OS06.7.A Underlying mechanisms of verbal fluency in glioma patients: language or executive functioning?

Background Glioma patients often suffer from cognitive deficits, such as in language and executive functioning (EF). A sensitive test to identify these deficits is verbal fluency (VF). In VF, participants are asked to generate as many unique words within a given semantic category (category fluency - CF) or starting with a given letter (letter fluency - LF) within one minute. While both language and EF play a role in VF, the relative contribution of both domains remains unclear. We aim to retrospectively investigate performance on VF and, for the first time, on Non-Verbal Fluency (NVF), requiring to connect 5 points in different patterns within three minutes. Additionally, we aim to explore the influence of language and EF on VF performance in glioma patients.

Materials and Methods 69 adults with gliomas in eloquent areas underwent a comprehensive neuropsychological test-battery at 1-2 months before surgery (T1) and 3 (T2) and 12 months (T3) after surgery. The protocol consisted of VF (CF: animals, professions, LF: D-A-T/K-O-M), language tests (Repetition (Akense Afasie Test), Token Test, Boston Naming Test) and EF tests (Five Point Test, Trail Making Test, Stroop Colour-Word Test, Wisconsin Modified Card Sorting Task). VF and NVF performance were compared 1) to healthy population using one sample t-tests/Wilcoxon rank-tests (all patients), and 2) between T1, T2, and T3 with paired sample t-tests/Wilcoxon rank-tests (31 patients). Linear regression analyses were conducted to investigate the predictive value of language and EF on VF for all patients.

Results Preoperatively, patients were impaired on all VF tasks. Especially CF profession performance was more prone to deterioration after surgery at T2 and T3. In contrast, NVF was intact and even improved after surgery (T1-T3, T2-T3). NVF (p = .032, EF) was a predictor for CF animals while the Token Test (p = .023, language) was a predictor for CF professions. Both NVF (p = .032, EF) and the Token Test (p = .004, language) were predictors for LF.

Conclusion First, glioma patients were preoperatively impaired in VF but were preserved in NVF, as is in line with the literature. Secondly, CF professions appeared to be particularly sensitive to detect long-term postoperative decline. Thirdly, the main result of this study is that both language and EF mechanisms appeared to be responsible for VF performance in glioma patients. These findings are useful for interpreting VF impairment in glioma patients and for therapeutic interventions, suggesting a combination of language and EF training materials.

Fish and omega-3 fatty acid intake in relation to circulating fibroblast growth factor 23 levels in renal transplant recipients

BACKGROUND AND AIMS

A high circulating fibroblast growth factor 23 (FGF23) level is an independent risk factor for cardiovascular mortality in renal transplant recipients and the general population. N-3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) may contribute to cardiovascular risk reduction. We investigated whether fish and EPA-DHA intake are related to FGF23 levels in renal transplant recipients.

METHODS AND RESULTS

We performed a cross-sectional analysis in 619 stable renal transplant recipients (mean age 53 years, 57% male, estimated glomerular filtration rate [eGFR] 53 ± 20 mL/min/1.73 m(2)). Dietary intake was assessed by a 177-item food frequency questionnaire. Serum intact FGF23 was measured by ELISA. We examined differences in FGF23 levels across categories of fish and EPA-DHA intake using analysis of variance models adjusted for age, sex, dietary and lifestyle factors and key determinants of FGF23. Patients consumed on average 15 g of fish and 139 mg EPA-DHA/day. Median FGF23 was 62 pg/mL (IQR 43-98 pg/mL). Higher dietary EPA-DHA and fish intake were associated with lower serum FGF23 levels. Subgroup analyses revealed that particularly in patients with reduced renal function (eGFR <60 mL/min/1.73 m(2)), adjusted FGF23 levels (114, 79, 75 pg/mL, P = 0.0001) were inversely associated with tertiles of EPA-DHA intake. Similarly, we observed an inverse association between fish consumption and serum FGF23 levels in adjusted analyses.

CONCLUSION

A higher intake of fish and dietary n-3 fatty acids (EPA-DHA) is related to lower circulating FGF23 levels in renal transplant recipients. Further research is needed to assess the causality of this association and the clinical implications.

Schistonchus africanus n. sp. (Aphelenchida: Aphelenchoididae) Associated with Ficus thonningii (Moraceae) and its Pollinator Wasp Elisabethiella stuckenbergi (Chalcidoidea: Agaonidae)

Syconia ("figs") from Ficus thonningii and adults of its pollinator wasp Elisabethiella stuckenbergi were dissected to elucidate their association with a new species of Schistonchus (Aphelenchoididae). Schistonchus africanus n. sp. is characterized by a short stylet (13-16 mum long); position of the excretory pore opening in both sexes at a level just behind the stylet knobs; and short post-uterine branch, one body-width long. Schistonchus africanus n. sp. parasitizes F. thonningii florets and is transported by the winged females of E. stuckenbergi. Juveniles, females, and males of the nematode were found in the female and male fig florets and in the abdomen of the vector. Nematode populations extracted from female wasps or fig floret tissues did not differ in their morphology. No association was observed with the wingless males of the pollinator wasp.

Chromosomal findings and p53-mutation analysis in chromophilic renal-cell carcinomas

The chromosomal pattern of 31 specimens of chromophilic renal-cell cancer (RCC), selected according to the criteria mentioned in the classification of Thoenes and Störkel, is presented. A high male preponderance was found (8.7:1). Cytogenetic analysis revealed a typical pattern of numeric alterations specific for this sub-type in the majority of cases (i.e., --Y,+7, +12, +16, +17, and/or +20), which is different from the chromosomal patterns found in other sub-types of RCC. Gain of chromosome 20, as well as loss of the extra copy of chromosome 17 or loss of 17p, was found to be related to the higher-grade chromophilic carcinomas. None of the 14 cases examined by SSCP analysis revealed mutations of the p53 gene, indicating that other genes at 17(p) might be important in the progression of this sub-type of RCC.

Comparison of cytogenetic abnormalities and deoxyribonucleic acid ploidy of benign, borderline malignant, and different grades of malignant soft tissue tumors

BACKGROUND

Both DNA flow cytometry and cytogenetic analysis have been used to study soft tissue tumors. With flow cytometry, the DNA content of a relatively large number of cells can be examined, but cytogenetic analysis gives more detailed information about genomic changes.

EXPERIMENTAL DESIGN

In order to compare the advantages and drawbacks of DNA flow cytometry versus chromosomal analysis, 92 primary or recurrent malignant, 16 borderline malignant, and 13 benign soft tissue tumors were karyotyped after short-term culture. DNA ploidy was determined by flow cytometry of suspensions prepared from frozen or paraffin-embedded samples. From 97 patients, 121 samples were analyzed.

RESULTS

On the basis of the results, four groups were distinguished: DNA-euploid tumors with normal diploid karyotypes (group a) or with abnormal (group b) karyotypes, and DNA-aneuploid tumors with normal (group c) or abnormal (group d) karyotypes. The findings in group b show that structural chromosomal abnormalities or minor numerical aberrations of chromosomes are not detected by DNA flow cytometry. In group c, the finding of tumors with an aneuploid DNA-profile and cells with normal karyotypes is most likely due to overgrowth of fibroblasts during culture and subsequent karyotyping of normal cells.

CONCLUSIONS

The findings show that a) DNA flow cytometry has a higher success rate than karyotyping, b) both techniques are complementary, such that DNA flow cytometry gives an "overview", whereas karyotyping gives more detailed information; comparison of both techniques in individual cases leads to a better understanding of the chromosomal events that occurred during oncogenesis, c) histologically low grade tumors are generally DNA-diploid, but may have an abnormal karyotype, and d) histologically high-grade sarcomas tend to have an aneuploid DNA-profile; they are generally more difficult to karyotype.

DNA ploidy and karyotype in recurrent and metastatic soft tissue sarcomas

To study mechanisms involved in evolution of soft tissue sarcomas, we compared DNA ploidy and karyotypes at different stages of their disease in two patients with myxoid liposarcomas (MLS), one with a fibrosarcoma (FS), and two with rhabdomyosarcomas (RMS). None of the MLS samples revealed clearcut histologic changes in later samples as compared to their primaries, and the DNA ploidy in all samples was diploid. In one patient karyotypes at four different times during the 19 yr of his disease all revealed a t(11;12) (p15;q13), but additional clonal chromosomal abnormalities occurred only in later recurrences. In another patient the karyotypes obtained in the 26th and 28th yr of his disease were similar and included the t(12;16) (q13;p11), characteristic of MLS. A comparison with karyotypes of six other MLS patients at different disease stages suggests that the presence of a t(12;16) may correlate with less aggressive clinical behavior. The histology of the FS remained low-grade and the DNA ploidy diploid. The karyotype, however, showed evolution. In both MLS and FS, chromosomal changes thus seem to be a more sensitive marker for tumor progression than histologic changes or DNA ploidy. In one embryonal RMS, karyotypes obtained 7 and 11 yr after the primary diagnosis were different but clearly had a common "progenitor." In one alveolar RMS, the primary and the synchronous lung and lymph node metastases all revealed a t(2;13). The findings in RMS suggest that polyploidization is an early event in tumor evolution, especially in the alveolar subtype, which may be followed by additional chromosomal changes. In addition, DNA ploidy was measured in eight other RMSs. Among the RMSs the embryonal subtype was characterized by DNA aneuploidy, whereas three of the alveolar cases were in the tetraploid range and one was peridiploid. In local recurrences and in metastases changes in DNA index were observed in half the cases.

Leiomyosarcoma in a patient with trisomy 8 mosaicism

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Glucocorticoid-modulated gene expression of tissue- and urinary-type plasminogen activator and plasminogen activator inhibitor 1 and 2

Constitutive gene expression of four components of plasminogen activating enzyme system, urinary and tissue-type plasminogen activator (u-PA and t-PA), plasminogen activator inhibitor 1 (PAI-1) and PAI-2 in HT-1080 human fibrosarcoma cells, was modulated by the synthetic glucocorticoid dexamethasone (Dex, 10(-7) M). More than 90% of u-PA, t-PA and PAI-1 antigen was found in conditioned medium, whereas PAI-2 was mainly cell associated. In 48-h culture supernatants (expressed per 10(6) cells) PAI-1 antigen increased from 350 to 3,300 ng and t-PA from 19 to 38 ng. u-PA and PAI-2 in the same samples decreased from 380 to 46 ng and from 3.5 to 1.8 ng, respectively. Northern blot hybridization and nuclear "Run-on" transcription assays demonstrated that the increase of t-PA and PAI-1 and the decrease of u-PA were associated with equivalent changes of gene template activity. Modulation of u-PA, t-PA and PAI-1 gene expression by Dex was completely blocked by the glucocorticoid antagonist RU 38486, suggesting that all effects were mediated through the glucocorticoid receptor. Cycloheximide, an inhibitor of protein biosynthesis induced a rapid transient increase of t-PA, u-PA and PAI-1 mRNA and a sustained increase of PAI-2 mRNA, but blocked the more long term effects of Dex, suggesting that both constitutive and hormonally regulated maintenance of mRNA steady state levels required protein biosynthesis.