Formononetin induces cell cycle arrest of human breast cancer cells via IGF1/PI3K/Akt pathways in vitro and in vivo

Formononetin is one of the main components of red clover plants, and is considered as a typical phytoestrogen. This study further investigated that formononetin inactivated IGF1/IGF1R-PI3K/Akt pathways and decreased cyclin D1 mRNA and protein expression in human breast cancer cells in vitro and in vivo. MCF-7 cells were treated with different concentrations of formononetin. The proliferation of the cells treated with formononetin was tested by MTT assay. The cell cycle in the treated cells was examined by flow cytometry. The levels of p-IGF-1 R, p-Akt, and cyclin D1 protein expression and cyclin D1 mRNA expression in the treated cells were determined by Western blot and RT-PCR, respectively. In addition, the antitumor activity of formononetin was evaluated in nude mice bearing orthotopic tumor implants. Compared with the control, formononetin inhibited the proliferation of MCF-7 cells and effectively induced cell cycle arrest. The levels of p-IGF-1 R, p-Akt, cyclin D1 protein expression, and cyclin D1 mRNA expression were also downregulated. On the other hand, formononetin also prevented the tumor growth of human breast cancer cells in nude mouse xenografts. These results show that formononetin causes cell cycle arrest at the G0/G1 phase by inactivating IGF1/IGF1R-PI3K/Akt pathways and decreasing cyclin D1 mRNA and protein expression, indicating the use of formononetin in the prevention of breast cancer carcinogenesis.

Characterization and polymorphic analysis of 4.5 kb genomic full-length HLA-C in the Chinese Han population

This study used long-range polymerase chain reaction to sequence 4.5 or 4.3 kb of genomic DNA covering human leukocyte antigen C (HLA-C) and its flanks in 45 Chinese Han subjects to better characterize variation in the gene in a single population. Sequences of 35 HLA-C alleles were obtained from the population, including major alleles of 13 lineages of HLA-C. Four novel alleles, C*03:04:01:02, C*04:01:01:03, C*08:22, and C*17:01:01:02, were identified, and complete full-length sequences of 18 HLA-C alleles were obtained for the first time. All sequences herein reported also represent extensions through the promoter region and the 3'-untranslated region. Fourteen 5'-nucleotide sequences and 14 3'-nucleotide sequences were detected outside the coding region. In total, 316 single-nucleotide polymorphisms unequally distributed in HLA-C subregions were observed. In addition to exons 2 and 3, nucleotide variability was found to be particularly high in exon 5, which encodes the transmembrane region. The differentiation of the C*07 and C*17 lineages in this region accounts for the high variability. The congruence of phylogeny across most regions of the gene suggests that gene conversion or recombination has not markedly influenced divergence between lineages in the evolution of HLA-C.

Radiosensitization of MYC-overexpressing prostate cancer cells by statins

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Background: Studies have shown a link between HMG-CoA reductase inhibitors (statins) and decreased cancer risk in various cancers including prostate cancer. Recent clinical studies have shown improved outcome for men on statin therapy receiving definitive radiation therapy compared to radiation therapy alone for prostate cancer. The oncogene Ras can be inhibited by statin treatment and in turn also result in targeted downregulation of Myc. Inactivation of Myc has been shown to induce tumor regression in transgenic mouse models of different cancers.

Methods: Utilizing both in vitro and in vivo models, we studied in MYC over-expressing prostate cancer cells statin induced cytotoxicity and radiosensitization. We studied the effect of statin treatment with and without radiation treatment on in vitro cell death and clonogenic survival and correlated effects to levels of MYC and phospho-MYC. We constructed mutant cell lines to specifically examine the MYC-dependent effects of statins on prostate cancer cell cytotoxicity and radiosensitization. We performed similar studies in vivo using subcutaneous tumor grafts.

Results: Statin treatment alone of prostate cancer cells resulted in increased cell death and decreased clonegenic survival. Statin treatment further sensitized prostate cancer cells to ionizing radiation as shown through colony formation assays. These cellular effects were associated with decreased levels of active MYC as confirmed by western and phospho-western analysis. Statin-induced cell death and decreased MYC levels could be rescued with the HMG-CoA bypass product mevalonate. Finally, flank tumor graft experiments demonstrated the ability of statins and radiation to delay tumor growth in vivo.

Conclusions: Our preliminary data have implicated MYC as a potential critical target for the cytotoxic effects of statins on prostate cancer cells. The prevalence of MYC overexpression in human prostate cancers is as high as 80%. Thus the ability of statins to radiosensitize MYC overexpressing prostate cancer cells may provide a mechanistic explanation to the improved outcomes for men taking statins while on radiation therapy and now may afford us a molecular biomarker to examine this phenomenon in the clinic.

No significant financial relationships to disclose.

Resuscitation of warm ischaemia predamaged porcine kidneys by fibrinolytic preflush with streptokinase: reduction of animal experiments

In order to reduce the number of animal experiments, the use of non-heart-beating donors (NHBDs) from a commercial abattoir has been proposed. Since the use of slaughterhouse organs is legally not defined as animal experiment, this would fulfil international standards as an alternative to animal experiments. The development of intravascular thrombosis after cardiac arrest negatively impacts organ preservation and thus viability during ischaemic storage and reperfusion. A fibrinolytic preflush with streptokinase might overcome these limitations. Therefore, the functional and histomorphological integrity of kidneys preserved immediately with intact circulation (control group A) and kidneys preserved after cardiac arrest with a 30 min period of warm ischaemia (WI) (group B) was compared with kidneys preflushed with 12.5 kU/L (group C) or 50 kU/L streptokinase (group D) after 30 min WI prior to preservation. We could demonstrate that kidneys preflushed with 12.5 kU/L streptokinase (group C) performed better than those without streptokinase pretreatment after WI (group B). Parameters like oxygen consumption, perfusion pressure, laboratory values, lactate dehydrogenase level and lipidperoxidation were closer to that of the control (group A) than in groups B and D. The higher streptokinase concentration of 50 kU/L (group D) resulted histologically in a more pronounced tissue damage and an attenuated renal function, indicating toxic effects. On the basis of our results we believe streptokinase preflushed slaughterhouse kidneys to be an adequate alternative to organs from laboratory animals with the potential to further reduce the number of animal experiments.

c-Abl and Arg tyrosine kinases regulate lysosomal degradation of the oncoprotein Galectin-3

Galectin-3 (Gal3) has important roles in tumor transformation and metastasis. This study shows that c-Abl and Abl-related gene (Arg) associate with and phosphorylate Gal3. The SH (Src homology)3 domains of c-Abl/Arg bind to a P(80)GPPSGP motif of Gal3, and Tyr79 and Tyr118 are the major tyrosine phosphorylation sites. A consequence of this interaction and phosphorylation is the significant impairment of chaperone-mediated autophagy of Gal3. Cells expressing Gal3 and treated with the c-Abl/Arg inhibitor STI571, Gal3-depleted cells, and Gal3-depleted cells expressing Gal3 phosphorylation mutants all display an increased sensitivity to apoptosis-inducing agents. In addition, tumor cells expressing the phosphorylation mutants show impaired tumorigenicity. These results partially explain the antiapoptotic effect of Abl and Arg. As tumors frequently overexpress Gal3, a c-Abl/Arg-specific inhibitor may potentially be applied along with other antitumor drugs to target the lysosomal degradation of Gal3 in tumor therapy.

JWA regulates melanoma metastasis by integrin alphaVbeta3 signaling

JWA, a newly identified novel microtubule-associated protein (MAP), was recently demonstrated to be indispensable for the rearrangement of actin cytoskeleton and activation of MAPK cascades induced by arsenic trioxide (As(2)O(3)) and phorbol ester (PMA). JWA depletion blocked the inhibitory effect of As(2)O(3) on HeLa cell migration, but enhanced cell migration after PMA treatment. As cancer cell migration is a hallmark of tumor metastasis and the functional role of JWA in cancer metastasis is not understood, here we show that JWA has an important role in melanoma metastasis. Our data demonstrated that JWA knockdown increased the adhesion and invasion abilities of melanoma cells. Furthermore, JWA knockdown in B16-F10 and A375 melanoma cells significantly promoted the formation and growth of metastatic colonies in vivo. Moreover, in the tumor biopsies from human melanoma patients, JWA expression was significantly decreased in malignant melanoma compared with normal nevi. In addition, we found that JWA knockdown could intensify tumor integrin alpha(V)beta(3) signaling by regulating nuclear factor Sp1. These findings suggest that JWA suppresses melanoma metastasis and may serve a potential therapeutic target for human melanoma.

Genomic full length sequence of HLA-Cw*030301, identified by cloning and sequencing

Genomic full length sequence of human leukocyte antigen (HLA)-Cw*030301 that differs from Cw*030401 by two-nucleotide exchange at nt 473 (G>A) in exon 2 and nt 3033 (G>C) in 3'UTR, was identified by cloning and sequencing from a male Chinese donor.

A novel HLA-Cw*04 allele, Cw*04010103, identified by genomic full length cloning and sequencing

A novel human leukocyte antigen-Cw*04 allele, Cw*04010103, was identified by genomic full length cloning and sequencing from a male Chinese donor. It differs from the closest related allele Cw*04010101 by one nucleotide exchange at nt 1111 (G>A) in intron 3.

Phylogenetic relationships among the species of Elymus sensu lato in Triticeae (Poaceae) based on nuclear rDNA ITS sequences

The genus Elymus L. sensu lato includes Roegneria, Elymus, Hystrix, Sitanion and Kengyilia, and they are very important group in the tribe Triticeae. However, the phylogenetic relationships and taxonomic status of them are still in dispute. The ITS sequences were obtained and analyzed for their phylogenetic relationships by using Maximum Parsimony (MP) and Bayesian Inference (BI) methods. The main results were as follows: (1) Most species in Roegneria, Elymus and Sitanion were clustered in the St clade with diploid St genome species, and it was difficult to distinguish the species in Roegneria and Elymus; (2) The polyploid species with St genomes in the St clade were divided into three groups, which suggests that there exists differentiation of St genome in polyploids; (3) Most species of Kengyilia have only P-type of clone and clustered with diploid Agropyron species, which may suggest that Kengyilia is a valid genus; (4) Hy. patula, the type species of Hystrix was clustered with species of Elymus, while Hy. duthiei ssp. duthiei, Hy. duthiei ssp. longearistata, Hy. coreana and Hy. komarovii were grouped with diploid Psathyrostachys species. It indicated that Hy. patula is distinct related to other Hystrix species, and it is reasonable to treat Hystrix patula as Elymus hystrix and other species in Hystrix should be transferred to Leymus; (5) The "clones bias" in ITS sequences are widespread in the allopolyploid species.

Multiple roles of the p75 neurotrophin receptor in the nervous system

The p75 neurotrophin receptor (p75NTR) is a transmembrane protein that binds nerve growth factor (NGF) and has multiple functions in the nervous system where it is expressed widely during the developmental stages of life, although expression decreases dramatically by adulthood. Expression of p75NTR can increase in pathological states related to neural cell death. p75NTR is a member of the tumour necrosis factor (TNF) receptor family and it consists of intracellular, transmembrane and extracellular domains which are different from other TNF receptors. Either by interacting with tropomyosin receptor kinase (Trk) receptors or via the independent binding of neurotrophin, p75NTR can induce neurite outgrowth and cellular survival or cell apoptosis through several complicated signal transduction pathways. Most of these signalling pathways remain to be elucidated. By interacting with different cellular factors, p75NTR can induce neuron growth cone collapse or regrowth. p75NTR is also expressed in a variety of glial populations. The many functions of p75NTR require further study.

Clinical trial: effect of active lactic acid bacteria on mucosal barrier function in patients with diarrhoea-predominant irritable bowel syndrome

BACKGROUND

The intestinal permeability is increased in patients with diarrhoea-predominant irritable bowel syndrome (D-IBS).

AIM

To determine the possible efficacy of lactic acid bacteria on the increased intestinal permeability in D-IBS.

METHODS

Treatment was employed for 4 weeks in a randomized single blind placebo controlled study with 30 D-IBS patients. Patients were given either probiotic fermented milk (Streptococcus thermophilus, Lactobacillus bulgaricus, Lactobacillus acidophilus and Bifidobacterium Longum) or milk beverage containing no bacteria. The clinical symptoms were scored and intestinal permeability was measured by a triple sugar test before and after treatment.

RESULTS

Small bowel permeability was measured as the ratio of lactulose and mannitol recovery and colonic permeability was measured as the total mass of sucralose excretion (mg). After probiotics treatment, small bowel permeability decreased significantly from 0.038 (0.024) at baseline to 0.023 (0.020) (P = 0.004), the proportion of patients with increased small bowel permeability was lower than baseline (28.6% vs. 64.3%, P = 0.023). However, colonic permeability improved neither in the probiotics group nor in the placebo group at week 4. Treatment with probiotics significantly decreased the mean global IBS scores compared with the baseline scores (9.62 +/- 1.05 vs. 7.64 +/- 1.24, P < 0.001).

CONCLUSION

Short-term active lactic acid bacteria treatment for D-IBS improved mucosal barrier function.

Isolation and characterization of 19 microsatellite markers in a tropical and warm subtropical birch, Betula alnoides Buch.-Ham. ex D. Don

Betula alnoides is an ecologically and economically important species in the tropics and warm subtropics. Nineteen polymorphic microsatellite markers were isolated from this species, which displayed three to 12 alleles per locus. The observed heterozygosities ranged from 0.100 to 0.905, and the expected heterozygosities from 0.510 to 0.893. These markers would be useful tools in genetic resource assessment, molecular marker-assistant breeding, parentage analysis and genetic diversity studies for this species.

Effects of cross-link breakers, glycation inhibitors and insulin sensitisers on HDL function and the non-enzymatic glycation of apolipoprotein A-I

AIMS/HYPOTHESIS

Hyperglycaemia, a key feature of diabetes, is associated with non-enzymatic glycation of plasma proteins. We have shown previously that the reactive alpha-oxoaldehyde, methylglyoxal, non-enzymatically glycates apolipoprotein (Apo)A-I, the main apolipoprotein of HDL, and prevents it from activating lecithin:cholesterol acyltransferase (LCAT), the enzyme that generates almost all of the cholesteryl esters in plasma. This study investigates whether the glycation inhibitors aminoguanidine and pyridoxamine, the insulin sensitiser metformin and the cross-link breaker alagebrium can inhibit and/or reverse the methylglyoxal-mediated glycation of ApoA-I and whether these changes can preserve or restore the ability of ApoA-I to activate LCAT.

METHODS

Inhibition of ApoA-I glycation was assessed by incubating aminoguanidine, pyridoxamine, metformin and alagebrium with mixtures of methylglyoxal and discoidal reconstituted HDL (rHDL) containing phosphatidylcholine and ApoA-I, ([A-I]rHDL). Glycation was assessed as the modification of ApoA-I arginine, lysine and tryptophan residues, and by the extent of ApoA-I cross-linking. The reversal of ApoA-I glycation was investigated by pre-incubating discoidal (A-I)rHDL with methylglyoxal, then incubating the modified rHDL with aminoguanidine, pyridoxamine or alagebrium.

RESULTS

Aminoguanidine, pyridoxamine, metformin and alagebrium all decreased the methylglyoxal-mediated glycation of the ApoA-I in discoidal rHDL and conserved the ability of the particles to act as substrates for LCAT. However, neither aminoguanidine, pyridoxamine nor alagebrium could reverse the glycation of ApoA-I or restore its ability to activate LCAT.

CONCLUSIONS/INTERPRETATION

Glycation inhibitors, insulin sensitisers and cross-link breakers are important for preserving normal HDL function in diabetes.

CD40L disruption enhances Abeta vaccine-mediated reduction of cerebral amyloidosis while minimizing cerebral amyloid angiopathy and inflammation

Amyloid-beta (Abeta) immunization efficiently reduces amyloid plaque load and memory impairment in transgenic mouse models of Alzheimer's disease (AD). Active Abeta immunization has also yielded favorable results in a subset of AD patients. However, a small percentage of patients developed severe aseptic meningoencephalitis associated with brain inflammation and infiltration of T-cells. We have shown that blocking the CD40-CD40 ligand (L) interaction mitigates Abeta-induced inflammatory responses and enhances Abeta clearance. Here, we utilized genetic and pharmacologic approaches to test whether CD40-CD40L blockade could enhance the efficacy of Abeta(1-42) immunization, while limiting potentially damaging inflammatory responses. We show that genetic or pharmacologic interruption of the CD40-CD40L interaction enhanced Abeta(1-42) immunization efficacy to reduce cerebral amyloidosis in the PSAPP and Tg2576 mouse models of AD. Potentially deleterious pro-inflammatory immune responses, cerebral amyloid angiopathy (CAA) and cerebral microhemorrhage were reduced or absent in these combined approaches. Pharmacologic blockade of CD40L decreased T-cell neurotoxicity to Abeta-producing neurons. Further reduction of cerebral amyloidosis in Abeta-immunized PSAPP mice completely deficient for CD40 occurred in the absence of Abeta immunoglobulin G (IgG) antibodies or efflux of Abeta from brain to blood, but was rather correlated with anti-inflammatory cytokine profiles and reduced plasma soluble CD40L. These results suggest CD40-CD40L blockade promotes anti-inflammatory cellular immune responses, likely resulting in promotion of microglial phagocytic activity and Abeta clearance without generation of neurotoxic Abeta-reactive T-cells. Thus, combined approaches of Abeta immunotherapy and CD40-CD40L blockade may provide for a safer and more effective Abeta vaccine.

Characterization of HLA-B*5516, -B*1313, -B*9512, and -DRB1*1457 alleles identified in a southwest Chinese population

The human leukocyte antigen (HLA)-B*5516 allele differs from the B*5502 by a single 97 T --> C substitution (His to Tyr at position 33) in exon 2. The B*1313 allele results from 419 T --> A and 420 A --> C substitutions, encoding a Leu to Tyr substitution at 140 in exon 2 of the B*1301 allele. The B*9512 allele differs from B*1502 by a single 360 G --> C substitution (Gln to His at 120) in exon 3. The DRB1*1457 allele appears to be a hybrid molecule generated by recombination between the DRB1*13 and DRB1*14 alleles. The serological equivalents of these new alleles are HLA-B22, -B13, -B15, and DR13, respectively. Family studies detected two rare haplotypes: A*11, B*9512, DRB1*14 and A*24, B*52, Cw*07, DRB1*1457, DRB3*020201, DQB1*050301. The gene frequencies of these alleles in the Chinese population are less than 0.0001.

An N-methyl-D-aspartate receptor mediated large, low-frequency, spontaneous excitatory postsynaptic current in neonatal rat spinal dorsal horn neurons

Examples of spontaneous oscillating neural activity contributing to both pathological and physiological states are abundant throughout the CNS. Here we report a spontaneous oscillating intermittent synaptic current located in lamina I of the neonatal rat spinal cord dorsal horn. The spontaneous oscillating intermittent synaptic current is characterized by its large amplitude, slow decay time, and low-frequency. We demonstrate that post-synaptic N-methyl-D-aspartate receptors (NMDARs) mediate the spontaneous oscillating intermittent synaptic current, as it is inhibited by magnesium, bath-applied d-2-amino-5-phosphonovalerate (APV), or intracellular MK-801. The NR2B subunit of the NMDAR appears important to this phenomenon, as the NR2B subunit selective NMDAR antagonist, alpha-(4-hydroxphenyl)-beta-methyl-4-benzyl-1-piperidineethanol tartrate (ifenprodil), also partially inhibited the spontaneous oscillating intermittent synaptic current. Inhibition of spontaneous glutamate release by the AMPA/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) or the mu-opioid receptor agonist [D-Ala2, N-Me-Phe4, Gly5] enkephalin-ol (DAMGO) inhibited the spontaneous oscillating intermittent synaptic current frequency. Marked inhibition of spontaneous oscillating intermittent synaptic current frequency by tetrodotoxin (TTX), but not post-synaptic N-(2,6-dimethylphenylcarbamoylmethyl)triethylammonium bromide (QX-314), suggests that the glutamate release important to the spontaneous oscillating intermittent synaptic current is dependent on active neural processes. Conversely, increasing dorsal horn synaptic glutamate release by GABAA or glycine inhibition increased spontaneous oscillating intermittent synaptic current frequency. Moreover, inhibiting glutamate transporters with threo-beta-benzyloxyaspartic acid (DL-TBOA) increased spontaneous oscillating intermittent synaptic current frequency and decay time. A possible functional role of this spontaneous NMDAR-mediated excitatory postsynaptic current in modulating nociceptive transmission within the spinal cord is discussed.

Band engineering and periodic defects doping by lattices compounding

Our numerical simulation results demonstrate that 2D lattices compounding can create either a broad single complete photonic band gap or both first and second order complete band gaps. The results also show that photonic band gap properties are dependent on both the parameters of the single lattices and the relative position of the two compound lattices. Furthermore, if a compound structure is composed of two sets of lattices, the one with a larger periodic constant (a2) will serve as defects. While the defect modes are direction independent as a2 > 5 a, they are direction dependent as a2 < 5 a. Moreover, by optimizing of the rod size of the lattice with a2, many kinds of defect modes can be obtained to satisfy the different applications. The transmitted spectra and reflected spectra of this kind of structures demonstrate that the transmittances of the defect modes are dependent a2.

Halobacillus dabanensis sp. nov. and Halobacillus aidingensis sp. nov., isolated from salt lakes in Xinjiang, China

Two moderately halophilic spore-forming bacteria were isolated from salt lakes in the Xinjiang region of China. The two strains, designated AD-6T and D-8T, were aerobic, Gram-positive, rod-shaped and motile by means of peritrichous flagella. Strains AD-6T and D-8T grew in the presence of 0·5–20 % and 0·5–25 % (w/v) NaCl in complex medium, respectively. Their cell-wall peptidoglycan was of the l-orn–d-Asp type. The major menaquinone found in both strains was menaquinone-7 (MK-7). The fatty acid profile contained a large amount of branched fatty acids; the main fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C15 : 0 and iso-C16 : 0. The DNA G+C content of strains D-8T and AD-6T was 41·4 and 42·2 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains D-8T and AD-6T were located in the genus Halobacillus. Levels of 16S rRNA gene sequence similarity between the isolated strains and the type strains of Halobacillus species were in the range 96·2–99·5 %. DNA–DNA relatedness values of 17·0–52·2 % were found between the two strains and other Halobacillus species. The DNA–DNA relatedness value between D-8T and AD-6T was 50·6 %. On the basis of phenotypic and chemotaxonomic properties, phylogenetic analysis and genomic distinctiveness, strains D-8T and AD-6T should be placed in the genus Halobacillus as two novel species, for which the names Halobacillus dabanensis sp. nov. (type strain=JCM 12772T=CGMCC 1.3704T) and Halobacillus aidingensis sp. nov. (type strain=JCM 12771T=CGMCC 1.3703T) are proposed, respectively.

Signal transduction mediating gene expression of SP1, LHbeta-subunit and GH in response to GnRH or GHRH in the postnatal and fetal porcine anterior pituitary in vitro

To clarify signal transduction pathways mediating putative gene expression of transcription factor SP1 (selective promoter factor 1 or specificity protein 1) by GnRH or GHRH porcine anterior pituitary monolayer cultures were exposed for various time periods to GnRH, GHRH, activators of adenylate cyclase (AC) or proteinkinase C (PKC), and mRNA levels of SP1, LHbeta-subunit, and GH were determined by multiplex RT-PCR. In many experiments LH and GH release were measured as well for comparison. Another approach was to inactivate AC, PKC, or proteinkinase A (PKA) by specific inhibitors, MDL, GFX, and H89, respectively. Postnatally (4 weeks) SP1 mRNA level was maximally increased by GnRH, GHRH and both by activation of AC or PKC after 2 h of exposure. Two-hour stimulation of SP1 mRNA levels by dbcAMP was totally blocked by H89, while this inhibitor not clearly blocked GHRH stimulated SP1 mRNA levels. Stimulation of LHbeta mRNA by GnRH was suppressed by inactivation of AC or of PKC but not by inactivation of PKA. Inactivation of AC or PKA but not of PKC inhibited GHRH induced GH mRNA. Already at day 50 of fetal life (and likewise day 80) SP1 mRNA levels were stimulated by GHRH or activation of AC, but not by GnRH or activation of PKC. The results are consistent with the notion that SP1 plays an important role 1) in conferring GnRH responsiveness to the LHbeta-subunit gene by mediating the actions of both AC and PKC and 2) in conferring GHRH responsiveness to the GH gene through activation of the AC probably PKA pathway. Furthermore, the data are in line with the view that the GHRH/AC/SP1/GH pathway develops earlier during fetal life than the GnRH/PKC/SP1/LHbeta pathway.

Cross-section measurement of charged-pion photoproduction from hydrogen and deuterium

We have measured the differential cross section for the gamman-->pi(-)p and gammap-->pi(+)n reactions at theta(c.m.)=90 degrees in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at E(gamma) greater, similar 3.3 GeV exhibit a global scaling behavior for both pi(-) and pi(+) photoproduction, consistent with the constituent counting rule and the existing pi(+) photoproduction data. Possible oscillations around the scaling value are suggested by these new data. The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi(-) to pi(+) photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams.

Spine needle biopsy simulator using visual and force feedback

OBJECTIVE

Biopsy with an inserted needle is an important procedure for lesion detection in the spine, but is difficult to perform due to the presence of many critical organs near the spine. This article presents a spine needle biopsy simulator, based on visual and force feedback, which can be used to plan the optimal path of a needle and to practice the procedure without risk.

MATERIALS AND METHODS

The simulator is composed of a 3D human model, a visual-feedback component, a force-feedback component, and an evaluation module. The human model is based on 3D CT data. The visual-feedback component provides an oblique section, multiplanar reformatting images, and a volume-rendered image. Of these, the oblique section display is very useful for planning a 3D path for the needle. During simulation, the force-feedback component generates and provides realistic forces acting on the biopsy needle in real time by synchronizing them to visual feedback. After each simulation, the evaluation module provides a performance analysis for the trainee.

RESULTS

For an XCT abdomen volume data set of 256 x 256 x 256, the update rate of image rendering due to needle movement is over 25 Hz, with a force-feedback rate of 1 kHz. This performance proved to be good enough for the trainee to learn the relationship between visual and force feedback.

CONCLUSIONS

The simulator is useful for the planning of and training in complicated 3D spine needle biopsy procedures. It may be used as an educational tool for beginners, a practice tool to increase expertise, or a test bed for new procedures.

Investigating the distribution of prostate cancer using three-dimensional computer simulation

The objective of this work was to investigate the distribution of prostate cancer using three-dimensional (3-D) computer simulation. Two hundred and eighty-one 3-D computer prostate models were constructed from radical prostatectomy specimens. An algorithm was developed which divided each model into 24 symmetrical regions, and it then detected the presence of tumor within an individual region. The distribution rate of prostate cancer was assessed within each region of all 281 prostate models, and the difference between the rates was statistically analyzed using Mantel-Haenszel methodology. There was a statistically significant higher distribution rate of cancer in the posterior half (57.2%) compared to the anterior half ( 40.5%; P=0.001). The base regions (36.8%) had a statistically significant lower distribution rate than either the mid regions (56.3%; P=0.001) or the apical regions (53.5%; P=0.001). The mid regions did have a statistically significant higher distribution rate compared to the apical regions (P=0.032). There was no statistically significant difference between the distribution rate on the left half (48.5%) compared to that on the right half (49.2%; P=0.494). The spatial distribution of prostate cancer can be analyzed using 3-D computer prostate models. The results illustrate that prostate cancer is least commonly located in the anterior half and base regions of the prostate. Through an analysis of the spatial distribution of prostate cancer, we believe that new optimal biopsy strategies and techniques can be developed.

Conformational analysis of thiopeptides: free energy calculations on the effects of thio-substitutions on the conformational distributions of alanine dipeptides

When the oxygen atom in a peptide bond is replaced by a sulfur atom, the restriction in the available conformational space and the ability of thioamides to confer resistance to enzymatic degradation renders thioamides as potentially useful building blocks for drug design and protein engineering. The solvation free energy differences between conformers of the same dipeptide can be high. Yet, previous conformational studies, basing on the (phi, psi) conformational energy maps of thio-substituted dipeptides, neglected both explicit water interactions and free energy considerations. In this paper, the (phi, psi) conformational free energy maps are obtained by single umbrella sampling in an explicit water environment for both alanine dipeptide and the corresponding thioamide derivatives. The phi and psi angles for the minima in the relative energy maps calculated with dielectric of 80 are similar to the corresponding phi and psi angles in the relative free energy maps for both Ac-Ala-NHMe (Ac: acetyl; Ala: alanine) and Act-Alat-NHMe (Act: thio-acetyl; Alat: thio-alanine). However, some large differences between the relative energy and relative free energy of major minima indicate that the consideration of free energy is important in determination of the relative occupancy of particular minima. Free energy maps for both Ac-Ala-NHMe and Act-Alat-NHMe show that thio-substitution favors conformations where phi < 0 because of the deeper beta and alphaR minima. The changes in the position and relative stability of minima were explained in terms of the destabilization of the regions near phi = -120, 0 and 120, psi = 60, -60, 180, which correspond to the increased steric hindrance due to the bulkier sulfur atom.

[Evaluating wall motion of dilated cardiomyopathy by pulsed-wave Doppler tissue imaging]

OBJECTIVE

To evaluate the characteristics of wall motion in cases of dilated cardiomyopathy (DCM) by the use of Doppler tissue imaging (DTI).

METHODS

We observed 30 DCM patients and 30 normal volunteers. For the assessment of short axis motion, the myocardial velocities (MV) and transmural myocardial velocity gradients (MVG) of the middle segments of anterior interventricular septum and left ventricular posterior wall were recorded through parasternal long axis view. We detected the MV of the middle segments of left ventricular walls to evaluate the long axis motion through apical windows(4-chamber, 2-chamber and long axis).

RESULTS

Four kinds of abnormal presentations of the waves were seen in DCM cases. The patients' MV of were obviously lower as compared with the controls', especially in long axis; the patients' MVG also decreased significantly (P < 0.05). In the patient group, the heterogeneity of wall motion disappeared too.

CONCLUSION

PW-DTI can quantitatively assess the above abnormalities of DCM and provide supplementary information for clinical use.

Detailed-term-accounting-approximation calculations of the radiative opacity of laser-produced Al plasmas

An extensive configuration interaction (CI) scheme and the R-matrix method are combined to calculate the radiative opacity for laser-produced aluminum plasma in local thermodynamic equilibrium using the detailed-term-accounting (DTA) approximation. The CI scheme is used to obtain the absorption oscillator strengths of the electric dipole allowed transitions for evaluating the bound-bound absorption cross sections, and the R-matrix method is used to obtain the bound-free absorption (photoionization) cross sections. For an aluminum plasma at a temperature of 20 eV and the density of 0.01 g/cm(3), the Rosseland and Planck mean opacities are calculated to be 4184 and 24891 cm(2)/g, respectively, by integrating the spectrally resolved opacities with Rosseland and Planck weighting functions. The two mean opacities are also obtained by using the average atom model, and they are 22520 and 30402 cm(2)/g, respectively. The optical transmission from the photon energy of 70-250 eV, which was experimentally measured by Winhart et al. [G. Winhart et al. Phys. Rev. E 53, R1332 (1996)], is also calculated. Generally good agreement is found between our DTA and experimental transmission. Our theoretical result reproduces all structures shown in the experiment, whereas some of the structures near the higher energy edge did not show up in some other opacity models. These structures are attributed to the detailed treatment of the photoionization process.

[A comparison between the effects of albuterol and isoproterenol in bronchodilation test]

OBJECTIVE

To compare albuterol with isoproterenol as a bronchodilator in pulmonary function test and their value in the diagnosis and differential diagnosis of asthma.

METHODS

Two groups (59 patients with asthma and 37 patients with COPD) were included in this study, and the patients of each group were randomly divided into 2 subgroups. The patients in the 2 subgroups inspired the two drugs in a cross-over by odd or even days. The pulmonary functions were evaluated.

RESULTS

The changing rates of pulmonary functions induced by the two drugs in the two groups were positively correlated (P < 0.005), The changing rates of FEV1, MMEF, Raw, sGaw induced by albuterol were higher than the ones induced by isoproterenol in patients with asthma(P < 0.02), however the changing rates of FVC and PEF in asthma cases and all the above parameters in COPD cases were not significantly different between the two drugs(P > 0.10). The comparison of positive case number between asthma and COPD cases induced by both drugs showed significant difference(P < 0.005); especially, when the positive rate of sGaw induced by albuterol in asthma cases reached 98%, the positive rates in COPD cases was generally much lower.

CONCLUSION

Bronchodilation test is a valuable diagnostic method for asthma. In this study, albuterol was superior to isoproterenol. The most sensitive index in bronchodilation test was sGaw, then in order, FEV1(92%), MMEF and Raw; the FVC and PEF were relatively insensitive.

[The effect of leukotriene antagonist on the parameters of dose-response curve obtained after methacholine challenge test]

OBJECTIVE

To investigate the effect of leukotriene antagonist (zafirlucast) on the parameters of dose-response curve (DRC) obtained after methacholine challenge test.

METHODS

A therapy trial was conducted with the use of zafirlucast in 20 cases of cough variant asthma (CVA) and 20 cases of asthma. Placebo was used in 4 cases of CVA and 10 cases of asthma for comparison with the two therapy groups respectively. Before and after the zafirlucast treatment a series of parameters of DRC were obtained after the methacholine challenge test and were calculated. These included the response threshold (PC35sGaw), the dose-response slope (DRS), the ratio of the area under the curve to the logarithm of the maximal concentration (AUC/1 g[Cmax]), and the maximal response.

RESULTS

Zafirlucast significantly increased the PC35sGaw in the CVA and asthma groups. It conspicuously decreased all the parameters of DRS and AUC/1 g[Cmax] except for maximal response in the cases of CVA, and it had no significant effects on all the parameters of DRS and AUC/1 g[Cmax] except for PC35sGaw in the cases of asthma.

CONCLUSION

Short-term use of Zafirlucast in asthmatic patients could improve the parameters of dose-response curve obtained after the methacholine challenge test.

Effects of environmental and test conditions on VOC emissions from "wet" coating materials

In this paper, numerical simulations have been conducted to study the effects of key environmental and test conditions (air velocity, temperature, film thickness, and sample application time) on volatile organic compound (VOC) emissions from a "wet" coating material (wood stain). Simulation results indicate that air velocity and sample application time only significantly affect the emission profiles in the early stage. Film thickness, on the other hand, affects long-term emissions. Temperature can affect both the short-term and long-term emissions.

[Supercritical and near-critical fluid solvents assisted reaction and separation processes]

The tunability of supercritical and near-critical fluid (S/NCF) solvents offers environmental improvements and economic advantages from improved performances and flexibility for separation and reaction processes through density changes or cosolvents. The paper reviews the sustainable reaction and separation processes in S/NCF solvents such as supercritical carbon dioxide and near-critical water.

[Expression of vascular endothelial growth factor and nm23 as prognostic factors in nasopharyngeal carcinoma]

OBJECTIVE

To evaluate the prognostic significance of vascular endothelial growth factor (VEGF) and nm23 expression for patients with nasopharyngeal carcinoma(NPC).

METHODS

From Jan. 1991 to Dec. 1995, 75 NPC patients treated in Department of Radiotherapy & Chemotherapy, Zhongnan Hospital of Wuhan University, with follow-up of more than 4 yrs, were selected to enter this study. Specimens of 75 NPC were studied by immunohistochemical staining for VEGF and nm23. The immunohistochemical data were correlated with development of locoregional failure, distant metastasis and survival.

RESULTS

Positive expression of VEGF and negative expression of nm23 were found in 54.7% and 56% of NPC specimens. Positive expression of VEGF and negative expression of nm23 correlated with the development of distant metastasis (P = 0.0181; P = 0.0091) and shorter survival (P = 0.0136; P = 0.0207). No association was observed with locoregional failure. No association was observed between the expression of VEGF and the expression of nm23.Cox proportional hazard model was used to compare the various factors and found the VEGF and nm23 expression were significant prognostic factors for patients with NPC.

CONCLUSION

The results of the study show that the VEGF and nm23 expression are significant prognostic factors for patients with NPC and indicate that expression of VEGF and nm23 may be useful in identifying patients who may benefit from systemic chemotherapy or other novel treatment strategies.

[Measurement of the parameters of dose-response curve obtained after the methacholine challenge test]

OBJECTIVE

To investigate the clinical value in the measurement of parameters of the dose-response curve (DRC) obtained after the methacholine challenge test.

METHODS

Twenty-seven cases of cough variant asthma (CVA), 29 of mild asthma, 19 of moderate asthma, and 15 healthy volunteers underwent the methacholine challenge test. The dose-response curves were constructed. The following parameters were calculated: position (PC35sGaw), dose-response curve (DRS), ratio of the area under the curve to the logarithm of the maximal concentration (AUC/lg[Cmax]) and maximal response.

RESULTS

A plateau appeared in 11 cases among the healthy subjects, while a plateau appeared only in 2 cases of CVA and 2 of asthma. There were no significant differences among the asthmatic groups in the measurements of PC35sGaw and AUC/lg[Cmax] (geometric mean PC35sGaw: mild asthmatics = 0.369, moderate asthmatics = 0.251, cough variant asthmatics = 0.547), AUC/lg[Cmax] was significantly greater in the asthmatic groups than in the normal group [AUC/lg [Cmax](mean +/- s): mild asthmatics = 24.7 +/- 4.7, moderate asthmatics = 26.6 +/- 4.3, cough variant asthmatics = 25.6 +/- 3.7, normal subjects = 15.5 +/- 4.3, P < 0.01]. DRS of moderate asthmatics was significantly greater as compared with cough variant asthmatics (geometric mean DRS: mild asthmatics = 30.761, moderate asthma-tics = 59.020, cough variant asthmatics = 19.231, P < 0.05), but there was no difference between the other groups. PC35sGaw was negatively correlated with DRS (r = 0.866, P < 0.001) and with AUC/lg[Cmax] (r = 0.502, P < 0.001).

CONCLUSION

Four parameters of DRC obtained after the methacholine challenge represent airway sensitivity and reactivity respectively. The parameters of DRC of asthmatic patients are different from those of normal subjects. The sensitivity is related to the reactivity, but they are not completely parallel with each other.

Prostate biopsy protocols: 3D visualization-based evaluation and clinical correlation

OBJECTIVES

Systematic needle core biopsy is commonly used for the diagnosis of prostate cancer by urologists worldwide. As accurate and early diagnosis will result in more and better options for treatment, it is critical that the best possible protocols for biopsy be used clinically. In this study, we develop three-dimensional (3D) modeling and simulation technologies to evaluate most of the biopsy protocols in current clinical use, and correlate the results with those from clinical cases.

MATERIALS AND METHODS

Using deformable modeling techniques, 3D computerized prostate surface models were reconstructed from step-sectioned, whole-mounted radical prostatectomy specimens with localized prostate cancer. A 3D computer simulation system was developed to accurately depict the anatomy of the prostate and all individual tumor foci. A user-friendly interface was developed in the system so that a physician can easily and interactively use it for prostate needle core biopsy. A total of 281 prostate models were reconstructed, and 18 biopsies were performed by a urologist on each model to determine the detection rates of seven different biopsy protocols. Clinical biopsies from 35 patient cases were also reviewed and correlated with the simulation results.

RESULTS

The most commonly used sextant biopsy had only a 71.5% detection rate, while rates for the 10-pattern and 12-pattern protocols were much higher (96.4% and 97.2%, respectively). Even the lateral 4-pattern protocol performed better than the sextant protocol, with a detection rate of 89.3%. The lateral sextant biopsy protocol (using sites similar to, but more lateral than, those in the sextant protocol) achieved a rate of 92.5%. Although the rate of the 14-pattern biopsy was a little higher (97.5%), it used four more biopsies to achieve this increase, which, according to McNemar's test, is not statistically significant when compared to results with the 10-pattern protocol. The 5-region protocol, which uses 12 biopsies, had a detection rate of 89.7%. Transition zone and seminal vesicle biopsies did not result in a significantly increased detection rate when added to the patterns above. The clinical correlation also confirmed that the 10-pattern protocol was significantly superior to the traditional sextant biopsy pattern.

CONCLUSIONS

The 10-pattern biopsy protocol was the most optimized among all the protocols evaluated. This protocol supplemented the sextant biopsy protocol with four more lateral biopsies in the mid and apical sites on both sides.

[GC-MS analysis of supercritical carbon dioxide extraction products from pericarp of Zanthoxylum bungeanum]

The chemical constituents of supercritical carbon dioxide extraction products from pericarp of Zanthoxylum bungeanun Maxim. were studied by GC-MS-DS. Forty-five compounds which account for 86.76% of the area of the chromatographic peaks were identified. The results showed that the main components of the extracts are beta-pinene (10.33%), 1,8-terpinene (7.6%), cis-piperitol acetate (7.07%), oleic acid (5.46%), palmitic acid (5.41%) and 4-terpineol, (43.7%), et al.