Cellular distribution of phosphofructokinase activity and implications to metabolic regulation in human breast cancer

Neoplastic cells generally present profound changes in glucose metabolism. The mechanisms underlying such process are numerous and all may involve altered cellular hormonal responses. Here we report the first evidence that cellular location of phosphofructokinase activity in human breast cancer tissues is different from the one observed in control tissues and that this phenomenon may be involved in the increased glycolytic flux observed in those cells. Through co-sedimentation techniques, we observed that 60% of phosphofructokinase activity in neoplastic tissues is located in an actin-enriched fraction, against 36% in control tissues. Additionally, metastatic tumor tissues presented a two fold increase in this particulate activity when compared to non-metastatic tumor samples. We propose that the alteration in cellular distribution of phosphofructokinase activity in human breast cancer tissues is a mechanism associated to the process of cell transformation and may be a consequence of the altered hormonal milieu observed in several types of cancer.     

Central and peripheral psychophysiological responses to trauma-related cues in subclinical posttraumatic stress disorder: a pilot study

This study examined verbal-subjective, peripheral and central physiological responses of motor vehicle accident (MVA) survivors with subclinical posttraumatic stress disorder (PTSD), without PTSD symptoms as well as healthy controls. Seven persons of each group were exposed to positive, neutral, accident-related and negative, non-accident-related slides. The verbal-subjective ratings of the slides did not differ between the groups. In contrast to the verbal ratings of the trauma-related materials, the behavioral and physiological responses showed a remarkable dissociation from these reports. The startle responses were enhanced to accident-related slides only in the PTSD group and MVA survivors with PTSD had a significantly lower response to the neutral slides than MVA survivors without PTSD. P200 was lower to positive, neutral and negative slides in the PTSD group compared to both other groups. The late positive complex showed no group-related effects. The data suggest that traumatized persons with PTSD show exaggerated emotional responses to trauma-related stimuli and reduced cognitive responses to several types of stimuli that may interfere with the extinction of the emotional trauma memory.     

Deposition of cellular cementum onto hypoplastic enamel of fluorotic teeth in wild boars (<Emphasis Type="Italic">Sus scrofa</Emphasis> L.)

The nature of deposits present in hypoplastic defects of fluorotic enamel of wild boar teeth was studied by light microscopy and scanning electron microscopy. The fluorotic enamel showed different developmental abnormalities, denoting a severe disturbance of ameloblast function during the secretory stage of amelogenesis. These abnormalities included the occurrence of grossly accentuated incremental lines with associated zones of aprismatic enamel and the presence of different forms of hypoplastic defects. Two types of deposits were present on the hypoplastic enamel: cellular cementum and posteruptively acquired, presumably partially mineralized dental plaque. Coronal cementum is not normally formed in pig teeth. Presence of this tissue in fluorotic teeth of wild boars is seen as indicative of a premature disintegration of the enamel epithelium prior to the completion of amelogenesis. This was supposed to have resulted in a contact of mesenchymal cells of the dental follicle with the surface of the immature enamel and, in consequence, in a differentiation of these cells into cementoblasts. To our knowledge, this is the first study reporting the formation of coronal cementum as part of the spectrum of pathological changes in fluorotic teeth in a species whose tooth crowns are normally free of cementum.     

POL32, a subunit of the Saccharomyces cerevisiae DNA polymerase δ, defines a link between DNA replication and the mutagenic bypass repair pathway

Pol32 is a subunit of Saccharomyces cerevisiae DNA polymerase δ required in DNA replication and repair. To gain insight into the function of Pol32 and to determine in which repair pathway POL32 may be involved, we extended the analysis of the pol32Δ mutant with respect to UV and methylation sensitivity, UV-induced mutagenesis; and we performed an epistasis analysis of UV sensitivity by combining the pol32Δ with mutations in several genes for postreplication repair (RAD6 group), nucleotide excision repair (RAD3 group) and recombinational repair (RAD52 group). These studies showed that pol32Δ is deficient in UV-induced mutagenesis and place POL32 in the error-prone RAD6/REV3 pathway. We also found that the increase in the CAN1 spontaneous forward mutation of different rad mutators relies entirely or partially on a functional POL32 gene. Moreover, in a two-hybrid screen, we observed that Pol32 interacts with Srs2, a DNA helicase required for DNA replication and mutagenesis. Simultaneous deletion of POL32 and SRS2 dramatically decreases cellular viability at 15 °C and greatly increases cellular sensitivity to hydroxyurea at the permissive temperature. Based on these findings, we propose that POL32 defines a link between the DNA polymerase and helicase activities, and plays a role in the mutagenic bypass repair pathway. Received: 25 May 2000 / Accepted: 3 July 2000     

Trends in pubertal development in Europe

The secular changes in growth and maturation can be seen as indicators of socio-economic and health status. In most European countries the age of onset of puberty and of menarcheal age has been decreasing during the past few decades. The duration of puberty seems also to decrease, though few studies provide sufficient data to support this postulation. The four Dutch nationwide growth surveys are useful examples assessing the secular trend in pubertal development over the past 45 years. Genetic and environmental factors contribute to the secular changes. Environmental factors seem to be the most important. Recently, attention has been given to substances with oestrogen-like actions that are present in nutrients. The possible role of these substances in growth and maturation is discussed.     

Principal components of mania

OBJECTIVE: An alternative to the categorical classification of psychiatric diseases is the dimensional study of the signs and symptoms of psychiatric syndromes. To date, there have been few reports about the dimensions of mania, and the existence of a depressive dimension in mania remains controversial. The aim of this study was to investigate the dimensions of manic disorder by using classical scales to study the signs and symptoms of affective disorders. METHODS: One-hundred and three consecutively admitted inpatients who met DSM IV criteria for bipolar disorder, manic or mixed were rated with the Young Mania Rating Scale (YMRS) and the Hamilton Depression Rating Scale (HDRS-21). A principal components factor analysis of the HDRS-21 and the YMRS was carried out. RESULTS: Factor analysis showed five independent and clinically interpretable factors corresponding to depression, dysphoria, hedonism, psychosis and activation. The distribution of factor scores on the depressive factor was bimodal, whereas it was unimodal on the dysphoric, hedonism and activation factors. Finally, the psychosis factor was not normally distributed. LIMITATIONS: Patients of the sample were all medicated inpatients. CONCLUSIONS: Mania seems to be composed of three core dimensions, i.e. hedonism, dysphoria and activation, and is frequently accompanied by a psychotic and a depressive factor. The existence of a depressive factor suggests that it is essential to evaluate depression during mania, and the distribution of the depressive factor supports the existence of two different states in mania.     

Infection of Tick Cells and Bovine Erythrocytes with One Genotype of the Intracellular Ehrlichia Anaplasma marginale Excludes Infection with Other Genotypes

Anaplasma marginale, a tick-borne rickettsial pathogen of cattle, is endemic in several areas of the United States. Many geographic isolates of A. marginale that occur in the United States are characterized by the major surface protein 1a, which varies in sequence and molecular weight due to different numbers of tandem repeats of 28 or 29 amino acids. Recent studies (G. H. Palmer, F. R. Rurangirwa, and T. F. McElwain, J. Clin. Microbiol. 39:631-635, 2001) of an A. marginale-infected herd of cattle in an area of endemicity demonstrated that multiple msp1α genotypes were present but that only one genotype was found per individual bovine. These findings suggested that infection of cattle with other genotypes was excluded. The present study was undertaken to confirm the phenomenon of infection exclusion of A. marginale genotypes in infected bovine erythrocytes and cultured tick cells. Two tick-transmissible isolates of A. marginale, one from Virginia and one from Oklahoma, were used for these studies. In two separate trials, cattle inoculated with equal doses of the two isolates developed infection with only one genotype. Tick cell cultures inoculated with equal doses of the two isolates became infected with only the Virginia isolate of A. marginale. When cultures were inoculated with different ratios of the Oklahoma and Virginia isolates of A. marginale, the isolate inoculated in the higher ratio became established and excluded infection with the other. When cultures with established infections of one isolate were subsequently infected with the other, only the established isolate was detected. We documented infection exclusion during initial infection in cell culture by labeling each isolate with a different fluorescent dye. After 2 days in culture, only a single isolate was detected per cell by fluorescence microscopy. Finally, when Anaplasma ovis infections were established in cultures that were subsequently inoculated with the Virginia or Oklahoma isolate of A. marginale, A. marginale infection was excluded. These studies confirm that infection exclusion occurs with A. marginale in bovine erythrocytes and tick cells, resulting in the establishment of only one genotype, and appears to be the first report of infection exclusion for Anaplasma and Ehrlichia species.     

The anatomical basis of the osteo-musculo-cutaneous trapezius flap in mandibular reconstruction

The osteo-musculo-cutaneous trapezius flap has seen its indications in mandibular reconstruction reduced since the appearance of micro-anastomotic flaps. However, it may still be useful when the patient has marked atheroma contraindicating a free flap. While the arterial supply of this flap is well known, the same is not true for its venous drainage. The preservation of the accessory nerve and its limits in mandibular reconstruction has been little studied. We carried out a study on 30 subjects (60 cadaveric dissections of trapezius flaps) in order to address these questions. The study has been completed by a surgical series of five patients. The cadaveric study allowed demonstration of the variability of venous drainage of this flap, which depended on the external jugular vein in 80% of cases, the subclavian vein in 12% of cases and on both veins in about 8% of cases. The accessory nerve in one third of cases passed through the middle of the arteriovenous pedicle making its preservation impossible. The segment of the scapular spine allowed reconstruction of about 9 cm of mandible including the mental protuberance in 95% of cases. The surgical study confirmed the data of the cadaveric study and showed the value of this flap when free flaps are contraindicated.     

Endoreduplication in conjunction with tumor progression in an aneuploid laryngeal squamous cell carcinoma

We report the case of a 58-year-old man who presented with a squamous cell carcinoma pT1a G2 of the left vocal cord. Six months after histologically verified complete resection, the patient experienced an endolaryngeal and extralaryngeal local recurrence pT4 pN2b G2. We applied DNA flow cytometry (FCM) and comparative genomic hybridization (CGH) on both primary and recurrent tumor. The primary tumor and the endolaryngeal compartment of the relapse was an aneuploid cell clone with a FCM DNA index of 1.42 and 1.44, respectively. The extralaryngeal compartment showed a shift featuring a DNA index of 2.78. In the primary tumor and in both compartments of the recurrence there was an identical pattern of complex chromosomal imbalances as detected in CGH (CGH karyotype: rev ish enh [8q24.2-q24.3, 10q26.1-q26.3, 11q24-q25, 12q24.2-q23.33,X], dim [4q, 13q14.3-q31], amp[1p36.1-p36.2]). Hence, the recurrence was not associated with further gains and losses of chromosomal material. However, in the anterior part of the recurrence, the aneuploid tumor cell genome had completely doubled, obviously due to endoreduplication. Immunohistochemical analysis of several cell-cycle regulators revealed altered expression of checkpoint proteins, pointing to a complex disturbance in cell-cycle regulation.     

Cationic immune complex arthritis in mice--a new model. Synergistic effect of complement and interleukin-1.

A novel cationic immune-complex-mediated arthritis (ICA) model was developed in mice. The highly cationic protein lysozyme was coupled to poly-L-lysine (PLL) and injected intra-articularly into the knee joint of the mouse, shortly after systemic administration of specific antibodies. A vehement joint inflammation developed, characterized by severe joint swelling and the influx of predominantly polymorphonuclear (PMN) leukocyte. Unique properties were combined in this protein. First, an excellent retention of the antigen in joint structures was found, facilitating sufficient IC formation in the synovial tissue and at the cartilage surface. Secondly, PLL.lysozyme appeared to be a potent inducer of interleukin-1 (IL-1). Similar IL-1 production was measured at 6 hours, in both immune or nonimmune mice. Neutralization with antibodies against either IL-1 alpha or IL-1 beta revealed that IL-1 alpha was the dominant cytokine. Resident cells were responsible for this IL-1 production since a comparable IL-1 signal was measured after intra-articular injection of PLL.lys in neutropenic mice. We further investigated whether IL-1 and complement factors were involved in the onset of this ICA. Neutralizing the IL-1 production with antibodies directed against IL-1 alpha and beta showed a significant decrease in joint swelling. Complement depletion by cobra venom factor also prevented the onset of arthritis for the greater part. Only a minor swelling remained at 6 hours after eliciting arthritis, which was similar to the swelling after injecting the antigen alone and probably reflects IL-1 mediated inflammation. In this study, the authors show a synergistic action of IL-1 and complement in the onset of cationic ICA. Unique properties of the antigen such as excellent retention and its ability to induce IL-1 are combined within one molecule and make this antigen arthritogenic in the presence of antibodies and complement activation.