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D S Kim

Publications and source records attributed to D S Kim.

At least 19 recordsLinked to original sources

Securin induces genetic instability in colorectal cancer by inhibiting double-stranded DNA repair activity.

Genetic instability (GI) is a hallmark feature of tumor development. Securin, also known as pituitary tumor transforming gene (PTTG), is a mitotic checkpoint protein which is highly expressed in numerous cancers, is associated with tumor invasiveness, and induces GI in thyroid cells. We used fluorescence inter-simple sequence repeat PCR to assess GI caused primarily by DNA breakage events in 19 colorectal tumors. GI values ranged significantly, with Dukes' stage C&D colorectal tumors exhibiting greater GI and higher securin expression than Dukes' stage A&B tumors. Consistent with these findings, we observed a dose-dependent increase in GI in HCT116 cells in response to securin overexpression, as well as in non-transformed human fibroblasts. As securin has been implicated in a novel DNA repair pathway in fission yeast, we investigated its potential role in chemotoxic DNA damage response pathways in mammalian cells, using host cell reactivation assays. Securin overexpression in HCT116 cells inhibited etoposide-induced double-stranded DNA damage repair activity, and repressed Ku heterodimer function. Additionally, we observed that securin and Ku70 showed a reciprocal cytosol-nuclear translocation in response to etoposide-induced dsDNA damage. Our data suggest that, by repressing Ku70 activity and inhibiting the non-homologous end-joining dsDNA repair pathway, securin may be a critical gene in the development of GI in colorectal cancer.

Animals↗

Pituitary tumor transforming gene (PTTG) stimulates thyroid cell proliferation via a vascular endothelial growth factor/kinase insert domain receptor/inhibitor of DNA binding-3 autocrine pathway.

CONTEXT: Vascular endothelial growth factor (VEGF) exerts its biological effects by binding to the tyrosine kinase receptors VEGF receptor type 1 (VEGFR1/Flt-1) and VEGFR2 (Flk-1/KDR). Kinase insert domain receptor (KDR) is the critical receptor controlling proliferation and migration of endothelial cells and has been shown to be expressed in some nonendothelial cells. We recently reported that the proangiogenic pituitary tumor transforming gene (PTTG) stimulates VEGF and up-regulates inhibitor of DNA binding-3 (ID3), an important gene in VEGF-dependent angiogenesis. OBJECTIVE: Our objective was to test whether VEGF, ID3, and KDR confer a PTTG-mediated effect on thyroid cell growth. DESIGN: Gene expression, MAPK stimulation, and cell proliferation were assessed in follicular thyroid cancer FTC133 cells. Gene expression and clinical associations were determined in 21 normal and 38 tumorous thyroid specimens (nine follicular and 29 papillary). RESULTS: ID3 correlated with VEGF mRNA expression in our series of thyroid cancers, which also showed up-regulated KDR mRNA. Stimulation of FTC133 cells with exogenous VEGF enhanced ID3 expression, which could be abrogated by the KDR-specific inhibitor ZM323881, suggesting that VEGF regulation of ID3 is KDR dependent. PTTG significantly correlated with KDR mRNA expression in our thyroid cancer cohort and up-regulated KDR and VEGF expression in FTC133 cells. Finally, cells transfected with PTTG demonstrated increased cell proliferation and phosphorylation of MAPK, which was abrogated by ZM323881. CONCLUSIONS: We report the presence of a VEGF/KDR/ID3-dependent autocrine pathway in FTC133 thyroid cells. By up-regulating both VEGF and KDR expression, we propose a novel PTTG-mediated proliferative pathway that may be critical to thyroid cancer growth and progression.

Adenocarcinoma, Follicular↗

The metallic composition of aerosols at three monitoring sites in Korea during winter 2002.

In the present study, the distribution patterns of various metals were analyzed and compared using PM samples collected concurrently from three monitoring sites located in Korea (Seoul, Busan, and Jeju island) in December 2002. As these sites can represent metal pollution with different degrees of anthropogenic activities, their concentration levels were distinguished in a systematic manner in the order of Jeju, Busan, and Seoul. By comparing the present data sets with those measured previously from other locations in Korea and around the world, we attempted to diagnose the general status of elemental pollution on the Korean peninsula. Through an application of different statistical approaches, the major processes controlling elemental levels were assessed for each of the three study sites. The results indicated the importance of both crustal and anthropogenic sources in all sites with their relative roles varying significantly from each other. The results of the metal analysis data, when examined in relation to back trajectory analysis, confirmed that their concentration changes are affected quite sensitively with air mass movement patterns. The overall results of this study consistently indicated the contribution of a strong anthropogenic source area (e.g., China) to the observed metal concentration levels in the study area, but the strengths of such signals vary considerably across the Korean peninsula.

Aerosols↗

Comparison of two commercial interferon-gamma assays for diagnosing Mycobacterium tuberculosis infection.

The clinical usefulness of ex vivo interferon-gamma assays may largely depend on the assay format and epidemiological status of tuberculosis (TB) in the region studied. From July 2004 to June 2005 a prospective comparison study was undertaken at a tertiary referral hospital in South Korea. The results of tuberculin skin tests (TST) and the commercially available QuantiFERON-TB Gold (QFT-G) and T SPOT-TB (SPOT) assays were compared in an intermediate TB-burden country. Of the 224 participants studied, results from all three tests (TST, QFT-G, and SPOT) were available in 218; 87 with active TB and 131 at a low risk for TB. Using 10 mm as a cut-off for TST, SPOT sensitivity (96.6%) was significantly higher than that seen for TST (66.7%) and QFT-G (70.1%). QFT-G showed superior specificity over TST (91.6 versus 78.6%). Although the specificity of QFT-G was higher than that of SPOT (91.6 versus 84.7%), the difference was not statistically significant. Whilst some differences were found in the performance of the two commercialised interferon-gamma assays, they seemed to be superior in their detection of Mycobacterium tuberculosis infection compared with tuberculin skin tests. The most appropriate choice of interferon-gamma assay to use may depend on the clinical setting.

Adolescent↗

Reversal of supersensitive striatal dopamine D1 receptor signaling and extracellular signal-regulated kinase activity in dopamine-deficient mice.

Lesions of dopaminergic nigrostriatal neurons cause supersensitivity to dopamine in the striatum. Previous work has shown that such supersensitivity, an important aspect of rodent models of Parkinson's disease, is associated with anatomically abnormal patterns in the activation of extracellular signal-regulated kinase. After lesions of dopaminergic neurons, dopamine D1-receptor agonists activate extracellular signal-regulated kinase in the dorsal striatum, something not observed in intact animals. Here we used a more selective method of dopamine depletion. Dopamine-deficient mice, in which the tyrosine hydroxylase gene is specifically inactivated in dopaminergic neurons, were used to investigate dopamine D1-receptor-mediated activation of extracellular signal-regulated kinase. In wild-type mice, acute treatment with a dopamine D1-receptor agonist results in activation of extracellular signal-regulated kinase in the nucleus accumbens without activation in the dorsal striatum. In contrast, in dopamine-deficient mice, dopamine D1-receptor-agonist treatment results in activation of extracellular signal-regulated kinase not only in the nucleus accumbens, but also throughout most of the dorsal striatum. Chronic replacement of dopamine by repeated injection of L-DOPA for 36 h reverses this supersensitive extracellular signal-regulated kinase activation. This reversal displays a dorsal to ventral progression such that, by 36 h, extracellular signal-regulated kinase activation is virtually restricted to the nucleus accumbens, as in wild-type mice. The reversal of dopamine D1-receptor activation of extracellular signal-regulated kinase in dopamine-deficient mice following chronic L-DOPA treatment shows that the lack of dopamine, rather than absence of other factors secreted from dopaminergic neurons, is responsible for dopamine supersensitivity.

Animals↗

Pituitary tumor-transforming gene regulates multiple downstream angiogenic genes in thyroid cancer.

CONTEXT: Pituitary tumor-transforming gene (PTTG) is a multifunctional protein involved in several tumorigenic mechanisms, including angiogenesis. PTTG has been shown to promote angiogenesis, a key rate-limiting step in tumor progression, by up-regulation of fibroblast growth factor-2 and vascular endothelial growth factor. OBJECTIVE: To investigate whether PTTG regulates other angiogenic genes in thyroid cells, we performed angiogenesis-specific cDNA arrays after PTTG transfection. Two of the genes [inhibitor of DNA binding-3 (ID3) and thrombospondin-1 (TSP-1)] which showed differential expression in primary thyroid cells were validated in vitro and in vivo. RESULTS: TSP-1 showed a 2.5-fold reduction and ID3 showed a 3.5-fold induction in expression in response to PTTG overexpression in vitro. Conversely, suppression of PTTG with small interfering RNA was associated with a 2-fold induction of TSP-1 and a 2.2-fold reduction in ID3 expression. When we examined TSP-1 and ID3 expression in 34 differentiated thyroid cancers, ID3 was significantly increased in tumors compared with normal thyroid tissue. Furthermore, ID3 expression was significantly higher in follicular thyroid tumors than in papillary tumors. Although mean TSP-1 expression was not altered in cancers compared with normal thyroids, we observed a significant independent association between TSP-1 expression and early tumor recurrence, with recurrent tumors demonstrating 4.2-fold lower TSP-1 expression than normal thyroid tissues. CONCLUSION: We have identified ID3 and TSP-1 as two new downstream targets of PTTG in thyroid cancer. We propose that PTTG may promote angiogenesis by regulating the expression of multiple genes with both pro- and antiangiogenic properties and may thus be a key gene in triggering the angiogenic switch in thyroid tumorigenesis.

Cell Line, Tumor↗

Suitable whole blood levels 2 hours after neoral in liver transplant patients: experiences at a single center.

UNLABELLED: Whole blood levels 2 hours after Neoral (C2) administration were observed to correlate better with area under the curve (AUC(0-4)) than trough levels (C0), suggesting that C2 may be the best single time point predictor of Neoral absorption. Owing to concerns about drug toxicity due to excessive immunosuppression, C2 adjustments to target blood levels may represent an advance. The present study measured C2 and levels to determine which correlated more closely with AUC(0-4). METHODS: Between August 2003 and July 2004, 40 adult liver transplantations were performed in our center. All patients received Neoral twice daily. They were maintained at a C0 level of about 200 ng/mL. C0 levels were measured daily. C2 levels were estimated on postoperative days 3, 5, 7, 14, and 28. AUC(0-4) performed on postoperative days 3, 7, and 28 was calculated using the trapezoidal rule. RESULTS: The mean AUC(0-4), C0, C1, C2, C3, and C4 were 1100.3 +/- 484.8 ng/mL, 197.1 +/- 84.7 ng/mL, 240.7 +/- 166.2 ng/mL, 307.8 +/- 162.6 ng/mL, 302.8 +/- 138.9 ng/mL, and 300.3 +/- 142.8 ng/mL, respectively. C2 correlated with AUC(0-4) (R2 = 0.868: P < .05) better than C0 (R2 = 0.245: P < .05), C1 (R2 = 0.604: P < .05), or C4 (R2 = 0.583: P < .05). CONCLUSIONS: Neoral dose monitoring according to a mean C2 range of 307.8 +/- 162.6 ng/mL correlated better with AUC(0-4). Further studies are required to determine suitable C2 levels in liver transplant patients.

Adult↗

Inhibition of angiogenesis and tumor progression by hydrodynamic cotransfection of angiostatin K1-3, endostatin, and saxatilin genes.

In vivo expression of angiostatin and endostatin, two different types of endothelial cell growth inhibitor, have been reported to inhibit vascularization in tumor tissues, resulting in tumor growth inhibition. Recently, in vivo expression of saxatilin, a novel disintegrin purified from snake (Gloydius saxatilis) venom, was able to strongly inhibit endothelial cell proliferation and smooth muscle cell migration, resulting in tumor growth inhibition. However, the antitumor efficacy of the individual antiangiogenic molecules expressed in vivo was not sufficiently potent to induce tumor regression in animal models. Therefore, in this study, we have systemically examined how combinational transfer of angiostatin, endostatin, and saxatilin genes affects neovascularization in tumor tissues and tumor progression in a mouse model. In Matrigel-implanted mice, cotransfection with plasmids encoding angiostatin K1-3 (pFLAG-Angio K1/3), endostatin (pFLAG-Endo), and saxatilin (pFLAG-Sax) resulted in the most effective inhibition of angiogenesis. In addition, hydrodynamic cotransfection of the three genes induced more inhibition of B16BL6 melanoma growth and pulmonary metastasis than other combinations of transfected genes. Compared with the empty vector-treated control group, cotreatment with the three plasmids reduced B16BL6 tumor growth by 89% and pulmonary metastasis by 90%. These results provide additional evidence supporting the combined systemic expression of antiangiogenic factors, such as angiostatin K1-3, endostatin, and saxatilin, as an alternative procedure for antiangiogenic cancer therapy.

Angiogenesis Inhibitors↗

Acute exacerbation of idiopathic pulmonary fibrosis: frequency and clinical features.

Although acute exacerbations of idiopathic pulmonary fibrosis are well recognised, there are no studies documenting their prevalence or identifying pre-existing risk factors. This study analysed the clinical, radiological and pathological data of 11 patients who satisfied the criteria for acute exacerbation among 147 patients with biopsy-proven idiopathic pulmonary fibrosis. There were five additional patients who had similar demographics, radiology and surgical lung biopsy pathology, but had clinically less severe disease, and so were not included. The 2-yr frequency of acute exacerbation was 9.6% after the diagnosis. Most exacerbations were idiopathic, although two cases presented after surgical lung biopsy and one after bronchoalveolar lavage. No significant risk factor was found by univariate proportional hazard analysis. Imaging revealed diffuse bilateral ground-glass opacification superimposed on subpleural reticular and honeycombing densities. The biopsies of four patients taken during acute exacerbation exhibited diffuse alveolar damage superimposed upon usual interstitial pneumonia. The findings of this study demonstrate that acute exacerbation of idiopathic pulmonary fibrosis is rather common and this exacerbation is likely to have a spectrum of severity.

Acute Disease↗

Influence of NICE guidelines on removal of third molars in a region of the UK.

We investigated compliance in the West Midlands, UK with the guidelines issued by the National Institute of Clinical Excellence (NICE) on the indications for the removal of third molars. We audited the practice at three departments of maxillofacial surgery that take referrals from three districts of the West Midlands. Of a total of 300 referral letters 217 (72%) specified a NICE-compliant diagnosis. A total of 267 patients (89%) were advised to have third molars removed and all three units achieved 100% compliance with NICE guidelines. There was a concordance of diagnosis of 69% between referring general dental practitioners and attending oral surgeons (concordance was 79% if only those referral letters that carried a specific indication were considered). Disease-free wisdom teeth made up a mean of only 6% of all referrals.

Dental Audit↗

Extreme conformational diversity in human telomeric DNA.

DNA with tandem repeats of guanines folds into G-quadruplexes made of a stack of G-quartets. In vitro, G-quadruplex formation inhibits telomere extension, and POT1 binding to the single-stranded telomeric DNA enhances telomerase activity by disrupting the G-quadruplex structure, highlighting the potential importance of the G-quadruplex structure in regulating telomere length in vivo. We have used single-molecule spectroscopy to probe the dynamics of human telomeric DNA. Three conformations were observed in potassium solution, one unfolded and two folded, and each conformation could be further divided into two species, long-lived and short-lived, based on lifetimes of minutes vs. seconds. Vesicle encapsulation studies suggest that the total of six states detected here is intrinsic to the DNA. Folding was severely hindered by replacing a single guanine, showing only the shortlived species. The long-lived folded states are dominant in physiologically relevant conditions and probably correspond to the parallel and antiparallel G-quadruplexes seen in high-resolution structural studies. Although rare under these conditions, the short-lived species determine the overall dynamics because they bridge the different long-lived species. We propose that these previously unobserved transient states represent the early and late intermediates toward the formation of stable G-quadruplexes. The major compaction occurs between the early and late intermediates, and it is possible that local rearrangements are sufficient in locking the late intermediates into the stably folded forms. The extremely diverse conformations of the human telomeric DNA may have mechanistic implications for the proteins and drugs that recognize G-rich sequences.

DNA↗

Femtosecond light transmission and subradiant damping in plasmonic crystals.

We report the first observation of subradiance in plasmonic nanocrystals. Amplitude- and phase-resolved ultrafast transmission experiments directly reveal the coherent coupling between surface plasmon polaritons (SPPs) induced by periodic variations in the dielectric function. This interaction results in the formation of plasmonic band gaps and coupled SPP eigenmodes with different symmetries, as directly shown by near-field imaging. In antisymmetric modes, radiative SPP damping is strongly suppressed, increasing the SPP lifetime from 30 fs to more than 200 fs. The findings are analyzed within a coupled resonance model.

Journal Article↗

Characterization of the altered anthranilate synthase in 5-methyltryptophan-resistant rice mutants.

In an earlier investigation, homologous mutant lines resistant to growth inhibition by 5-methyltryptophan (5MT) were selected from a callus that had been irradiated with a 50-Gy gamma ray during embryo culture. In order to identify the 5MT-resistant mechanism, we have continued our investigations of these mutant lines and studied the anthranilate synthase activity of the M5) advanced lines by direct fluorometric detection of the anthranilate formed in both control plants and mutant lines grown on 500 microM 5MT. The anthranilate synthase activity of the mutant plants was 2.2- to 3-fold higher than that of the control. In a kinetic analysis with tryptophan, an anthranilate synthase of the mutant lines was insensitive to feedback inhibition. These lines showed an enhanced accumulation of storage proteins and amino acids. The increased rates of protein synthesis in the mutant lines, relative to that of the control seeds, were 17-28.5%. The amino acid contents were 2.4-fold (MRI-40-2) to 2.6-fold (MRI-110-6) higher in the MRI lines than in the control seeds, and 2.4-fold (MRII-12-5) to 3.5-fold (MRII-8-1) higher in the MRII lines than in the control seeds. Significant increases among the amino acids of the MR lines were observed for tryptophan, phenylalanine, and tyrosine, which had been biosynthesized through the shikimate pathway. The transcript levels of putative OASA2, which is one of the key-regulating enzyme subunits in the tryptophan biosynthesis pathway, were studied in the control and 5MT-resistant mutant lines subjected to inhibition by two tryptophan analogs (5MT and alphaMT) and to other abiotic stresses (ABA, NaCl, and cold). The putative OASA2 gene in the 5MT-resistant mutant lines was highly expressed in at a low 5MT concentration and at an early stage of the 5MT and alphaMT treatments. However, mRNA accumulation of the putative OASA2 gene in the mutant plants gradually decreased when the plants were subjected to abiotic stresses such as NaCl and cold. These results indicated that the 5MT resistance in the mutant lines is due to altered anthranilate synthase forms.

Amino Acids↗

Ascorbate attenuates trimethyltin-induced oxidative burden and neuronal degeneration in the rat hippocampus by maintaining glutathione homeostasis.

The specific role of endogenous glutathione in response to neuronal degeneration induced by trimethyltin (TMT) in the hippocampus was examined in rats. A single injection of TMT (8 mg/kg, i.p.) produced a rapid increase in the formation of hydroxyl radical and in the levels of malondialdehyde (MDA) and protein carbonyl. TMT-induced seizure activity significantly increased after this initial oxidative stress, and remained elevated for up to 2 weeks post-TMT. Although a significant loss of hippocampal Cornus Ammonis CA1, CA3 and CA4 neurons was observed at 3 weeks post-TMT, the elevation in the level of hydroxyl radicals, MDA, and protein carbonyl had returned to near-control levels at that time. In contrast, the ratio of reduced to oxidized glutathione remained significantly decreased at 3 weeks post-TMT, and the glutathione-like immunoreactivity of the pyramidal neurons was decreased. However glutathione-positive glia-like cells proliferated mainly in the CA1, CA3, and CA4 sectors and were intensely immunoreactive. Double labeling demonstrated the co-localization of glutathione-immunoreactive glia-like cells and reactive astrocytes, as indicated by immunostaining for glial fibrillary acidic protein. This suggests that astroglial cells were mobilized to synthesize glutathione in response to the TMT insult. The TMT-induced changes in glutathione-like immunoreactivity appear to be concurrent with changes in the expression levels of glutathione peroxidase and glutathione reductase. Ascorbate treatment significantly attenuated TMT-induced seizures, as well as the initial oxidative stress, impaired glutathione homeostasis, and neuronal degeneration in a dose-dependent manner. These results suggest that ascorbate is an effective neuroprotectant against TMT. The initial oxidative burden induced by TMT may be a causal factor in the generation of seizures, prolonged disturbance of endogenous glutathione homeostasis, and consequent neuronal degeneration.

Animals↗

Comparison of early and delayed quantified indices of double-phase (99m)Tc MIBI scintimammography in the detection of primary breast cancer.

PURPOSE: To compare the diagnostic accuracy and incremental diagnostic role of quantitative indices of early and delayed lesion to non-lesion ratios (L/Ns) in the detection of primary breast cancer. MATERIAL AND METHODS: Double-phase (99m)Tc MIBI scintimammography (SMM) (early 10 min, delayed 3 h) was performed after injection of 750 MBq of (99m)Tc MIBI in 446 highly suspected breast cancer patients (malignant: 311, benign: 135). For visual analysis, five scoring methods were used, and, for quantitative analysis, early and delayed L/Ns were calculated. Receiver operating characteristic curve (ROC) analyses were performed to determine the optimal visual grade, and to calculate cut-off values of quantitative indices for differentiation of malignant and benign diseases and to investigate whether the quantitative indices could provide incremental diagnostic values in addition to visual analysis. RESULTS: Optimal visual grades were above 4 and 5 in the detection of breast cancer. Sensitivity was 84.2% and specificity 79.3%; the area under the curve (AUC) was 0.832 (95% CI, 0.794-0.866) and standard error was 0.019. Early and delayed L/Ns of malignant breast disease were significantly higher than those of benign disease (early: 2.01 +/- 0.99 versus 1.13 +/- 0.26 (P < 0.001); delayed: 1.68 +/- 0.69 versus 1.11 +/- 0.23 (P < 0.001)). The optimal L/Ns for the detection of primary breast cancer were 1.27 for early and 1.12 for delayed imaging. When early L/N 1.27 was used as cut-off value for the detection of primary breast cancer, the sensitivity of SMM was 77.8% and specificity 85.2%. The AUC was 0.856 (95% CI, 0.820-0.888). When delayed L/N 1.12 was used, sensitivity and specificity were 81.4% and 78.5%, respectively. The AUC was 0.834 (95% CI, 0.796-0.867). The ROC comparison of early and delayed L/N showed no statistical difference in the detection of malignant breast disease (P=0.403). When the delayed L/N was added to the early one, early plus delayed quantitative analysis (E+D) showed 86.5% sensitivity and 74.8% specificity. However, the AUCs of E+D (0.854, 95% CI, 0.767-0.842) and early L/N (E) (0.856) showed no statistical difference (P=0.614). When grades 4 and 5 were used as cut-off visual grade, sensitivity and specificity were 84.2% and 79.3%, respectively. When the E was added to visual grade, visual plus early L/N (V+E) showed 89.4% sensitivity and 77% specificity. The AUC of V+E (0.867, 95% CI, 0.832 0.897) was significantly higher than that of visual analysis (V) (0.832, 95% CI, 0.794-0.866, P < 0.001). When the delayed L/N (D) was added to visual grade, visual plus delayed L/N (V+D) showed 89.4% sensitivity and 74.1% specificity. The AUCs of V+D (0.852, 95% CI, 0.816-0.884) and V revealed no statistical differences (P = 0.052). CONCLUSION: From this study, the optimal visual grades for diagnosis of breast cancer were grades 4 and 5; the cut-off values of L/Ns were 1.27 for early and 1.12 for delayed imaging. It was also found that early L/Ns provide incremental value in addition to visual analysis. However, delayed L/N revealed no incremental value. Therefore, the delayed image should not be routinely performed for purposes of primary breast cancer detection

Adult↗

Characteristics of submucosal gastric carcinoma with lymph node metastatic disease.

AIM: To study the correlation between lymph node metastatic disease and various pathological parameters. Lymph node metastasis is the most important factor in determining the prognosis of patients with early gastric cancer and is significantly associated with the submucosal invasion of neoplastic cells. However, the depth of submucosal layer as well as the depth of submucosal tumour invasion varies among different cases. METHODS AND RESULTS: We studied various pathological parameters including the macroscopic appearance, location, size, area, differentiation, invasion depth, vascularity and fibrosis of submucosal gastric carcinomas (SMGC), using 248 age- and sex-matched tissue samples. The presence of lymphatic emboli, a larger area, greater size, a non-flat gross type and an increased vascularity of the tumour were significantly associated with node-positive SMGC. Among the three depth-related parameters, the ocular scale measurement, the sm3 method and the sm2 method, only the ocular scale measurement showed a significant correlation with node-positive SMGC. Using multivariate analysis, the incidence of lymph node metastasis increased in the lymphatic tumour emboli and in the tumours that invaded more than half of the submucosal layer. CONCLUSIONS: These histological indicators seem to be a feasible and easy way to predict lymph node metastatic disease from limited surgery specimens. Pathologists should carefully investigate the lymphatic invasion of tumour cells and measure the invasion depth of the tumour.

Adult↗

Comparative study on calretinin immunoreactivity in gerbil and rat retina.

Expression of calretinin in retina has been ascribed to multiple biological and functional aspects in the visual system. In this study, we examined the distribution patterns of calretinin immunoreactivity in gerbil and rat retina. In the gerbil, calretinin immunoreactivity was present in bipolar and amacrine cells of the inner nuclear layer and in neurones of the ganglion cell layer. In the rat, amacrine and ganglion cells showed calretinin immunoreactivity, but bipolar cells did not contain calretinin immunoreactivity. In both species, calretinin immunoreactivity was absent in cones, cone bipolars, and horizontal cells. In conclusion, gerbil as well as rat has a rod-dominant retina. The differences in calretinin expression between rat and gerbil require further investigations under various functional and developmental conditions.

Animals↗