Perceptual and featural measures of mandarin consonant similarity: Confusion matrices and phonological features dataset

This article presents a comprehensive dataset containing two types of similarity measures for 23 Mandarin consonant phonemes: perceptual and featural measures. The perceptual measures are derived from confusion matrices obtained through native speakers' identification tasks in quiet and noise-masked conditions. Specific perceptual measures, including confusion rate and perceptual distance, are calculated based on these matrices. Additionally, a phonological feature system is proposed to evaluate the featural differences between each pair of consonants, providing insights into phonological similarity. The dataset reveals a significant positive correlation between the perceptual and featural measures of similarity. Furthermore, distance matrices are generated using the perceptual distance data, and a hierarchical cluster dendrogram is plotted using the unweighted pair group method with arithmetic mean (UPGMA). The dendrogram shows five major clusters of consonants. Future studies can refer to this dataset for quantified perceptual measures of Mandarin consonant similarity. This dataset can also be valuable for future research exploring consonant similarity in perceptual and phonological domains, as well as investigating the influence of linguistic and extralinguistic factors on consonant perception.

Variation learning in phonology and morphosyntax

While variation occurs in both phonology and morphosyntax, phonological variation also includes phonetic variation motivated by articulatory or perceptual factors. While learning in both domains is subject to cognitive biases, phonological learning may also be biased by physical factors, which may enhance learnability of phonetically motivated alternations. This study aims to identify whether learning differs when children are exposed to phonological or morphosyntactic patterns with equal complexity. Cantonese-speaking children learned an artificial language involving rounding harmony, where unround [e] or round [o] harmonizes with the following noun, or gender agreement, with feminine and masculine allomorphs lo ~ le. Patterns applied variably in 67% of training items, or categorically. Children were tested on generalization to novel stems. In the categorical learning conditions, participants showed comparable rates of harmony/agreement. In the variable phonological learning conditions, application of harmony exceeded the rate of exposure in training, suggesting the influence of a bias toward phonetically grounded rounding harmony. In the variable morphosyntactic condition, participants applied agreement below the rate of exposure. This finding points to a qualitative difference between learning in the two domains, with phonological (but not morphosyntactic) learning influenced by substantive grounding.

Iconicity in Ideophones: Guessing, Memorizing, and Reassessing

Iconicity, or the resemblance between form and meaning, is often ascribed to a special status and contrasted with default assumptions of arbitrariness in spoken language. But does iconicity in spoken language have a special status when it comes to learnability? A simple way to gauge learnability is to see how well something is retrieved from memory. We can further contrast this with guessability, to see (1) whether the ease of guessing the meanings of ideophones outperforms the rate at which they are remembered; and (2) how willing participants' are to reassess what they were taught in a prior task-a novel contribution of this study. We replicate prior guessing and memory tasks using ideophones and adjectives from Japanese, Korean, and Igbo. Our results show that although native Cantonese speakers guessed ideophone meanings above chance level, they memorized both ideophones and adjectives with comparable accuracy. However, response time data show that participants took significantly longer to respond correctly to adjective-meaning pairs-indicating a discrepancy in a cognitive effort that favored the recognition of ideophones. In a follow-up reassessment task, participants who were taught foil translations were more likely to choose the true translations for ideophones rather than adjectives. By comparing the findings from our guessing and memory tasks, we conclude that iconicity is more accessible if a task requires participants to actively seek out sound-meaning associations.

Variation awaiting bias: Substantively biased learning of vowel harmony variation

This article examines whether children alter a variable phonological pattern in an artificial language towards a phonetically-natural form. We address acquisition of a variable rounding harmony pattern through the use of two artificial languages; one with dominant harmony pattern, and another with dominant non-harmony pattern. Overall, children favor harmony pattern in their production of the languages. In the language where harmony is non-dominant, children's subsequent production entirely reverses the pattern so that harmony predominates. This differs starkly from adults. Our results compare to the regularization found in child learning of morphosyntactic variation, suggesting a role for naturalness in variable phonological learning.

Phonetically Grounded Structural Bias in Learning Tonal Alternations

This study investigates the hypothesis that tone alternation directionality becomes a basis of structural bias for tone alternation learning, where “structural bias” refers to a tendency to prefer uni-directional tone deletions to bi-directional ones. Two experiments were conducted. In the first, Mandarin speakers learned three artificial languages, with bi-directional tone deletions, uni-directional, left-dominant deletions, and uni-directional, right-dominant deletions, respectively. The results showed a learning bias toward uni-directional, right-dominant patterns. As Mandarin tone sandhi is right-dominant while Cantonese tone change is lexically restricted and does not have directionality asymmetry, a follow-up experiment trained Cantonese speakers either on left- or right-dominant deletions to see whether the right-dominant preference was due to L1 transfer from Mandarin. The results of the experiment also showed a learning bias toward right-dominant patterns. We argue that structural simplicity affects tone deletion learning but the simplicity should be grounded on phonetics factors, such as syllables’ contour-tone bearing ability. The experimental results are consistent with the findings of a survey on other types of tone alternation’s directionality, i.e., tone sandhi across 17 Chinese varieties. This suggests that the directionality asymmetry found across different tone alternations reflects a phonetically grounded structural learning bias.

The reality of hierarchical morphological structure in multimorphemic words

This cross-modal priming study is one of the first to empirically test the long-held assumption that individual morphemes of multimorphemic words are represented according to a hierarchical structure. The results here support the psychological reality behind this assumption: Recognition of trimorphemic words (e.g., unkindness or [[un-[kind]]-ness]) was significantly facilitated by prior processing of their substrings when the substrings served as morphological constituents of the target words (e.g., unkind), but not when the substrings were not morphological constituents of the target words (e.g., kindness). This morphological structural priming occurred independently of the linear positions of morphological constituents.

Visual Speech Perception Cues Constrain Patterns of Articulatory Variation and Sound Change

What are the factors that contribute to (or inhibit) diachronic sound change? While acoustically motivated sound changes are well-documented, research on the articulatory and audiovisual-perceptual aspects of sound change is limited. This paper investigates the interaction of articulatory variation and audiovisual speech perception in the Northern Cities Vowel Shift (NCVS), a pattern of sound change observed in the Great Lakes region of the United States. We focus specifically on the maintenance of the contrast between the vowels /ɑ/ and /ɔ/, both of which are fronted as a result of the NCVS. We present results from two experiments designed to test how the NCVS is produced and perceived. In the first experiment, we present data from an articulatory and acoustic analysis of the production of fronted /ɑ/ and /ɔ/. We find that some speakers distinguish /ɔ/ from /ɑ/ with a combination of both tongue position and lip rounding, while others do so using either tongue position or lip rounding alone. For speakers who distinguish /ɔ/ from /ɑ/ along only one articulatory dimension, /ɑ/ and /ɔ/ are acoustically more similar than for speakers who produce multiple articulatory distinctions. While all three groups of speakers maintain some degree of acoustic contrast between the vowels, the question is raised as to whether these articulatory strategies differ in their perceptibility. In the perception experiment, we test the hypothesis that visual speech cues play a role in maintaining contrast between the two sounds. The results of this experiment suggest that articulatory configurations in which /ɔ/ is produced with unround lips are perceptually weaker than those in which /ɔ/ is produced with rounding, even though these configurations result in acoustically similar output. We argue that these findings have implications for theories of sound change and variation in at least two respects: (1) visual cues can shape phonological systems through misperception-based sound change, and (2) phonological systems may be optimized not only for auditory but also for visual perceptibility.

A dendritic cell targeted vaccine induces long-term HIV-specific immunity within the gastrointestinal tract

Despite significant therapeutic advances for HIV-1 infected individuals, a preventative HIV-1 vaccine remains elusive. Studies focusing on early transmission events, including the observation that there is a profound loss of gastrointestinal (GI) CD4(+) T cells during acute HIV-1 infection, highlight the importance of inducing HIV-specific immunity within the gut. Here we report on the generation of cellular and humoral immune responses in the intestines by a mucosally administered, dendritic cell (DC) targeted vaccine. Our results show that nasally delivered α-CD205-p24 vaccine in combination with polyICLC, induced polyfunctional immune responses within naso-pulmonary lymphoid sites that disseminated widely to systemic and mucosal (GI tract and the vaginal epithelium) sites. Qualitatively, while α-CD205-p24 prime-boost immunization generated CD4(+) T-cell responses, heterologous prime-boost immunization with α-CD205-p24 and NYVAC gag-p24 generated high levels of HIV-specific CD4(+) and CD8(+) T cells within the GI tract. Finally, DC-targeting enhanced the amplitude and longevity of vaccine-induced immune responses in the GI tract. This is the first report of a nasally delivered, DC-targeted vaccine to generate HIV-specific immune responses in the GI tract and will potentially inform the design of preventative approaches against HIV-1 and other mucosal infections.

Human periodontal ligament stem cells suppress T-cell proliferation via down-regulation of non-classical major histocompatibility complex-like glycoprotein CD1b on dendritic cells

BACKGROUND AND OBJECTIVE

Periodontal ligament stem cells (PDLSCs) from the periodontal ligament tissue were recently identified as mesenchymal stem cells (MSCs). The capabilities of PDLSCs in periodontal tissue or bone regeneration have been reported, but their immunomodulatory role in T-cell immune responses via dendritic cells (DCs), known as the most potent antigen-presenting cell, has not been studied. The aim of this study is to understand the immunological function of homogeneous human STRO-1⁺ CD146⁺ PDLSCs in DC-mediated T-cell immune responses to modulate the periodontal disease process.

MATERIAL AND METHODS

We utilized highly purified (> 95%) human STRO-1⁺ CD146⁺ PDLSCs and human bone marrow mesenchymal stem cells (BMSCs). Each stem cell was co-cultured with human monocyte-derived DCs in the presence of lipopolysaccharide isolated from Porphyromonas gingivalis, a major pathogenic bacterium responsible for periodontal disease, in vitro to examine the immunological effect of each stem cell on DCs and DC-mediated T-cell proliferation.

RESULTS

We discovered that STRO-1⁺ CD146⁺ PDLSCs, as well as BMSCs, significantly decreased the level of non-classical major histocompatibility complex glycoprotein CD1b on DCs, resulting in defective T-cell proliferation, whereas most human leukocyte antigens and the co-stimulatory molecules CD80 and CD86 in/on DCs were not significantly affected by the presence of BMSCs or STRO-1⁺ CD146⁺ PDLSCs.

CONCLUSIONS

This study unveiled an immunomodulatory role of STRO-1⁺ CD146⁺ PDLSCs in negatively regulating DC-mediated T-cell immune responses, demonstrating their potential to be utilized in promising new stem cell therapies.

Symmetry-breaking Hopf bifurcations to 1-, 2-, and 3-tori in small-aspect-ratio counterrotating Taylor-Couette flow

The nonlinear dynamics of Taylor-Couette flow in a small-aspect-ratio wide-gap annulus in the counterrotating regime is investigated by solving the full three-dimensional Navier-Stokes equations. The system is invariant under arbitrary rotations about the axis, reflection about the annulus midplane, and time translations. A systematic investigation is presented both in terms of the flow physics elucidated from the numerical simulations and from a dynamical system perspective provided by equivariant normal form theory. The dynamics are primarily associated with the behavior of the jet of angular momentum that emerges from the inner cylinder boundary layer at about the midplane. The sequence of bifurcations as the differential rotation is increased consists of an axisymmetric Hopf bifurcation breaking the reflection symmetry of the basic state leading to an axisymmetric limit cycle with a half-period-flip spatiotemporal symmetry. This undergoes a Hopf bifurcation breaking axisymmetry, leading to quasiperiodic solutions evolving on a 2-torus that is setwise symmetric. These undergo a further Hopf bifurcation, introducing a third incommensurate frequency leading to a 3-torus that is also setwise symmetric. On the 3-torus, as the differential rotation is further increased, a saddle-node-invariant-circle bifurcation takes place, destroying the 3-torus and leaving a pair of symmetrically related 2-tori states on which all symmetries of the system have been broken.

Breast tomosynthesis and digital mammography: a comparison of diagnostic accuracy

OBJECTIVE

Our aim was to compare the ability of radiologists to detect breast cancers using one-view breast tomosynthesis (BT) and two-view digital mammography (DM) in an enriched population of diseased patients and benign and/or healthy patients.

METHODS

All participants gave informed consent. The BT and DM examinations were performed with about the same average glandular dose to the breast. The study population comprised patients with subtle signs of malignancy seen on DM and/or ultrasonography. Ground truth was established by pathology, needle biopsy and/or by 1-year follow-up by mammography, which retrospectively resulted in 89 diseased breasts (1 breast per patient) with 95 malignant lesions and 96 healthy or benign breasts. Two experienced radiologists, who were not participants in the study, determined the locations of the malignant lesions. Five radiologists, experienced in mammography, interpreted the cases independently in a free-response study. The data were analysed by the receiver operating characteristic (ROC) and jackknife alternative free-response ROC (JAFROC) methods, regarding both readers and cases as random effects.

RESULTS

The diagnostic accuracy of BT was significantly better than that of DM (JAFROC: p=0.0031, ROC: p=0.0415). The average sensitivity of BT was higher than that of DM (∼90% vs ∼79%; 95% confidence interval of difference: 0.036, 0.108) while the average false-positive fraction was not significantly different (95% confidence interval of difference: -0.117, 0.010).

CONCLUSION

The diagnostic accuracy of BT was superior to DM in an enriched population.

Employment status and work-related difficulties in family caregivers of terminal cancer patients compared with the general population

9580

Background: This study was aimed to investigate the employment status and work-related difficulties among family caregiver of terminal cancer patients compared with the general population. Methods: A survey was administered to 381 family caregivers of terminal cancer patients at 11hospitals and 994 general populations aged more than 18 years. Results: Family caregivers of terminal cancer patients were female (66.7%) and the patient's spouse (50.9%), with mean age of 46.8years (SD, 13.5). 212(56.1%) were working before cancer diagnosis, however, only 133(36.3%) continued working currently. Compared with the general population, 233(63.7%)family caregivers of terminal cancer patients were more likely to be not working (adjusted odds ratio [aOR] =2.39; 95% confidence interval [95%CI] = 1.73 to 3.29).Those who continued working reported more easy fatigability (40.6% vs 22.4%) and reduced working hours (20.3% vs 2.1%) than general population. For those doing housework, caregiving itself (56.4%) were identified to be the most common difficulties, followed by easy fatigability (32.3%). Major reasons for not working were providing care to the terminal cancer patients (24.0%). Older age (aOR=10.37; 95%CI=2.80 to 38.41), female sex (aOR=4.28; 95%CI=2.25 to 8.13), lower household income (aOR=2.19; 95%CI=1.19 to 4.06), bearing medical cost by other than spouse (aOR=2.10; 95%CI=1.05 to 4.19), and low performance status of the patients (aOR=2.00; 95%CI=1.01 to 3.95) were significantly associated with not working. Conclusions: When compared to the general population, family caregivers of terminal cancer patients were at risk job loss from their caregiving burden, and caregiving and easy fatigability were the major work-related difficulties. Our study might help make a strategy to reduce job loss for family caregivers' caregiving burden.

No significant financial relationships to disclose.

The clinical significance of oophorectomy in gastric patients

e15646

Background: The oophorectomy in isolated metastasis of ovary can lead to long term survival in patients with gastric cancer, but the clinical significance of oophorectomy in stage IV gastric cancer patients is not known well in this time. Methods: We reviewed the medical record of the 55 gastric cancer patients who were metastasis or recurrent in ovary at Dongsan Medical Center, Kimyung University School of Medicine, Daegu, Korea from 1985 to 2008. Results: Twenty-one patients were metastasis to ovary at the time of diagnosis of gastric cancer, and 34 patients were recurrent in ovary after the gastric resection. The mean age was 45.3 ± 11.6 years in metastatic cancer and 46.8 ±12.6 years in recurrent cancer patients. The stage at the time of gastric resection in 34 recurrent patients were I in 3, II in 1, III in 18, and IV in 10. Adjuvant chemotherapy were performed in 26 (76.5%) patients. Oophorectomy were performed in 33 (97.1%) of recurrent cancer, and 17 (81.0%) of metastatic cancer. The 1-year and 2-year survival rate of metastatic cancer were 14.7%, and 0%, and 1-year, 2-year, and 3-year survival rate of recurrent cancer were 47.2%, 18.1%, and 0%, respectively. The median survival duration of metastatic cancer were 8.9 ±1.0 months, and recurrent cancer were 11.4 ±2.3 months. Recurrent cancer were better survival than metastatic cancer patients (p=0.014). The long-term survival (over 2 years) was noted in 5 patients of recurrent cancer patients. The stage of gastric cancer was correlated to overall survival time in total patients (p=0.028). But, the relapse-free survival time after gastrectomy is the only factor to predict survival duration after oophorectomy in recurrent cancer patients (p=0.029). Age, stage of gastric cancer, extent of involvement of ovary, and systemic chemotherapy were not related to survival time of recurrent cancer patients. Conclusions: The survival time in patients with oophorectomy in recurrent gastric cancer was correlated to relapse-free survival time after gastric resection.

No significant financial relationships to disclose.

Multicenter phase II study of docetaxel plus oxaliplatin combination chemotherapy in patients with advanced gastric cancer

15026

Background: The present study was conducted to evaluate the efficacy and safety of a combination regimen of docetaxel plus oxaliplatin in patients with advanced gastric cancer. Methods: Patients with previously untreated metastatic or recurrent, measurable gastric cancer received intravenous docetaxel 65 mg/m2 plus oxaliplatin (Oxalpla®, Yuhan.Co. Seoul, Korea) 120 mg/m2 on days 1 in a 3-week cycle. Treatment was continued until disease progression, patient refusal, or an unacceptable toxicity up to 9 cycles. Results: Forty-two patients were enrolled in the current study. Of these, 39 were assessable for efficacy and 41 assessable for toxicity. Seventeen partial responses were confirmed, giving an overall response rate of 40.5% (95% CI: 26.0% to 54.1%, intention-to-treat analysis). At a median follow-up of 160.5 days, the median time to progression was 6.1 months, whereas median overall survival was not reached yet. Grade 3/4 neutropenia occurred in 10 patients, plus febrile neutropenia was observed in 3 patients. Most common non-hamatologic toxicity was nausea (grade 1/2 56.9%). There were two treatment-related deaths. Conclusions: Docetaxel and oxaliplatin combination was found to be well-tolerated and effective in patients with advanced gastric cancer. Accordingly, this regimen can be regarded as an important first-line treatment option for advanced gastric cancer.

No significant financial relationships to disclose.

Use of absolute lymphocyte counts to predict response to chemotherapy and survival in diffuse large B-cell lymphoma

8082

Background: Absolute lymphocyte counts (ALCs) at diagnosis has been shown to be an independent prognostic factor in patients with follicular lymphoma (FL) although the precise mechanism was not fully elucidated. The current study evaluated the impact of Absolute lymphocyte counts (ALCs) at diagnosis in patients with diffuse large B-cell lymphoma (DLBCL) on the response to chemotherapy and survival. Methods: The treatment outcomes of the patients receiving CHOP (n=101) or R-CHOP chemotherapy (n=122) were compared according to ALCs at diagnosis (<1.0 vs. = 1.0×109/L). Results: Forty-two patients (19%) had a lower ALC count at diagnosis (CHOP, 23 [23%]; R-CHOP, 19 [16%]). The lower ALCs showed a good correlation with IPI (p<0.001), performance (p<0.001), LDH (p<0.001), stage (p=0.004), extranodal involvement (p=0.011), but not with age or sex. A significant difference of response rate was noted according to ALCs in favor of a higher ALCs (CR: 80% vs. 60%, p=0.005; ORR: 93% vs. 78%, p=0.003). In addition, event-free survival (EFS) was worse in a lower ALC group than higher ALC group: median duration of EFS, 1,773 days vs. 326 days (p<0.001). The OS was also in favor of a higher ALC group: median duration of OS, 3,000 days vs. 695 days (p<0.001). In multivariate analysis, ALC at diagnosis was an independent predictive factor for CR (HR 2.717, p=0.009) and prognostic factor for EFS (HR 2.148, p=0.004) or OS (HR 2.863, p=0.002). Conclusion: The ALCs at diagnosis appears to predict the survival of DLBCL patients. Our findings suggested that the ALCs at diagnosis may reflect host's immune status against DLBCL, implying that immune system of host will play a critical role on survival of DLBCL patients.

No significant financial relationships to disclose.

Prognostic significance of immunohistochemical expression of Rb gene product in operable breast cancer

21121

Background: The aim of this study was to investigate the prognostic significance of the expression of Rb gene product in operable invasive breast cancer by performing immunohistochemical analysis. Methods: Between January 1993 and December 2001, 212 operable invasive breast cancer patients underwent immunohistochemical staining for Rb, and we retrospectively analyzed these results together with the clinical outcomes. Results: The overexpression of p53 was detected in 72.7% of the cases. The overexpression of Rb was correlated with positive hormonal receptor (p=0.000), and inversely correlated with lymph node metastasis (p=0.017) and vascular invasion (p=0.004). The tumor size, tumor histology, histologic grade, and tumor stage were not related to the overexpression of p53. Multivariate Cox regression analysis indicate that lymph node metastasis and tumor size were the significant prognostic factors for overall survival; lymph node metastasis was the significant prognostic factor for relapse free survival. On the subgroup analysis, the Rb expressors showed better 7-year overall survival (98.5% vs. 81.5%, respectively, p=0.005) and relapse free survival (94.1% vs. 77.4%, respectively, p=0.021) than did the p53 non-overexpressors for the patients without lymph node metastasis. However, for the patients with lymph node metastasis, the survival rates were not different for both the Rb expressors and the Rb non-expressors. Conclusions: Immunohistochemical staining of the Rb gene product was an independent prognostic factor for predicting survival of the lymph node negative operable breast cancer patients.

No significant financial relationships to disclose.

Overexpression of the osteopontin correlates with the aggressiveness of endometrial cancer

5038

Background: To test the hypothesis that expression of osteopontin (OPN), an integrin-binding glycoprotein, can independently predict the potential aggressiveness of endometrial cancer. We studied OPN expression in endometrial cell carcinomas and correlated OPN expression levels with clinicopathologic tumor features. Methods: The status of OPN expression in benign and malignant endometrial cancer cell lines and tissues was analyzed by Western blot and immunohistochemistry. Nonparametric Spearman’s correlation coefficient method was used to assess the statistical significance of the correlation between clinicopathologic characteristics of tumor and OPN expression. Results: An increased expression of OPN was observed in the endometrial cancer compared to normal endometrial tissue samples. When the level of OPN in normal tissue was set at 1, its level in benign endometrial hyperplasia was slightly increased at 1.2, whereas the OPN level in the highly malignant endometrial carcinoma tissue was greatly increased by nearly 3- 5 folds. Amongst the 70 cases examined immunocytochemically, of the 23 grade 1 endometrial carcinomas, 6 were unstained and 12 stained weakly positive (+). For the 20 grade 3 or serous type endometrial carcinomas analyzed, 8 (40%) stained strongly positive (+++), 8 (40%) stained moderately positive (++) and 1 stained weakly positive (+). These results showed that the level of OPN expressed between grade 1 and grde 3 or more was significantly different (Spearman’s correlation coefficient method, p = 0.001). Kaplan-Meier survival analysis showed that the increased level of OPN expression was significantly associated with reduced survival time of the patients. Conclusions: The results suggest that the increased OPN level may be involved in the malignant transformation of endometrial adenocarcinoma cells and OPN expression level is an important determinant for patient survival.

No significant financial relationships to disclose.

Multiple primary cancers in patients with non-Hodgkin’s lymphoma

17562

Background: Multiple primary malignant tumors have been documented with increased frequency over the last two decades. An analysis of other primary cancers in individuals with non-Hodgkin’s lymphoma (NHL) can help to elucidate this cancer epidemics and etiology. Methods: The occurrence of multiple malignancy was studied in patients with NHL from 1985 to 2005. Results: One or more additional cancers were observed in 19 patients. Seven were diagnosed prior to, 5 concomitantly with, and 7 after the diagnosis of NHL. The diagnosis of 5 synchronous primary cancer were rectal cancer, squamous cell esophageal cancer, prostatic cancer, transitional cell bladder cancer, and non-small cell lung cancer. Each cases of colon cancer, breast cancer, hepatoma, small cell lung cancer, stomach cancer, cervical cancer, and rhabdomyosarcoma were diagnosed prior to NHL, and the second primary cancers were two squamous skin cancer and each cases of melanoma, colon cancer, thyroid cancer, adenocarcinoma of the salivary gland, and cholangiocarcinoma. The mean age of synchronous cases was 68.2 ± 4.8 years-old, and all 5 cases were primary extranodal NHL (2 gastric, 1 nasopharynx, 1 nasal, 1 rectal) and pathologic diagnosis were diffuse large cell in 4 cases and extranasal NK/T cell type in one case. The mean age of the second primary NHL was 57.6 ± 11.4 years-old, and 5 of 7 cases were extranodal origin (each one case of colon, tonsil, tongue, stomach, and CNS), and were diagnosed 11, 19, 24, 72, 73, 101, 168 months after the diagnosis of variable cancers. The mean age of the second primary cancer was 46.9 ± 15.9 years-old, and 3 of 7 cases were extranodal origin (2 gastric and 1 tonsil), and were diagnosed 55, 73, 75, 99, 144, 156, 161 months after the diagnosis of NHL. Conclusions: The synchronous cases of NHL were more older and more frequent extranodal manifestations than metachronous cases.

No significant financial relationships to disclose.

Palliative chemotherapy preferences and factors that influence patient choice in advanced cancer

16010

Background: We conducted this prospective study to determine the treatment preference of patients receiving chemotherapy in a palliative setting. We investigated the survival threshold for justifying toxicity, the factors influencing individual preference for chemotherapy, and the attitude of patients towards randomized trials. Methods: 138 patients (median age, 58 years; 73% male) with advanced cancer who had received at least one cycle of palliative chemotherapy were recruited. General demographic information, patient preferences for palliative chemotherapy, and randomized trials were determined using structured patient interviews. Results: The median age was 58 years (range, 25–77 years), and the majority of the study population were male (73%). 73 patients (60.1%) answered that they had some support by dependents. Fewer than half were given information about the impact of their chemotherapy on survival (n = 64, 48.1%), and just over one third of patients (n = 53, 40.5%) were presented with an alternative to anticancer therapy, such as supportive care (p < 0.001). While 75.7% of patients agreed to receive chemotherapy with mild toxicity, only 57.9% of patients agreed to chemotherapy with severe toxicity (p = 0.002). The median survival threshold was 12 months for mild toxicity, and 21 months for severe toxicity. Patients who experienced improvement of symptoms or quality of life were more likely to judge the treatment as acceptable. 105 patients (78.4%) refused a clinical trial with randomization between a conventional chemotherapy and supportive care. There were 85 patients (62.6%) that would refuse randomization between conventional chemotherapy and investigational chemotherapy. Finally, 58.6% of patients agreed to participate in trials with investigational agents. Conclusions: In the palliative setting, a discussion of prognosis and the merits of chemotherapy is a necessary part of the treatment decision-making processes, and choosing the proper treatment for cancer patients. Individual preferences assume greater importance in this setting. Randomized trials must be carefully designed with a priori equipoise.

No significant financial relationships to disclose.

Unusual ferromagnetic couplings in single end-to-end azide-bridged cobalt(II) and nickel(II) chain systems

Two new one-dimensional single azide-bridged metal(II) compounds [[M(5-methylpyrazole)4(N3)]n](ClO4)n(H2O)n [M = Co (1a), Ni (2a)] were prepared by treating an M(II) ion with stoichiometric amount of sodium azide in the presence of four equivalents of the 3(5)-methylpyrazole ligand. The isostructural compounds 1a and 2a crystallize in the monoclinic space group P2(1)/n. The azide bridging ligands have a unique end-to-end coordination mode that brings two neighboring metal centers into a cis-position with respect to the azide unit to form single end-to-end azide-bridged cobalt(II) and nickel(II) chains. The two neighboring metal atoms at inversion centers adopt octahedral environments with four equatorial 3(5)-methylpyrazole ligands and two axial azide bridges. Two adjacent equatorial least-squares planes form dihedral angles of 60.5 degrees and 60.6 degrees for Co and Ni, respectively. In addition, the metal-azide-metal units form large M-N3-M torsion angles, which are magnetically important geometrical parameters, of 71.6 degrees for M=Co and 75.7 degrees for M=Ni. It should also be noted that the M-N-N angles associated with end-to-end azide group, another magnetically important structural parameter, fall into the experimentally observed range of 120-140 degrees as 128.3(3) and 147.8(3) degrees for cobalt species and 128.4(2) and 146.1(3) degrees for nickel species; these values deviate from the theoretical value of around 164 degrees at which the incidental orthogonality is achieved under the torsion angle of 0 degrees. The compounds 1a and 2a have unique magnetic properties of ferromagnetism, zero-field splitting, and spin canting. The MO calculations indicate that the quasiorthogonality between the magnetic orbitals of metal ions and the p atomic orbitals of the bridging azide is possible in the observed structures and leads to the ferromagnetism. The spin canting related to the perturbation of ferromagnetism arises from the magnetic anisotropy and antisymmetric interactions judged by the structural parameters of the zero-field splitting and the tilted MN4 planes in a chain. The enhancement of magnetic interactions was accomplished by dehydrating the chain compounds to afford two soft magnets with critical temperature T(C) and coercive field of 2 K and 35 G for 1b and 2.3 K and 20 G for 2b, respectively.

Novel families of three-component reversible redox cycles involving cage deformation via intramolecular redox reaction: tetrathiolate-bridged dinuclear molybda- and tungstacarboranes

The synthesis and structural analysis of two novel families of three-component reversible redox cycles [(C(2)B(9)H(11))M(mu-SPh)(2)](2)(n)PPN(n) (M = Mo, n = 2-, 2; 1-, 3; 0, 4; and M = W, n = 2-, 6; 1-, 7; 0, 8), where the cleavage and re-formation of the carborane cage C-C bond is observed during the redox reaction, are reported. Electronic saturation of the metal center (18e center) and the lack of bulky substituents on the carborane cage suggest that the deformed carborane cages in 2.PPN(2), 6.PPN(2), and 7.PPN invoke a new kind of deformed cage ("semicloso" framework). The XPS results show that the unprecedented competition for electron density between the metal center and the carborane cage is involved in the cleavage and formation of the carborane C-C bond.

Evidence for estradiol-induced apoptosis and dysregulated T cell maturation in the thymus

In an attempt to delineate the immunological alterations that may occur following treatment with estrogen, groups of C57BL/6 mice were treated with 75mg/kg body weight of beta-estradiol-17-valerate (E2) or the vehicle. The thymus from these mice were harvested on days 1, 4 and 7 following treatment. The thymocytes from E2-treated mice when cultured in vitro for 24h, showed increased levels of apoptosis when compared to controls. The apoptosis was demonstrable by both TUNEL assay and AnnexinV/propidium iodide (PI) staining. Also, thymic atrophy and increased apoptosis of thymocytes when cultured in vitro were seen when lower doses of E2 (5mg/kg) were administered. The thymus from E2-treated mice on days 4 and 7 also showed a decrease in the percentage of CD4(+)CD8(+) (DP) T cells and an increase in the percentage of CD4(-)CD8(-) (DN), CD4(+) and CD8(+) T cells. However, the total cellularity of all T cell subsets in the thymus was decreased following E2 treatment. Earlier studies from our laboratory and elsewhere have demonstrated that in thymocytes undergoing apoptosis, there is increased expression of surface markers including CD3, alphabetaTCR and CD44 with a simultaneous decrease in the expression of J11d. Similar changes were observed in thymocytes from mice on days 4 and 7 following E2 treatment. These data therefore confirmed that the thymocytes were indeed undergoing apoptosis following E2 treatment. Together, our studies suggest for the first time that estrogen may induce thymic atrophy by triggering apoptosis.

CD44-deficient mice exhibit enhanced hepatitis after concanavalin A injection: evidence for involvement of CD44 in activation-induced cell death

Administration of Con A induces severe injury to hepatocytes in mice and is considered to be a model for human hepatitis. In the current study, we investigated the role of CD44 in Con A-induced hepatitis. Intravenous administration of Con A (20 mg/kg) caused 100% mortality in C57BL/6 CD44-knockout (KO) mice, although it was not lethal in C57BL/6 CD44 wild-type (WT) mice. Administration of lower doses of Con A (12 mg/kg body weight) into CD44 WT mice induced hepatitis as evident from increased plasma aspartate aminotransferase levels accompanied by active infiltration of mononuclear cells and neutrophils, and significant induction of apoptosis in the liver. Interestingly, CD44 KO mice injected with similar doses of Con A exhibited more severe acute suppurative hepatitis. Transfer of spleen cells from Con A-injected CD44 KO mice into CD44 WT mice induced higher levels of hepatitis when compared with transfer of similar cells from CD44 WT mice into CD44 WT mice. The increased hepatitis seen in CD44 KO mice was accompanied by increased production of cytokines such as TNF-alpha, IL-2 and IFN-gamma, but not Fas or Fas ligand. The increased susceptibility of CD44 KO mice to hepatitis correlated with the observation that T cells from CD44 KO mice were more resistant to activation-induced cell death when compared with the CD44 WT mice. Together, these data demonstrate that activated T cells use CD44 to undergo apoptosis, and dysregulation in this pathway could lead to increased pathogenesis in a number of diseases, including hepatitis.

Synthesis, structures and antitumor activity of the first crown ester-linked bipyridyl platinum complexes

Three new crown ester-linked bipyridine homologs with three, four or five ethylene glycol units, which are bulky and soluble in both hydrophilic and lipophilic media, were synthesized. The reaction of the appropriate macrocycles with K2PtCl4 in water gave yellow cisplatin analogs in good yield. These complexes were converted to carboplatin analogs by exchange of the leaving group. All the compounds were characterized by elemental analysis and various spectroscopic methods. Carboplatin analogs showed good solubility in both hydrophilic and lipophilic media. The crystal structure of 2c, the carboplatin analog with macrocycles containing five ethylene glycol units, was determined by X-ray diffraction: space group P1, a = 9.798(1), b = 12.580(3), c = 13.945(2) A, alpha = 108.61(2), beta = 94.59(1), gamma = 97.42(2) degrees, Z = 2, R = 0.0618. Some of platinum complexes showed a moderate cytotoxic effect on both murine leukemia L1210 and P388 even though they do not have any NH proton.

Investigation of Coordinational Properties of Europium(III) Complexes with Picolinic Acid Using Eu(III) Excitation Spectroscopy

The 7F0 --> 5D0 excitation spectra of Eu(III) complexed with picolinic acid were investigated using Eu(III) excitation spectroscopy. Six overlapping peaks are seen in the excitation spectra, indicating the formation of six species. The structures of the six species are proposed here and described in terms of both coordination by carboxylate and N-chelation. Copyright 1999 Academic Press.