. 1.48 mm) increased significantly. The extent of histopathologic regression showed a correlation with capsular integrity and width. The combination of two treatment modalities (CTX + RT or ILP) showed strongest effects at the tumor periphery. CONCLUSIONS Neoadjuvant treatment stabilizes the tumor periphery in STS (e.g., the capsule). Concerning local treatment strategies, these novel histopathologic insights might significantly influence the decision as to whether primary resection is advisable in advanced local soft-tissue sarcoma.
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Adiabatically slow and adiabatically fast driven ratchets. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:041116. [PMID: 22680428 DOI: 10.1103/physreve.85.041116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2012] [Indexed: 06/01/2023]
Abstract
We revisit two known models of deterministically driven ratchets, which exhibit high energetic efficiency, with the goal to uncover similarities and differences in the principles of their operation. Both the models rely on adiabaticity of the potential change process, however, the adiabaticity that we deal with in the two cases is of different types, slow and fast. It is shown that in the former (latter) case the drift velocity is an even (odd) functional of the potential, with the notable consequence that for the adiabatically slow driven ratchet the necessary symmetry breaking occurs only due to time-dependent parametric perturbations, while the spatial asymmetry of the potential is a mandatory condition for the adiabatically fast driven ratchet to operate. To treat energetic characteristics, the models are restated in terms of traveling potential ratchets. With such an approach, we find that in these cases (i) the conditions of high energetic efficiency to be reached are similar, and (ii) the symmetry properties of the kinetic coefficients are different. Based on our results, a strategy for designing efficient Brownian motors is suggested.
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Two-state Brownian motor driven by synchronously fluctuating unbiased forces. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:021104. [PMID: 21928946 DOI: 10.1103/physreve.84.021104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2011] [Indexed: 05/31/2023]
Abstract
As a model of the Brownian motor, we consider a particle moving unidirectionally under the action of two synchronously fluctuating unbiased forces, transverse and longitudinal with respect to the particle track. The former force induces track-normal transitions of the particle between the attached and detached states (with and without a periodic potential, respectively), whereas the latter drives track-parallel motion in either state. Analytical expressions of the current and efficiency are derived for different regimes, with due account of the delayed response of the system to force fluctuations. For a sawtooth potential in the attached state, we reveal several motion regimes affording the maximum current or the maximum efficiency. A special emphasis is placed on the possibility of current reversal. As shown, the interplay between two phase-shifted harmonically varied forces as well as inherent and externally induced asymmetry can lead to the emergence of multiple current reversals, thus enabling the flexible controllability of the motion direction.
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Differential expression of microRNA-675, microRNA-139-3p and microRNA-335 in benign and malignant adrenocortical tumours. J Clin Pathol 2011; 64:529-35. [PMID: 21471143 PMCID: PMC3099361 DOI: 10.1136/jcp.2010.085621] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND For the clinical management of adrenocortical neoplasms it is crucial to correctly distinguish between benign and malignant tumours. Even histomorphologically based scoring systems do not allow precise separation in single lesions, thus novel parameters are desired which offer a more accurate differentiation. The tremendous potential of microRNAs (miRNAs) as diagnostic biomarkers in surgical pathology has recently been shown in a broad variety of tumours. METHODS In order to elucidate the diagnostic impact of miRNA expression in adrenocortical neoplasms, a cohort of 20 adrenocortical specimens including normal adrenal tissue (n=4), adrenocortical adenomas (ACAs) (n=9), adrenocortical carcinomas (ACCs) (n=4) and metastases (n=3) was analysed using TaqMan low density arrays to identify specific miRNA profiles in order to distinguish between benign and malignant adrenocortical lesions. Results were validated in a validation cohort (n=16). RESULTS Concerning the differential diagnosis of ACAs and ACCs, 159 out of 667 miRNAs were up- and 89 were down-regulated in ACAs. Using real-time PCR analysis of three of the most significantly expressed single key miRNAs allowed separation of ACAs from ACCs. ACCs exhibited significantly lower levels of miR-139-3p (up to 8.49-fold, p<0.001), miR-675 (up to 23.25-fold, p<0.001) and miR-335 (up to 5.25-fold, p<0.001). A validation cohort of 16 specimen with known Weiss score showed up-regulation of miR-335 and miR-675 in the majority of cases with probable malignant course, although overlapping values exist. CONCLUSION miRNA profiling of miR-675 and miR-335 helps in discriminating ACCs from ACAs. miRNA analysis may indicate malignant behaviour in cases with indeterminate malignant potential.
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Abstract
Multiple endocrine neoplasia type 2 (MEN 2) is an autosomal dominant inherited cancer syndrome with the major components medullary thyroid carcinoma, pheochromocytoma and hyperparathyroidism. Due to the clinical course three distinct subtypes are distinguished, MEN 2A, MEN 2B and familial medullary thyroid carcinoma. The disease is caused by germ-line mutations of the RET proto-oncogene and the localization of these mutations correlates with the onset of the development of medullary thyroid carcinoma, which is crucial for the clinical course and outcome of the disease. It therefore has a substantial influence on the clinical management of the affected patients and their relatives. This review summarizes the morphology and clinic of MEN 2-associated tumors and their respective precursor lesions.
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Abstract
Approximately 5% of differentiated thyroid carcinomas with follicular cell differentiation, papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) and 25-30% of medullary thyroid carcinoma (MTC) are hereditary. They occur either as part of a defined syndrome or are confined to the thyroid gland. Compared to their sporadic non-hereditary counterparts hereditary thyroid carcinomas generally develop earlier and regularly show multifocal tumour growth. With the exception of familial MTC, which is preceded by neoplastic C cell hyperplasia, no precursor lesions of hereditary thyroid carcinoma are known. In strong correlation with the localisation of the germline mutation of the RET protooncogene, familial MTC shows a distinct clinical course which allows precise clinical decision-making for prophylactic thyroidectomy to prevent invasive MTC. According to current knowledge prophylactic thyroidectomy of all other types of hereditary thyroid carcinoma is not justified.
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Neurological picture. Tongue pseudohypertrophy in idiopathic hypoglossal nerve palsy. J Neurol Neurosurg Psychiatry 2009; 80:1393. [PMID: 19917820 DOI: 10.1136/jnnp.2008.169938] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Analysis of deregulated miRNAs is helpful to distinguish poorly differentiated thyroid carcinoma from papillary thyroid carcinoma. Horm Metab Res 2009; 41:475-81. [PMID: 19370508 DOI: 10.1055/s-0029-1215593] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Poorly differentiated thyroid carcinoma (PDTC) is defined as a malignant follicular cell derived neoplasm, both morphologically and biologically intermediate between well differentiated and anaplastic thyroid carcinoma (ATC). In the present study we investigated the expression levels of two distinct sets of miRNAs ('set 1': miRNA-146b, -181b, -21, -221, -222, all shown to be significantly upregulated in papillary thyroid carcinoma [PTC]; 'set 2': miRNA-30d, -125b, -26a, -30a-5p, and let7c, all downregulated in ATC) in a series of 15 PDTC (including 3 mixed PDTC/PTC), 9 'pure' PTC, and 9 ATC. Compared to normal thyroid tissue all 'set 1' miRNAs were significantly upregulated in PTC (p<0.001); in ATC 4/5 miRNAs were upregulated (p<0.001) whereas in PDTC the expression levels of all 5 miRNAs did not differ significantly from normal thyroid. All miRNAs of 'set 2' were significantly upregulated in PTC (p<0.004) and downregulated in ATC (p<0.03); in PDTC only 3/5 were downregulated (p<0.011). All 10 miRNAs investigated differed significantly (p<0.003) between PTC and PDTC. In the histologically differentiated PTC compound of mixed PDTC/PTC cases, however, miRNA expression levels of all 10 miRNAs investigated lacked significant difference from those found in the PDTC compound, whereas 6/10 miRNAs differed significantly from 'pure' PTC. Our results indicate that analysis of distinct sets of miRNAs represent useful tools to distinguish PDTC from 'pure' PTC. Additionally our findings suggest that lack of deregulation of some miRNAs may select a subset of PTC prone to progression to PDTC.
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Lack of correlation between BRAF V600E mutational status and the expression profile of a distinct set of miRNAs in papillary thyroid carcinoma. Horm Metab Res 2009; 41:482-7. [PMID: 19370505 DOI: 10.1055/s-0029-1215558] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Recent studies demonstrated a significant upregulation of distinct microRNAs (miRNAs), small endogenous RNAs that regulate gene expression, in papillary thyroid carcinoma (PTC). In the pathogenesis of PTC the T1799A (V600E) BRAF mutation is the most common genetic alteration leading to a constitutive activation of the MAPK pathway. The aim of the present study was to elucidate a possible correlation between BRAF mutational status and a distinct miRNA expression profile. In a series of 221 PTC we determined the BRAF V600E mutational status using DNA-sequencing and correlated the occurrence of the mutation with a variety of clinicopathologcial data. The miRNA expression profile of five selected subtypes (miRNA-146b, -181b, -21, -221, -222) in two matched cohorts of BRAF positive (n=28) and wildtype cases (n=26) was examined by RT-PCR TaqMan miRNA assay. The BRAF V600E mutation was significantly found in PTCs with extrathyroidal extension (p <0.001). Among them, V600E was even significantly associated with smaller tumour size of 1 cm or less (microcarcinomas; p<0.003) and the follicular (p=0.017) and tall cell variant (p=0.015). By calculating relative changes in miRNA gene expression no differences in fold changes could be detected between BRAF positive and wildtype PTC suggesting that BRAF has no regulatory influence on the expression of the five examined miRNAs. However, our study confirmed the diagnostic utility of this distinct set of miRNAs to detect PTC by significant fold changes in at least 3 miRNAs (miRNA-146b, -221, -222) irrespective of its histological variant.
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Abstract
Both anaplastic thyroid carcinoma (ATC) and angiosarcoma of the thyroid (AST) are highly aggressive malignancies with very limited therapeutic options. Since selective inhibition of COX-2, for example, by celecoxib has been shown to suppress both tumour formation and progression, we investigated COX-2 protein expression in a series of ATC and AST (26 cases each) using immunohistochemistry. COX-2 expression was demonstrated in 13 ATC (50%) and 11 AST (42%); a strong COX-2 expression in more than 50% of vital tumour cells was found in 5 ATC and 5 AST, respectively. Although a recently performed phase II trial applying celecoxib failed overall to halt tumour progression in differentiated thyroid carcinoma, the two cases with partial or complete remission noted in this study were related to tumours with immunohistochemically proven strong COX-2 expression. The strong COX-2 expression observed in approximately 20% of our ATC and AST samples may thus indicate selective patients with a possible therapeutic option for an otherwise fatal disease.
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Expression and mutation analysis of the tyrosine kinase c-kit in poorly differentiated and anaplastic thyroid carcinoma. Horm Metab Res 2008; 40:685-91. [PMID: 18622894 DOI: 10.1055/s-2008-1080895] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Poorly differentiated and anaplastic thyroid carcinoma are aggressive tumors failing to res-pond to conventional therapy. Imatinib mesylate offers an effective therapeutic option in patients with various types of malignancies by inhibiting tyrosine kinases such as c-kit. In this study we investigated c-kit expression in anaplastic and poorly differentiated thyroid carcinoma compared to differentiated carcinoma and adenoma and the presence of c-kit mutations. In total, 224 thyroid tissues were analyzed by immunohistochemistry. Mutation analysis of exon 9, 11, 13, and 17 of the c-kit gene was performed in anaplastic and poorly differentiated carcinoma. c-Kit expression was negative in all anaplastic thyroid carcinoma, while c-kit expression of poorly differentiated carcinoma showed a high variability with a more intense staining in tumors showing obvious differentiated malignant follicular tumor areas. Differentiated carcinoma showed a slight, but not significantly stronger c-kit expression than poorly differentiated carcinoma. All tumors revealed wild type sequences of c-kit gene in exons 9, 11, 13, and 17. The low or lacking c-kit expression in undifferentiated thyroid carcinoma together with the lack of mutations argue against a crucial role of c-kit in thyroid carcinoma cell proliferation. Further molecular targets of imatinib mesylate have to be analyzed to estimate a potential benefit of this drug for patients with dedifferentiated thyroid carcinoma.
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Differential expression of ghrelin and its receptor (GHS-R1a) in various adrenal tumors and normal adrenal gland. Horm Metab Res 2008; 40:181-8. [PMID: 18246525 DOI: 10.1055/s-2007-1004574] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Ghrelin is a newly characterized, widely distributed peptide thought to be involved in the regulation of appetite. Significant effects on the release of growth hormone (GH) and ACTH have been demonstrated. This study compares the expression of ghrelin and its receptor (GHS-R) in various adrenal tumors and normal adrenal gland. Normal adrenal tissue was obtained after autopsy. Tissue was obtained from 13 pheochromocytomas (PHEOs), 15 cortisol-secreting adenomas (CPAs), 12 aldosterone-secreting adenomas (APAs), and 16 nonfunctional adenomas (NFAs) following laparoscopic surgery. Expression of ghrelin and GHS-R1a was investigated on RNA levels by using real-time reverse transcription polymerase chain reaction (RT-PCR) and on protein levels by using immunohistochemistry. In the seven normal adrenal glands analyzed, ghrelin mRNA levels were 12-fold lower than in stomach. Ghrelin protein expression was confirmed by immunohistochemistry. In all adrenal tumors, relevant levels of ghrelin mRNA were observed, with significantly lower expression in PHEOs and APAs than in normal adrenal gland. Ghrelin protein was detected in 0% of PHEOs, 55% of APAs, 87% of CPAs, and 54% of NFAs. GHS-R1a mRNA expression was detectable in normal adrenal gland, but the receptor protein was absent. In adrenal tumors, detectable levels of receptor mRNA were found in 38% of PHEOs, 13% of CPAs, and 25% of NFAs. GHS-R1a protein was absent in the majority of adrenal tumors. Expression of ghrelin in normal adrenal gland and adrenal tumors may indicate some unknown physiological function. The pathophysiological relevance of ghrelin expression in adrenal tumors remains to be investigated.
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Abstract
Twenty-two patients (mean age 61) with metastasizing, progressive, nonradioiodine-accumulating thyroid carcinoma of the follicular epithelium were treated with doxorubicin between 2000 and 2005. Tumors were histologically classified as follicular in 15 patients (68%) and papillary in 7 patients (32%). In addition, nine patients (mean age 51 years) with medullary thyroid carcinoma were treated with doxorubicin between 1997 and 2005. Treatment consisted of doxorubicin: either 8 cycles of 15 mg/m2 weekly or 3 cycles of 60 mg/m2 every 3 weeks, repeated once, depending on response and side effects. The effect of therapy was evaluated by radiographic imaging, [18F] FDG-PET, and bone scans. In patients with papillary or follicular thyroid carcinoma, 5% had a partial regression over 6 months, 42% had stable disease for a median of 7 months (range: 1-22), and 53% had continuous progression established over 5 months (range: 1-11). Three patients died before completing chemotherapy. In patients with medullary thyroid carcinoma, 11% had a partial regression over 6 months followed by stable disease for 3 months, 11% had stable disease over 7 months, and 79% demonstrated progressive disease established over 5 months (range: 2-12). Doxorubicin can be a valid chemotherapy option, especially for advanced or metastatic thyroid carcinoma of the follicular epithelium.
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Tri-iodothyronine as a stimulator of liver regeneration after partial and subtotal hepatectomy. Eur Surg Res 2007; 39:58-63. [PMID: 17213727 DOI: 10.1159/000098443] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2006] [Accepted: 11/14/2006] [Indexed: 01/07/2023]
Abstract
BACKGROUND Tri-iodothyronine (T3) has been shown to be a hepatic mitogen. We investigated whether exogenous application of T3 improves liver regeneration after 70% partial hepatectomy (PH) and confers a survival advantage after 90% subtotal hepatectomy (SH) in rats and whether this is associated with the stimulation of angiogenesis. METHODS Rats were subjected to PH or SH 10 days after injection of a single dose of T3. Liver body weight ratio (LBR), hepatic proliferation (Ki-67), biochemical markers as well as vascular endothelial growth factor (VEGF) expression were assessed by immunohistochemistry. Gene expression of pathogenic relevant genes was determined by customized cDNA arrays and quantitative RT-PCR. RESULTS T3-treated rats showed an increased LBR and Ki-67 index after PH and SH, which reached statistical significance compared to placebo-treated rats (p < 0.05). On the transcriptional level, T3-treated rats had an increased expression of VEGF as demonstrated by immunohistochemistry, which was associated with a higher expression of its receptor Flt-1. CONCLUSIONS Exogenous administration of T3 ameliorates liver regeneration after 70% PH and 90% SH, possibly due to stimulation of angiogenesis. Therefore, its clinical use might be of interest due to its excellent general practicability.
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The in vitro effects of dehydroepiandrosterone on chondrocyte metabolism. Osteoarthritis Cartilage 2006; 14:238-49. [PMID: 16297642 DOI: 10.1016/j.joca.2005.09.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Accepted: 09/30/2005] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To investigate the in vitro effects of dehydroepiandrosterone (DHEA) on neonatal rat chondrocytes. DESIGN Chondrocytes isolated from neonatal rat cartilage were cultured in three-dimensionally agarose beads and were treated with DHEA. METHODS Primary culture of chondrocytes was harvested from newborn Wistar rats. The DHEA effects on chondrocyte activities were evaluated by analyzing chondrocyte proliferation, matrix protein synthesis, gene expressions of collagen, matrix metalloproteinase-1, -3 and -13 (MMP-1, -3 and -13), and cyclooxygenase-2 (COX-II), and protein synthesis of interleukin-6 (IL-6), prostaglandin E2 (PGE2) and tissue inhibitor of metalloproteinase-1 (TIMP-1). RESULTS The DHEA treatment did affect chondrocyte proliferation and glycosaminoglycan (GAG) synthesis. DHEA suppressed the expression of MMP-1, -3 and -13 genes and PGE2 protein synthesis enhanced by lipopolysaccharide (LPS) while the COX-II and inducible nitric oxide synthase (iNOS) gene expressions were down-regulated by DHEA. CONCLUSIONS Our study demonstrates that DHEA has an ability to modulate the imbalance between MMPs and PGE2 in the neonatal chondrocytes which suggest that it has a potential protective role against articular cartilage damage.
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Efficacy of erbB specific tyrosine kinase inhibitors in thyroid carcinoma cells. Exp Clin Endocrinol Diabetes 2006. [DOI: 10.1055/s-2006-932911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
Therapy related alterations to the thyroid gland are associated with more or less specific morphological changes. The therapy (thyrostatic drugs, radio-iodine) may be administered for the treatment of thyroid dysfunction (hyperthyroidism), or the thyroid gland is involved during or after the treatment (irradiation, various drugs) of primarily non-thyroid related diseases. The present review summarizes the most important morphological changes related to therapy.
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The C allele of theGNB3 C825T polymorphism of the G protein β3-subunit is associated with an increased risk for the development of oncocytic thyroid tumours. J Pathol 2006; 211:60-6. [PMID: 17136758 DOI: 10.1002/path.2084] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Carriers of the C allele of the common C825T polymorphism in the GNB3 gene of the G protein have been associated with the development of follicular thyroid adenomas. Since the C allele of this polymorphism is related to a lower signalling capacity, it was speculated whether the C825T polymorphism may play a particular role in oncocytic thyroid tumours, which are recognized for their reduced ability to synthesize thyroid-specific proteins and hormones, although they possess an intact thyroid-stimulating hormone receptor-adenylyl cyclase system. Using pyrosequencing, both the genotype distribution and the allele frequency of the C825T polymorphism were investigated in a series of 104 patients with oncocytic thyroid tumours of follicular cell origin [58 adenomas, 41 follicular thyroid carcinomas (FTCs), and five papillary thyroid carcinomas (PTCs)]; the results were compared with those obtained from 321 age and gender-matched healthy blood donors and a series of 327 non-oncocytic thyroid tumours of follicular cell origin (119 adenomas, 80 FTCs, and 186 PTCs). Analysis of the genotype distribution (comparing oncocytic with non-oncocytic tumours of the present series) revealed a significantly increased odds ratio (OR) for CC versus TT (OR = 4.22; p = 0.011) and CC versus CT (OR = 1.62; p = 0.049) carriers to develop an oncocytic thyroid tumour; ORs to develop an oncocytic thyroid tumour were also increased comparing the genotype distribution between the group of oncocytic tumours and healthy controls for CC versus TT (OR = 3.73; p = 0.017) and CC versus all T carriers (OR = 1.56; p = 0.034). Oncocytic thyroid tumours as a group showed a statistically significant increase of the C-allele frequency when compared with all non-oncocytic tumours (p = 0.0039) as well as healthy blood donors (p = 0.017). The results strongly suggest that the C allele of the GNB3 C825T polymorphism of the G protein beta3-subunit is associated with an increased risk for the development of oncocytic thyroid tumours. This polymorphism may thus be considered a (co)factor favouring the development of oncocytic thyroid tumours, although the biological mechanism(s) underlying this association remain obscure.
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Expression of IGF-1 receptors and GH receptors in thyroid tissue of patients with acromegaly. Exp Clin Endocrinol Diabetes 2005. [DOI: 10.1055/s-2005-863024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Efficacy of erbB specific tyrosine kinase inhibitors in thyroid carcinoma cells. Exp Clin Endocrinol Diabetes 2005. [DOI: 10.1055/s-2005-862950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Regulation of thyroid cells and thyroid tumors by the novel cAMP-binding protein Epac. Exp Clin Endocrinol Diabetes 2005. [DOI: 10.1055/s-2005-862933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Erdheim-Chester disease: case report with multisystemic manifestations including testes, thyroid, and lymph nodes, and a review of literature. J Clin Pathol 2004; 57:1225-8. [PMID: 15509691 PMCID: PMC1770491 DOI: 10.1136/jcp.2004.018481] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Erdheim-Chester disease is a rare non-Langerhans' cell histiocytosis with characteristic radiological and histological features. This entity is defined by a mononuclear infiltrate consisting of lipid laden, foamy histiocytes that stain positively for CD68. About half of those affected have extraskeletal manifestations, including involvement of the hypothalamus-pituitary axis, lung, heart, retroperitoneum, skin, liver, kidneys, spleen, and orbit. This report describes the case of a 50 year old white man who presented with hypogonadism and diabetes insipidus. At necropsy, extensive organ involvement was found, including the testes, thyroid, and lymph nodes. This is the first report of thyroid and lymph node infiltration in this disease. Because of the endocrinological symptoms, neurosarcoidosis and hypophysitis are important diseases in the differential diagnosis. This report also includes a review of the literature concerning rare organ manifestations and patients presenting primarily with similar symptoms.
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Immunohistochemical determination of somatostatin receptor subtypes 1, 2A, 3, 4, and 5 in various adrenal tumors. Endocr Res 2004; 30:931-4. [PMID: 15666847 DOI: 10.1081/erc-200044161] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
While octreotide binds with high affinity to sst2a only, the new analogue SOM230 demonstrates high affinity for sstl, 3, and 5, in addition. We examined the immunohistochemical expression of somatostatin receptor subtypes (sst) in 7 pheochromocytomas (PHEO), 5 Conn adenomas (CONN), 9 Cushing adenomas (CUSH), 7 nonfunctioning tumors (NFA), and 4 adrenal carcinomas (CA). About one third of the PHEO were positive for sst1, 2a, and 5. Less than 30% of cells were stained in the majority of these tumors. Each of the PHEO expressed sst3 with more than 60% of cells stained. Two thirds of the NFA revealed positive staining for sst1, 2a, and 3 with less than 30% of cells affected. Sst5 was expressed in nearly all of the NFA with positive staining in 30-60% of tumor cells. Nearly all CUSH and CONN were positive for the subtypes evaluated. In the majority of these tumors, less than 30% of cells were positively stained. Fifty percent of CA expressed sst2a and 3 with positive staining in 30-100% of cells. None of them expressed sst1. Somatostatin receptors are expressed in adrenal tumors with a tumor-specific distribution pattern. This may offer new diagnostic and therapeutic possibilities.
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Expression and mutation analysis of regulatory subunit Iα of protein kinase A in undifferentiated and anaplastic thyroid carcinoma. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-819071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Somatostatin receptor expression in thyroid carcinomas: implications for diagnostics and therapy. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-819320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Abstract
The vast majority of thyroid tumours are epithelial. In contrast to thyroid adenoma, which is a common tumour, thyroid carcinomas make up only 1% of all human malignancies. Routine pathology is regularly confronted with a differential diagnosis involving thyroid adenoma and carcinoma, as well as particular variants of these tumours. This paper deals with the standardised gross and histological examination, as well as the impact of immunohistochemistry and intraoperative frozen sections on thyroid pathology.
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Abstract
Hyperparathyroidism is mainly caused by hyperplasia or adenomas of the parathyroid glands. Formerly, the therapeutic strategy depended on the morphological diagnosis (preferentially already made intraoperatively by examination of frozen sections). Today, however, the extent of parathyroid surgery is in many cases guided both by substantial improvements in the preoperative clinical diagnosis as well as the intraoperatively determined decrease in the serum parathyroid hormone level. Nevertheless, the pathologist should be familiar with the differential diagnostic criteria of parathyroid hyperplasia, adenoma, and carcinoma.
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[Inflammatory diseases of the thyroid gland. Epidemiology, symptoms and morphology]. DER PATHOLOGE 2003; 24:339-47. [PMID: 12961022 DOI: 10.1007/s00292-003-0628-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Inflammation of the thyroid gland makes up approximately 20% of all thyroid diseases. According to the clinical course, thyroiditis has been subdivided into acute, subacute, and chronic forms. Recent classifications are based on the fact that the majority of thyroiditis cases have an autoimmune background. The most common form of this disease is autoimmune thyroiditis (AIT), with or without subclinical/manifest hypothyroidism; less common forms of autoimmune thyroiditis comprise subacute granulomatous (de Quervain's) thyroiditis, postpartum thyroiditis, silent ("painless") thyroiditis, and invasive-sclerosing thyroiditis (Riedel's thyroiditis). Non-autoimmune thyroiditis is very rare (acute suppurative thyroiditis, radiation thyroiditis). Thyroiditis is both clinically and morphologically an important differential diagnosis of thyroid tumours. The present paper deals with the epidemiology, clinical course, and morphology of thyroiditis, knowledge of which is essential for the examination of cytological and histological thyroid specimens.
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Abstract
Hyperplasia of the follicular epithelium (goitre) is the most common morphological change in the thyroid seen by the pathologist. The present paper deals with the aetiology, epidemiology and clinical features of thyroid hyperplasia and its differential diagnosis from thyroid adenoma. Neoplastic hyperplasia of the calcitonin-producing thyroid C cells gives rise to familial medullary carcinoma. The second part of the paper deals with the definition of neoplastic C cell hyperplasia and its discrimination from physiological C cell hyperplasia.
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Isocupressic acid blocks progesterone production from bovine luteal cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2003; 30:533-41. [PMID: 12568280 DOI: 10.1142/s0192415x02000508] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The needles of ponderosa pine (Pinus ponderosa Laws.) were reported to induce abortions when fed to late-term pregnant beef cows in North America. An in vivo study of pregnant cows suggested that isocupressic acid (IA) was the main abortifacient isolated from needles and bark of the pine. However, the mechanism of abortifacient activity of IA is not clear yet. In a pregnant cow, the corpus luteum of the ovary helps the maintenance of pregnancy by its progesterone production. This study involved the IA extracted from the root of the Taiwan cypress (Juniperus formosana) and used a frozen-thawed bovine luteal cell culture system to investigate the action of IA on progesterone production. Thawed bovine luteal cells (1 x 10(5) cells/ml/well) in M199 medium were cultured in 24-well culture plates at 37 degrees C in a 5% CO2 incubator. Ten ml of tested drugs, IA at 1 to 1000 ng/ml and/or ovine luteinizing hormone (oLH) at 1 to 100 ng/microl or 8-bromo-cyclic adenosine monophosphate (8-Br-cAMP) with 0.1-10 mM, were added into each well. After 4 hours of incubation, the media were harvested and assayed for progesterone by an enzyme immunoassay. Progesterone production from cells was the indicator used to evaluate the action of IA. All tested doses of IA significantly inhibited progesterone production in both basal and oLH stimulating conditions. Also those dosages inhibited cyclic adenosine-3',5'- monophosphate (cAMP) stimulation, suggesting a post-cAMP mechanism is involved in the IA action. We concluded that IA can induce pregnant cows to abort partly through blocking luteal function and may be identified as a new abortifacient chemical.
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Dynamic scaling theory for a tethered membrane in solution. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 63:061207. [PMID: 11415080 DOI: 10.1103/physreve.63.061207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2000] [Indexed: 05/23/2023]
Abstract
We present the dynamic scaling behavior for the specific viscosity and diffusion coefficient of a single membrane and membranes with nonzero concentration in solution. Starting from the membrane free energies, we derive their Langevin equations. The corresponding Kirkwood diffusion equation, describing the time evolution in configuration space, contains two kinds of time scales that are separated by the external dimension 4/(2-D) where D is the dimension of the internal space. These time scale separation behaviors depend strongly on the hydrodynamic screening effect. For a single membrane solution, we resolve the dynamic scaling exponents for the diffusion coefficient and intrinsic viscosity by the dimension reduction method. For a concentrated membrane solution, the effective excluded volume strength and draining parameter are introduced. The effective medium argument is applied to obtain a concentration dependent power law form for the specific viscosity and diffusion coefficient, whose results contribute to a fundamental understanding of membrane in solution and of hydrodynamic screening and excluded volume effects in many different solvents.
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Ginseng flowers stimulate progesterone production from bovine luteal cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2001; 28:371-7. [PMID: 11154050 DOI: 10.1142/s0192415x0000043x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Our previous report first showed evidence that polysaccharides isolated from ginseng leaves obtained from Jilin, China possess luteotropic activities. In this study, we made further investigations on the root and flowers of Korean ginseng by means of the same bioassay system described briefly as follows. Frozen-thawed bovine luteal cells (1 x 10(5) cells/ml/well) in M199 were incubated in 24-well culture plates at 37 degrees C in a 5 % CO2 incubator. Ten microl of tested drugs with 1, 10 and 100 microg/ml were added into each well. After 4- and 24-hr incubation, the media were harvested and assayed for progesterone by an enzyme immunoassay. The production of progesterone from cells is the indicator for evaluating the action of tested drugs. Results showed that hot water extracts ofginseng flowers (GF-1) with 10 to 100 microg/ml significantly increased progesterone production, whereas those from ginseng root (GR-1) could not. Crude polysaccharides (GF-2) isolated from GF-1 is the active component and the small molecules (mw < 10,000 dalton) are excluded, indicating that the ginseng root has no luteotropic activities, but the polysaccharides of ginseng flowers have.
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Simulation of the wiener sausage. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 62:3116-20. [PMID: 11088805 DOI: 10.1103/physreve.62.3116] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2000] [Indexed: 11/07/2022]
Abstract
The volume of a region visited by a spherical Brownian particle for a time t, known as the Wiener sausage, is an important random variable characterizing Brownian motion. A Brownian dynamics simulation is used to study statistical properties of the Wiener sausage volume. We show that the probability density is closely approximated by a Gaussian distribution not only at asymptotically long times, but over a wide range of times as well. We also refine the expression for the dispersion by finding a correction term for the long-time asymptotic dependence.
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Dynamical principles in biological processes: a model of charge migration in proteins and DNA. Proc Natl Acad Sci U S A 2000; 97:9849-54. [PMID: 10954730 PMCID: PMC27603 DOI: 10.1073/pnas.140196597] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The generalized master equations (GMEs) that contain multiple time scales have been derived quantum mechanically. The GME method has then been applied to a model of charge migration in proteins that invokes the hole hopping between local amino acid sites driven by the torsional motions of the floppy backbones. This model is then applied to analyze the experimental results for sequence-dependent long-range hole transport in DNA reported by Meggers et al. [Meggers, E., Michel-Beyerle, M. E., & Giese, B. (1998) J. Am. Chem. Soc. 120, 12950-12955]. The model has also been applied to analyze the experimental results of femtosecond dynamics of DNA-mediated electron transfer reported by Zewail and co-workers [Wan, C., Fiebig, T., Kelley, S. O., Treadway, C. R., Barton, J. K. & Zewail, A. H. (1999) Proc. Natl. Acad. Sci. USA 96, 6014-6019]. The initial events in the dynamics of protein folding have begun to attract attention. The GME obtained in this paper will be applicable to this problem.
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Trapping by clusters of traps. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 61:6302-7. [PMID: 11088304 DOI: 10.1103/physreve.61.6302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/1999] [Indexed: 04/15/2023]
Abstract
We study how the trapping kinetics is modified when traps are gathered in clusters. Recently, we have proposed a mean-field theory of trapping by clusters of traps valid at the initial stage of the process [J. Chem. Phys. 111, 711 (1999)]. Here by using the optimal-fluctuation method we incorporate fluctuation effects in the theory and discuss the manifestation of trap clustering in the kinetics over the entire time domain. Notable observations are that due to trap clustering (1) the trapping kinetics can be significantly modified from the very beginning of the process; (2) the fluctuation-induced kinetics exhibits more rich behavior; (3) the fraction of particles reacting according to a stretched-exponential law can be substantially increased.
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Charge conductivity in peptides: dynamic simulations of a bifunctional model supporting experimental data. Proc Natl Acad Sci U S A 2000; 97:1068-72. [PMID: 10655485 PMCID: PMC15524 DOI: 10.1073/pnas.97.3.1068] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Our previous finding and the given mechanism of charge and electron transfer in polypeptides are here integrated in a bifunctional model involving electronic charge transfer coupled to special internal rotations. Present molecular dynamics simulations that describe these motions in the chain result in the mean first passage times for the hopping process of an individual step. This "rest and fire" mechanism is formulated in detail-i.e., individual amino acids are weakly coupled and must first undergo alignment to reach the special strong coupling. This bifunctional model contains the essential features demanded by our prior experiments. The molecular dynamics results yield a mean first passage time distribution peaked at about 140 fs, in close agreement with our direct femtosecond measurements. In logic gate language this is a strongly conducting ON state resulting from small firing energies, the system otherwise being a quiescent OFF state. The observed time scale of about 200 fs provides confirmation of our simulations of transport, a model of extreme transduction efficiency. It explains the high efficiency of charge transport observed in polypeptides. We contend that the moderate speed of weak coupling is required in our model by the bifunctionality of peptides. This bifunctional mechanism agrees with our data and contains valuable features for a general model of long-range conductivity, final reactivity, and binding at a long distance.
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Involvement of protein kinase C-gamma in IL-1beta-induced cyclooxygenase-2 expression in human pulmonary epithelial cells. Mol Pharmacol 2000; 57:36-43. [PMID: 10617676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The signaling pathway of protein kinase C (PKC) is known to play a role in mediating the action of various cytokines. Here we examined the signal transduction pathway of PKC activation and the role of PKC isoforms in interleukin-1beta (IL-1beta)-mediated cyclooxygenase-2 (COX-2) expression in human pulmonary epithelial cell line (A549). The tyrosine kinase inhibitors (genistein and tyrphostin AG126) and phosphatidylcholine-phospholipase C inhibitor (D-609) prevented IL-1beta-induced prostaglandin E(2) (PGE(2)) release and COX-2 expression, whereas U-73122 (a phosphatidylinositol-phospholipase C inhibitor) and propranolol (a phosphatidate phosphohydrolase inhibitor) had no effect. The PKC inhibitors (Go 6976 and Ro 31-8220) and NF-kappaB inhibitor, pyrrolidine dithiocarbamate, also attenuated IL-1beta-induced PGE(2) release and COX-2 expression. Western blot analysis using PKC isoenzyme-specific antibodies indicated that A549 cells expressed PKC-alpha, -gamma, -iota, -lambda, -zeta, and -micro. IL-1beta caused the translocation of PKC-gamma but not other isoforms from cytosol to the membrane fraction. Moreover, the translocation of PKC-gamma was inhibited by genistein or D-609, but not by U-73122. IL-1beta caused the translocation of p65 NF-kappaB from cytosol to the nucleus as well as the degradation of IkappaB-alpha in cytosol. Furthermore, the translocation of p65 NF-kappaB was inhibited by genistein, Go 6976, Ro 31-8220, or pyrrolidine dithiocarbamate. These results indicate that in human pulmonary epithelial cells, IL-1beta might activate phosphatidylcholine-phospholipase C through an upstream tyrosine phosphorylation to elicit PKC activation, which in turn initiates NF-kappaB activation, and finally induces COX-2 expression and PGE(2) release. Of the PKC isoforms present in A549 cells, only activation of PKC-gamma is involved in regulating IL-1beta-induced responses.
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Abstract
Benzophenone is an ultraviolet (UV)-absorbing agent that has been used in industry and medicine for more than 30 years. Consumers of cosmetics and sunscreens containing UV-absorbers are exposed to benzophenones on a daily basis, owing to the widespread use of these compounds. However, the efficacy of these compounds as scavengers of oxidative stress is still not well established. In the present study, we investigate the antioxidative capacity of six sunscreen benzophenone compounds. A primary myoblast culture was mixed in vitro with 100 microM menadione. The cytotoxic effect by menadione-induced oxidative stress was monitored by the lucigenin- or luminol-amplified chemiluminescence, methylthiotetrazole (MTT) assay, and the antioxidative effects of various benzophenone compounds were evaluated. The results showed that the addition of menadione can induce oxidative stress on myoblasts by superoxide and hydrogen peroxide production, which can be eradicated by superoxide dismutase (SOD) and catalase, respectively, in a dose-dependent mode. The catalase has a protective effect on the cytotoxicity induced by menadione as measured by the MTT assay, while the SOD does not. The selected benzophenones also have a significant scavenging effect on the menadione-induced cell death on the myoblasts. The ortho-dihydroxyl structure and other hydroxy groups in the same ring have a stronger scavenging effect on the superoxide anion on myoblasts; thus, a stable penoxy radical may be formed. The mechanism of this effect remains to be clarified.
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Benzophenones as xanthine oxidase inhibitors. Anticancer Res 1999; 19:1131-5. [PMID: 10368664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Eight synthetic benzophenones were tested for their inhibitory effects on xanthine oxidase (XO). The enzyme, XO catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a lambda max of 295 nm, forming the basis for a spectrophotometric assay for the activity of XO. The results showed that 2,2',4,4'-tetrahydroxybenzophenone (6), 3,4,5,2',3',4'-hexahydroxybenzophenone (8) and 4,4'-dihydroxybenzophenone (3) displayed the inhibitory effects on XO with an order of activity of IC50 = 47.59, 69.40 and 82.94 microM, respectively. The apparent inhibition constants (Ki) of (8) and (3) were 15.61 and 64.86 microM respectively, and both of them induced mixed type (non-competitive-uncompetitive) inhibitions of the substrate xanthine.
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Expression of foreign antigens on the surface of Escherichia coli by fusion to the outer membrane protein traT. J Biomed Sci 1999; 6:64-70. [PMID: 9933744 DOI: 10.1007/bf02256425] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The traT gene is one of the F factor transfer genes and encodes an outer membrane protein which is involved in interactions between an Escherichia coli and its surroundings. This protein was altered so as to permit the expression of foreign proteins on the outer membrane of E. coli in this study. A 729-bp DNA fragment, including the leader and entire structural gene sequence of traT, was amplified and obtained by PCR. This sequence was then subcloned downstream of the tac promoter of pDR540, resulting in a TraT expression vector, pT2. Here, we report that the expression of TraT protein, fused either with a partial pre-S antigen of hepatitis B virus (60 and 98 amino acids, respectively) or with the snake venom rhodostomin (72 amino acids), was successfully achieved on the outer membrane of E. coli, using the pT2 plasmid. This result was demonstrated using dot blot and immunofluorescence analysis. This finding supports the notion that the pT2 plasmid can be used as an E. coli display system. This system can detect a foreign peptide of about 100 amino acid residues in length on the bacterial surface.
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Inhibition of xanthine oxidase by benzothiazinone analogues. Anticancer Res 1999; 19:119-23. [PMID: 10226532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Fourteen synthetic benzothiazinone analogues were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase (XO) catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a lambda max of 295 nm, forming the basis for a spectrophotometric assay for the activity of xanthine oxidase. The results showed that 2-amino-4H-1,3-benzothiazine-4-one (1), 2-guanidino-4H-1,3-benzothiazin-4-one (2) and rhodanine (3) display inhibitory effects on xanthine oxidase with an order of activity of IC50 = 5.54, 5.60 and 121.40 microM respectively. The apparent inhibition constants (Ki) were 5.12, 19.47 and 206.23 microM, and induced non-competitive, mixed type (non-competitive-uncompetitive) and mixed type (non-competitive-uncompetitive) inhibitions respectively with respect to the substrate xanthine.
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Inhibition of xanthine oxidase by purpurogallin and silymarin group. Anticancer Res 1998; 18:263-7. [PMID: 9568088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Thirteen phenolic compounds were tested for their inhibitory effects on xanthine oxidase. The enzyme xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has lambda max of 295 nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that purpurogallin and silymarin group displayed the inhibitory effects on xanthine oxidase (IC50 = 2.96 +/- 0.12 and 27.58 +/- 3.48 microM, respectively). Their apparent inhibition constants (Ki) were 1.16 and 5.85 microM, and induced uncompetitive and mixed type (non-competitive-uncompetitive) inhibitions respectively, with respect to the substrate xanthine.
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Superoxide anion scavenge effect of Quercus glauca Thunb. in whole blood of patients with ankylosing spondylitis. THE AMERICAN JOURNAL OF CHINESE MEDICINE 1997; 25:307-15. [PMID: 9358904 DOI: 10.1142/s0192415x97000342] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Nine phenolic compounds, catechin (1), epicatechin (2), gallocatechin (3), epigallocatechin (4), procyanidin B-4 (5), catechin-3-O-rhamnoside (6), rutin (7), querglanin (8) and isoquerglanin (9) were isolated from oak leaves (Quercus glauca Thunb. Fagaceae), and the latter two (8, 9) were identified as new compounds. Several Quercus species have been used in folk medicine as an astringent for hemorrhoids and for treatment of inflammation, jaundice, and tumor. In this study, these compounds were tested for scavenging effects of the superoxide anion in the whole blood of patients with ankylosing spondylitis by means of an ultra-sensitive chemoluminescence (CL) analyzer and lucigenin amplification. The results showed that at a concentration of 2.3 x 10(-5) M, isoquerglanin (9) displayed the strongest inhibition activity (73.55%), followed by querglanin (8) (68.81%) and then gallocatechin (3) and epigallocatechin (4) (66.97 and 60.17% inhibition, respectively). In addition, the blood chemoluminescence (CL) level of patients with ankylosing spondylitis was inhibited by superoxide dismutase (SOD) but not by catalase, suggesting that superoxide anion is the major component of reactive oxygen species (ROS) involved in this assay system.
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Inhibition of xanthine oxidase by hydroxylated anthraquinones and related compounds. Anticancer Res 1997; 17:3293-7. [PMID: 9413162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Eighteen anthraquinones and related compounds were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a lambda max of 295nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that anthrarobin and purpurin showed moderate effects on xanthine oxidase inhibition (IC50 = 68.35 and 105.13 microM; Ki = 122.38 and 130.49 microM respectively), and both of them induced mixed type (competitive-non-competitive) inhibition with respect to the substrate xanthine.
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Inhibition of xanthine oxidase by synthetic cytokinin analogues. Anticancer Res 1997; 17:1043-9. [PMID: 9137447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Thirteen synthetic cytokinin analogues were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a gamma max of 295 nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that 8-azaadenine(1), 4-amino-6-hydroxypyrazolo [3,4-d] pyrimidine(4), 4-amino-6-mercaptopyrazolo [3,4-d] pyrimidine(5) and 4-aminopyrazolo [3,4-d] pyrimidine(6) display inhibitory effects on xanthine oxidase with an order of activity of IC50 = 0.54, 5.91, 8.17 and 25.46 microM, respectively. Their apparent inhibition constants (Ki) were 0.66, 1.54, 6.61 and 26.79 microM, and induced mixed(competitive-non-competitive), competitive, mixed (competitive-non-competitive), and competitive types of inhibition respectively, with respect to the substrate xanthine.
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Inhibition of xanthine oxidase by cytokinins and related substances. Anticancer Res 1996; 16:3571-6. [PMID: 9042223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Fourteen cytokinins were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid which has lambda max of 295 nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that adenine-HCl, N6-(2-isopentenyl)-adenine, purine and DL-dihydrozeatin displayed very potent activities (IC50 = 1.92, 10.99, 60.98 and 86.36 microM respectively). Their apparent inhibition constants (Ki) were 2.20, 17.99, 13.59 and 115.62 microM, and induced competitive, uncompetitive, competitive and non-competitive type inhibitions respectively with respect to the substrate xanthine.
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Stochastic gating in diffusion-influenced ligand binding to proteins: Gated protein versus gated ligands. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:4462-4464. [PMID: 9965605 DOI: 10.1103/physreve.54.4462] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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