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     

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.     

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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High TT virus load as an independent factor associated with the occurrence of hepatocellular carcinoma among patients with hepatitis C virus-related chronic liver disease

The TT virus (TTV) load was estimated in sera obtained from 237 patients with hepatitis C virus (HCV)-related chronic liver disease including 42 patients with hepatocellular carcinoma (HCC), by real-time detection PCR using primers and a probe derived from the well-conserved untranslated region of the TTV genome, which can detect all known TTV genotypes. Of the 237 patients studied, 18 (8%) were negative for TTV DNA, 87 (37%) had low TTV viremia (1.3 x 10(2)-9.9 x 10(3) copies/ml), and 132 (56%) had high TTV viremia (1.0 x 10(4)-2.1 x 10(6) copies/ml). Various features were compared between the patients with high TTV load (n = 132) and those with no TTV viremia or low viral load (n = 105). High TTV viremia (> or =10(4) copies/ml) was significantly associated with higher age (P < 0.05), past history of blood transfusion (P < 0.001), complication of cirrhosis (P < 0.05) or HCC (P < 0.0005), lower HCV RNA titer (P < 0.05), and lower platelet count (P < 0.01). On multivariate logistic regression analysis, high TTV viral load was a significant risk factor for HCC (P < 0.05), independent from known risk factors such as complication of liver cirrhosis (P < 0.0001) and high age (> or =65 years, P < 0.05), among all 237 patients. Furthermore, high TTV viral load was an independent risk factor for HCC among the 90 cirrhotic patients (P < 0.05). These results suggest that a high TTV viral load is associated independently with the complication of HCC and may have prognostic significance in patients with HCV-related chronic liver disease, although whether high TTV viremia mediates the progression of HCV-related chronic liver disease remains to be defined.     

Arterial supply of the temporo-medial region of the brain significance for preoperative vascular occlusion testing

The mesiobasal limbic system is of particular significance in the surgical treatment of temporo-medial tumors and epilepsy. It consists of the uncus, amygdaloid body, hippocampus, dentate gyrus, subiculum, fasciolar gyrus and the parahippocampal gyrus. Knowledge of the vascular microanatomy is a key to the surgical treatment of pathologies in the region. The anterior choroidal artery was selectively injected in fresh brain specimens 50 specimens with a gelatinous ink mixture to demonstrate vascular territories in stereotactic brain slices, and 50 with a Biodur resin to obtain casts for microanatomical evaluation. The cast technique was also applied to 35 specimens injected into the posterior cerebral artery. The rostral third of the temporomedial region is mainly supplied by branches of the anterior choroidal artery. The occipital two thirds are supplied by hippocampal branches, the posteromedial choroidal artery and the inferior temporal branches of the posterior cerebral artery. Important vessel variations with significant implications for the preoperative Wada-test are presented     

Mitochondrial DNA polymorphisms in Yunnan nationalities in China

Nucleotide sequences of the D-loop region of human mitochondrial DNA from four Yunnan nationalities, Dai, Wa, Lahu, and Tibetan, were analyzed. Based on a comparison of 563-bp sequences in 99 people, 66 different sequence types were observed. Of these, 64 were unique to their respective populations, whereas only 2 types were shared between the Lahu and Wa nationalities. The D-loop sequence variation and phylogenetic analysis suggested that the 99 mtDNA lineages were classified into eight clusters in the phylogenetic tree. All lineages that had a 9-bp deletion in the COII/tRNA^Lys intergenic region appeared in one cluster in the D-loop tree, suggesting a single event of the deletion in the Yunnan nationalities studied. Genetic distances, based on net nucleotide diversities between populations including Han Chinese and mainland Japanese, revealed that the Dai, Wa, Lahu, and Han Chinese are closely related to each other, while Tibetan and mainland Japanese formed a single cluster. The bootstrap probabil-ity of separation between the Dai-Wa-Lahu-Chinese clade and the Tibetan-Japanese clade was 99%, indicating that there are at least two different origins among minority groups in Yunnan province. Although the genetic distance between Tibetan and Japanese within the clade is rather long, the results may shed light on the origins of mainland Japanese. Received: December 22, 2000 / Accepted: January 18, 2001