Structure elucidation of compounds extracted from the Chinese medicinal plant Patrinia heterophylla

For several hundred years, Patrinia heterophylla has been used in traditional Chinese medicine as a treatment for abscesses, hepatitis, tonsillitis, ulcers, etc. Recent research suggests that it may also have some anti-cancer activity. We have extracted five pure compounds from this plant; two known flavonols without bio-activity, one known isocoumarin glucoside that exhibits some cytotoxic activity toward HeLa cervical cancer cells, and two novel compounds that show considerable cytotoxic activity toward HeLa cells.

Some p53-binding proteins that can function as arbiters of life and death

Four sets of p53-binding proteins are discussed in this review. These are the E2F family, the ASPP family, Y-box-binding protein YB1, and the prolyl isomerase Pin1. Each appears to play a role in the decision by p53 to induce an arrest of cell proliferation or apoptosis and they may also be independent markers of cancer. Their activities appear to be linked with the cell cycle and they may also interact with each other. In this review, the properties of each protein class are discussed as well as how they affect p53 functions. A model is proposed as to how their activities might be coordinated.

Effects of a novel anti-exospore monoclonal antibody on microsporidialNosema bombycisgermination and reproductionin vitro

A monoclonal antibody (mAb) 3C2, against an exospore protein of the microsporidiumNosema bombycis(N. bombycis) was prepared, and its effects on microsporidial germination and reproductionin vitrowere studied. MAb 3C2 was effective in inhibiting the germination and subsequent infection ofBombyx moricells compared to the control mAb. The antigen was isolated by 2-dimensional gel electrophoresis. Immunoblotting revealed it to be an 84 kDa protein corresponding to pI (7·2) on the 2-D gel. The present results suggest that the antibodies can be used for diagnostic purposes and for developing new therapeutic strategies in controlling microsporidian diseases.

UNC5C is required for spinal accessory motor neuron development

In both invertebrates and vertebrates, UNC5 receptors facilitate chemorepulsion away from a Netrin source. Unlike most motor neurons in the embryonic vertebrate spinal cord, spinal accessory motor neuron (SACMN) cell bodies and their axons translocate along a dorsally directed trajectory away from the floor plate/ventral midline and toward the lateral exit point (LEP). We have recently shown that Netrin-1 and DCC are required for the migration of SACMN cell bodies, in vivo. These observations raised the possibility that vertebrate UNC5 proteins mediate the presumed repulsion of SACMN away from the Netrin-rich ventral midline. Here, we show that SACMN are likely to express UNC5A and UNC5C. Whereas SACMN development proceeds normally in UNC5A null mice, many SACMN cell bodies fail to migrate away from the ventral midline and inappropriately cluster in the ventrolateral spinal cord of mouse embryos lacking UNC5C. These results support an important role for UNC5C in SACMN development.

BM stem cell transplantation rescues pathophysiologic features of aged dystrophic mdx muscle

BACKGROUND

The value of transplantation of BM stem cells in aged (12-month-old) mdx was evaluated because it is thought to be a more ideal model for studying the praxiology of Duchenne muscular dystrophy (DMD). The possible mechanisms of stem cell differentiation were then discussed.

METHODS

BM was isolated from 8-10-week-old male C57 BL/10 mice. After injecting BM cells into 12-month-old female mdx mice through the tail vein, the expression of dystrophin and MyoD was detected at different time points by immunofluorescence staining, RT-PCR and Western blot.

RESULTS

The C57 male mice donor-specific and Y-chromosome-specific sequence could be detected in all female aged mdx mice, implying the success of the transplantation. Expression of dystrophin and MyoD was detected and increased over time.

DISCUSSION

BM cells were recruited to the muscle and partially restored specific pathophysiologic features of the dystrophic muscle in aged mdx mice. Muscle differentiation of BM cells recapitulated embryonic myogenesis.

Clinical implementation of chromosomal microarray analysis: summary of 2513 postnatal cases

BACKGROUND

Array Comparative Genomic Hybridization (a-CGH) is a powerful molecular cytogenetic tool to detect genomic imbalances and study disease mechanism and pathogenesis. We report our experience with the clinical implementation of this high resolution human genome analysis, referred to as Chromosomal Microarray Analysis (CMA).

METHODS AND FINDINGS

CMA was performed clinically on 2513 postnatal samples from patients referred with a variety of clinical phenotypes. The initial 775 samples were studied using CMA array version 4 and the remaining 1738 samples were analyzed with CMA version 5 containing expanded genomic coverage. Overall, CMA identified clinically relevant genomic imbalances in 8.5% of patients: 7.6% using V4 and 8.9% using V5. Among 117 cases referred for additional investigation of a known cytogenetically detectable rearrangement, CMA identified the majority (92.5%) of the genomic imbalances. Importantly, abnormal CMA findings were observed in 5.2% of patients (98/1872) with normal karyotypes/FISH results, and V5, with expanded genomic coverage, enabled a higher detection rate in this category than V4. For cases without cytogenetic results available, 8.0% (42/524) abnormal CMA results were detected; again, V5 demonstrated an increased ability to detect abnormality. Improved diagnostic potential of CMA is illustrated by 90 cases identified with 51 cryptic microdeletions and 39 predicted apparent reciprocal microduplications in 13 specific chromosomal regions associated with 11 known genomic disorders. In addition, CMA identified copy number variations (CNVs) of uncertain significance in 262 probands; however, parental studies usually facilitated clinical interpretation. Of these, 217 were interpreted as familial variants and 11 were determined to be de novo; the remaining 34 await parental studies to resolve the clinical significance.

CONCLUSIONS

This large set of clinical results demonstrates the significantly improved sensitivity of CMA for the detection of clinically relevant genomic imbalances and highlights the need for comprehensive genetic counseling to facilitate accurate clinical correlation and interpretation.

Region-specific transcriptional changes following the three antidepressant treatments electro convulsive therapy, sleep deprivation and fluoxetine

The significant proportion of depressed patients that are resistant to monoaminergic drug therapy and the slow onset of therapeutic effects of the selective serotonin reuptake inhibitors (SSRIs)/serotonin/noradrenaline reuptake inhibitors (SNRIs) are two major reasons for the sustained search for new antidepressants. In an attempt to identify common underlying mechanisms for fast- and slow-acting antidepressant modalities, we have examined the transcriptional changes in seven different brain regions of the rat brain induced by three clinically effective antidepressant treatments: electro convulsive therapy (ECT), sleep deprivation (SD), and fluoxetine (FLX), the most commonly used slow-onset antidepressant. Each of these antidepressant treatments was applied with the same regimen known to have clinical efficacy: 2 days of ECT (four sessions per day), 24 h of SD, and 14 days of daily treatment of FLX, respectively. Transcriptional changes were evaluated on RNA extracted from seven different brain regions using the Affymetrix rat genome microarray 230 2.0. The gene chip data were validated using in situ hybridization or autoradiography for selected genes. The major findings of the study are: 1. The transcriptional changes induced by SD, ECT and SSRI display a regionally specific distribution distinct to each treatment. 2. The fast-onset, short-lived antidepressant treatments ECT and SD evoked transcriptional changes primarily in the catecholaminergic system, whereas the slow-onset antidepressant FLX treatment evoked transcriptional changes in the serotonergic system. 3. ECT and SD affect in a similar manner the same brain regions, primarily the locus coeruleus, whereas the effects of FLX were primarily in the dorsal raphe and hypothalamus, suggesting that both different regions and pathways account for fast onset but short lasting effects as compared to slow-onset but long-lasting effects. However, the similarity between effects of ECT and SD is somewhat confounded by the fact that the two treatments appear to regulate a number of transcripts in an opposite manner. 4. Multiple transcripts (e.g. brain-derived neurotrophic factor (BDNF), serum/glucocorticoid-regulated kinase (Sgk1)), whose level was reported to be affected by antidepressants or behavioral manipulations, were also found to be regulated by the treatments used in the present study. Several novel findings of transcriptional regulation upon one, two or all three treatments were made, for the latter we highlight homer, erg2, HSP27, the proto oncogene ret, sulfotransferase family 1A (Sult1a1), glycerol 3-phosphate dehydrogenase (GPD3), the orphan receptor G protein-coupled receptor 88 (GPR88) and a large number of expressed sequence tags (ESTs). 5. Transcripts encoding proteins involved in synaptic plasticity in the hippocampus were strongly affected by ECT and SD, but not by FLX. The novel transcripts, concomitantly regulated by several antidepressant treatments, may represent novel targets for fast onset, long-duration antidepressants.

Galanin type 1 receptor knockout mice show altered responses to high-fat diet and glucose challenge

Galanin, a brain and pancreatic peptide with three receptor subtypes (GALR1, GALR2, and GALR3), is hypothesized to participate in energy homeostasis and glucoregulation. Hypothalamic galanin expression is induced by dietary fat, and intra-hypothalamic galanin administration has orexigenic/anabolic properties. Systemic galanin infusion alters glucoregulation in non-human species, partly through direct actions on pancreatic islets. However, the physiologic significance of endogenous galanin-GALR signaling is unclear. The present studies tested the hypotheses that GALR1 deficiency alters food intake and feed efficiency following switches to high-fat diet and that GALR1 deficiency alters whole-body glucose homeostasis. Adult, male GALR1 knockout (-/-), heterozygote (+/-), and C57BL/6J control (+/+) mice were studied. GALR1 deficiency impaired adaptation to a 3-day high-fat diet challenge, leading to increased food intake, feed efficiency and weight gain. However, during the following 2 weeks, GALR1 knockout mice decreased intake, consuming less daily energy than while maintained on low-fat diet and also than heterozygote littermates. Chow-maintained GALR1 knockout mice showed relative hyperglycemia in fed and d-glucose (i.p. 1.5 g/kg)-challenged states. GALR1 knockout mice showed normal food intake, feed efficiency and weight accrual on low-fat diets, normal fasted glucose levels, and normal glucose sensitivity to porcine insulin (i.p. 1 IU/kg) in vivo. The results support the hypotheses that galanin-GALR1 systems help adapt food intake and metabolism to changes in dietary fat and modulate glucose disposition in mice.

ASPP: a new family of oncogenes and tumour suppressor genes

The apoptosis stimulating proteins of p53 (ASPP) family consists of three members, ASPP1, ASPP2 and iASPP. They bind to proteins that are key players in controlling apoptosis (p53, Bcl-2 and RelA/p65) and cell growth (APCL, PP1). So far, the best-known function of the ASPP family members is their ability to regulate the apoptotic function of p53 and its family members, p63 and p73. Biochemical and genetic evidence has shown that ASPP1 and ASPP2 activate, whereas iASPP inhibits, the apoptotic but not the cell-cycle arrest function of p53. The p53 tumour suppressor gene, one of the most frequently mutated genes in human cancer, is capable of suppressing tumour growth through its ability to induce apoptosis or cell-cycle arrest. Thus, the ASPP family of proteins helps to determine how cells choose to die and may therefore be a novel target for cancer therapy.

A comparison of CFU-GM, BFU-E and endothelial progenitor cells using ex vivo expansion of selected cord blood CD133+ and CD34+ cells

BACKGROUND

CD133 is a newly developed hematopoietic stem cell marker but little is known about its function. Whether CD133(+) cell selection provides any advantage over CD34(+) selection for hematopoietic stem cell isolation and transplantation is unclear. The present study compared colony formation and endothelial cell differentiation of these two cell types from umbilical cord blood (UCB).

METHODS

Mononuclear cells from the same UCB samples were used for both CD133(+) and CD34(+) cell selection. Cells with 97.1% purity were incubated in semi-solid culture medium containing stem cell growth factor (SCGF) and G-CSF or erythropoietin (EPO). Purified cells were also cultured in M199 containing vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and insulin-like growth factor-1 (IGF-1).

RESULTS

CD34(+) and CD133(+) cells produced similar numbers of CFU-GM colonies (median 43.25 and 30.5, respectively; P>0.2). However, a greater than four-fold difference in BFU-E colony formation was observed from CD34(+) cells compared with CD133(+) cells (median 35 and 8, respectively; P<0.04). CD34(+) cells gave rise to endothelial-like cells when stimulated with VEGF, bFGF and IGF-1. CD133(+) cells were unable produce this cell type under the same conditions.

DISCUSSION

CD133(+) cells produced smaller BFU-E colonies and were unable to differentiate into mature endothelial cells. CD34(+) cells contained endothelial progenitors that could differentiate into mature cells of this lineage. Based on these data, it appears that CD133 offers no distinct advantage over CD34 as a selective marker for immunoaffinity-based isolation of hematopoietic stem cells and endothelial progenitor cells.

Structure-activity relationship studies on ADAM protein-integrin interactions

The ADAM (a disintegrin and metalloprotease) family of proteins possess multi-domain structures composed of a signal peptide, a prodomain, a metalloprotease domain, a disintegrin-like domain, a cysteine rich domain, an epidermal growth factor-like domain, a transmembrane domain and cytoplasmic tail. The disintegrin-like domain shares sequence similarity with the soluble venom disintegrins, a family of proteins which are potent inhibitors of integrin-mediated platelet aggregation and cell adhesion. Several ADAMs have been reported to interact with integrins, and the disintegrin-like domain may be crucial part in this respect. A description of structure-activity relationship of ADAM proteins interacting with integrin is outlined in this review. The review highlights recent reports on potential integrin family for ADAMs and how ADAMs selectively modulate interaction for integrin mediated cell function. Lastly, it describes progress in understanding the structural features and functional roles of the ADAMs in normal and pathological conditions and how this insight may assist the development of new therapeutic approaches.

Selective depletion of activated T cells by recombinant immunotoxin containing anti-CTLA-4 single-chain fragment of variable antibody and N-terminal fragment of perforin

We constructed a novel immunotoxin, hS83P34, by fusing the fragment containing the N-terminal 34 amino acids of human perforin to the C-terminal of humanized anti-CTLA-4 single chain fragment of variable antibody. In vitro cytotoxicity assays demonstrated that CTLA-4-positive activated human T cells and 6T-CEM were sensitive to hS83P34, while CTLA-4-negative resting T cells and endothelial cell ECV-304 were resistant to hS83P34. The IC50s of hS83P34 for activated T cells and 6T-CEM were about 0.2 micromol/L and 1.0 micromol/L, there was no obvious cytotoxicity of ECV-304 as detected at 8 micromol/L of hS83P34. In tumor graft rejection models, after treatment with 1.2 mg/kg immunotoxin every day for 12 days, the transplanted tumor cells were rescued by immunotoxin. The tumor weights of grafts of the rejection control group, nonrejection control group, and test group were 0.006 +/- 0.014 g, 0.261 +/- 0.048 g, and 0.135 +/- 0.056 g, respectively. In the early 3 days posttransplantation, there were a lot of CD4- and CD8-positive T cells infiltrating into the tumor grafts of the rejection control group, while only a few T cells were detected in the tumor grafts of the test group. According to these results, we concluded that immunotoxin hS83P34 selectively depleted activated T cells in vitro as well as in vivo in an acute rejection model.

Phenotypic features with p53 alterations related to human papillomavirus and prognostic evaluation in cervical cancer

Cervical cancer is one of the most common tumor affecting women worldwide. Human papillomavirus (HPV) was found to have a causal relationship with cervical cancer and its precursors. The interaction between HPV E6 protein and p53 was identified in in vitro studies. The aim of the study was to evaluate the prevalence of p53 alterations related to HPV infection and the prognostic significance of p53 alterations in cervical cancer. Studies were identified by a MEDLINE search, and all relevant articles were retrieved from 1991 to March 2004. The prevalence of p53 mutations is a rare event in cervical cancer. The correlation between p53 mutations and HPV or prognosis is controversial. Loss of heterozygosity (LOH) of p53 is more commonly found in cervical cancer and is related with the prognosis of this disease. There is no significant correlation between p53 polymorphism and development of cervical cancer. The p53 mutations were not commonly found in cervical cancer. LOH of p53 may contribute to the progression of this malignancy. p53 polymorphism failed to be an independent prognostic factor in predicting the outcome of patients with cervical cancer. Further, epidemiologic surveys should be undertaken in larger populations and in different geographical regions.

Reduction of leucocyte telomere length in radiographic hand osteoarthritis: a population-based study

BACKGROUND

Although age is the strongest predictor of osteoarthritis, the exact mechanism underlying this disorder remains elusive.

OBJECTIVE

To examine the association between leucocyte telomere length (LTL), a bio-indicator of ageing, and radiographic hand osteoarthritis.

METHODS

An unselected, predominantly female sample from the TwinsUK Adult Twin Registry (Twin Research and Genetic Epidemiology Unit, St Thomas Hospital, London, UK) was studied. Radiographs of both hands were obtained with a standard posteroanterior view and assessed for radiographic osteoarthritis according to the Kellgren/Lawrence (K/L) score. Individual radiographic features including osteophytes and joint space narrowing (JSN) were also assessed on a four-point scale using a standard atlas. Hand osteoarthritis was defined radiographically as having >or=3 osteoarthritis-affected joints of both hands (K/L score>or=2). Severity of hand osteoarthritis was indicated semiquantitatively by total K/L scores, osteophytes, JSN scores and proportion of joints affected. Mean LTL was measured by the terminal restriction fragment length using the Southern blot.

RESULTS

A total of 1086 Caucasian subjects (mean (SD) age 55 (8.0) years) were studied. LTL was 6.95 (0.64) kb and was inversely correlated with age. After adjustment for age, sex, body mass index and smoking, LTL was significantly shorter by 178 bp in subjects with hand osteoarthritis (n = 160) than in those without (n = 926; p = 0.04). LTL was also significantly associated with semicontinuous measures of osteoarthritis (eg, total K/L score, JSN score, osteophyte score and proportion of joints affected) after adjustment (all p<or=0.02) in a dose-response fashion.

CONCLUSION

Shorter LTL equivalent to around 11 years of annual loss in normal people is associated with radiographic hand osteoarthritis and disease severity, suggesting potential shared mechanisms between osteoarthritis and ageing, and implicating oxidative stress and low-level chronic inflammation in both conditions.

Quantitative structure-property relationship studies on electrochemical degradation of substituted phenols using a support vector machine

A quantitative structure-property relationship (QSPR) model has been developed for the electrochemical degradation of substituted phenols using a support vector machine (SVM). Thirty descriptors, including quantum chemical parameters, steric effect descriptors and half wave potential (E1/2), were used for describing twelve substituted phenols, including mono- and multi-substituent phenols. A leave-one-out (LOO) cross validation procedure resulted in the selection of three descriptors, the total of electron and nuclear energies of the two-center terms for the carbon-chlorine or carbon-nitrogen bond (TE2), the net atomic charges on the chlorine or nitrogen (qx), and the largest negative atomic charge on an atom (q-). The model based on SVM yielded a Q2 value of 0.892, indicating a high predictive ability. Compared with models developed with partial least squares (PLS) and multiple linear regression (MLR), where Q2 were 0.804 and 0.799 respectively, SVM showed higher performances.

Proteomic Analysis of the Genotoxicant Methylazoxymethanol (MAM)-Induced Changes in the Developing Cerebellum

The genotoxicant methylazoxymethanol (MAM) is a widely used developmental neurotoxin, and its glucoside is an etiological factor for western Pacific amyotrophic lateral sclerosis-parkinsonism-dementia complex (ALS/PDC). Identification of global protein expression changes that occur in response to MAM in the developing cerebellum could provide valuable insight into the potential mechanisms involved in the neurodegeneration process. We have utilized fluorescence 2-dimensional differential gel electrophoresis (2D-DIGE), to determine the protein expression changes that occur during normal cerebellar development and in response to MAM. Three day-old postnatal C57BL/6 mice (PND3) received a single injection of MAM, and the cerebella of postnatal day 4 (PND4) and day 22 (PND22) were analyzed. Approximately, 1400 unique spots were matched and quantified in all samples. Comparison of PND4 and PND22 developing cerebellum showed that a significant fraction of the proteome (approximately 68%) changes at this stage. The immediate response of the developing cerebellum to MAM was minimal (approximately 10%). However, significant differences (27%) were noted 14 days after MAM exposure. In contrast, the transcriptome changes were more pronounced at 24 h compared to 14 days. MAM targeted several proteins networks including transport (e.g., alpha-synuclein), cytoskeletal (e.g., beta-tubulin, vimentin), and mitochondrial (e.g., Atp5b) proteins. Immunochemistry confirmed several of the changes in protein expression (alpha-synuclein). Comparison with gene expression changes revealed that the temporal changes observed in the transcriptome and proteome are not correlative. These studies demonstrate for the first time the potential networks involved during neuronal development and neurodegenerative processes that are perturbed by MAM.

Identification of the Critical Role of Tyr-194 in the Catalytic Activity of a Novel N-Acyl-Homoserine Lactonase from Marine Bacillus cereus Strain Y2

Enzymatic disruption of quorum-sensing (QS) pathways in pathogenic organisms is a promising anti-infection therapeutic strategy. AHL-lactonase, a potent tool for biocontrol, can hydrolyze QS signal molecule N-acyl-homoserine lactones (AHLs) into inactive products, thereby blocking the QS systems. A marine bacterial isolate Y2, identified as a Bacillus cereus subsp., was found capable of inactivating AHLs. The aiiA gene encoding the AHL-degrading enzyme from bacterial strain Y2 was cloned and expressed in Escherichia coli. The 28-kDa recombinant Y2-AiiA protein was purified and showed strong AHL-degrading activity. Sequence comparisons of Y2-aiiA with known AHL-lactonases revealed high identities in the deduced amino-acid sequences. Functional determination of a potential catalytic residue Tyr-194 of AHL-lactonases was performed by site-directed mutagenesis. As judged by AHL-degrading bioassay, substitution of Tyr-194 with Ala resulted in a dramatic decrease of activity compared with wild-type (WT) recombinant Y2-AiiA, although the expression level of the mutated Y2-AiiA protein was equivalent to that of WT Y2-AiiA. These results suggested that the conserved residue Tyr-194 is critical for catalytic function of the novel AHL-lactonase.

Long-Term Results of Surgical Treatment of Tetralogy of Fallot in Adults

BACKGROUND

The long-term results of patients with tetralogy of Fallot surgically treated in adulthood were evaluated to define the real benefit of surgical correction.

METHODS

Between August 1990 and February 2004, 57 patients older than 18 years of age with tetralogy of Fallot received total correction. Forty-two patients (73.7 %) required transannular patch.

RESULTS

Hospital and late mortality were 7.0 % (n = 4) and 5.7 % (n = 3), respectively. One patient was reoperated on to close residual ventricular septal defect. Four patients were lost. Of the remaining 49 patients, the mean follow-up was 65 +/- 38 months (range 11 - 173 months). Actuarial survival was 97.4 +/- 2.5 %, 91 +/- 7 % and 72.8 +/- 17.1 % at 5, 10 and 14 years, respectively. At the latest follow-up, 35 (76.1 %) of the surviving patients presently have NYHA functional class I ( P < 0.01).

CONCLUSION

The overall survival of surgically treated adult patients with tetralogy of Fallot is acceptable. The greatest benefit of total correction at this age is the functional improvement.

Integrins in Drug Targeting-RGD Templates in Toxins

Integrins are a family of heterodimeric receptors, which modulate many cellular processes including: growth, death (apoptosis), adhesion, migration, and invasion by activating several signaling pathways. Integrin-binding RGD (arginine-glycine-aspartic acid) is found in several important extracellular matrix proteins which serve as adhesive integrin ligands. The RGD motif has also been found in many toxins from snake venom and other sources that specifically inhibit integrin binding function and serve as potent integrin antagonists, particularly of platelet aggregation and integrin-mediated cell adhesion. Many of these proteins have potential as therapeutic agents which can target integrins directly. Structural and functional studies of several RGD-containing toxins suggest that the inhibitory potency of these proteins lies in subtle positional requirements of the tripeptide RGD at the tip of a flexible loop, a structural feature for binding to integrins. In addition, amino acid residues in this loop in close vicinity to the RGD-motif determine the integrin-binding specificity and selectivity. This review will present a review of integrin structure and function, and of disintegrin structural features responsible for their activity as antagonists of integrin function. The use of integrins in drug targeting and integrins as targets for drug delivery by using the RGD as a template structure will also be discussed.