Expression of cyclin-dependent kinase 5 and associated cyclins in Leydig and Sertoli cells of the testis

Sixty patients with a sudden onset of motor disability were assessed for illness behavior and depression. In 30 of the patients, etiology was attributed to a definite structural lesion. The remaining 30 patients were diagnosed as having conversion disorder. The Illness Behaviour Questionnaire (IBQ) and the Hamilton Rating Depression Scale (HRDS) were used as instruments for assessment. The mean HRDS score was significantly higher in the conversion group, indicating a higher degree of affective disease in these patients. According to the results of the IBQ, the patients with conversion disorder showed a higher degree of irritability, disease conviction, and phobic preoccupation, and also, to a greater extent, rejected psychological explanations for their symptoms. Denial was high in both patient groups, coexisting with affective symptoms in the conversion patients but not in the neurological patients. Although valuable information could be extracted from the IBQ, it was not found to be a reliable instrument for distinguishing between psychogenic and organic causes of motor disability.     

AlGaN-GaN HEMTs on Si with power density performance of 1.9 W/mm at 10 GHz

AlGaN-GaN high electron mobility transistors (HEMTs) on silicon substrate are fabricated. The device with a gate length of 0.3-/spl mu/m and a total gate periphery of 300 /spl mu/m, exhibits a maximum drain current density of 925 mA/mm at V/sub GS/=0 V and V/sub DS/=5 V with an extrinsic transconductance (g/sub m/) of about 250 mS/mm. At 10 GHz, an output power density of 1.9 W/mm associated to a power-added efficiency of 18% and a linear gain of 16 dB are achieved at a drain bias of 30 V. To our knowledge, these power results represent the highest output power density ever reported at this frequency on GaN HEMT grown on silicon substrates.     

Evidence that HLA class II-restricted human CD4+ T cells specific to p53 self peptides respond to p53 proteins of both wild and mutant forms

By stimulating peripheral blood mononuclear cells of four healthy donors with a mixture of overlapping peptides representing the core domain of p53, we established two CD4+ alphabeta T cell clones and four lines that recognized wild-type and mutant p53 proteins as well as p53 self peptides in an HLA class II-restricted fashion. Two T cell lines established from two unrelated donors reacted to the p53 peptide (p)153-166 and p108-122, respectively, in the context of DP5 molecules. Two T cell clones established from two other unrelated donors were specific for p193-204 in the context of DRB1*1401 and for p153-165 in the context of DP5, respectively. These two T cell clones responded almost equally to both wild-type and four mutant recombinant p53 proteins. The proliferative responses of these T cell clones to p53 recombinant proteins were augmented by heat denaturing, thereby suggesting that altered conformation of the protein facilitates proteolytic processing to produce antigenic peptides. The DRB1*1401-restricted T cell clone specific for p193-204 killed a B lymphoblastoid cell line homozygous for HLA-DRB1*1401 when the cell line was pre-pulsed with p53 protein as well as peptide. These results indicate that CD4+ T cells reactive to p53 do exist in healthy individuals and the epitopes are probably ignored by the immune system under physiological conditions. It is suggested that such epitopes stimulate T cells to induce anti-p53 antibody production in cancer patients as previously reported by others. The possible involvement of p53-reactive T cells in anti-tumor immunity is discussed.     

Characteristics and efficiency of glutamine production by coupling of a bacterial glutamine synthetase reaction with the alcoholic fermentation system of baker's yeast

Glutamine production with bacterial glutamine synthetase (GS) and the sugar-fermenting system of baker's yeast for ATP regeneration was investigated by determining the product yield obtained with the energy source for ATP regeneration (i.e., glucose) for yeast fermentation. Fructose 1,6-bisphosphate was accumulated temporarily prior to the formation of glutamine in mixtures which consisted of dried yeast cells, GS, their substrate (glucose and glutamate and ammonia), inorganic phosphate, and cofactors. By an increase in the amounts of GS and inorganic phosphate, the amounts of glutamine formed increased to 19 to 54 g/liter, with a yield increase of 69 to 72% based on the energy source (glucose) for ATP regeneration. The analyses of sugar fermentation of the yeast in the glutamine-producing mixtures suggested that the apparent hydrolysis of ATP by a futile cycle(s) at the early stage of glycolysis in the yeast cells reduces the efficiency of ATP utilization. Inorganic phosphate inhibits phosphatase(s) and thus improves glutamine yield. However, the analyses of GS activity in the glutamine-producing mixtures suggested that the higher concentration of inorganic phosphate as well as the limited amount of ATP-ADP caused the low reactivity of GS in the glutamine-producing mixtures. A result suggestive of improved glutamine yield under the conditions with lower concentrations of inorganic phosphate was obtained by using a yeast mutant strain that had low assimilating ability for glycerol and ethanol. In the mutant, the activity of the enzymes involved in gluconeogenesis, especially fructose 1,6-bisphosphatase, was lower than that in the wild-type strain.     

Peripheral blood stem cell autografts for the treatment of children over 1 year old with stage IV neuroblastoma: a long-term follow-up

This is the first report of the long-term therapeutic results in 22 children more than 1 year old with stage IV neuroblastoma who were treated with autologous peripheral blood stem cell transplantation (PBSCT). The median age of the patients at PBSCT was 4 years (1 to 10 years) and seven of the 17 patients who were evaluated for N-myc amplification were positive. PBSC were collected by a median of four aphereses per patient. The patients underwent PBSCT from 6 to 21 months after the start of therapy (median 10.5 months) at which time 13 patients were in CR, seven were in PR, and two had refractory disease. Multi-drug therapy using the 'high-MEC' regimen consisting of carboplatinum (400 mg/m2) and VP-16 (200 mg/m2) on days -7 to -4, and melphalan (90 mg/m2) on days -3 and -2, was the primary cytoreductive regimen. The median number of infused MNC and CFU-GM was, respectively, 4.3 x 10(8)/kg and 2.4 x 10(5)/kg. After PBSCT, three patients died of regimen-related toxicities and one patient who was transplanted with refractory disease died of disease progression without any benefit from transplantation. Hematological recovery was evaluated in 21 patients, excluding one early death. The median number of days required to achieve an AGC of >0.5 x 10(9)/l and platelet count of >50 x 10(9)/l were, respectively, 11 and 46. Eleven patients relapsed 3 to 50 months after PBSCT, and currently seven patients (5/13 who were transplanted in CR and 2/7 in PR) are surviving disease-free at 52 to 84 months. Although the retrospective nature of this study and several variables prevent a meaningful analysis, the overall results still support the feasibility of developing a prospective study of PBSCT with a larger number of children with high-risk neuroblastoma.     

Late-onset lipid peroxidation and neuronal cell death following transient forebrain ischemia in rat brain

The receptor encoded by the W (c-kit) locus is expressed on the membrane of mouse primordial germ cells, whereas its ligand termed stem cell factor (SCF), encoded by the Sl locus, is expressed on the membrane of somatic cells associated with both the primordial germ cell migratory pathways and homing sites. Using an in vitro short time assay which allows a quantitative measure of adhesion between cells, in the present paper we show that SCF/c-kit interaction can modulate primordial germ cell adhesion to somatic cells. We report that the adhesiveness of 11.5 dpc primordial germ cells to four types of somatic cells in culture (TM4 cells, STO fibroblasts, bone marrow stromal cells and gonadal somatic cells) is significantly reduced by antibodies directed against c-kit receptor or SCF, as well by soluble SCF. This SCF/c-kit mediated adhesion seems independent of SCF-induced tyrosine autophosphorylation of c-kit receptor. Moreover, primordial germ cells showed a poor ability to adhere to a bone marrow stromal cell line carrying the Sl(d) mutation (unable to synthesize membrane-bound SCF). This adhesiveness was not further impaired by anti-c-kit antibody. These results demonstrate that SCF/c-kit interaction contributes to the adhesion of primordial germ cells to somatic cells in culture and suggest that the role played by SCF in promoting survival, proliferation and migration of these cells in vitro and in vivo, demonstrated by several studies, might depend on the ability of the membrane-bound form of this cytokine to directly mediate primordial germ cell adhesion to the surrounding somatic cells.     

"Alone, I wouldn''t have known what to do": a qualitative study on social support during labor and delivery in Mexico

Time-related changes in the mean resistance of sartorius muscle from individual common frogs to the toxic effect of chloral hydrate (0.05 and 0.08 M) were observed. The correlation coefficient between the initial muscle resistance and the value and direction of its changes as well as between the resistance of the paired muscle under the influence of subtoxic chloral hydrate solution (0.005 M) was calculated. A biphase pattern of change of almost all the above indices depending on the dose of pretreatment was observed. Time-related changes in the correlation coefficient between muscle resistance and its changes and between the resistance of the paired muscle and variability of the resistance proved to be much more informative than the mean resistance concerning both the muscle response to the stimulus and functional state of the muscle cells.