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The Fourth Brazilian Consensus for Autoantibodies Screening in HEp-2 Cells (ANA) was held in Vitória, Espírito Santo, and aimed to discuss strategies and recommendations about the technique, standardization, interpretation and quality control of the indirect immunofluorescence reaction on HEp-2 cells.

Abstract: Chemical separation yield of actinide elements from soil samples containing high amounts of organic matters was often low as compared to that for samples containing low organic matters. We compared chemical yield of uranium and plutonium from organic-rich Japanese soil and humic acid samples which were subjected to three different pretreatment procedures ((1) pulverization only, (2) dry-ashing at 510 °C after pulverization, and (3) 680 kGy gamma-ray irradiation after pulverization) prior to acid digestion. Separation of U and Pu was performed by U-TEVA resin and AG1-X8 anion exchange resin, respectively. For organic samples, pretreatment procedures governed the yield of actinide elements significantly. Chemical separation yield of U was low (6±1%) for Aldrich humic acid sample after dry-ashing at 510 °C. For such samples, gamma-ray irradiation improved the yield of U to 35±22%. Recovery of Pu was lower for some organic soil samples which were dry-ashed at 510 °C (27±2%) as compared to those which were not dry-ashed (62±10%).

The aim of this study was to investigate spatial memory and quantitative acetylcholine transporter autoradiography using a high-sensitivity imaging plate system in rats treated with β-amyloid protein, a model of Alzheimer's disease. An eight-arm radial maze was used to evaluate spatial memory. The performance of the eight-arm radial maze task was impaired in β-amyloid protein-treated rats. In the parietal cortex, 3H-vesamicol binding to the vesicular acetylcholine transporter was significantly lower in β-amyloid protein-treated rats than in vehicle-treated rats, and was significantly correlated with the mean number of correct selections in the maze task of the first 5 days in the post-operative state. These results indicate that the reduction in 3H-vesamicol binding to vesicular acetylcholine transporter is related to memory impairment induced by β-amyloid protein. β-Amyloid protein-infused rats with spatial memory impairment may be useful for the development of new radiolabelled vesamicol analogues for the objective evaluation of Alzheimer's disease.

Objectives To assess the extent of loss of myelinated nerve fibres and spinal motor neuron loss in chronic inflammatory demyelinating polyneuropathy (CIDP), a clinicopathological study was conducted on biopsied sural nerves and necropsied spinal cords from patients with CIDP. Methods The myelinated fibre pathology of 71 biopsied sural nerves and motor neuron pathology of nine necropsied spinal cords at L4 levels in patients with CIDP were quantitatively and immunohistochemically assessed. Results Myelinated nerve fibre density was significantly diminished to 65.4% of the control values (p <0.0001), correlating inversely with the extent of segmental demyelination and remyelination (r = -0.43, p < 0.0005) and duration of illness (r = -0.31, p < 0.01). Numbers of large spinal motor neurons in CIDP were variably but significantly diminished (range from 46.0 to 97.6% of the age matched control value (p < 0.005)), and reactive astrogliosis was evident in the ventral horn in CIDP. The frequency of ventral horn neurons exhibiting central chromatolysis and the accumulation of phosphorylated high molecular weight neurofilament protein was significantly higher in CIDP than in controls (p<0.01 and p<0.05). Conclusions The loss of nerve axons and spinal motor neurons is common in CIDP, and extensive in some cases. These neuronal and axonal losses may influence the functional prognosis in CIDP.

The granulocyte colony‐stimulating factor (G‐CSF) receptor has a composite structure consisting of an immunoglobulin(Ig)‐like domain, a cytokine receptor‐homologous (CRH) domain and three fibronectin type III (FNIII) domains in the extracellular region. Introduction of G‐CSF receptor cDNA into IL‐3‐dependent murine myeloid cell line FDC‐P1 and pro‐B cell line BAF‐B03, which normally do not respond to G‐CSF, enabled them to proliferate in response to G‐CSF. On the other hand, expression of the G‐CSF receptor cDNA in the IL‐2‐dependent T cell line CTLL‐2 did not enable it to grow in response to G‐CSF, although G‐CSF could transiently stimulate DNA synthesis. Mutational analyses of the G‐CSF receptor in FDC‐P1 cells indicated that the N‐terminal half of the CRH domain was essential for the recognition of G‐CSF, but the Ig‐like, FNIII and cytoplasmic domains were not. The CRH domain and a portion of the cytoplasmic domain of about 100 amino acids in length were indispensable for transduction of the G‐CSF‐triggered growth signal.

Summary The ability of T cells to secrete IL-2 in patients with systemic lupus erythematosus (SLE) was investigated. In patients with SLE, impaired IL-2 production by peripheral blood lymphocytes stimulated with mitogens is well known. In this paper, we report that purified T cells stimulated with mitogens, in the presence of Epstein-Barr virus transformed B cells (B-LCL) as an accessory cell, however, could secrete a large quantity of IL-2 as much as normal T cells. In order to study this potential capacity of T cells to secrete IL-2 in patients with SLE, IL-2 secreting T cells were examined. To obtain these cells, T cells were divided into cluster forming cells and noncluster forming cells after short culture of T cells with accessory cells in the presence of Con A. Then the ability of IL-2 production in two kinds of separated T cells was examined. We found that 1) after short culture with B-LCL, the cluster forming T cells could secrete IL-2 when cultured again, but noncluster forming T cells could not, even in the presence of B-LCL, 2) after short culture with macrophages, in normal donors and SLE patients, noncluster forming T cells were able to secrete a greater amount of IL-2 than cluster forming and undivided T cells when cultured with B-LCL. These results suggested that IL-2 secreting T cells activated with Con A in the presence of macrophages were shown to be not all of, but a part of them, and that in SLE T cells which secreted IL-2 in the presence of macrophages might be impaired but other IL-2 secreting T cells might remain intact.

Vascular endothelial growth factor (VEGF) is an endothelial specific angiogenic mitogen secreted from various cell types including tumor cells. Increasing evidence suggests that VEGF is a major regulator of physiological and pathological angiogenesis, and the VEGF/VEGF receptor system has been shown to be necessary for glioma angiogenesis. Hypoxia seems to play a critical role in the induction of VEGF expression during glioma progression. C6 glioma cells provide an in vivo glioma model for the study of tumor angiogenesis, and the expression of VEGF in C6 cells has been shown to be up-regulated by hypoxia in vitro. However, little is known about the molecular mechanism of hypoxic induction of VEGF. Here, we demonstrate that hypoxic induction of VEGF in C6 cells is due to both transcriptional activation and increased stability of mRNA. Nuclear run-on assays revealed a fast and lasting transcriptional activation, whereas the determination of mRNA half-life showed a slower increase of mRNA stability during hypoxia. Reporter gene studies revealed that hypoxia responsive transcription-activating elements were present in the 5'-flanking region of the VEGF gene. These results suggested that several distinct molecular mechanisms were involved in hypoxia-induced gene expression and were activated in a biphasic manner.

The relation between axial forces and their distribution on the pulley for a newly–developed block–type CVT V–belt was studied experimentally. The axial force applied to one block is not constant through the arc of contact even when initial tension only without the transmission power is applied. When the belt is in the pulley, according to the contact progress from the entrance toward the exit, the axial force increases rapidly, and finally it records the highest value at the exit point. From the dynamic test, it was confirmed that this belt has high power transmitting ability notwithstanding its compact form. A modified Ogasawara's equation for predicting the relation between two axial forces was also proposed.

The relation between axial forces and their distribution on the pulley for a newly–developed block–type CVT V–belt was studied experimentally. The axial force applied to one block is not constant through the arc of contact even when initial tension only without the transmission power is applied. When the belt is in the pulley, according to the contact progress from the entrance toward the exit, the axial force increases rapidly, and finally it records the highest value at the exit point. From the dynamic test, it was confirmed that this belt has high power transmitting ability notwithstanding its compact form. A modified Ogasawara's equation for predicting the relation between two axial forces was also proposed.

Summary: Clone MC3T3-E1 cells isolated from newborn mouse calvaria had the same type of alkaline phosphatase (ALP) as that found in adult mouse calvaria (the liver-bone-kidney type), as judged by polyacrylamide gel electrophoresis as well as by heat lability and amino acid inactivation. The effects of prostaglandin E2 (PGE2), parathyroid hormone (PTH), 1,25 dihydroxycholecalciferol [1,25(OH)2D3], and adenosine-3′, 5′-cyclic monophosphate (cAMP) analogs on ALP were investigated. PGE2 and 1,25(OH)2D3 increased ALP activity in dose-related manner with a maximal effect at concentrations of 10 ng/ml and 40 pg/ml, respectively. N6,O2-dibutyryl adenosine-3′, 5′-cyclic monophosphate (DBcAMP) also induced an increase in ALP activity in a dose-related fashion with a maximal effect at a concentration of 0.5 mM which was 2.2-fold over that of the controls. Induced ALP was of the “liver-bone-kidney” type. Antinomycin D and cycloheximide inhibited the increase in ALP activity induced by DBcAMP. The level of ALP was elevated by 8-bromo-adenosine-3′,5′-cyclic monophosphate and theophylline, but not by N6,O2-dibutyryl guanosine-3′,5′-cyclic monophosphate and sodium butyrate. Moreover, PGE2 dramatically increased the level of cAMP in the cells with a maximal effect at a concentration of 10 ng/ml, indicating that PGE2 and DBcAMP induce an increase of ALP activity in clone MC3T3-E1 cells by increasing the cAMP level; PTH did not affect enzyme activity and cAMP, level in the cells. These results suggest that PGE2, DBcAMP, and 1,25(OH)2D3 are involved in bone formationin vivo as well.

BACKGROUND & AIMS: Germline mutations of DNA mismatch repair genes are responsible for cancer susceptibility in hereditary nonpolyposis colorectal cancer (HNPCC) kindreds. Transforming growth factor beta type II receptor (TGF-beta RII) has been found to be somatically altered in HNPCC. The aim of this study was to clarify further the role of TGF-beta RII alterations in HNPCC tumorigenesis, particularly in adenomas. METHODS: Fourteen adenoma specimens and 13 cancer specimens from 10 patients with HNPCC were screened for mutations in the short repeated sequences of the TGF-beta RII gene by polymerase chain reaction-single-strand conformation polymorphism. Mismatch repair genes, replication errors, and c-K-ras 2 were also analyzed in HNPCC tumors. RESULTS: Alterations of the TGF-beta RII gene at the short poly(A) repeat were found in 8 (57%) adenoma specimens and 11 (85%) cancer specimens. They were found at an earlier stage of adenomas. Two adenoma specimens showed two-hit inactivation of mismatch repair genes. Replication errors were detectable in 13 (93%) adenoma specimens. Mutations in c-K-ras 2 codon 12 were detected at a 50% frequency in adenoma specimens. CONCLUSIONS: These data indicate a strong association between TGF-beta RII gene alterations and adenoma-carcinoma progression in HNPCC. (Gastroenterology 1997 Jan;112(1):33-9)

Yeast Yge1p, the gene product of YGE1, is a eukaryotic GrpE homolog found recently (Ikeda et al., 1994). We have revealed here that Yge1p is a soluble protein in the mitochondrial matrix. Depletion of Yge1p in yeast cells resulted in accumulation of the precursor of F1-ATPase β subunit in vivo, suggesting that Yge1p is involved in protein import into mitochondria. Overexpression of Yge1p in the temperature-sensitive mutant strains of mitochondrial hsp70, Ssc1p, caused hypersensitivity to temperature for cell growth, suggesting a genetic interaction between the YGE1and SSC1genes. A physical interaction between Yge1p and Ssc1p was directly demonstrated by co-immunoprecipitation of Ssc1p by the anti-Yge1p antibodies. We propose that Yge1p functions in cooperation with Ssc1p in a similar manner as bacterial GrpE with DnaK.

The pyrolysis kinetics of acetonitrile dilute in argon has been studied in the temperature range 1400−2100 K at an average pressure of 12 atm in single-pulse shock tube experiments. The principal products are HCN, C2H2, CH4, and H2, while the minor products include HCCCN, H2CCHCN, C2H4, and C4H2. The overall kinetics is successfully simulated by an 87 step kinetic model that accurately accounts for the temperature profiles of the major products and also provides an acceptable fit for the minor products. The thermochemistry and rate parameters of a number of key reactions have been obtained by ab initio quantum chemical calculations carried out at CASSCF, CASPT2, and Gaussian-2 levels of theory. Several distinct reaction pathways were studied, whereby the geometries, vibrational frequencies, and energies of approximately 70 molecular species representing reactants, products, intermediates, and transition states were computed. The pyrolysis of acetonitrile is initiated by CH bond fission, forming a cyanomethyl radical. This reaction is the most sensitive one in the kinetic model. On the basis of sensitivity analyses of the model as well as ab initio calculations, the heat of formation of cyanomethyl has been revised as %@mt;sys@%Δ%@sb@%f%@sbx@%%@mh;1.5q@%%@ital@%H%@rsf@%%@mh;1.5q@%%@sx@%298%@be@%0%@sxx@%%@mx@% (CH2CN) = 263 ± 9 kJ mol^-1. The limiting high-pressure value of the corresponding rate constant, as obtained by ab initio variational transition state calculations, is k1∞ = 1.2 × 10¹⁶ exp(−413 kJ mol^-1/RT) s^-1, which is in good agreement with our extrapolated experimental measurement. A number of the observed products, including HCCCN and H2CCHCN, largely arise from the decomposition of succinonitrile, a key intermediate, that forms by the recombination of two cyanomethyl radicals.

The granulocyte colony-stimulating factor receptor (G-CSF-R) and growth hormone receptor (GH-R) belong to the cytokine receptor family and have some similarity in the cytokine receptor-homologous (CRH) domain of the extracellular region. Among members of this family, the G-CSF-R and GH-R seem to function as homodimers. Previously, we showed that mouse myeloid precursor FDC-P1 cells expressing the G-CSF-R can respond to G-CSF for growth. Here we show that the GH-R can also transduce the growth signal in FDC-P1 cells in the range 10 pM-100 nM GH. At a higher concentration of GH, GH did not promote the growth of the transformant cells. A series of chimeric receptor cDNAs between the G-CSF-R and GH-R cDNAs was constructed by exon swapping and was expressed in FDC-P1 cells. A ligand-binding assay with transformants expressing chimeric receptors indicated that the entire CRH domain is necessary for specific binding of the ligand. Although the transmembrane and cytoplasmic regions of the G-CSF-R and GH-R have no apparent similarity, these regions were interchangeable, resulting in growth-signal transduction in FDC-P1 cells.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.