Microcalorimetric assay on the antimicrobial property of five hydroxyanthraquinone derivatives in rhubarb (Rheum palmatum L.) to Bifidobacterium adolescentis

It was found that the intestinal bacteria balance would be deteriorated by rhubarb especially in long term treatment. Bifidobacteria is one of the most common species of probiotics in human intestine. The suppression of this particular probiotic, such as Bifidobacterium adolescentis, one of the dominant anaerobes in the intestines of humans, might lead to imbalance of intestinal flora and is considered to be potentially riskful for human health. Hence, the inhibitory effects of the five main components of hydroxyanthraquinones (HAQs) contained in rhubarb on B. adolescentis growth were investigated by microcalorimetry to discover the suppression potential of rhubarb and the structure-function relationship of such HAQs. The value of the maximum power- output (P(max)) and slope (k) of the thermogenic growth curves of B. adolescentis were found of decrease in the presence of the five HAQs, while the peak time (T(p)) of the thermogenic curves were found to be delayed. The sequence of antimicrobial activity of the five HAQs is rhein>emodin>aloe-emodin>chrysophanol>physicion. The functional groups carboxyl, hydroxyl and hydroxylmethyl on phenyl ring in HAQs could improve the antimicrobial activity. The influence of substituent groups on anti- B. adolescentis activity might be related with the polarity and the sequence was carboxyl>hydroxyl>hydroxylmethyl>methyl and methoxyl.

Depression, anxiety and quality of life in parents of children with epilepsy

OBJECTIVES

To assess the impact of childhood epilepsy on parental quality of life (QOL) and psychological health, and to investigate possible correlations between parental QOL and background variables as well as parental anxiety and depression.

SUBJECTS AND METHODS

Parents having an epileptic child (n = 263) and parents having a healthy child (n = 270) were enrolled. Groups were in balance for background variables. Short-Form Health Survey (SF-36) Questionnaire, Zung Depression Scale (ZDS) and Zung Anxiety Scale (ZAS) were applied to all parents. Patients were divided into the first visit group (newly diagnosed epilepsy) and follow-up visit group.

RESULTS

The parents of children with epilepsy had significantly lower QOL scores in SF-36 for all subscales and higher levels of depression and anxiety by using ZDS and ZAS. The factors correlated with parental QOL were seizure control, visit status, anxiety, depression, employment, cost of epilepsy, status epilepticus, drug side effect and age of parents.

CONCLUSIONS

Childhood epilepsy has a severe impact on parental QOL and psychological health, and recognition of possible correlations between parental QOL and background variables will be helpful to improve parental QOL.

Role of FOXC1 in regulation of basal-like/triple-negative breast cancer

11016

Background: Class identification studies have proposed 3 prognostically relevant molecular subtypes of breast cancer: luminal, HER2 and basal-like. The latter is associated with poor prognosis but its molecular basis is not clear. We hypothesized a direct correlation between FOXC1 expression and basal-like breast cancer. Methods: Expression of FOXC1, CK5, CK14, EGFR, c-Kit, αB-crystallin, ITGB4 and FOXC2 in basal-like breast cancer was examined using publicly available microarray datasets. A molecular signature of 40 genes sharing co-ordinate up or down regulation with FOXC1 was identified on one microarray (49 patients) and validated on 5 other microarrays (1,232 patients). The clinical significance of FOXC1 gene expression and the FOXC1 gene signature was evaluated using censored survival data. FOXC1 protein expression was assessed by immunohistochemistry (IHC) of a 96-sample breast cancer tissue microarray. Normal breast epithelial, luminal and basal breast cancer cells transfected with FOXC1 vectors were evaluated for cell proliferation, migration and invasion. Results: FOXC1 was found to be consistently and exclusively upregulated in basal-like triple negative breast cancer and was associated with poor overall survival (p<0.0001). The FOXC1 gene signature accurately predicted the basal-like phenotype. IHC analysis of FOXC1 protein expression in human breast cancers confirmed its potential to be used as a clinical biomarker of basal-like breast cancer. Normal breast epithelial cells and luminal breast cancer cells with low or no FOXC1 expression underwent epithelial-to-mesenchymal transition and displayed increased cellular proliferation, migration, invasion, and expression of basal cell markers when FOXC1 was overexpressed. In contrast, knockdown of FOXC1 by shRNA in basal-like breast cancer cells conferred luminal phenotype. Breast cancer progression-linked signaling pathways like NF-κB and p38MAPK were significantly stimulated in basal-like breast cancer as well as by in vitro FOXC1 overexpression. Conclusions: FOXC1 is a dominant determinant of the basal-like phenotype of breast cancer. We propose FOXC1 to be the single best molecular marker of and a potential therapeutic target for basal-like / triple negative breast cancer.

No significant financial relationships to disclose.

Effects of DNAzymes targeting Aurora kinase A on the growth of human prostate cancer

Aurora kinase A has been demonstrated to be involved in the malignant progression of many types of cancer including prostate cancer, we therefore hypothesized that Aurora kinase A might work as a valuable target for prostate cancer treatment. To test this hypothesis, we used DNAzyme technology to inhibit Aurora kinase A expression and evaluated the effects of DNAzymes as therapeutic agents to treat prostate cancer. In an in vitro cleavage assay, we found that a DNAzyme (DZ2) targeting Aurora kinase A could effectively cleave Aurora kinase A mRNA. When transfected into the prostate cancer cell line PC3, DZ2 was found to strongly inhibit the expression of Aurora kinase A examined by western blot analysis, and thus suppressed cell growth, arrested the progression of cell cycle, induced cell apoptosis and attenuated cell migration, as measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay, flow cytometry and Boyden chamber assay. Through in vivo study, we also found that DZ2 could significantly inhibit the growth of human prostate cancer xenografts in nude mice. In conclusion, DZ2 could effectively attenuate malignant progression of prostate cancer both in vitro and in vivo, suggesting that DNAzyme targeting Aurora kinase A may be used as a valuable therapy to treat prostate cancer.

Protein kinase C activation inhibits alpha1D L-type Ca channel: a single-channel analysis

The recently reported alpha1D Ca channel in the heart is known to be regulated by protein kinase C (PKC) at the whole cell level and has been implicated in atrial fibrillation. The biophysical basis of this regulation at the single-channel level is not known. Therefore, the effect of PKC activation was studied on alpha1D Ca channel expressed in tsA201 cells using cell-attached configuration. Unitary currents were recorded in the presence of 70 mM Ba2+ as the charge carrier at room temperature. Under basal condition, channel activity was rare and infrequent; however, Bay K 8644 (1 microM) induced channel openings with a conductance of 22.3 pS. Single channel analysis of open and closed time distributions were best fitted with a single exponential. PKC activation by 4alpha-phorbol 12-myristate 13-acetate (PMA; 10 nM), a phorbol ester derivative, resulted in a decrease in open probability and increase in closed-time without any significant effect on the conductance of the alpha1D Ca channel. This is consistent with a decreased entry of alpha1D Ca channel into open states in the presence of PMA. PMA effects could not be reproduced by 4-alpha Phorbol, an inactive PMA analogue. These data show, for the first time, (1) the alpha1D Ca channel activity at the single-channel level and (2) the biophysical basis by which PKC activation inhibits the alpha1D Ca channel. The shortening of the open-time and the lengthening of the closed-time constants and the increase in blank sweeps may explain the inhibition of the previously reported whole-cell alpha1D Ca current. Altogether, these data are essential for understanding the complex role of alpha1D Ca channel not only in physiological settings but also in pathological settings such as atrial fibrillation.

Isolation and characterization of a Lactobacillus fermentum temperate bacteriophage from Chinese yogurt

AIMS

The aim of this study was to investigate the properties of temperate bacteriophage of Lactobacillus fermentum, based on its morphology, restriction patterns, protein profile and the impact on the growth of host strain.

METHODS AND RESULTS

With Mitomycin C, seven temperate phages were induced from Lactobacilli derived from Chinese yogurt. The temperate phages induced belong to the most common Bradley's group B, having hexagonal head and long, noncontractile tail. They were furthermore confirmed to be the same bacteriophage by identical restriction patterns. SDS-PAGE profile showed that the phage studied had one major structure protein about 31.9 kDa. The presence of the prophage influenced the cell shape and colony size of its lysogenic strain.

CONCLUSIONS

The phage obtained had similar, but not complete identical properties with other L. fermentum phages reported. It influenced the growth behaviour of its lysogenic strain.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides some information about bacteriophages occurring in the Chinese yoghurt manufacture and contributes to our knowledge on the bacteriophage diversity in the dairy industry.

Structure determination of a new protein from backbone-centered NMR data and NMR-assisted structure prediction

Targeting of proteins for structure determination in structural genomic programs often includes the use of threading and fold recognition methods to exclude proteins belonging to well-populated fold families, but such methods can still fail to recognize preexisting folds. The authors illustrate here a method in which limited amounts of structural data are used to improve an initial homology search and the data are subsequently used to produce a structure by data-constrained refinement of an identified structural template. The data used are primarily NMR-based residual dipolar couplings, but they also include additional chemical shift and backbone-nuclear Overhauser effect data. Using this methodology, a backbone structure was efficiently produced for a 10 kDa protein (PF1455) from Pyrococcus furiosus. Its relationship to existing structures and its probable function are discussed.

Coagulase-negative staphylococci in very-low-birth-weight infants: inability of genetic markers to distinguish invasive strains from blood culture contaminants

Selected coagulase-negative staphylococci from the blood of very-low-birth-weight infants in the Neonatal Intensive Care Unit at the Royal Women's Hospital, Melbourne, collected over a 5-year period were examined. Isolates were classified as invasive or contaminants, speciated, typed by pulsed-field gel electrophoresis, and examined for biofilm genes (icaA, icaC, and icaD), adhesion genes (atlE, fbe), and the number of copies of IS256. Of the 24 isolates studied, there were 13 contaminants and 11 invasive isolates. The collection included 15 Staphylococcus epidermidis, eight Staphylococcus capitis, and one each of Staphylococcus warneri and Staphylococcus haemolyticus. Two small clusters of S. epidermidis that belonged to the same molecular type were identified. All S. capitis isolates belonged to the same molecular type or subtype, suggesting that a particular clone was circulating in the unit. There was no significant difference in the species found, the presence of icaA, icaC, icaD, atlE, or fbe, or the number of copies of IS256 between invasive isolates and contaminants. A series of nasal isolates from nonhospitalized adults differed from hospital isolates in the absence of IS256 and the low prevalence of icaC. There was no evidence of IS256-mediated insertion into ica genes as a mechanism of phase variation. These findings suggest that contaminants and invasive isolates derived from the same pool of hospital strains capable of causing sepsis in compromised hosts and that other mechanisms of phase variation exist, apart from IS256 insertion into ica genes.

Preparation of bioactive nanotitania ceramics with biomechanical compatibility

In this article, bioactive nanotitania ceramics with biomechanical compatibility was prepared by using an additive of hydroxyapatite or MgO as particle growth inhibitor. After sintering at 1000 degrees C, the particle size of nanotitania ceramics prepared by using HA as additive (HT) was much smaller than that prepared by using MgO as additive (MT). In simulated body fluid (SBF), HT could induce apatite formation in 4 days, while no apatite could be found on MT even after it was soaked in SBF for 14 days. After Ros17/28 osteoblasts were cultured on the materials for 1, 4, and 6 days, MTT results showed that the osteoblasts on the HT differentiated faster than that on the MT. Mechanical tests results showed that the bending and compressive strength of HT were 160 and 200 MPa, while those of MT were 70 and 88 MPa, respectively. These results demonstrated that it is suitable to prepare bioactive nanotitania ceramics, with biomechanical compatibility, by using HA as particle growth inhibitor.

X-ray microbeams: Tumor therapy and central nervous system research

Irradiation with parallel arrays of thin, planar slices of X-ray beams (microplanar beams, or microbeams) spares normal tissue, including the central nervous system (CNS), and preferentially damages tumors. The effects are mediated, at least in part, by the tissue's microvasculature that seems to effectively repair itself in normal tissue but fails to do so in tumors. Consequently, the therapeutic index of single-fraction unidirectional microbeam irradiations has been shown to be larger than that of single-fraction unidirectional unsegmented beams in treating the intracranial rat 9L gliosarcoma tumor model (9LGS) and the subcutaneous murine mammary carcinoma EMT-6. This paper presents results demonstrating that individual microbeams, or arrays of parallel ones, can also be used for targeted, selective cell ablation in the CNS, and also to induce demyelination. The results highlight the value of the method as a powerful tool for studying the CNS through selective cell ablation, besides its potential as a treatment modality in clinical oncology.

Protein fold recognition through application of residual dipolar coupling data

Residual dipolar coupling (RDC) represents one of the most exciting emerging NMR techniques for studying protein structures. However, solving a protein structure using RDC data alone is a highly challenging problem as it often requires that the starting structure model be close to the actual structure of a protein, for the structure calculation procedure to be effective. We report in this paper a computer program, RDC-PROSPECT, for identification of a structural homolog or analog of a target protein in PDB, which best matches the 15N-1H RDC data of the protein recorded in a single ordering medium. The identified structural homolog/analog can then be used as a starting model for RDC-based structure calculation. Since RDC-PROSPECT uses only RDC data and predicted secondary structure information, its performance is virtually independent of sequence similarity between a target protein and its structural homolog/analog, making it applicable to protein targets out of the scope of current protein threading techniques. We have tested RDC-PROSPECT on all 15N-1H RDC data (representing 33 proteins) available in the BMRB database and the literature. The program correctly identified the structural folds for approximately 80% of the target proteins, significantly better than previously reported results, and achieved an average alignment accuracy of 97.9% residues within 4-residue shift. Through a careful algorithmic design, RDC-PROSPECT is at least one order of magnitude faster than previously reported algorithms for principal alignment frame search, making our algorithm fast enough for large-scale applications.

Crystal structure of trans-diaqua-bis(salicylaldehydato-O,O′) chromium(III) chloride, [Cr(C7H5O2)2(H2O)2]Cl

C14H14ClCrO6, monoclinic, P121/c1 (No. 14), a = 8.998(18) Å, b = 18.68(4) Å, c = 4.945(10) Å, β = 105.95(2)°, V = 799.2 Å3, Z = 2, Rgt(F) = 0.069, wRref(F2) = 0.170, T = 298 K.

Neurons derived from embryonic stem (ES) cells resemble normal neurons in their vulnerability to excitotoxic death

We determined whether embryonic stem (ES) cells could provide a model system for examining neuronal death mediated by glutamate receptors. Although limited evidence indicates that normal neurons can be derived from mouse ES cells, there have been no studies examining pathophysiological responses in mouse ES cell systems. Mouse ES cells, induced down a neural lineage by retinoic acid (RA), were found to have enhanced long-term survival when plated onto a layer of cultured mouse cortical glial cells. In these conditions, the ES cells differentiated into neural cells that appeared normal morphologically and displayed normal features of immunoreactivity when tested for neuron-specific elements. Varying the culture medium generated cultures of mixed neuronal/glial cells or enriched in oligodendrocytes. These cultures were viable for at least four weeks. Real-time PCR analysis of N-methyl-D-aspartate (NMDA) receptor subunits revealed an appropriate age-in-vitro dependent pattern of expression. Neurons derived from ES cells were vulnerable to death induced by a 24-h exposure to the selective glutamate receptor agonists NMDA, kainate, and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA). This vulnerability to agonist-induced death increased with age in vitro, and related closely to expression of receptor subunits, as it does in cultured primary neurons. Experiments with selective receptor antagonists showed that glutamate receptors mediated the NMDA- and kainate-induced death. Neuronal differentiated ES cells therefore exhibited an excitotoxic response resembling that displayed by central nervous system (CNS) neurons. Thus, ES cells, which are very amenable to genetic manipulation, provide a valid system for studying glutamate receptor-mediated toxicity at the molecular level.

Reorganization in the visual cortex after retinal and cortical damage

Retinal and cortical lesions are completely different events that trigger visual cortical plasticity. We therefore compared the cortical effects of homonymous lesions of the central retina with effects of cortical lesions. All in vivo experiments were performed in anaesthetized, adult cats. Retinal lesions were made with a Xenon-light photocoagulator, and cortical lesions were induced by focal application of heat or ibotenic acid injection. Both, in cortical regions representing the retinal scotoma and at the border of small focal cortical lesions single neuron activity was initially suppressed and accompanied by a narrow area of increased activity adjacent to the region of functional loss during the first 1-2 weeks. At the same time an increased glutamatergic NMDA response and a reduction of GABA(A) and GABA(B) responses was observed around the cortical lesions in vitro. At an early stage long-term potentiation (LTP) is facilitated in those regions that were characterized by local upregulation of excitation and downregulation of inhibition after cortical lesions. Similarly, at the border of cortical scotomas in area 17 an increased glutamate level was found while inside the scotoma GAD levels were reduced. Shifts in topography of retinal representation as well as increases of receptive field size were detected as signs of lesion-induced neuronal reorganization after retinal and cortical lesions with longer survival times. A common cascade of events is triggered in the visual cortex by retinal as well as cortical lesions: reduced GABAergic inhibition and increased glutamatergic excitation, leading to increased spontaneous activity and visual excitability that is accompanied by facilitated LTP, and appears to initiate local cortical reorganization after functional disturbances in the visual system.

[Inhibition of telomerase activity by ribozyme targeted to human telomerase transcriptase]

Human telomerase reverse transcriptase (hTERT) is the catalytic subunit and the key factor which controls the telomerase activity,so it is the best choice to inhibit telomerase through controling hTERT expression.In this work,a hammer head ribozyme directed against the hTERT mRNA (hTERTRZ) was designed and synthesized to serve as a telomerase inhibitor. In order to test its in vitro cleavage activity, two in vitro transcription plasmids containing hTERTRZ and hTERT gene respectively were constructed. Ribozyme RNA and DIG-labeled-hTERT were synthesized by in vitro transcription. In vitro cleavage reactions were carried out by mixing the hTERTRZ with DIG-labeled-hTERT under different reaction conditions, and cleavage bands were detected by digoxin chemiluminescent assay. hTERTRZ showed a specific cleavage activity against the hTERT used as template. To investigate its in vivo effect of telomerase inhibition in tumor cells, a eukaryotic expression plasmid containing the hTERT ribozyme gene was introduced into HeLa cells and hepatoma cells by using LipofectAMINE. In the transfectants, the level of intact hTERT mRNA and the telomerase activity were clearly reduced, and the telomere length of these clones was apparently shortened at the beginning period, then kept a fixed value without further shortening. All the transfectants with ribozyme grew clearly more slowly than the parental cell line. The doubling time of the tansfectants prolonged compared to the negative control, but no apparent apoptosis was shown even at their 37th passage. These findings suggest the potential application of this ribozyme as a new theraputic agent directed against immortalized cancer cells.

Novel approaches to polynuclear platinum pro-drugs. Selective release of cytotoxic platinum-spermidine species through hydrolytic cleavage of carbamates

BBR3464 is a novel trinuclear platinum drug currently in Phase II clinical trials. Polyamine-bridged dinuclear platinum compounds as represented by [[trans-Pt(NH(3))(2)Cl](2)-mu-spermidine-N(1),N(8)]Cl(3) (1) are highly interesting second-generation analogues of BBR3464 because the hydrogen-bonding and electrostatic contributions of the central platinum-amine group in BBR3464 are replicated by the free, noncoordinated "central" quaternary nitrogens of the linear polyamine linker while the presence of two separate Pt-Cl bonds maintains the bifunctional binding mode on the DNA adducts. Preclinical investigations confirm the potency of these species with cytotoxicity in the nanomolar range. This remarkable potency results in a relatively narrow therapeutic index. To enhance the therapeutic index of these drugs, we investigated the potential for "pro-drug" delivery of less toxic and better tolerated derivatives such as the compounds [[trans-Pt(NH(3))(2)Cl](2)-mu-N(4)-R-spermidine-N(1),N(8)]Cl(2) where N(4)-R represents BOC (tert-butyl), CBz (benzyl), and Fmoc (fluorenylmethyl) carbamate blocking groups, 2-4, respectively. The bulky Fmoc derivative showed evidence for conformational isomers by (1)H NMR spectroscopy due to the inequivalence of the two n-propyl and n-butyl side chains of the spermidine moiety. The rate constants for hydrolysis and release of 1 were calculated. Release of cytotoxic 1 at physiologically relevant pH followed the order 4 > 2 > 3. The calculated values for 4 (pH 5, 6.0(+/-3.9) x 10(-10) s(-1); pH 6, 6.5(+/-0.2) x 10(-9) s(-1); pH 7, 6.0(+/-0.2) x 10(-8) s(-1); pH 8, 1.6(+/-0.1) x 10(-7) s(-1)) show a more pronounced pH dependence compared to 2 (pH 5, 4.6(+/-0.1) x 10(-8) s(-1); pH 6, 4.2(+/-0.1) x 10(-8) s(-1); pH 7, 3.2(+/-0.1) x 10(-8) s(-1)). Preliminary biological assays of cellular uptake and cytotoxicity confirm the utility of the pro-drug concept. While blocked-polyamine compounds such as 2-4 are, in general, 2-3 orders of magnitude less cytotoxic than 1, there is significant cell type variability. Specifically, the Fmoc derivative 4 showed significantly enhanced cytotoxicity warranting further study of the pro-drug concept for greater selectivity and/or oral delivery.

Gene expression of SERCA2a and L- and T-type Ca channels during human heart development

In this study we report, for the first time, on the gene expression of human cardiac SERCA2a, L-type (alpha(1C)) and T-type (alpha(1H)) Ca channels during development, using RNase protection assay, relative quantitative RT-PCR and Western blot. Human hearts during early gestation (8- to 20-wk gestation), neonatal (1- to 4-d-old) and adult (18- to 48-year-old) stages were used. The results show that T-type Ca channel alpha(1H) subunit mRNA decreased and that L-type Ca channel alpha(1C) subunit mRNA increased with development. While the levels of sarcoplasmic reticulum ATPase (SERCA2a) mRNA did not significantly change with development, its protein levels increased with development. In conclusion, SERCA2a, L-type and T-type Ca channel transcripts were detected as early as 8-wk gestation. Defining the profile of Ca handling proteins during development is important to the understanding of excitation-contraction (EC)-coupling of the developing human heart.

Evidence for functional role of epsilonPKC isozyme in the regulation of cardiac Na(+) channels

Investigation of the role of individual protein kinase C (PKC) isozymes in the regulation of Na(+) channels has been largely limited by the lack of isozyme-selective modulators. Here we used a novel peptide-specific activator (epsilonV1-7) of epsilonPKC and other peptide isozyme-specific inhibitors in addition to the general PKC activator phorbol 12-myristate 13-acetate (PMA) to dissect the role of individual PKCs in the regulation of the human cardiac Na(+) channel hH1, heterologously expressed in Xenopus oocytes. Peptides were injected individually or in combination into the oocyte. Whole cell Na(+) current (I(Na)) was recorded using two-electrode voltage clamp. epsilonV1-7 (100 nM) and PMA (100 nM) inhibited I(Na) by 31 +/- 5% and 44 +/- 8% (at -20 mV), respectively. These effects were not seen with the scrambled peptide for epsilonV1-7 (100 nM) or the PMA analog 4alpha-phorbol 12,13-didecanoate (100 nM). However, epsilonV1-7- and PMA-induced I(Na) inhibition was abolished by epsilonV1-2, a peptide-specific antagonist of epsilonPKC. Furthermore, PMA-induced I(Na) inhibition was not altered by 100 nM peptide-specific inhibitors for alpha-, beta-, delta-, or etaPKC. PMA and epsilonV1-7 induced translocation of epsilonPKC from soluble to particulate fraction in Xenopus oocytes. This translocation was antagonized by epsilonV1-2. In native rat ventricular myocytes, PMA and epsilonV1-7 also inhibited I(Na); this inhibition was antagonized by epsilonV1-2. In conclusion, the results provide evidence for selective regulation of cardiac Na(+) channels by epsilonPKC isozyme.

Differential modulation of sodium channel gating and persistent sodium currents by the beta1, beta2, and beta3 subunits

Brain sodium channels are complexes of a pore-forming alpha subunit with auxiliary beta subunits, which are transmembrane proteins that modulate alpha subunit function. The newly cloned beta3 subunit is shown to be expressed broadly in neurons in the central and peripheral nervous systems, but not in glia and most nonneuronal cells. Beta1, beta2, and beta3 subunits are coexpressed in many neuronal cell types, but are differentially expressed in ventromedial nucleus of the thalamus, brain stem nuclei, cerebellar Purkinje cells, and dorsal root ganglion cells. Coexpression of beta1, beta2, and beta3 subunits with Na(v)1.2a alpha subunits in the tsA-201 subclone of HEK293 cells shifts sodium channel activation and inactivation to more positive membrane potentials. However, beta3 is unique in causing increased persistent sodium currents. Because persistent sodium currents are thought to amplify summation of synaptic inputs, expression of this subunit would increase the excitability of specific groups of neurons to all of their inputs.

[Effect of 3'-UTR of EG I from Trichoderma reesei on its gene expression in Saccharomyces cerevisiae]

Several industrial yeast are developed as ideal expression hosts for the production of the commercially useful proteins. The expression levels in yeast cells of the heterologous proteins are affected by the regulation factors of the genes themselves. The full-length cDNA coding for EG I from Trichoderma reesei, the cellulose-degrading filamentous fungus, was expressed in Saccharomyces cerevisiae H158. EG I produced by the recombinant S. cerevisiae exhibits maximal activity at 50 degrees C-60 degrees C, pH 5.0. It was observed that removal of the 3'-untranslated region (3'-UTR) from EG I cDNA resulted in no active EG I produced by recombinant yeast. RT-PCR analysis indicated that unlike the yeast cells harboring full-length EG I cDNA, there was no detectable EG I mRNA in the yeast cells harboring EG I cDNA without 3'-UTR. The data suggested that 3'-UTR is important for the expression of EG I in Saccharomyces cerevisiae.

The cAMP-mediated protein kinase signal transduction pathway is involved in the pyrogenic effect of CRH in rats

OBJECTIVE

To determine whether the cyclic adenosine monophosphate (cAMP) mediated protein kinase signal transduction pathway is involved in the pyrogenic action of corticotropin releasing hormone (CRH) in rats.

METHODS

Corticotropin releasing hormone, 2',3'-dideoxyadenosine (DDA) and adenosine-3',5'-(cyclic) monophosphorothionate, Rp-Isomer (Rp-cAMPS), were administered intracerebroventricularly (i.c.v.). The colonic temperature was measured using a thermistor, and the content of cAMP in the hypothalamus was determined by radioimmunoassay. Hypothalamic incubation was used to assess the effects of CRH on the content of cAMP in the hypothalamus in vitro.

RESULTS

Microinjection (i.c.v.) of CRH (2.5 micrograms, 5.0 micrograms and 10 micrograms) caused increases in colonic temperature and the hypothalamus cAMP level in conscious rats. CRH increased hypothalamus cAMP level in vitro. The pyrogenic effects of CRH were abolished or markedly inhibited by prior injection (i.c.v.) of an adenylate cyclase inhibitor, DDA (30 micrograms), or an inhibitor of cAMP-dependent protein kinase, Rp-cAMPS (15 micrograms).

CONCLUSION

cAMP mediates the pyrogenic action of centrally administered of CRH in rats, and protein kinase A may play an important role in the central CRH-induced fever. The cAMP-dependent protein kinase signal transduction pathway may be involved in the central mechanisms of the pyrogenic action of CRH in rats.

Quantitative amino acid analysis using a Beckman system gold HPLC 126AA analyzer

BACKGROUND

The Beckman 6300/7300 analyzer, which was widely used for amino acid (AA) analysis, is no longer commercially available.

METHODS

To set up an affordable AA analysis program, a Beckman system gold HPLC 126AA analyzer and Pickering Laboratories reagents were used. Two quantitative AA analysis programs were developed. One was an 18-min short program quantitating seven AAs from plasma and dried blood spots (DBS) specimens using Lithium eluents Li-365 and Li-375 at 70 degrees C column temperature. The short program could be used for diagnosis and follow-up dietary management for phenylketonuria (PKU), maple syrup urine disease (MSUD), tyrosinemia and homocystinuria patients. The second program was a 118-min long AA screening panel quantitating 40 AAs using Lithium eluents Li-275, Li-365 and Li-375 at 32, 48 and 72 degrees C column temperatures from plasma and urine specimens.

RESULTS

The values obtained from DBS specimens were in good agreement with certified results from the Centers for Disease Control and Prevention. The values obtained from plasma and urine samples were in good correlation with those obtained from Beckman 6300 analyzer (0.9076 < or = r < or = 0.999).

CONCLUSIONS

Amino acid quantitation from physiological samples using a Beckman 126AA Analyzer and Pickering Laboratories reagents was useful for clinical diagnosis and monitoring of aminoacidopathies.

[Cloning and expression of Trichoderma reesei endoglucanase III (EG III) gene in Saccharomyces cerevasiae]

Using Congo red-staining method, one positive clone with CMCase activity was isolated from the Trichoderma ressei cDNA gene bank constructed in Saccharomyces cerevasiae. Sequencing result showed that the 1.5 kb-length DNA fragment inserted in the recombinant plasmid encoded EG III gene from T. reesei. Enzymatic characterization of the EG III produced by recombinant S. cerevasiae was analyzed. The experimental results indicated that the optimum pH and temperature for EG III are 5.0 and 60 degrees C, respectively. The effects of secretory system components SSO 2 and SEB1 of S. cerevisiae on EG III secretion were examined. The results indicated that the amount of EG III secreted by the strain with SSO 2-overexpression was highest among the different recombinant S. cerevisiae strains, showed that SSO 2 is a rate-limiting component of the secretory machinery in the process of EG III secretion. Furthermore, the EG III expression level was increased 5.3 times by deletion. Furthermore, the EG III expression level was increased 5.3 times by deletion of the 98 bp in 5' untranslated region of eg3 mRNA sequence. This result suggested that the regulation region could exist in the 5' untranslated region of EG III mRNA, which is recognized by the gene expression related factors of S. cerevasiae.

[Clinicopathological features of malignant ovarian neoplasms arising from ovarian endometriosis: a report of 26 cases]

OBJECTIVE

To clarify the features of malignant ovarian neoplasms arising from ovarian endometriosis.

METHODS

A total of 26 women with malignant ovarian neoplasms arising from ovarian endometriosis were analyzed retrospectively.

RESULTS

Dysmenorrhea and pelvic mass were the most common clinical features. Among 18 cases who underwent B-ultrasound or color doppler ultrasound examination, solid foci in the pelvic masses were found in 10 cases. The main histologic types of ovarian malignancy were endometrioid adenocarcinoma and clear cell carcinoma. Microscopically atypical endometriosis with the tumors were found in 15 cases. International Federation of Gynecology and Obstetrics stage: stage I 21(81%) cases, stage II 3(12%) cases, stage III 2 (8%) cases.

CONCLUSIONS

Clinical diagnosis of malignant ovarian neoplasms arising from ovarian endometriosis in early stage is difficult, and B-ultrasound examination is more valuable for diagnosis. It is suggested that close serutiny of endometrial hyperplasia, cellular atypia and malignancy in ovarian endometriosis be essential to understand the origin and development of malignant neoplasms arising from ovarian endometriosis.

Down-regulation of L-type calcium channel in pups born to 52 kDa SSA/Ro immunized rabbits

Congenital heart block is considered a model of passively acquired autoimmune disease in which the mother generates anti-SSA/Ro and/or anti-SSB/La antibodies that cross the placenta and presumably injure the heart of developing fetus. CHB is accompanied by ECG abnormalities including AV block, sinus bradycardia, and ventricular dysfunction. Our previous data indicate that these abnormalities are caused by maternal autoantibody-mediated disturbance of L-type Ca channels. To investigate the consequence of chronic exposure of L-type Ca channels in newborn pups to maternal autoantibodies during pregnancy, we immunized female rabbits with human 52 kDa-SSA/Ro (Ro52) recombinant protein. ECG revealed that pups from the immunized group had varying degrees of conduction defects. In addition, I(CaL) density and protein were reduced in hearts of pups from the immunized group. Sera and purified IgG from immunized rabbits inhibited I(Ba) recorded from oocytes with expressed alpha(1C) and beta(2a) subunits of L-type Ca channel. Pups born to Ro52 immunized mothers exhibited down-regulation of L-type calcium channels in heart. The data provide new insight into the pathogenesis of congenital heart block.

Autoantibodies from mothers of children with congenital heart block downregulate cardiac L-type Ca channels

Congenital heart block (CHB) affects offspring of mothers with autoantibodies (positive IgG) to intracellular SSA/Ro and SSB/La ribonucleoproteins and is associated with high morbidity and mortality. Here, we show that maternal anti-Ro/La antibodies immunoreact with human fetal cardiomyocyte sarcolemma, recognize human L-type Ca channel alpha(1C)-protein and functionally inhibit expressed current in oocytes injected with alpha(1C) cRNA and Purkinje L-type Ca current. Furthermore, cardiac myocytes from pups born to SSA/Ro-immunized mice exhibited reduced L-type Ca current density. All together, the data establish that L-type calcium channel is a target for maternal antibodies and may provide a functional basis for the electrocardiographic abnormalities seen in infants with CHB.

[Empty nose syndrome]

OBJECTIVE

The aim of this article is to present the concept of empty nose syndrome(ENS) and help ENT doctors take care of regular nasal turbinate surgery.

METHODS

Fourteen patients who was diagnosed as ENS in our department were reviewed retrospectively. All patients had undergone various forms of nasal surgery (all had had turbinectomy). Their age ranged from 13 to 52 years. All patients were treated conservatively, among these patients 5 subjects who had more serious symptoms received submucous and subperiostal nasal implantation with ilium.

RESULTS

All patients had nasal obstruction and dryness of nasal cavity, nasopharynx and oto-pharynx in 6 months--5 years after their first nasal surgery, some presented symptoms of depression. Nasoscope examination showed all patients had a cylindrically enlarged nasal cavity. Conservative treatment was effective in most cases. The effectiveness of operative treatment was encouraging during short-term follow-up.

CONCLUSION

Extensive turbinectomy may cause secondary nasal mucosal atrophy and a series of subsequent symptoms. The presentation of this concept is to remind the ENT doctors prudently performing turbinectomy to avoid the occurrence of irreversible injury to the nasal cavity.

[Proliferation properties and telomerase activity of human embryonic tendon cells transformed by ptsA58H plasmid]

OBJECTIVE

To analysis the proliferation properties and telomerase activity of human embryonic tendon cells transformed by ptsA58H plasmid cultured in vitro continuously.

METHODS

The 40th, 70th, and 75th passages of transformed human embryonic tendon cells (THETC) were adopted. The collagen secretion of THETC was detected by immunohistochemical methods, the growth curve of different passages of THETC was compared, and chromosome karyotype was analyzed. Total RNA of THETC were extracted to detect human telomerase reverse transcriptase (hTERT) mRNA expression by RT-PCR technique.

RESULTS

When THETC were subcultured to 70 passages, the morphological characteristics of cells changed and began replicative senescence. THETC still could secret type I collagen normally. The chromosome of THETC was heteroploid (2n = 94). There were no hTERT mRNA expression.

CONCLUSION

SV40 transfection can not make human embryonic tendon cells immortalization, on the other hand, human embryonic tendon cells transformed by ptsA58H plasmid has no tendency of malignant transformation.

In vivo microdialysis in the visual cortex of awake cat. II: sample analysis by microbore HPLC-electrochemical detection and capillary electrophoresis-laser-induced fluorescence detection

Sampling and monitoring release of excitatory and inhibitory amino acids in the striate cortex of mammals will provide important information for visual system research. Two microbore high performance liquid chromatography-electrochemical detection methods and a capillary electrophoresis-laser induced fluorescence detection were developed to determine the inhibitory amino acid, gamma-aminobutyric acid and the excitatory amino acids, glutamate and aspartate in microdialysates of cat striate cortex. In the liquid chromatography method, samples were derivatized using OPA-TBT. Ten microliters of derivatized product was injected onto the microbore column (100 x 1 mm i.d., C8) for quantitative analysis. Electrochemical detection was employed. In the capillary electrophoresis method, samples were derivatized using fluorescein isothiocyanate and separated in borate buffer within 15 min, then detected by a laser-induced fluorescence detector.

In vivo microdialysis in the visual cortex of awake cat. III: histological verification

In vivo microdialysis sampling extracellular excitatory and inhibitory amino acids from the striate cortex of mammals will provide important information for visual system research. To facilitate the interpretation of microdialysis results, this protocol critically examines: (1) the location of probe implantation in the visual cortex using Nissl staining; (2) the morphological changes after probe implantation by visualization of neurons containing glutamate; (3) the morphological changes after probe implantation by visualization of gliosis using glial fibrillary acidic protein (GFAP) immunocytochemistry; (4) the implantation of the probe in sensory-deprived versus non-deprived cortical regions by visualization of neurons containing c-Fos protein after limited retinal lesion. The histochemical and immunocytochemical methods of Glu, GFAP and c-Fos used are described.

Prenatal diagnosis and characterization of an unbalanced whole arm translocation resulting in monosomy for 18p

Monosomy for the short arm of chromosome 18 is one of the most frequent autosomal deletions observed. While most cases result from terminal deletion of 18p, 16% of cases reported were as a result of an unbalanced whole arm translocation resulting in monosomy 18p. The origin and structure of these derivative chromosomes were reported in only a few cases. We report the prenatal diagnosis and characterization of a new case of monosomy 18p as a result of an unbalanced whole arm translocation. Amniocentesis was performed at 15 weeks of gestation on a 34-year-old woman initially referred for advanced maternal age. Holoprosencephaly was identified by ultrasound at the time of amniocentesis. Karyotype analysis showed an unbalanced whole arm translocation between the long arm of one chromosome 18 and the long arm of one chromosome 22, 45,XX,der(18;22)(q10;q10), in all metaphases. In effect, the fetus had monosomy for 18p. Parental karyotypes were normal, suggesting a de novo origin for the der(18;22). Fluorescence in situ hybridization (FISH) analysis was performed with alpha-satellite probes D18Z1 and D14Z1/D22Z1 to identify the origin of the centromere on the der(18;22). Signal was observed with both probes, indicating that the centromere was composed of alpha-satellite DNA from both constituent chromosomes. Genotyping of the fetus and her parents with chromosome 18p STS marker D18S391 showed only the paternal 187 bp allele was present in the fetus, indicating that it was the maternal chromosome 18 involved in the der(18;22). This case and previous reports show that de novo unbalanced whole arm translocations are more likely to retain alpha-satellite sequences from the two chromosomes involved.

In vivo microdialysis in the visual cortex of awake cat. I: surgery, animal training and sampling

Sampling and monitoring release of excitatory and inhibitory amino acids in the striate cortex of mammals will provide important information for visual system research. A method allowing repeated microdialysis in the cortical layers of area 17 of the awake cat is described. Under visual control through a surgical microscope and using a stereotactic instrument, four probe guides are permanently implanted in area 17 of one hemisphere of the anesthetized animal and two fixation bars are mounted on the skull to allow fixation of the cat in a stereotactic frame. The implantation of four probe guides in the same hemisphere allows simultaneous sampling from different cortical regions subserving different parts of the visual field. A removable transparent cover protects the probe guides. After recovery from surgery the awake cats are trained to adapt to a fixation in a stereotaxic apparatus. Once adapted to that situation, the cats are used for 5 h in vivo microdialysis experiments without anesthesia.

Effect of partial sensory deprivation on monoaminergic neuromodulators in striate cortex of adult cat

The role of monoaminergic neuromodulators in the reorganization of cortical topography following limited sensory deprivation in the adult cat was investigated. The total concentrations of dopamine, noradrenaline, serotonin and their major metabolites were measured in the visual cortex of both normal control and experimental animals using microbore high-performance liquid chromatography coupled with electrochemical detection. The experimental animals were subjected to a binocular retinal lesion corresponding to the central 10 degrees of vision and killed two weeks post-lesion. The sensory deprivation was confirmed in area 17 by measuring immediate-early gene zif-268 messenger RNA expression. Following the retinal lesion, the total concentrations of noradrenaline and dopamine were significantly higher in the non-deprived cortex of retinal lesion cats than in the deprived cortex of retinal lesion cats and the cortex of normal animals. This pattern follows the release of the excitatory neurotransmitter glutamate under the same conditions. Serotonin levels were significantly lower in the deprived cortex, and its metabolite 5-hydroxyindole-3-acetic acid was significantly higher in the non-deprived cortex than in deprived cortex and normal cortex. From these results, we suggest that the modulation of noradrenaline, dopamine and serotonin is regulated by visual afferent activity.

Kinetic analysis of the stepwise formation of a long-range DNA interstrand cross-link by a dinuclear platinum antitumor complex: evidence for aquated intermediates and formation of both kinetically and thermodynamically controlled conformers

Reported here is a detailed study of the kinetics and mechanism of formation of a 1,4 GG interstrand cross-link by [(trans-PtCl(NH(3))(2))(2)(mu-NH(2)(CH(2))(n)NH(2))](2+) (1,1/t,t (n = 6), 1), the prototype of a novel class of platinum antitumor complexes. The reaction of the self-complementary 12-mer duplex 5'-[d(ATATGTACATAT)(2)] with (15)N-1 has been studied at 298 K, pH 5.4, by [(1)H,(15)N] HSQC 2D NMR spectroscopy. Initial electrostatic interactions with the duplex are observed for 1 and the monoaqua monochloro species (2). Aquation of 1 to yield 2 occurs with a pseudo-first-order rate constant of (4.15 +/- 0.04) x 10(-5) s(-1). 2 then undergoes monofunctional binding to the guanine N7 of the duplex to form 3 (G/Cl) with a rate constant of 0.47 +/- 0.06 M(-(1) s(-1). There is an electrostatic interaction between the unbound [PtN(3)Cl] group of 3 and the duplex, which is consistent with H-bonding interactions observed in the molecular model of the monofunctional (G/Cl) adduct. Closure of 3 to form the 1,4 GG interstrand cross-link (5) most likely proceeds via the aquated (G/H(2)O) intermediate (4) (pseudo-first-order rate constant = (3.62 +/- 0.04) x 10(-5) s(-1)) followed by closure of 4 to form 5 (rate constant = (2.7 +/- 1.5) x 10(-3) s(-1)). When closure is treated as direct from 3 (G/Cl) the rate constant is (3.39 +/- 0.04) x 10(-5) s(-1). Closure is ca. 10-55-fold faster than that found for 1,2 GG intrastrand cross-link formation by the diaqua form of cisplatin. Changes in the (1)H and (15)N shifts of the interstrand cross-link 5 indicate that the initially formed conformer (5(i)) converts irreversibly into other product conformer(s) 5(f). The NMR data for 5(i) are consistent with a molecular model of the 1,4 GG interstrand cross-link on B-form DNA, which shows that the NH(2) protons have no contacts except with solvent. The NMR data for 5(f) show several distinct NH(2) environments indicative of interactions between the NH(2) protons and the DNA. HPLC characterization of the final product showed only one major product peak that was confirmed by ESI-FTICR mass spectroscopy to be a cross-linked adduct of (15)N-1 and the duplex. The potential significance of these findings to the antitumor activity of dinuclear platinum complexes is discussed.

Analysis of extracellular gamma-aminobutyric acid, glutamate and aspartate in cat visual cortex by in vivo microdialysis and capillary electrophoresis-laser induced fluorescence detection

To investigate the influence of a partial sensory deprivation on the extracellular concentration of amino acid neurotransmitters in cat visual cortex, a capillary electrophoresis method was developed for the quantification of gamma-aminobutyric acid (GABA), glutamate (Glu) and aspartate (Asp) in in vivo microdialysis samples of cat brain. Microdialysis samples from different regions of area 17 were obtained every 15-min using CMA 12 2-mm probes perfused with synthetic cerebrospinal fluid and derivatized using fluorescein isothiocyanate (FITC). Laser-induced fluorescence (LIF) detection was employed. Good selectivity was obtained with a borate buffer (20 mM, pH 10.25). The whole procedure, including the washing step takes only 15 min. The conditions for derivatization and separation were optimized. The parameters for validation such as linearity, precision and detection limit are also reported. The results are consistent with those of HPLC but, as the sample volumes needed are only 1--5 nl, a much better time resolution can be obtained.

A Bayesian approach to finite mixture models in bioassay via data augmentation and Gibbs sampling and its application to-insecticide resistance

After continued treatment with an insecticide, within the population of the susceptible insects, resistant strains will occur. It is important to know whether there are any resistant strains, what the proportions are, and what the median lethal doses are for the insecticide. Lwin and Martin (1989, Biometrics 45, 721-732) propose a probit mixture model and use the EM algorithm to obtain the maximum likelihood estimates for the parameters. This approach has difficulties in estimating the confidence intervals and in testing the number of components. We propose a Bayesian approach to obtaining the credible intervals for the location and scale of the tolerances in each component and for the mixture proportions by using data augmentation and Gibbs sampler. We use Bayes factor for model selection and determining the number of components. We illustrate the method with data published in Lwin and Martin (1989).

Cooperative changes in GABA, glutamate and activity levels: the missing link in cortical plasticity

Different intracortical mechanisms have been reported to contribute to the substantial topographic reorganization of the mammalian primary visual cortex in response to matching lesions in the two retinas: an immediate expansion of receptive fields followed by a gradual shift of excitability into the deprived area and finally axonal sprouting of laterally projecting neurons months after the lesion. To gain insight into the molecular mechanisms of this adult plasticity, we used immunocytochemical and bioanalytical methods to measure the glutamate and GABA neurotransmitter levels in the visual cortex of adult cats with binocular central retinal lesions. Two to four weeks after the lesions, glutamate immunoreactivity was decreased in sensory-deprived cortex as confirmed by HPLC analysis of the glutamate concentration. Within three months normal glutamate immunoreactivity was restored. In addition, the edge of the unresponsive cortex was characterized by markedly increased glutamate immunoreactivity 2-12 weeks postlesion. This glutamate immunoreactivity peak moved into the deprived area over time. These glutamate changes corresponded to decreased spontaneous and visually driven activity in unresponsive cortex and to strikingly increased neuronal activity at the border of this cortical zone. Furthermore, the previously reported decrease in glutamic acid decarboxylase immunoreactivity was found to reflect decreased GABA levels in sensory-deprived cortex. Increased glutamate concentrations and neuronal activity, and decreased GABA concentrations, may be related to changes in synaptic efficiency and could represent a mechanism underlying the retinotopic reorganization that occurs well after the immediate receptive field expansion but long before the late axonal sprouting.

[Changes of leukocyte rheologic characteristics and cell adhesion molecules in patients with multiple organ failure after severe trauma]

OBJECTIVE

To explore the changes of leukocyte rheologic characteristics and of cell adhesion molecule in patients with multiple organ failure (MOF) after severe trauma.

METHODS

By using the erythrocyte deformability apparatus, platelet and thrombus adhesion dual-purpose apparatus and enzyme-linked immunosorbent assay (ELISA), We measured the leukocyte deformability (LD), leukocyte adhesion function (LAF), leukocyte CD18 expression, soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule (sVCAM-1) concentration in 36 MOF patients, 31 trauma patients, and 35 to be controls.

RESULTS

The leukocyte filtration index (LFI), leukocyte adhesion rate (LAR), leukocyte CD18 expression, and sICAM-1 and sVCAM-1 concentration were significantly higher in MOF patients than in controls and trauma patients (F = 68.45 - 116.20, q = 12.161 - 21.374, P < 0.00), and the changes of these indicators in MOF deaths were more obvious than those in MOF survivors (t = 6.920 - 11. 665, P < 0.00). The LFI and LAR in MOF patients were positively related to leukocyte CD18 expression, sICAM-1, and sVCAM-1 concentration (r = 0.691 - 0.844, P < 0.001); LFI was positively related to LAR (r = 0.711, P < 0.001).

CONCLUSION

The abnormalities of leukocyte rheologic characteristics and CAMs might be closely related to the occurrence of MOF and the severity of pathologic changes.

[The modulation of type I collagen and its receptor system on biological characteristics of osteoblasts]

This paper addresses the question whether type I collagen-receptor system is necessary for the functional activity of osteoblasts. Through blocking type I collagen-receptor system by type I collagen antibody or integrin alpha 2 beta 1 antibody, the proliferation of osteoblasts was studied by cell count, the apoptosis was studied by flow cytometry, and the mRNA expressions of type I collagen, integrin alpha 2 beta 1 and osteocalcin were also detected by RT-PCR techniques. When type I collagen-receptor system was blocked, osteoblasts showed high apoptosis rate, lower growth kinetics and weak mRNA expression of type I collagen, integrin alpha 2 beta 1 and osteocalcin; the blocking effect was reversible. It suggests that type I collagen-receptor system is necessary for osteoblastic phenotype. The biomaterials for bone tissue engineering should be constructed according to the extracellular matrix of osteoblasts, which supply normal extracellular environment for osteoblasts.

Tetrasomy 15q25-->qter: cytogenetic and molecular characterization of an analphoid supernumerary marker chromosome

Tetrasomy for the distal long arm of chromosome 15 is a rare finding. It has been previously described in seven patients, all of whom had a supernumerary marker chromosome (SMC) derived from distal 15q. These SMC contained no apparent centromeres (C-band/alpha-satellite negative), and belong to a novel class of SMC with neocentromeres. We present the oldest surviving patient with tetrasomy for distal 15q. The proposita was a 10-year-old girl with moderate to severe mental retardation, absent speech, hypotonia, minor facial anomalies, unusual digits, and pigmentation anomalies. Mosaicism for a symmetrical SMC was identified in metaphases from lymphocytes and fibroblasts. Parental karyotypes were normal, indicating a de novo origin for the SMC. FISH with a whole chromosome paint for chromosome 15 showed that the SMC was derived entirely from chromosome 15. However, C-banding and FISH with chromosome 15 probes D15Z1, D15S11, SNRPN, and PML were all negative. FISH with the FES probe at 15q26 showed hybridization to both ends of the SMC. The marker was interpreted as an analphoid inverted duplication of 15q25-->qter containing a presumed neocentromere. Previous molecular studies suggested either a mitotic or paternal meiotic origin for these distal 15q SMC. However, molecular analysis with chromosome 15 polymorphic markers showed that the analphoid SMC(15) in the proposita originated from a maternal meiotic error. The origins and mechanisms involved in formation of these distal 15q SMC appear to be more diverse than for the proximal pseudodicentic SMC(15).