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OBJECTIVE: This study describes the predictive value of oral epithelial dysplasia (OED) grading as an indicator for malignant transformation and progression. STUDY DESIGN: The records of an Australian-based pathology laboratory were searched for oral mucosal biopsies with a dysplastic or malignant diagnosis. Examination for an association with progression and malignant transformation without reinterpretation was performed. Analysis was undertaken using hazard ratios and the Fisher exact test. RESULTS: A total of 368 patients with a diagnosis of OED were included. Twenty-six patients (7.1%) underwent progression or malignant transformation; the annual malignant transformation rate was 1%. No other characteristics were associated with a heightened risk of progression or transformation. CONCLUSIONS: The severity of OED was not associated with risk of malignant transformation, suggesting that the current OED grading system is not useful for predicting patient outcomes or for determining management strategies. Definitive treatment of all OED is recommended, until a more reliable progression/transformation system is developed.

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In several rodent species, an increase or recovery of sexual behavior can be observed when sexually satiated males are placed in contact with a novel mate. In order to assess the influence of female novelty on the courtship behavior of guinea pigs (Cavia porcellus), four adult males were observed during four daily 15-min sessions while interacting with the same pregnant female (same-female sessions). A new female was presented during the fifth session (switched-female session). The duration of behavioral categories was obtained from videotape records using an observational software. From the first to the second session, all males decreased the time allocated to investigating (sniffing and licking), following, and mounting the female, and that response did not recover by the end of the same-female sessions. No similar decreasing tendencies were detected in the circling or rumba categories. A marked increase of investigating occurred in all males from the last same-female session (8.1, 11.9, 15.1 and 17.3 percent session time) to the switched-female one (16.4, 18.4, 37.1 and 28.9 percent session time, respectively). Increases in following and circling were recorded in three of four males, and full-blown recovery of mounting in one male. No consistent changes in the females' responses to males (following or attacking) were observed throughout testing. These results are consistent with the hypothesis that guinea pig males recognize individual females and that courtship responses may suffer a habituation/recovery process controlled by mate novelty.

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In several rodent species, an increase or recovery of sexual behavior can be observed when sexually satiated males are placed in contact with a novel mate. In order to assess the influence of female novelty on the courtship behavior of guinea pigs (Cavia porcellus), four adult males were observed during four daily 15-min sessions while interacting with the same pregnant female (same-female sessions). A new female was presented during the fifth session (switched-female session). The duration of behavioral categories was obtained from videotape records using an observational software. From the first to the second session, all males decreased the time allocated to investigating (sniffing and licking), following, and mounting the female, and that response did not recover by the end of the same-female sessions. No similar decreasing tendencies were detected in the circling or rumba categories. A marked increase of investigating occurred in all males from the last same-female session (8.1, 11.9, 15.1 and 17.3 percent session time) to the switched-female one (16.4, 18.4, 37.1 and 28.9 percent session time, respectively). Increases in following and circling were recorded in three of four males, and full-blown recovery of mounting in one male. No consistent changes in the females' responses to males (following or attacking) were observed throughout testing. These results are consistent with the hypothesis that guinea pig males recognize individual females and that courtship responses may suffer a habituation/recovery process controlled by mate novelty.

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The tests that are currently available for the measurement of overexpression of the human epidermal growth factor-2 (HER2) in breast cancer have shown considerable problems in accuracy and interlaboratory reproducibility. Although these problems are partly alleviated by the use of validated, standardised 'kits', there may be considerable cost involved in their use. Prior to testing it may therefore be an advantage to be able to predict from basic pathology data whether a cancer is likely to overexpress HER2. In this study, we have correlated pathology features of cancers with the frequency of HER2 overexpression assessed by immunohistochemistry (IHC) using HercepTest (Dako). In addition, fluorescence in situ hybridisation (FISH) has been used to re-test the equivocal cancers and interobserver variation in assessing HER2 overexpression has been examined by a slide circulation scheme. Of the 1536 cancers, 1144 (74.5%) did not overexpress HER2. Unequivocal overexpression (3+ by IHC) was seen in 186 cancers (12%) and an equivocal result (2+ by IHC ) was seen in 206 cancers (13%). Of the 156 IHC 3+ cancers for which complete data was available, 149 (95.5%) were ductal NST and 152 (97%) were histological grade 2 or 3. Only 1 of 124 infiltrating lobular carcinomas (0.8%) showed HER2 overexpression. None of the 49 'special types' of carcinoma showed HER2 overexpression. Re-testing by FISH of a proportion of the IHC 2+ cancers showed that only 25 (23%) of those assessable exhibited HER2 gene amplification, but 46 of the 47 IHC 3+ cancers (98%) were confirmed as showing gene amplification. Circulating slides for the assessment of HER2 score showed a moderate level of agreement between pathologists (kappa 0.4). As a result of this study we would advocate consideration of a triage approach to HER2 testing. Infiltrating lobular and special types of carcinoma may not need to be routinely tested at presentation nor may grade 1 NST carcinomas in which only 1.4% have been shown to overexpress HER2. Testing of these carcinomas may be performed when HER2 status is required to assist in therapeutic or other clinical/prognostic decision-making. The highest yield of HER2 overexpressing carcinomas is seen in the grade 3 NST subgroup in which 24% are positive by IHC.

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A total of 179 cases of lymphoma, both nodal and extranodal, recorded in the Papua New Guinea Tumor Registry were reviewed and classified by the updated Kiel classification. Fifteen (8.4%) were Hodgkin's disease, 39 (21.8%) probable Burkitt's lymphoma (poorly preserved), 46 (25.7%) Burkitt's lymphoma, 33 (18.4%) Burkitt's-like lymphoma, 36 (20.1%) other B-cell subtypes and 10 (5.6%) T-cell lymphoma. No case of follicular B-cell lymphoma was encountered.

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Primary renal osteogenic sarcoma is a rare tumour which requires differentiation from osteoid formation in sarcomatoid variants of renal cell carcinoma. The diagnosis in this case was suggested pre-operatively by marked elevation of serum alkaline phosphatase in the absence of bone disease. The poor prognosis is emphasized.

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Collagenase digestion allows cells to be released into suspension from bone marrow tissue. Discrete abnormal populations of lymphoid cells can be identified by cell morphology and immunological phenotyping techniques. Viable cells are also available for chromosomal analysis. This technique makes cells available for analysis in cases of dry bone marrow taps and has a particular use in the investigation of bone marrow involvement by malignant lymphoma.

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A field experiment was conducted with preschool children to test the effect of rewards on a familiar, spontaneous play activity, in conditions as close as possible to the children's natural school context, and to examine the role of familiarity of the person who administered rewards. In three experimental conditions, children were rewarded either by their own teacher or by an unknown adult for playing with toys at the school playground and stayed with either the teacher or the unknown adult in the remaining part of reward sessions. Spontaneous play was significantly reduced by the reward relative to baseline levels and recovered after a 3-wk. interval. However, no difference due to familiarity/unfamiliarity of reward agent could be found. Results, discussed in terms of an incentive contrast hypothesis, attest to the generality and external validity of the undermining effects of rewards.

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A technique for the extraction of cells from bone marrow trephine core biopsy specimens using collagenase digestion was assessed in 39 cases (33 diagnostic and six normal). Diagnostically useful numbers of cells were extracted from all marrows. Morphological assessment of cytocentrifuge preparations of these cells gave a correct diagnosis in 23 (60%) of cases compared with 27 (70%) for the corresponding aspirated marrow smears. Phenotypic analysis using flow cytometry showed persistence of a range of surface membrane antigens following collagenase digestion. Increased autofluorescence was a problem in some cases. Cytochemistry, bone marrow culture, and cytogenetic analysis could also be carried out on these cells. It is concluded that this technique has useful diagnostic applications in cases of dry taps.

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Fatal spontaneous rupture of the liver is described in a 46-year-old women with hepatic amyloidosis diagnosed premortem by liver biopsy. An autopsy revealed systemic amyloidosis, with no evidence of an underlying chronic inflammatory condition, infection, or immunocyte dyscrasia. By computerized search, this is only the third reported case of spontaneous rupture of the liver complicating amyloidosis.

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To test Bindra and Palfai's hypothesis about enhancing and inhibitory motivational effects of a conditioned stimulus on exploratory behavior, rats in a first experiment were submitted to pairings of a tone with (a) water, (b) intermittent deliveries of water after a period of constant pairing. In a control condition, the tone was presented alone. The tone was subsequently presented during oriented exploration of a novel stimulus, in the conditioning context. There was no difference in exploratory performance between conditions. In a second experiment with another kind of stimulus change and a larger number of training trials, exploration did not increase when occurring during CS presentation. The lack of facilitation which is possibly the product of competition between exploration and magazine-directed responses, can also be interpreted as indicating that the effects of a conditioned stimulus are reinforcer specific and that the diffuse activity it generates in a situation different from the training one is not equivalent, as concerns the processes involved, to oriented exploratory behavior.

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Novel stimuli were presented in a runway where rats run for food. Subjects in a pre-exposure condition (n = 6) were exposed to visual and auditory stimulation and then to an olfactory stimulus; subjects not preexposed (n = 6) only received the olfactory stimulus. Reaction to the odor was lower in pre-exposed subjects. This result suggests cross-modal generalization effects in at least one kind of habituation of the rat.

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