Diabetes, Edentulism, and Cognitive Decline: A 12-Year Prospective Analysis.

Diabetes mellitus (DM) is a recognized risk factor for dementia, and increasing evidence shows that tooth loss is associated with cognitive impairment and dementia. However, the effect of the co-occurrence of DM and edentulism on cognitive decline is understudied. This 12-y cohort study aimed to assess the effect of the co-occurrence of DM and edentulism on cognitive decline and examine whether the effect differs by age group. Data were drawn from the 2006 to 2018 Health and Retirement Study. The study sample included 5,440 older adults aged 65 to 74 y, 3,300 aged 75 to 84 y, and 1,208 aged 85 y or older. Linear mixed-effect regression was employed to model the rates of cognitive decline stratified by age cohorts. Compared with their counterparts with neither DM nor edentulism at baseline, older adults aged 65 to 74 y (ß = -1.12; 95% confidence interval [CI], -1.56 to -0.65; P < 0.001) and those aged 75 to 84 y with both conditions (ß = -1.35; 95% CI, -2.09 to -0.61; P < 0.001) had a worse cognitive function. For the rate of cognitive decline, compared to those with neither condition from the same age cohort, older adults aged 65 to 74 y with both conditions declined at a higher rate (ß = -0.15; 95% CI, -0.20 to -0.10; P < 0.001). Having DM alone led to an accelerated cognitive decline in older adults aged 65 to 74 y (ß = -0.09; 95% CI, -0.13 to -0.05; P < 0.001); having edentulism alone led to an accelerated decline in older adults aged 65 to 74 y (ß = -0.13; 95% CI, -0.17 to -0.08; P < 0.001) and older adults aged 75 to 84 (ß = -0.10; 95% CI, -0.17 to -0.03; P < 0.01). Our study finds the co-occurrence of DM and edentulism led to a worse cognitive function and a faster cognitive decline in older adults aged 65 to 74 y.

Radiological diagnosis of drop metastases from paediatric brain tumours using combination of 2D and 3D MRI sequences.

AIM: To evaluate spinal magnetic resonance imaging (MRI) examinations using a combination of two-dimensional (2D) and three-dimensional (3D) MRI sequences for diagnosis of drop metastases. MATERIALS AND METHODS: Fifty-five paediatric patients with primary brain tumours were evaluated for drop metastases at initial presentation using spinal MRI including sagittal 2D T1-weighted (W) contrast-enhanced (+C), axial 3D T1W+C volumetric interpolated breath-hold (VIBE), and sagittal 3D T2W SPACE (Sampling Perfection with Application optimised Contrasts using different flip angle Evolutions). RESULTS: The MRI false-negative rate was 4%, and cerebrospinal fluid (CSF) false-negative rate was 16% (p=0.07). The 3D T1W+C VIBE increased the number of drop metastases detected in 42% of patients. Drop metastases were more conspicuous in 25% of patients on 3D T2W SPACE. CONCLUSION: Spinal MRI examinations including 2D and 3D sequences demonstrate characteristics that may improve radiological diagnosis of drop metastases.

Contrast Leakage Patterns from Dynamic Susceptibility Contrast Perfusion MRI in the Grading of Primary Pediatric Brain Tumors.

BACKGROUND AND PURPOSE: The pattern of contrast leakage from DSC tissue signal intensity time curves have shown utility in distinguishing adult brain neoplasms, but has limited description in the literature for pediatric brain tumors. The purpose of this study is to evaluate the utility of grading pediatric brain tumors with this technique. MATERIALS AND METHODS: A retrospective review of tissue signal-intensity time curves from 63 pediatric brain tumors with preoperative DSC perfusion MR imaging was performed independently by 2 neuroradiologists. Tissue signal-intensity time curves were generated from ROIs placed in the highest perceived tumor relative CBV. The postbolus portion of the curve was independently classified as returning to baseline, continuing above baseline (T1-dominant contrast leakage), or failing to return to baseline (T2*-dominant contrast leakage). Interobserver agreement of curve classification was evaluated by using the Cohen κ. A consensus classification of curve type was obtained in discrepant cases, and the consensus classification was compared with tumor histology and World Health Organization grade. RESULTS: Tissue signal-intensity time curve classification concordance was 0.69 (95% CI, 0.54-0.84) overall and 0.79 (95% CI, 0.59-0.91) for a T1-dominant contrast leakage pattern. Twenty-five of 25 tumors with consensus T1-dominant contrast leakage were low-grade (positive predictive value, 1.0; 95% CI, 0.83-1.00). By comparison, tumors with consensus T2*-dominant contrast leakage or return to baseline were predominantly high-grade (10/15 and 15/23, respectively) with a high negative predictive value (1.0; 95% CI, 0.83-1.0). For pilomyxoid or pilocytic astrocytomas, a T1-dominant leak demonstrated high sensitivity (0.91; 95% CI, 0.70-0.98) and specificity (0.90, 95% CI, 0.75-0.97). CONCLUSIONS: There was good interobserver agreement in the classification of DSC perfusion tissue signal-intensity time curves for pediatric brain tumors, particularly for T1-dominant leakage. Among patients with pediatric brain tumors, a T1-dominant leakage pattern is highly specific for a low-grade tumor and demonstrates high sensitivity and specificity for pilocytic or pilomyxoid astrocytomas.

Diffusion imaging for tumor grading of supratentorial brain tumors in the first year of life.

BACKGROUND AND PURPOSE: Supratentorial tumors in the first year of life are typically large and heterogeneous at presentation, making differentiation of these CNS neoplasms on pre-operative imaging difficult. We hypothesize that the ADC value can reliably differentiate high- versus low-grade supratentorial tumors in this patient population. MATERIALS AND METHODS: A blinded review of ADC maps was performed on 19 patients with histologically proved supratentorial brain tumors diagnosed within the first year of life. Minimum ADC values obtained by region of interest from 2 neuroradiologists were averaged and compared with World Health Organization tumor grade. ADC values for the entire tumor were also obtained by use of a semi-automated histogram method and compared with World Health Organization tumor grade. Data were analyzed by use of Spearman ρ and Student t test, with a value of P < .05 considered statistically significant. RESULTS: For the manual ADC values, a significant negative correlation was found between the mean minimum ADC and tumor grade (P = .0016). A significant difference was found between the mean minimum ADC of the low-grade (1.14 × 10(-3) mm(2)/s ± 0.30) and high-grade tumors (0.64 × 10(-3) mm(2)/s ± 0.28) (P = .0018). Likewise, the semi-automated method demonstrated a significant negative correlation between the lowest 5th (P = .0002) and 10th (P = .0009) percentile individual tumor ADC values and tumor grade, a significant difference between the mean 5th and 10th percentile ADC values of the low-grade and high-grade groups (P = .0028), and a significant positive correlation with values obtained by manual region-of-interest placement (P < .000001). CONCLUSIONS: ADC maps can differentiate high- versus low-grade neoplasms for supratentorial tumors presenting in the first year of life, given the significant negative correlation between ADC values and tumor grade.

Ultrasound-guided fine-needle aspiration biopsy of clinically suspicious thyroid nodules with an automatic aspirator: a novel technique.

BACKGROUND: Fine-needle aspiration biopsy (FNAB) is a simple technique for the investigation of suspicious thyroid nodules. However, low success rates are reported in the literature. The aim of this prospective study was to compare the clinical performance and impact of an automatic aspirator, referred to here as Aspirator 3, to those of the manual technique for the FNAB of clinically suspicious thyroid nodules. METHODS: One hundred nine consecutive patients with 121 clinically suspicious thyroid nodules underwent a biopsy twice of the same site with the clinically approved Aspirator 3 and with the manual technique. The number of follicular cell formations and the total number of follicular cells in the aspirate were counted using the ThinPrep® method. RESULTS: With the Aspirator 3, the total number and the mean number of extracted cell formations were significantly higher than the values achieved with the manual technique (total: 3222 vs. 1951, p=0.02; mean: 27 vs. 16). The total number of cells that were biopsied was also higher when the Aspirator 3 was utilized (47,480 vs. 23,080, p=0.005). Overall, the Aspirator 3 was superior in 65 biopsies, and the manual technique was superior in 39 biopsies. CONCLUSIONS: In terms of cell formations and the total number of cells aspirated, the Aspirator 3 was superior to the manual technique. Further, the Aspirator 3 was more convenient to use and had a greater precision in needle guidance.

A prevalence estimate of pervasive developmental disorder among immigrants to Israel and Israeli natives- a file review study.

BACKGROUND: The prevalence rates of pervasive developmental disorder (PDD) have risen in the West over the last 10 years. There is argument over the etiology of this change in rates. Social and cultural processes including migration have been hypothesized. Israel, as a country of ongoing immigration with a national registry of children diagnosed with PDD, offers an opportunity to compare rates of PDD among immigrants from developing countries and native Israelis. METHOD: A Social Security national registry of 1004 children diagnosed with PDD was reviewed and rates were calculated using data extracted from the Israel National Bureau of Statistics. Of all Jewish children that were born in the years 1983-1997 and who are currently living in Israel, we defined four groups: (1). native Israelis of non-Ethiopian extraction (N = 1198, 300), (2). native Israelis of Ethiopian extraction (N = 15600), (3). immigrants of non-Ethiopian extraction (N = 110300) and (4). children born in Ethiopia (N = 11800). A further breakdown of groups 1 and 3 by well-characterized ethnic or geographical origins was not possible. RESULTS: The rate of PDD was significantly elevated in native Israelis as compared to all immigrant children. Among immigrants, the rate of PDD in Ethiopian-born children was lower than that of those born in other countries. The rate of PDD in immigrant Ethiopian children was much lower than in native Israeli children of Ethiopian extraction. CONCLUSIONS: Birth in Israel, an industrialized country, is a marker for an environmental risk factor for PDD. This may indicate that gestation, birth or infancy in industrialized countries exposes children to environmental insults that increase the risk for contracting PDD.

Sphingosine-1-phosphate effects on PKC isoform expression in human osteoblastic cells.

Sphingosine-1-phosphate (S1P) has been shown to participate in the proliferative process in human osteoblasts.(1) The mitogenic effect of S1P has been postulated to involve two signaling pathways, the Gi linked protein receptor pathway and the PKC pathway. To define the possible role of PKC isoforms in osteoblastic cell proliferation, the effects of S1P on PKC isoform expression was determined. While PKC lambda was minimally detected, the isoforms alpha, delta and iota were all found to be highly expressed by the human osteoblast. In human osteoblastic cells, S1P induced a 25% increase in the expression of PKC alpha and approximately a 30% increase in the expression of PKC iota. S1P did not have an effect on PKC delta expression. Pretreatment with pertussis toxin (PT) led to an inhibition of the observed S1P effects on the expression of the alpha and iota isoforms.

Proliferative and apoptotic responses in cancers with special reference to oral cancer.

The study of signal transduction pathways for mechanisms of apoptosis and proliferation has significantly advanced our understanding of human cancer, subsequently leading to more effective treatments. Discoveries of growth factors and oncogenes, especially those that function through phosphorylation on tyrosine residues, have greatly benefited our appreciation of the biology of cancer. The regulation of proliferation and apoptosis through phosphorylation via tyrosine kinases and phosphatases is discussed, as well as the contributions of other systems, such as serine and threonine kinases and phosphatases. Receptors with seven-transmembrane domains, steroid hormones, genes, and "death domains" will also be discussed. This review attempts to compare the regulation of the growth of normal tissues and cancers with an effort to highlight the current knowledge of these factors in the growth regulation of oral/oropharyngeal cancers. Despite the strides made in our understanding of growth regulation in human cancers, the study of oral/oropharyngeal cancer specifically lags behind. More research must be done to further our understanding of oral cancer biology, if we are to develop better, more effective treatment protocols.

Sphingolipids stimulate cell growth via MAP kinase activation in osteoblastic cells.

Ceramide, ceramide-1-phosphate (C1P) sphingosine (SPH) and sphingosine-1-phosphate (S1P) effects on proliferation and extracellular-signal regulated kinases, ERKs (also known as MAPKs), activation were investigated in human and rat osteoblastic cells. MAPK activation was sphingolipid-specific in cells from both species. In human osteoblastic cells, S1P and C1P markedly stimulated ERK2 phosphorylation with a slight increase in phosphorylation of ERK1. SPH nor ceramide induced phosphorylation of either ERK isoform. In rat osteoblastic cells, SIP, ceramide and SPH stimulated phosphorylation of both isoforms. C1P did not induce phosphorylation of ERK1 but produced a mild increase in phosphorylation of ERK2. In human cells, only S1P significantly (P<0.05) increased osteoblastic cell proliferation, while in the rat cells all four sphingolipids significantly (P<0.05) induced proliferation. The calcium channel blocker verapamil blocked (P<0.05) these effects in both cell types. The MAPK inhibitor, PD98059, inhibited (P<0.05) the mitogenic effect of SIP in human cells. In rat cells, PD98059 effects were less substantial but significant for S1P and C1P. This study demonstrates that sphingolipids are mitogens for both human and rat osteoblastic cells with the MAPK pathway and calcium mediating in part these effects in a species specific manner.

Epidermal growth factor downregulates the expression of SH-PTP2.

Protein phosphorylation/dephosphorylation on tyrosine residues are regulated by tyrosine kinases/phosphatases. The tyrosine phosphatase SH-PTP2 (PTP1D, PTP2C) interacts physically through its SH2 domain with phosphorylated epidermal growth factor receptor (EGFR). In KB cells, an oral epidermoid carcinoma, high epidermal growth factor (EGF) concentrations (10-9, 10-8 and 10-7 M) downregulate its receptor for the duration of the incubation with EGF. Thus, it was hypothesized that in KB cells, SH-PTP2 expression would also be downregulated by high EGF concentrations. This hypothesis was investigated by incubating the KB cells with increasing concentrations of EGF (0, 10-11, 10-10, 10-9, 10-8, 10-7 M) and by evaluating the expression of SH-PTP2 protein under these conditions. This study showed that EGF 10-7 and 10-8 M significantly decreased SH-PTP2 protein expression compared to controls. EGF 10-10 and 10-11 M did not change the expression of SH-PTP2 protein. We conclude that high EGF concentrations downregulate the expression of SH-PTP2 protein.

Differential effect of ethanol on PC12 cell death.

Our goal was to examine the effects of ethanol on cell death using rat pheochromocytoma (PC12) cells as a neuronal model. Withdrawal of serum for 24 hr increased the number of PC12 cells labeled with ethidium homodimer indicating an increase in cell death. Inclusion of 50 mM ethanol during the serum deprivation further increased the amount of ethidium fluorescence by 39%. Although reducing the serum concentration from the usual 15 to 4% did not alter cellular viability, a significant increase in the amount of ethidium fluorescence was observed in PC12 cells incubated for 24 hr in the presence of 4% serum and 150 mM ethanol. No change in viability was observed in cells exposed to either 150 mM ethanol in the presence of 15% serum or 50 mM ethanol in the presence of 4% serum. Inclusion of ethanol during serum deprivation increased the amount of soluble DNA found in the 15,000 x g supernatant. Similarly, using the terminal deoxynucleotidyl transferase dUTP nick-end labeling method to visualize DNA fragmentation in situ, ethanol caused a 213% increase in the number of PC12 cells labeled during serum withdrawal. Agarose gel electrophoresis of the DNA isolated from cells maintained in the absence of serum yielded the classical DNA laddering pattern of 180 to 200 bp fragments suggestive of apoptosis. Ethanol caused a concentration-dependent increase in the amount of DNA laddering in cells deprived of serum. Furthermore, ethanol significantly potentiated the DNA laddering of cells maintained in 4% serum. In contrast to the ethanol-induced increase in cell death when serum factors were reduced or withdrawn, 150 mM ethanol lowered by 34% the number of ethidium-labeled PC12 cells observed after a 30-min exposure to 2 mM H2O2. Similarly, agarose gel electrophoresis of the DNA from H2O2-treated cells did not display DNA laddering. This study demonstrates that: 1) ethanol antagonizes the trophic action of serum factors; 2) pharmacologically relevant ethanol concentrations significantly potentiate apoptosis after serum withdrawal and 3) this enhancement appears specific for apoptosis.

Examiner expectancy effects in the measurement of pressure pain thresholds.

The ascending Method of Limits, used for the determination of pressure pain thresholds (PPT), is not a psychophysically robust method. The present study sought to determine if the examiner's expectancy, based on whether the measurement site was clinically 'painful' or 'non-painful', would bias the obtained PPT values. Twenty-eight patients with facial or temporal area pain served as subjects, and in each subject, a pain site and a control site were identified and marked. According to a randomization schedule, the pain and control sites were correctly marked in half of the subjects and were mis-labeled in the other half, thereby controlling the examiner's knowledge of a site and thus the examiner's expectancy of what the PPT should be. Two examiners, shown to be reliable with each other in both pre-clinical and post-clinical reliability studies, were blind to the true purpose of the study and to the marking procedures. Each examiner made one PPT measurement at each marked site in a counterbalanced measurement order. Manipulating the examiner's prior knowledge of the measurement site's characteristics significantly lowered the obtained PPT values for control sites but did not significantly alter the PPT at the clinically painful sites. Nevertheless, the pain sites still had significantly lower PPTs than did control sites. We conclude that: (i) PPTs at pain sites are robust to a major source of measurement bias associated with the ascending Method of Limits; (ii) measurement order and knowledge of measurement site characteristics can influence obtained PPT; and (iii) the common protocol in which the examiner monitors the amount of pressure during PPT measurement in order to control the force application rate may serve as a mechanism that can bias the obtained values.

Alterations in receptor-mediated kinases and phosphatases during carcinogenesis.

Increased phosphorylation in cancers can stimulate growth and up-regulate certain receptors. To test whether the functional response of phosphatase receptors is up-regulated during carcinogenesis, we examined the effects of ligands on net phosphorylation in isolated membranes derived from hamster cheek-pouch tissues undergoing malignant transformation. The buccal mucosa of groups of Syrian golden hamsters was exposed thrice weekly to 0.5% dimethylbenzanthracene (DMBA) in acetone for 2-12 weeks to produce premalignant and malignant tissues. Homogenates of these tissues were then incubated with [32P]ATP in the presence of epidermal growth factor (EGF), agonist of somatostatin analogue RC-160, luteinizing-hormone-releasing hormone (LH-RH) [D-Trp6]LH-RH, or combinations of EGF, RC-160, and [D-Trp6]LH-RH. Changes compared to controls in phosphorylation in response to ligands provided estimates of kinase or phosphatase activity. Phosphorylation increased continuously, from the first application of DMBA in a linear fashion, and independently of EGF stimulation. RC-160 and [D-Trp6]LH-RH reduced phosphorylation in vitro. This response occurred in premalignant (weeks 6-10 after DMBA application) as well as malignant tissues (week 12 after DMBA application), but was not significant in normal tissues. The results show a continuous augmentation in phosphatase activity prior to the appearance of cancers, but with a delay in expression following the primary event of increased kinase activity. Significantly less phosphorylation of substrates was induced by both RC-160 and [D-Trp6]LH-RH after in vitro activation by EGF than in the absence of EGF. This suggests that EGF activates latent systems of hormonal receptors. Collectively, these results support the hypothesis that the enhancement of the hormonally stimulated phosphatase in cancers occurs secondarily to the increased kinase activity.

Synergistic effects of bombesin and epidermal growth factor on cancers.

Bombesin and gastrin-releasing peptide act as autocrine mitogens in various cancers. Bombesin antagonist RC-3095 inhibited growth in some cancers and slowed the progression of premalignant lesions, possibly by down-regulating epidermal growth factor (EGF) receptors. Since the EGF receptor mitogen response involves tyrosine kinase stimulation, we tested the hypotheses that bombesin stimulates, and RC-3095 inhibits, phosphorylation; EGF and bombesin promote the phosphorylation of the same substrates; and EGF and bombesin act synergistically on phosphorylation. Therefore, in vitro assays for phosphorylation were performed in the presence or absence of EGF, bombesin, RC-3095, and combinations in samples derived from tumor, tissue surrounding tumor, cell lines, and normal and transforming tissue derived from the 9,10-dimethyl-1,2-benzanthracene-induced squamous cell lesions of the hamster cheek pouch. Bombesin increased, and RC-3095 decreased, phosphorylation in these samples. In the human hepatoma sample and surrounding tissue, these ligands altered the phosphorylation of the same substrates affected by EGF. EGF and bombesin stimulated phosphorylation synergistically in the hamster samples and the hepatoma. Bombesin-induced phosphorylation was greater in tissue surrounding the hepatoma, whereas RC-3095 was more effective in inhibiting phosphorylation in the hepatoma itself. This cancer, therefore, could be endogenously stimulated by gastrin-releasing peptide. These observations support the hypothesis that bombesin stimulates growth of tissues and tumors by amplifying the phosphorylation response to EGF. The growth inhibitory response to RC-3095, or other bombesin analogues, of individual tumors may be prognosed by in vitro phosphorylation assays using the samples from the patient's tumor.

Effects of epidermal growth factor and analogues of luteinizing hormone-releasing hormone and somatostatin on phosphorylation and dephosphorylation of tyrosine residues of specific protein substrates in various tumors.

Analogues of somatostatin (SS) and luteinizing hormone-releasing hormone (LH-RH) activate tyrosine phosphatases in MIA PaCa-2 human pancreatic cancer cell line membranes and inhibit growth. We compared the substrates phosphorylated by epidermal growth factor (EGF) to those dephosphorylated by the SS analogue RC-160 (D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2) and [D-Trp6]LH-RH in cancer cell lines such as MIA PaCa-2 (human pancreatic cancer), HCPC (hamster cheek pouch carcinoma), A-549 (human lung cancer), HT-29 (human colon cancer), and R3230AC (breast cancer). EGF phosphorylated proteins of 170, 65, and 60 kDa and analogues of SS and LH-RH promoted the dephosphorylation of these proteins in MIA PaCa-2 and HCPC cell lines. The EGF receptor is 170 kDa. pp60src (60 kDa) is known to be a substrate for EGF receptor. The LH-RH receptor is also 60 kDa. The effects of RC-160 and [D-Trp6]LH-RH were quantitatively different. Examinations of HT-29, A-549, and R3230AC cancer cell lines revealed no phosphorylation by EGF or dephosphorylation by RC-160 and [D-Trp6]LH-RH. In addition to the 170-, 65-, and 60-kDa proteins, 35-kDa proteins were also phosphorylated in some cancer cell lines. This work demonstrates that analogues of SS and LH-RH can reverse the effects of EGF biochemically as well as functionally.

Regulation of luteinizing hormone-releasing hormone receptor binding by heterologous and autologous receptor-stimulated tyrosine phosphorylation.

Pancreatic cancers overexpress tyrosine kinase and luteinizing hormone-releasing hormone (LH-RH) receptor (LH-RHR)-mediated tyrosine phosphatase. LH-RHR is a 60-kDa protein. One of the substrates of epidermal growth factor (EGF)-stimulated tyrosine kinase activity and LH-RH- and somatostatin-stimulated tyrosine phosphatase activity is also a 60-kDa protein. This suggests the possibility that LH-RHR regulation by tyrosine phosphatase and tyrosine kinase is mediated by (de)phosphorylation of existing LH-RHR. To test this hypothesis, membranes of MIA PaCa-2 cells, a human dedifferentiated pancreatic cancer cell line, were incubated without hormone (control) or with 0.1 microM EGF or somatostatin analogue RC-160 for 1 hr at 4 degrees C to phosphorylate the 60-kDa protein. Competition binding experiments with I125-labeled [D-Trp6]LH-RH by displacement with a nonradioactive ligand showed that the LH-RH binding in 69% of the points was increased by EGF and 85% was decreased by RC-160 compared with controls (n = 61; both significant, P less than 0.001). The specific binding was altered, increasing 50-150% after preincubation with EGF and decreasing 60-70% after RC-160. No change was seen in the binding affinity constant after pretreatment with EGF or RC-160. This shows that phosphorylation regulates binding of LH-RH and may explain the up-regulation by EGF and down-regulation by RC-160 and by LH-RH of the LH-RH response.