Functional mapping of the activity of the R region in the human T-cell leukemia virus type I long terminal repeat to increase gene expression

We previously demonstrated the activity of the R fragment in the long terminal repeat of human T-cell leukemia virus type I for elevation of the level of gene expression. In this study, the fragment was deleted with BAL31 nuclease to determine its functional domain. Series of the shortened R fragments were linked to the simian virus 40 promoter unit, which regulated expression of a reporter gene. Examination with the R fragments deleted from the 5 and 3 ends showed that borders of the functional domain were mapped within nucleotide positions 458 to 473 for the 5 end and nucleotide positions 559 to 594 for the 3 end, respectively. Thus we conclude that a 136-base-pair fragment corresponding to the second half of the R region was sufficient to allow elevation of the level of gene expression.     

Subtle translocation (18;21) confirmed by FISH in a patient with Down syndrome

The patient presented with the typical features of Down syndrome: hypotonia, brachycephaly, flattened occiput, bilateral prominent medical epican-thic folds, flat nasal bridge, protruding tongue, low-set dysplastic ears, short broad hands, bilateral clinodactyly and simian crease. The karyotype of this child was originally reported as normal. High-resolution chromosomes revealed extra material on the long arm of chromosome 18. The mother's karyotype showed a reciprocal translocation between the long arm of 18 and the long arm of 21 at band q23 and q22.1, respectively. FISH performed separately with two different 21q cosmid probes gave two signals on the mother's metaphases and three signals on the prob-and. These findings confirmed that the proband is trisomic for the long arm of chromosome 21 at loci D21S65 and D21S19.     

Human placentae membrane receptor for IgG—i. Studies on properties and solubilization of the receptor

Characterization of the human placental membrane receptor for human ¹²⁵I-IgG is described. The receptor bound specifically both monomers and aggregates of human IgG. Human colostral IgA, bovine, sheep, pig, and horse IgG were not bound. No effect of pH in the range 6.6–7.4, ionic strength in the range 0.1–0.5, and temperature between 4 and 45°C on the binding was found. A water-soluble fraction containing the active receptor (glycoprotein fraction-PGP) was obtained from the placental membranes using lithium diiodosalicylate. The solubilized receptor interacted with IgG better at 4°C than at 20°C or 37°C. The results on replacement of monomeric IgG by aggregated IgG, and vice versa, suggest that both monomers and aggregates of human IgG, were bound to the same receptor sites. The apparent association constant for monomeric human IgG was 0.86 ± 0.2 × 10⁷ mole^?1, and 2.0 ± 0.16 × 10¹⁵ IgG molecules were bound per l mg of the membrane protein. Formaldehyde (0.1%), 2-mercaptoethanol (50 mM), and periodate (4 mM) showed no effect on the binding properties of the membrane-bound and on the solubilized receptor, as well. Higher concentrations of periodate (10 mM or 20 mM) decreased the binding of IgG to membranes but showed no effect on the water-soluble receptor. Both the membrane-bound and the solubilized receptor were sensitive to papain. Pronose abolished the receptor activity after prolonged proteolysis only. Neuraminidase did not affect the activity of the receptor. The decrease of the binding activity of the membrane-bound receptor by trypsin and phospholipase C was due to a release of a material containing an active receptor. No effect of trypsin or phospholipase C on the activity of solubilized receptor was observed. The results obtained suggest a protein character of the placental Fc receptor. After electrophoresis of ¹²⁵I-labeled solubilized receptor in polyacrylamide gel in the presence of SDS, 2 major protein peaks with molecular weights of 74,000 and 104,000 and 3 minor peaks with molecular weights of 56,000, 144,000, and 163,000 were found.     

Ribosomal DNA internal transcribed spacer sequences do not support the species status of Ampelomyces quisqualis, a hyperparasite of powdery mildew fungi

Phylogenetic relationships among Ampelomyces isolates, pycnidial hyperparasites and biological control agents of powdery mildews, were inferred from internal transcribed spacer (ITS) sequences of the ribosomal DNA (rDNA). Currently, these hyperparasites are considered to be a single species, A. quisqualis, despite observed morphological and cultural differences. Ten Ampelomyces isolates, representing seven previously defined ITS RFLP groups, were sequenced and analyzed. Sequence-divergence values among isolates belonging to different RFLP groups ranged from 4.3 to 22.4%, suggesting that these isolates may represent different taxa. When Ampelomyces ITS sequences were analyzed by cladistic methods with the sequences of other ascomycetous fungi, they formed two lineages in the Dothideales. Slow-growing Ampelomyces isolates formed a clade with Leptosphaeria microscopica and L. nodorum, whereas fast-growing Ampelomyces isolates formed a clade with Epicoccum nigrum. Sequence-divergence values between these two clades ranged from 17.3 to 22.4%, suggesting that the taxa in the two clades are not closely related and possibly not congeneric. The data presented here indicate that the identification of `A. quisqualis' isolates used in biological control experiments should be re-evaluated. Received: 10 March 1997 / Accepted: 13 February 1998     

Allergic conversion of protective mucosal immunity against nasal bacteria in patients with chronic rhinosinusitis with nasal polyposis

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Comparative study of the prognostic value of nuclear grade and silver-binding nucleolar organizer region in renal cell carcinomas.

Silver-binding nucleolar organizer region (AgNOR) and nuclear grade were histologically assessed in 112 renal cell carcinomas. Nuclear grade was better capable of stratification than AgNOR in terms of survival prediction. It also had prognostic significance when total metastatic rates were evaluated. Although higher mean AgNOR numbers were constantly associated with higher nuclear grades, two arbitrary classifications of AgNOR (less than 1.5, 1.5-3.5, greater than 3.5; less than 2, 2-3, greater than 3) failed to resolve the survival difference.     

Visual and vestibular signals in the lateral mesencephalic tegmental region of the cat

Summary Single unit recordings from two alert cats were used in an attempt to further elucidate the function of the lateral mesencephalic tegmental region (LTR), a part of the mesencephalon forming a link between the superior colliculus and the lower brain stem. A total of 155 units recorded from the LTR were tested with visual, vestibular and acoustic stimuli. Of these, 54 cells (36%) were characterized as either visually (n=33) or vestibularly (n=21) responsive and an additional 13 cells were driven by complex acoustic stimuli. Visually responsive cells typically were directionally selective with large, mainly contralateral receptive fields. Vestibularly responsive cells were modulated by stimulation of either the horizontal canals (yaw stimulation; n = 16) or of both pairs of vertical canals (pitch stimulation; n=5). About half of the cells with activity modulated by rotation about the yaw axis increased discharge during ipsiversive (Type I), the other half during contraversive rotation (Type II). Of the 5 cells with activity modulated by pitch stimulation, 4 preferred the nose-down and only 1 the nose-up direction. Although the discharge of units responsive to yaw stimulation was roughly in phase with head velocity (mean phase lag with respect to head velocity: 10.6 deg), none of the vestibular cells had activity correlated with eye position, eye velocity or movement of visual stimuli. Our observations suggest that the LTR might introduce visual and vestibular signals into the tecto-facial pathway which may be used to adjust the size of pinna movements with respect to the size of ongoing head- or body movements.     

互隔交链孢霉提取物对淋巴细胞核仁形成区及细胞增殖周期的影响

本实验应用人类核仁形成区(NORs)选择性银染方法和细胞光度术,观察了互隔交链孢霉两菌株提取物261-B_2-3和C_(12)b_3-2对人淋巴细胞NORs活性的影响以及后者对细胞增殖周期移行的影响。结果显示,应用不同浓度的261-B_2-3和C_(12)b_3-2提取物处理细胞后,细胞携带Ag-NORs的染色体数明显减少,与对照组比较差异极显著(P<0.01)。表明两株提取物能明显抑制淋巴细胞NORs的活性。细胞暴露于不同浓度的C_(12)b_3-2提取物后,G_1%明显增多,S%和G_2+M%显著减少,与对照相比差异极显著(P<0.01)。说明C_(12)b_3-2提取物可能作用于G_1后期或S早期,延缓和阻滞了细胞周期的移行。     

Chromatin interactions in differentiating keratinocytes reveal novel atopic dermatitis– and psoriasis-associated genes

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