Skipping breakfast: morningness-eveningness preference is differentially related to state and trait food cravings.

Eveningness preference is associated with unhealthy eating behaviors. We measured state and trait food cravings in chronotypes in the morning and in the evening. Less Evening (E)- than Morning (M)-types reported to have had breakfast. Accordingly, hours that had elapsed since the last meal were higher in E- than M-types in the morning, but did not differ between groups in the evening. E-types reported higher anticipation of positive reinforcement that may result from eating than M-types in the morning, but both had the same hunger levels. On a trait level, M-types reported more feelings of guilt for giving into cravings compared to E-types. Results suggest that E-types skip breakfast more often than M-types, but this eating pattern does not inevitably lead to more food cravings in the evening or more pronounced habitual cravings. Furthermore, E-types did not experience more hunger in the morning although they had not been eating for a longer time period. Results support findings about a different lifestyle in E-types compared to M-types.

[Salivary duct carcinoma]. / Speichelgangkarzinome.

This tutorial focuses on salivary duct carcinoma (SDC), a rare, high grade neoplasm mainly of major salivary glands. The clinical course of these tumors is characterised by extended local disease, early distant metastasis, and poor outcome. The morphology of SDC is reminiscent of breast ductal carcinomas and may occasionally cause diagnostic problems. In spite of mimicry with ductal carcinoma in situ of the breast and an in situ component, that is evident in most tumors by immunohistology with antibodies directed against high molecular weight cytokeratins (Ck), SDC is always an invasive carcinoma. By immunohistology, most tumors show reactivity with antibodies directed against Ck 7, Ck 8/18 and Ck 19 whereas a morphologically indistinguishable subgroup expresses Ck 5/6 in tumor cells in addition to residual basal epithelia. Carcinoembryonic antigen, GCDFP-15 and androgen receptor are other helpful markers in routine diagnosis of SDC. Prostate-specific antigen is detectable in some cases. Abnormal p53 expression seems to indicate an adverse prognosis. Expression of c-erbB2, the over-expression of which is associated with a poor prognosis, may form the basis for a targeted therapeutic approach for selected cases of SDC.

[Myoepthelial tumors of salivary glands]. / Myoepitheliale Tumoren der Kopfspeicheldrüsen.

This tutorial focuses on myoepithelial tumors of salivary glands, an entity with heterogeneous cytomorphology and inconsistent immunophenotype. Moreover, the clinical course cannot be predicted reliably from cytomorphological and immunophenotypic analysis. This heterogeneity causes problems in routine diagnostic, so that diagnosis ultimately rests on conventional histology. In a representative series of myoepitheliomas and malignant myoepitheliomas, antibodies against cytokeratins 5/6, S 100 protein and vimentin produced the most consistent reactivity profile. Staining for cytokeratins 5/6 is a useful addition to the established immunohistologic marker panel in the work-up of myoepitheliomas, because of its reliable expression in most cases and because it may underline the epithelial nature of the lesion. Comparative genomic hybridisation (CGH) profiles of myoepitheliomas and myoepithelial carcinomas showed no chromosomal aberration in less than 50% of myoepithelial carcinomas, so that CGH is of limited help in a given case. In a case that was represented in three separately localized manifestations of the disease that differed in their CGH profiles, gross genetic aberrations suggest to be acquired during tumor progression and should raise the suspicion of malignancy. Thus, diagnosis of myoepithelial tumors of salivary glands has to rest on morphological grounds with support of a restricted panel of immunohistologic markers.

Restorative impact of rabeprazole on gastric mucus and mucin production impairment during naproxen administration: its potential clinical significance.

Rabeprazole augments gastric mucus and mucin production in humans. However, its potential restorative impact on gastric mucus and mucin production impairment, resulting from administration of naproxen, remained to be explored. Therefore, we measured the content of mucus and mucin in gastric juice (GJ) before and after administration of naproxen with rabeprazole or placebo. The study was approved by HSC at KUMC and conducted in 21 asymptomatic, H. pylori-negative volunteers in a double-blind, placebo-controlled, crossover design. The content of gastric mucus in GJ, after exhaustive dialysis and complete lyophilization, was assessed gravimetrically, whereas the content of mucin was measured after its purification with equilibrium density-gradient ultracentrifugation in CsC1. Gastric mucus secretion during administration of naproxen with placebo declined significantly both in basal (by 44%; P < 0.001) and in pentagastrin-stimulated (by 35%; P < 0.001) conditions. Coadministration of rabeprazole significantly restored the naproxen-induced impairment in mucus production in basal conditions (by 47%; P < 0.01) and by 22% during stimulation with pentagastrin. Gastric mucin secretion during naproxen/placebo administration also declined significantly in both basal (by 39%; P < 0.01) and stimulated (by 49%; P = 0.003) conditions. Rabeprazole also significantly restored the naproxen-induced decline of gastric mucin output during pentagastrin-stimulated conditions (by 67%; P = 0.003) and by 40% in basal conditions (P = 0.05). The restorative capacity of rabeprazole on the quantitative impairment of gastric mucus and mucin during administration of naproxen may translate into a clinical benefit of protection of the upper alimentary tract from NSAID-related mucosal injury.

[Sodium selenite reduces acute radiogenic damage of the rat parotid glands during fractionated irradiation]. / Reduktion akuter radiogener Schädigungen durch Natriumselenit. Wirksamkeit unter fraktionierter Bestrahlung der Glandula parotis der Ratte.

BACKGROUND: In vitro studies show that sodium selenite is a potential radioprotector in normal cell cultures, but not tumor cells. The aim of this study was to evaluate the cytoprotective potency of sodium selenite during conventional fractionated irradiation of rat salivary glands, but also on tumor response and metastasis frequency of rhabdomyosarcomas R1H. METHOD: The head-neck area of male WAG/RijH rats and the tumor in the flank were irradiated with (60)Co-gamma-rays (60 Gy/30 fractions/6 weeks). Sodium selenite (15 microg/kg body weight) was applied through a venous port 30 min before irradiation. Rats of a control group were treated in the same manner with an equal volume of physiologic sodium chloride. In the course of treatment the salivary glands were extirpated at different stages and examined histopathologically. The evaluation of the gland function was performed prior to and after radiotherapy by sialoscintigraphy. Tumor volume was measured during irradiation and plotted in tumor-volume curves. Rat body weight was determined sequentially to estimate the general constitution of the animal during the treatment. RESULTS: Irradiation caused dose-dependent damage in the salivary glands. Intra- and intercellular edema (16 Gy), vacuolization (30 Gy), degranulation (46 Gy), and necrosis of the acinar cells (60 Gy) occurred. Sodium selenite delayed the development of the described damage, and the amount of necrotic acinar cells after the application of 60 Gy was reduced (control: 75% vs sodium selenite 30%), confirmed by the sialoscintigraphic results. The loss in gland function in the control group was 44% vs 74% (p<0.05) in the sodium selenite group. Sodium selenite had no influence on the response of R1H tumors to radiation and general constitution. CONCLUSIONS: Based on morphological and sialoscintigraphic findings, a cytoprotective effect on acute toxicity of rat salivary glands could be detected under irradiation with synchronous application of sodium selenite. In addition, no effects on tumor response and metastasis frequency were observed. The general animal constitution was not affected by additional medication with sodium selenite during irradiation.

[Histomorphologic and salivary gland scintigraphic findings in radiation-induced sialadenitis due to fractionated irradiation of the head and neck region of rats. A model for evaluating potentially radioprotective substances]. / Histomorphologische und sialoszintigraphische Befunde zur Radiosialadenitis unter fraktionierter Bestrahlung der Kopf-Hals-Region von Ratten. Ein Modell zur Evaluierung potenziell radioprotektiver Substanzen.

INTRODUCTION: The aim of this study was to correlate structural, histomorphological damage of the salivary gland with scintigraphic findings during fractioned radiotherapy. METHODS: The head and neck area of 27 WAG/RijH rats was irradiated with (60)Co-gamma-rays (60 Gy/30f/6 weeks). A port-system was implanted and (99m)Tc-pertechnetat applied at different stages of irradiation (0, 16, 30, 46, 60 Gy and 6 months post irradiation). RESULTS: After the application of 16 Gy an intra- and extra-cellular oedema developed in the salivary glands. The progressive vacuolisation (30 Gy) passed over into lipomatosis (46 Gy) and necrosis (60 Gy) in the parotid and mandibular glands. Six months after irradiation treatment, the chronic histomorphological damage corresponded to stage II according to Seifert. The corresponding loss in gland function was 13% (16 Gy); 26% (30 Gy); 57% (46 Gy); 75% (60 Gy) and 66.5% (6 months post irradiation). CONCLUSION: This animal model demonstrates the correlation between histomorphological and scintigraphic findings.

[Reducing late toxicity with amifostine in fractionated irradiation of the rat salivary glands]. / Reduktion der Spättoxizität durch Amifostin bei fraktionierter Bestrahlung der Rattenspeicheldrüsen.

Clinical studies show that amifostine can reduce xerostomia and mucositis during radiotherapy of head and neck cancers. The aim of this study was to evaluate the radioprotective potency of amifostine with respect to late toxicity of salivary glands of rats. The head-neck-area of 8 male WAG/RijH rats (295 +/- 7 g) were irradiated with 60Co-gamma-rays (60 Gy/30 f/6 weeks). Amifostine (250 mg/m2 body surface) was applied via a venous port 15 min before each irradiation. Rats of a control group were irradiated with the same schedule with equal volumes of physiological saline. The morphological and sialoscintigraphical findings clearly demonstrate that amifostine has a remarkable cytoprotective effect on the late toxicity of irradiated salivary glands.

[Radioprotective effectiveness of amifostine on the salivary glands of the rat during fractionated irradiation]. / Radioprotektive Wirksamkeit von Amifostin auf die Speicheldrüsen der Ratte unter fraktionierter Bestrahlung.

BACKGROUND: The aim of this study was to evaluate the cytoprotective potency of amifostine during a fractioned irradiation of salivary glands but also on the tumor response of rhabdomyosarcomas R1H in rats. METHOD: The head-neck-area of male WAG/RijH rats and the tumor in the flank were irradiated with 60Co-gamma-rays (60 Gy/30 f/6 weeks). Amifostine (250 mg/m2) was applicated 15 min before irradiation. The control group was treated with an equal volume of physiologic sodium chloride. The salivary glands were exstirpated and examined histopathologically. Tumour volume was measured, the body-weight of rats determined. RESULTS: A dose dependent radiosialadenitis developed in all salivary glands. Amifostine had no influence on the response of R1H tumours to radiation. The animal weight loss in the amifostine group was higher as compared to control group. CONCLUSIONS: No cytoprotective effects on acute toxicity of salivary glands of rats could be detected under irradiation with synchronous application of amifostine. In addition, no effects on tumor response were observed. The general animal constitution decreased by additional medication of amifostine.

Role of sugar hydroxyl groups in glycoside hydrolysis. Cleavage mechanism of deoxyglucosides and related substrates by beta-glucosidase A3 from Aspergillus wentii.

The contribution of the hydroxyl groups at C-2 and C-4 and of the hydroxy-methyl group at C-5 of beta-glucopyranosides to their hydrolysis by beta-glucosidase A3 (beta-D-glucoside glucohydrolase, EC 3.2.1.21) from Aspergillus wentii was investigated with 4-methylumbelliferyl-beta-glucosides with appropriate structural modifications. Relative hydrolysis rates expressed by kcat/kcat (glucoside) are: 2-deoxy, 4. 10(-6); 2-deoxy-2-amino, 2.4 . 10(-4); 2-deoxy-2-ammonio, less than 1 . 10(-6); 4-deoxy, 1.8 . 10(-4); xyloside, 6.3 . 10(4); galactoside, less than 1 . 10(-6). Binding to the active site as measured by the Km value of these substrates or by the Ki value of the appropriate inhibitors is only moderately decreased by the above modifications. A temperature study with the 2-deoxyglucoside showed that the decrease in kcat is not due to a change in delta H but to a more negative delta S. The steady-state hydrolysis of the 2-deoxyglucoside is approached with a "burst" (rate constant 0.13 min-1) at pH 6 and 1 mM substrate; deglycosylation of the enzyme is partially rate-limiting. Rate constants for glycosylation and deglycosylation calculated from pre-steady-state kinetics were in good agreement with the constants calculated from experiments where the 2-deoxyglucoside was used as an inhibitor for the hydrolysis of the glucoside and where a slow approach to the steady state of the inhibited reaction is observed.