Periodic mesoporous organosilicas with bis(8-quinolinolato) dioxomolybdenum(VI) inside the channel walls

Novel periodic mesostructured organometallic silicas of MCM-41 type bearing homogeneously distributed bis(8-quinolinolato)dioxomolybdenum(VI) inside the channel walls (denoted as MoO(2)Q(2)@PMO-x) are synthesized via a convenient one-pot method and examined as catalysts in the epoxidation of cyclooctene. The ordered mesoporous structures as well as the organometallic groups incorporated into the framework are fully determined by comprehensive characterization techniques such as XRD, TEM, N(2) adsorption/desorption, SEM, FT-IR, UV-vis spectroscopy, solid-state NMR, ICP-AES, XPS and TG/DSC. MoO(2)Q(2)@PMO-6% catalyst exhibits higher activity for the epoxidation of cyclooctene with tert-butyl hydroperoxide than other MoO(2)Q(2)@PMO materials and its homogeneous or randomly grafted analogue.

Transgene-mediated expression of tumor necrosis factor soluble receptor attenuates morphine tolerance in rats

Opiate/narcotic analgesics are the most effective treatments for chronic severe pain, but their clinical utility is often hampered by the development of analgesic tolerance. Recent evidence suggests chronic morphine may activate glial cells to release proinflammatory cytokines. In this study, we used herpes simplex virus (HSV) vectors-based gene transfer to dorsal root ganglion to produce a local release of p55 TNF soluble receptor in the spinal cord in rats with morphine tolerance. Subcutaneous inoculation of HSV vectors expressing p55 TNF soluble receptor into the plantar surface of the hindpaws, enhanced the antinociceptive effect of acute morphine in rats. Subcutaneous inoculation of those vectors into hindpaws also delayed the development of chronic morphine tolerance in rats. TNF soluble receptor expressed by HSV vector reduced gene transcription of mRNA of spinal TNFα and IL-1β induced by repeated morphine. Furthermore, we found that TNF soluble receptor mediated by HSV, reversed the upregulation of TNFα, IL-1β and phosphorylation of p38 mitogen-activated protein kinase (MAPK) induced by repeated morphine. These results support the concept that proinflammatory cytokines may play an important role in the pathogenesis induced by morphine. This study provides a novel approach to treating morphine tolerance.

[Spine disc MR image analysis using improved independent component analysis based active appearance model and Markov random field]

As there are not many research reports on segmentation and quantitative analysis of soft tissues in lumbar medical images, this paper presents an algorithm for segmenting and quantitatively analyzing discs in lumbar Magnetic Resonance Imaging (MRI). Vertebrae are first segmented using improved Independent component analysis based active appearance model (ICA-AAM), and lumbar curve is obtained with Minimum Description Length (MDL); based on these results, fast and unsupervised Markov Random Field (MRF) disc segmentation combining disc imaging features and intensity profile is further achieved; finally, disc herniation is quantitatively evaluated. The experiment proves that the proposed algorithm is fast and effective, thus providing doctors with aid in diagnosing and curing lumbar disc herniation.

Hot flashes are associated with CYP2D6 genotype in breast cancer survivors taking tamoxifen

Abstract #6045

Background: We have previously shown that participants in the Women's Healthy Eating and Living (WHEL) study comparison group who reported hot flashes after breast cancer treatment had more favorable disease-free survival than women who did not report hot flashes. However, this was not the case in the intervention group. The polymorphic CYP450 enzyme CYP2D6 catalyzes the conversion of tamoxifen (TAM) to one of its key active metabolites, endoxifen. Some studies have suggested that certain genetic variants of CYP2D6 are associated with a decreased likelihood of hot flashes, reduced endoxifen levels and an increased risk of disease recurrence in women receiving adjuvant TAM therapy. This analysis was performed to estimate the association between CYP2D6 genotype and hot flashes in early stage breast cancer survivors who took adjuvant TAM in the WHEL study.
 Methods: The WHEL study was a randomized trial of a dietary intervention in breast cancer survivors, who enrolled in the study within 4 years of diagnosis from 1995-2000. Participants self-reported TAM use, hot flash severity and menopausal status at study entry. Clinical characteristics (tumor stage, estrogen receptor status, chemotherapy) were extracted from medical records. Blood samples were obtained by venipuncture, separated and stored at -80 deg. DNA was extracted from stored buffy coat and analyzed using the Roche AmpliChip CYP450 Test. Women were classified according to their predicted CYP2D6 phenotype as Extensive (EM), Heterozygous Extensive (Het EM), Intermediate (IM), Poor (PM), or Ultrarapid (UM) Metabolizers.
 Results: Overall, 1434 WHEL participants had verified estrogen receptor-positive stage I or II breast cancers and reported taking TAM at baseline for at least 4 months. A total of 1411 women were successfully genotyped and their CYP2D6 phenotypes were classified as follows: 468 EM (33.2%); 665 Het EM(47.1%), 164 IM (11.6%), 86 PM (6.1%) and 28 UM (2.0%). In univariate analyses, there was a significant difference among CYP2D6 genotype in relation to hot flashes reported at baseline: 79.8% of EMs, 76.3% of Het EMs, 80.1% of IMs, 63.9% of PMs, and 75% of UMs reported hot flashes (χ2= 11.3, p=0.02). After controlling for age, menopausal status, and time since diagnosis, the PM group was half as likely to report hot flashes as the referent EM group (OR= 0.46; 95% CI= 0.28-0.78; p=0.003). Additional analyses of serum endoxifen levels and associations with disease outcome are underway.
 Conclusion: In the WHEL study, women who were classified as Poor Metabolizers of TAM, based on their CYP2D6 genotype, were half as likely as Extensive Metabolizers to report experiencing hot flashes while receiving adjuvant TAM treatment for early stage breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6045.

HSV-mediated transfer of interleukin-10 reduces inflammatory pain through modulation of membrane tumor necrosis factor alpha in spinal cord microglia

To dissect the molecular basis of the neuroimmune response associated with the genesis of inflammatory (nociceptive) pain, we constructed a herpes simplex virus-based gene transfer vector to express the antiinflammatory cytokine interleukin-10 (IL-10), and used it to examine the effect of IL-10 expression in activated microglial cells in vitro, and in inflammatory pain in vivo. IL-10 reduced the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and decreased the expression of full-length membrane spanning tumor necrosis factor-alpha (mTNFalpha) following lipopolysaccharide stimulation of microglia in vitro. IL-10 also reduced intracellular cleavage of mTNFalpha and release of the soluble cleavage product sTNFalpha. Similar effects on TNFalpha expression were observed when the cells were pretreated with a p38 MAPK inhibitor. In animals, injection of a dilute solution of formalin in the skin resulted in an increase in mTNFalpha in spinal dorsal horn, without detectable sTNFalpha. Local release of IL-10 achieved by gene transfer reduced the number of spontaneous flinches in the early and delayed phases of the formalin test of inflammatory pain. The effect of IL-10 on nocisponsive behavior correlated with a block in phosphorylation of p38 and reduced expression of 26 kDa mTNFalpha in spinal microglia. The results emphasize the key role played by membrane TNFalpha in the spinal neuroimmune response in pain caused by peripheral inflammation.

Gene transfer to interfere with TNFalpha signaling in neuropathic pain

We examined the role of spinal tumor necrosis factor-alpha (TNFalpha) in neuropathic pain of peripheral nerve origin. Two weeks after selective L5 spinal nerve ligation (SNL), rats exhibiting mechanical allodynia and thermal hyperalgesia showed a marked increase in full-length membrane-associated TNFalpha (mTNFalpha) in the dorsal horn of spinal cord, in the absence of detectable soluble TNFalpha peptide. Local release of the soluble p55 TNF receptor, achieved by herpes simplex virus vector-based gene transfer to dorsal root ganglion, resulted in a reduction of mTNFalpha and concomitant reductions in interleukin-1beta and phosphorylated p38 MAP kinase. Subcutaneous inoculation of soluble p55 TNF receptor expressing HSV vector into the plantar surface of the hind foot ipsilateral to the ligation 1 week before SNL delayed the development of both mechanical allodynia and thermal hyperalgesia; subcutaneous inoculation into the hind foot ipsilateral to the ligation 1 week after SNL resulted in a statistically significant reduction in mechanical allodynia and thermal hyperalgesia that was apparent 1 week after inoculation. These results suggest a novel 'reverse signaling' through glial mTNFalpha, which may be exploited to downregulate the neuroimmune reaction in spinal cord to reduce chronic neuropathic pain.

Enhanced T-cell immunity induced by dendritic cells with phagocytosis of heat shock protein 70 gene-transfected tumor cells in early phase of apoptosis

The dual role of heat shock protein 70 (HSP70), as antigenic peptide chaperone and danger signal, makes it especially important in dendritic cell (DC)-based vaccination. In this study, we investigated the impacts of apoptotic transgenic MCA/HSP tumor cells expressing HSP70 on DC maturation, T-cell stimulation and vaccine efficacy. We found that DCs with phagocytosis of MCA/HSP in early phase of apoptosis expressed more pMHC I complexes, stimulated stronger cytotoxic T lymphocyte (CTL) responses (40% specific killing at an E:T cell ratio of 50) and induced immune protection in 90% of mice against MCA tumor cell challenge, compared with 25% specific CTL killing activity and 60% immune protection seen in mice immunized with DC with phagocytosis of MCA/HSP in late phase of apoptosis (P<0.05). Similar results were confirmed in another EG7 tumor model also expressing HSP70. Taken together, our data demonstrate that HSP70 on apoptotic tumor cells stimulate DC maturation, and DC with phagocytosis of apoptotic tumor cells expressing HSP70 in early phase of apoptosis more efficiently induced tumor-specific CTL responses and immunity than DCs with phagocytosis of apoptotic tumor cells in late phase of apoptosis. These results may have an important impact in designing DC-based antitumor vaccines.

Mobilized retrotransposon Tos17 of rice by alien DNA introgression transposes into genes and causes structural and methylation alterations of a flanking genomic region

Tos17 is a copia-like endogenous retrotransposon of rice, which can be activated by various stresses such as tissue culture and alien DNA introgression. To confirm element mobilization by introgression and to study possible structural and epigenetic effects of Tos17 insertion on its target sequences, we isolated all flanking regions of Tos17 in an introgressed rice line (Tong35) that contains minute amount of genomic DNA from wild rice (Zizania latifolia). It was found that there has been apparent but limited mobilization of Tos17 in this introgression line, as being reflected by increased but stable copy number of the element in progeny of the line. Three of the five activated copies of the element have transposed into genes. Based on sequence analysis and Southern blot hybridization with several double-enzyme digests, no structural change in Tos17 could be inferred in the introgression line. Cytosine methylation status at all seven CCGG sites within Tos17 was also identical between the introgression line and its rice parent (Matsumae)-all sites being heavily methylated. In contrast, changes in structure and cytosine methylation patterns were detected in one of the three low-copy genomic regions that flank newly transposed Tos17, and all changes are stably inherited through selfed generations.

Epigenetic transfer of metastatic activity by uptake of highly metastatic B16 melanoma cell-released exosomes

AIM

To investigate potential role of highly metastatic BL6-10 tumor cell-released exosomes (EXO) in transfer of metastatic activity into poorly metastatic tumor cell line F1.

METHODS

The highly metastatic B16 melanoma cell line (BL6-10) was generated in our laboratory. EXO from this cell line were isolated and amount of exosomal recovered proteins was measured using Bradford assay. For phenotypic analysis BL6-10 and F1 melanoma cells were stained with FITC-conjugated anti-MHC I (H-2K(b)), MHC II (Ia(b)) and Met 72 antibodies and analyzed by flow cytometry. C57BL/6 mice (8 per group) were injected (i. v.) with 0.5 x 10(6) F1, BL6-10 and F1(EXO) melanoma cells. Lungs were removed 4 weeks after tumor cell injection, fixed in 10% neutral buffered formaldehyde and embedded in paraffin for histological analysis.

RESULTS

Data revealed that BL6-10 cells expressed metastasis marker (Met 72 tumor antigen), while F1 cells did not display this cell surface marker. All mice inoculated with BL6-10 melanoma cells had numerous lung tumor colonies, while mice injected with F1 tumor cells were free of lung metastatic colonies. BL6-10 tumor cells-released EXO also expressed Met 72 tumor antigen as BL6-10 tumor cells, but in less amount. F1 tumor cells can uptake EXO from BL6-10 tumor cells and express acquired exosomal Met 72 tumor antigen.

CONCLUSION

The metastatic activity of highly metastatic BL6-10 tumor cells can be transferred to poorly metastatic F1 tumor cells by uptake of highly metastatic BL6-10 tumor-released EXO.

Activation of a rice endogenous retrotransposon Tos17 in tissue culture is accompanied by cytosine demethylation and causes heritable alteration in methylation pattern of flanking genomic regions

Tos17 is a copia-like, cryptic retrotransposon of rice, but can be activated by tissue culture. To study possible epigenetic mechanism controlling activity of Tos17, we subjected three rice lines (the parental line cv. Matsumae and two introgression lines, RZ2 and RZ35) that harbor different copies of the element to tissue culture. For each line, we investigated transcription and transposition of Tos17 in seed plants, calli and regenerated plants, cytosine-methylation status at CG and CNG positions within Tos17, effect of 5-azacytidine on methylation status and activity of Tos17, and cytosine-methylation states in genomic regions flanking original and some newly transposed copies of Tos17 in calli and regenerated plants. We found that only in introgression line RZ35 was Tos17 transcriptionally activated and temporarily mobilized by tissue culture, which was followed by repression before or upon plant regeneration. The activity and inactivity of Tos17 in calli and regenerated plants of RZ35 are accompanied by hypo- and hyper-CG methylation and hemi- and full CNG methylation, respectively, within the element, whereas immobilization of the element in the other two lines is concomitant with near-constant, full hypermethylation. Treatment with 5-azacytidine induced both CG and CNG partial hypomethylation of Tos17 in two lines (Matsumae and RZ35), which, however, was not accompanied by activation of Tos17 in any line. Heritable alteration in cytosine-methylation patterns occurred in three of seven genomic regions flanking Tos17 in calli and regenerated plants of RZ35, but in none of the five regions flanking dormant Tos17 in the other two lines.

Molecular cytogenetic characterization of a familial balanced reciprocal translocation t(11;18) (q13.3; q23) associated with pregnancy wastage

A new male patient associated with a pregnancy wastage was detected in China. Cytogenetic analyses including G-banding, chromosome painting and observation of synaptonemal complexes (SCs) demonstrated that the pregnancy wastage was associated with a balanced reciprocal translocation t(11;18) (q13.3; q23). The proband was the carrier of the translocation and his karyotype was 46,XY,t(11;18)(11pter-->11q13.3:: 18q23-->18qter; 18pter-->18q23::11q13.3-->11qter). The pedigree was analyzed based on a G-banded karyotype of the nine familial members. The translocation chromosomes came from the proband's mother. The result of the SC observation in the proband showed that each of the spermatocytes displayed one quadrivalent during their pachytene stages. In the quadrivalents, there existed homologous and nonhomologous synapses and the latter occurred widely during early, middle and late pachytene stages. The reasons and genetic basis of the pregnancy wastage are discussed.

Distribution and transcription activity of nucleolar DNA in higher plant cells

By using the NAMA-Ur DNA selective staining method, we have observed in situ the location of nucleolar DNA in onion cells and found it at the boundary between fibrillar centres (FC) and dense fibrillar component (DFC) in transcriptionally active nucleolus. We have also used anti-NOR serum, which is identified as the RNA Polymerase I transcription factor (UBF) antibody, to study its reactivity with higher plant cells and demonstrated this factor associated to the DFC but not present at the interior of FC. Finally, by employing anti-DNA/RNA hybrid antibodies, we labeled the transcriptionally active rRNA genes in active nucleolus and testified that at the boundary between FC and DFC. The results provide the evidence that the boundary between FC and DFC is the genuine transcription site of rRNA genes in nucleolus.

Diet restriction in mice causes a decrease in hippocampal choline uptake and muscarinic receptors that is restored by administration of tyrosine: interaction between cholinergic and adrenergic receptors influencing cognitive function

We have studied the effects of diet restriction (DR) to 60% and 40% of daily requirements, and tyrosine administration on cognitive function in mice, to define the nutritional-neurochemical interactions on autonomic tone involved in behavior and energy regulation. Cognitive function in the Morris Water maze was significantly impaired after 40% DR compared to both control and 60% DR. It was restored after tyrosine in association with increased M1 cholinergic and beta-adrenergic receptor function, and decreased alpha-adrenergic function. DR to 40% significantly decreased choline uptake (p <.05) and M1 receptor number (Bmax) (p <.05), without changes in affinity (Kd), choline acetyl transferase (ChAT) or acetyl cholinesterase (AChE) activity. Tyrosine administration significantly increased choline uptake (Bmax) (p <.05) and M1 density in the 40% DR (p <.01) without changes in affinity. ChAT activity was decreased after tyrosine--significantly after 40% DR (p <.05) while AChE was not affected. Both M1 mRNA and protein were not influenced by DR or tyrosine administration. Tyrosine hydroxylase mRNA was decreased significantly by 40% DR (p <.01). The effect of DR and tyrosine appeared to be both pre- and post-synaptic, indicating modulation of cholinergic activity by adrenergic tone. Nutritional effect on behavior and autonomic tone may have implications for the treatment of mood changes associated with weight loss and semi-starvation.

Tyrosine improves appetite, cognition, and exercise tolerance in activity anorexia

PURPOSE

We have modified for mice the activity wheel model of Routtenberg to study the effects of tyrosine on exercise tolerance, behavior, and brain neurochemistry.

METHODS

Mice were fed for 2 h.d(-1) over a 2-wk period. During the second week, each group was injected daily with either saline or tyrosine (100 mg.kg(-1).d(-1)) and exercised on a running wheel. Controls were in cages with inactivated wheels and received the same treatment and feeding protocols as the experimental groups. Food consumption and cognitive function (eight-arm maze) were evaluated for 1 wk. Brains were then assayed for adrenergic and serotonergic metabolites.

RESULTS

Activity together with a restricted diet caused extreme weight loss (27%) (P < 0.001) together with decreased food consumption (22%) (P < 0.001). Tyrosine restored food consumption to that of the controls (P < 0.001) with no effect on weight, since there was a 22% increase in activity (P < 0.001). Saline injections caused an 18% decrease in activity (P < 0.001). Both activity and tyrosine improved maze performance (P < 0.05). In the hypothalamus, activity caused a significant increase in 5-hydroxytryptamine (5-HT) (P < 0.001), 5-hydroxyindoleacetic acid (5-HIAA) (P < 0.01), and dopamine (P < 0.05); tyrosine prevented the increase in 5-HT (P < 0.05) and increased 5-HIAA in the controls (P < 0.01). With regard to hippocampal 5-HT, there was a significant increase in 5-HIAA following activity (P < 0.05), whereas tyrosine caused significant increase in 5-HIAA in the controls (P < 0.01). Activity significantly decreased the level of hippocampal 3,4-dihydroxyphenylacetic acid (DOPAC), whereas tyrosine decreased its level only in the controls (both at P < 0.0001). The level of tyrosine hydroxylase increased with activity (P < 0.05), and tyrosine decreased it significantly (P < 0.05).

CONCLUSION

Activity anorexia is associated with increased hypothalamic 5-HT concentrations. Tyrosine administration reverses this, and significantly improves food consumption, cognitive behavior, and activity performance. Such nutritional modulations may have implications for the treatment of eating disorders and, in normal circumstances, tyrosine may improve exercise tolerance and delay fatigue.

[Study on the form and stability of alpha and beta domain of metallothionein binding to lead (II)]

For studying the actions of metallothionein(MT) binding to lead, the alpha and beta structural domain of metallothionein binding to Cd (Cd7-alpha-MT and Cd7-beta-MT) was extracted and purified from a strain of BL2I by dissolving them in acid to eliminate protein. The apo-alpha-MT and apo-beta-MT were separated by gel Sephadex-G25 to eliminate Cd. Different doses of lead were added to the apo-alpha-MT and apo-beta-MT. The structure of MT metal Cluster with lead was formed after reacting completely, and was then examined by ultraviolet spectrophotometer. The UV spectrum showed that the interaction of lead with alpha domain leading to two kind of products, one binding with 4 lead(Pb4-alpha-MT) and the other binding with 7 lead (Pb7-alpha-MT). Only one product, the beta domain binding with 3 lead(Pb3-beta-MT) was formed. The reaction rate of these products with DTNB was also measured in this study. Results showed that the domain binding to 4 lead was more stable than the others. All these works provide strong evidence that further studies on the mechanism of MT interacting with lead and the function of MT in eliminating lead were needed.

The role of zinc binding in the biological activity of botulinum toxin

Botulinum toxin is a zinc-dependent endoprotease that acts on vulnerable cells to cleave polypeptides that are essential for exocytosis. To exert this poisoning effect, the toxin must proceed through a complex sequence of events that involves binding, productive internalization, and intracellular expression of catalytic activity. Results presented in this study show that soluble chelators rapidly strip Zn(2+) from its binding site in botulinum toxin, and this stripping of cation results in the loss of catalytic activity in cell-free or broken cell preparations. Stripped toxin is still active against intact neuromuscular junctions, presumably because internalized toxin binds cytosolic Zn(2+). In contrast to soluble chelators, immobilized chelators have no effect on bound Zn(2+), nor do they alter toxin activity. The latter finding is because of the fact that the spontaneous loss of Zn(2+) from its coordination site in botulinum toxin is relatively slow. When exogenous Zn(2+) is added to toxin that has been stripped by soluble chelators, the molecule rebinds cation and regains catalytic and neuromuscular blocking activity. Exogenous Zn(2+) can restore toxin activity either when the toxin is free in solution on the cell exterior or when it has been internalized and is in the cytosol. The fact that stripped toxin can reach the cytosol means that the loss of bound Zn(2+) does not produce conformational changes that block internalization. Similarly, the fact that stripped toxin in the cytosol can be reactivated by ambient Zn(2+) or exogenous Zn(2+) means that productive internalization does not produce conformational changes that block rebinding of cation.

Antinociceptive interaction between spinal clonidine and lidocaine in the rat formalin test: an isobolographic analysis

Clinical and basic science studies suggest that spinal alpha-2-adrenergic receptor agonists and local anesthetics produce analgesia, but interaction between alpha-2-adrenergic receptor agonists and local anesthetics in the persistent pain model has not been examined. In the present study, using isobolographic analysis, we investigated the antinociceptive interaction of intrathecal clonidine and lidocaine in the rat formalin test. Sprague-Dawley rats were implanted with chronic lumbar intrathecal catheters, and were tested for paw flinch by formalin injection. Biphasic painful behavior was counted. Intrathecal clonidine (3-12 nmol) was administered 15 min before formalin, and intrathecal lidocaine (375-1850 nmol) was administered 5 min before formalin. To examine the interaction of intrathecal clonidine and lidocaine, an isobolographic design was used. Spinal administration of clonidine produced dose-dependent suppression of the biphasic responses in the formalin test. Spinal lidocaine resulted in dose-dependent transient motor dysfunction and the motor dysfunction recovered to normal at 10-15 min after administration. Spinal lidocaine produced dose-dependent suppression of phase-2 activity in the formalin test. Isobolographic analysis showed that the combination of intrathecal clonidine and lidocaine synergistically reduced Phase-2 activity. We conclude that intrathecal clonidine synergistically interacts with lidocaine in reducing the nociceptive response in the formalin test.

IMPLICATIONS

Preformalin administration of intrathecal clonidine and lidocaine dose-dependently produced antinociception in the formalin test. The combination of clonidine and lidocaine, synergistically produced suppression of nociceptive response in the persistent pain model.

Structural components of the nuclear body in nuclei of Allium cepa cells

Nuclear bodies have long been noted in interphase nuclei of plant cells, but their structural component, origin and function are still unclear by now. The present work showed in onion cells the nuclear bodies appeared as a spherical structure about 0.3 to 0.8 microm in diameter. They possibly were formed in nucleolus and subsequently released, and entered into nucleoplasm. Observation through cytochemical staining method at the ultrastructural level confirmed that nuclear bodies consisted of ribonucleoproteins (RNPs) and silver-stainable proteins. Immunocytochemical results revealed that nuclear bodies contained no DNA and ribosomal gene transcription factor (UBF). Based on these data, we suggested that nuclear bodies are not related to the ribosome or other gene transcription activities, instead they may act as subnuclear structures for RNPs transport from nucleolus to cytoplasm, and may also be involved in splicing of pre-mRNAs.

Separation-induced body weight loss, impairment in alternation behavior, and autonomic tone: effects of tyrosine

We have investigated the effects of tyrosine on alternation behavior and hippocampal adrenergic and cholinergic tone in a model of self-induced weight loss caused by separation stress. Separation decreased body weight in mice (P < .001) and spontaneous alternations in the T-maze (P < .001). This impairment was associated with depletion of both norepinephrine (NE, P < .001) and dopamine (P < .01) while increasing MHPG (P < .05) and the ratio of MHPG/NE (P < .05). Increasing tyrosine availability restored performance to control levels (P < .001) and repleted dopamine (P < .05) and presumably also NE (indicated by increases in both MHPG, P < .001, and MHPG/NE, P < .05). Stress increased adrenergic alpha(2)-receptor density (P < .001) without changing its K(d) and the B(max) and K(d) of beta-receptors, suggesting that it decreased NE transmission through action on alpha(2)-receptors. The balance between beta- and alpha(2)-receptors appeared to be related to alternation behavior as shown by the decrease (P < .01) and increase (P < .05) in their ratios induced by stress and tyrosine, respectively. With regard to cholinergic tone, separation stress increased M1 receptor density (P < .05) and its mRNA signal (P < .001). Tyrosine further increased M1 receptor density of stressed mice (P < .05). Tyrosine might be a potential therapy for cognitive and mood problems associated with the maintenance of a reduced body weight in the treatment of obesity and in the extreme case of anorexia nervosa.

Electroacupuncture potentiates the antinociceptive effect of intrathecal endomorphin-1 in the rat formalin test

Endomorphin-1 is a novel endogenous mu-opioid peptide. In this study, we examined the effects of 2 Hz electroacupuncture in the rat tail flick test and the formalin test (a persistent noxious model). Moreover, we investigated if the electroacupuncture potentiated the effect of intrathecal endomorphin-1. The results demonstrated that electroacupuncture alone produced a significant antinociception in the tail flick test, but not in the formalin test, and that intrathecal endomorphin-1 dose-dependently suppressed the biphasic nociceptive behavior in the formalin test. Electroacupuncture enhanced the antinociceptive effect of intrathecal endomorphin-1 in the formalin test, resulting in a significant leftward shift in the dose-response curves for intrathecal endomorphin-1 antinociception. The enhanced effect was antagonized by intraperitoneal naltrexone. The study suggests that electroacupuncture may potentiate the intrathecal endomorphin-1 antinociception partially mediated by opioid receptors.

Structures of nucleolus and transcription sites of rRNA genes in rat liver cells

We observed the ultrastructure of nucleolus in rat liver cells by conventional electron microscopy, and employed cytochemistry NAMA-Ur DNA specific stain method to analyze the distribution and position of nucleolar DNAin situ. The results showed that nucleolar DNA of rat liver cells comes from nucleolus-associated chromatin, and continuously extends in the dense fibrillar component (DFC) of nucleolus, localizes at the periphery of fibrillar center (FC) and in DFC. Furthermore, by employing anti-DNA/RNA hybrid antibodies, we directly and selectively labeled transcription sites of rRNA genes and testified that localization of transcription sites not only to DFC but also to the periphery of FC.

[An observation of the immuno-persistence after inoculating with the domestic BRD II strain rubella vaccine among infants and young children]

OBJECTIVE

To study the immuno-persistence after inoculating with the domestic BRD II strain rubella vaccine among infants and young children.

METHODS

Hemagglutination inhibition (HI) antibody detection method was used to test on children at age 6 to 18 months without rubella infection or rubella vaccine immunization in Yantai city of Shandong province and were selected for the observation of the immuno-persistence against the domestic BRD II strain rubella vaccine from 1995 to 1998.

RESULTS

Positive rates of HI antibody among children of 6, 7, 8, 9, 12 and 18 month-old of inoculation were 94.44%, 97.22%, 96.67%, 100.00%, 100.00%, 100.00% and 93.10%, 93.55%, 96.77%, 96.97%, 100.00%, 100.00% (P > 0.05), in one or two years respectively. The geometric mean reverse titers (GMRTs) were about 50% lower than that after 1 month after 1 year. Similar results were found that after 2 years GMRTs was about 50% lower than that after 1 year of inoculation. There was highly significant difference on GMRTs of HI antibody between infants with 6 to 7 month-olds (29.89) and young children with 8 to 18 month-olds (53.00) after 2 years of inoculation (t = 3.58, P < 0.001).

CONCLUSION

The immunization schedule at the first dose for BRD II strain rubella vaccine should be started when the child is 8 month old. For the second dose, the immunization schedule used in other developed countries should be referred adopted in China.

Low dose anandamide affects food intake, cognitive function, neurotransmitter and corticosterone levels in diet-restricted mice

This investigation reports the possible role of the endocannabinoid anandamide on modulating the behavioral and neurochemical consequences of semi-starvation. We studied the effect of very low dose anandamide (0.001 mg/kg) administration on food intake, cognitive function and catecholaminergic and serotonergic pathways in two murine brain areas concerned with appetite (hypothalamus) and learning (hippocampus), and the peripheral corticosterone response to the stress of 40% diet restriction. Anandamide-treated mice consumed 44% more food (P<0.05) during 1 week of 2.5-h feeding each day. In the hypothalamus, there were significantly increased concentrations of norepinephrine (P<0.01), dopamine (P<0.05) and 5-hydroxytryptamine (5-HT) (P<0.001). In the hippocampus, anandamide increased significantly norepinephrine and dopamine, but decreased 5-HT (all at P<0.001). Diet restriction was accompanied in both areas by a significant decrease in all neurotransmitter concentrations that were partially restored by anandamide for dopamine and 5-HT, but not for norepinephrine. In animals on diet restriction, anandamide significantly improved impaired maze performance. Norepinephrine turnover and plasma corticosterone levels were also raised significantly by anandamide. The fact that low dose anandamide improved food intake, cognitive function and reversed some of the neurotransmitter changes caused by diet restriction, might have implications for the treatment of cachexia associated with acquired immunodeficiency syndrome (AIDS) and cancer, for mood changes sometimes associated with dieting, and in the extreme case, of patients with anorexia.

[Study on the absorption of environmental contaminants in low-level exposure by pharmacokinetic analysis]

A dynamic generating toxic gas system and a nose-only exposure system were used for the pharmacokinetic study of inhaled environmental contaminants for benzene, toluene, xylene, ethylbenzene, chlorobenzene, styrene, isopropyl benzene, tetrachloroethylene, nonane and methylcyclohexane in male guinea pig. The change of these substances in blood with time was determined simultaneously by solid phase micro-extraction(SPME) gas chromatography (GC). The results showed that the fraction of absorption of benzene at low (121 micrograms/m3) exposure was 4.8 times higher than that at high(12.1 mg/m3) exposure. The pharmacokinetics of these substances were evaluated by using linear compartment models. The data showed that more styrene was absorbed than tetrachloroethylene at low-exposure. The metabolic elimination of these compounds at various exposure concentrations was extrapolated by using estimated pharmacokinetic parameters. Moreover, not only should the differences in absorption quantities be considered in evaluation of potential risk assessment, the metabolic elimination rates should also be considered although the exposure concentrations in gas for all chemicals were equal. The data presented in this paper was fundamental data used for risk assessment.

Intrathecal endomorphin-1 produces antinociceptive activities modulated by alpha 2-adrenoceptors in the rat tail flick, tail pressure and formalin tests

It is known that spinal morphine produces antinociception that is modulated by alpha 2-adrenoceptors. Endomorphin-1, a newly-isolated endogenous opioid ligand, shows the greatest selectivity and affinity for the mu-opiate receptor of any endogenous substance found to date and may serve as a natural ligand for the mu-opiate receptor. We examined the antinociceptive effects of endomorphin-1 administered intrathecally (i.t.) in the rat tail flick, tail pressure and formalin tests. Intrathecal endomorphin-1 produced dose-dependent antinociceptive effects in the three tests. ED50 (CI95) values for antinociception of i.t. endomorphin-1 in the tail flick test and tail pressure test were 1.9 (0.96-3.76) nmol and 1.8 (0.8-4.2) nmol, respectively. ED50 (CI95) values for phase 1 and phase 2 in the formalin test were 12.5 (7.9-19.8) nmol and 17.5 (10.2-30) nmol, respectively. Pretreatment with i.t. beta-funaltrexamine (a mu-opioid receptor selective antagonist) significantly antagonized the antinociceptive effects of endomorphin-1 in the three tests. Beta-funaltrexamine alone had not effects on the three tests. The antinociceptive effects of endomorphin-1 were also antagonized by i.t. yohimbine (an alpha 2-adrenoceptor selective antagonist). The combination of ineffective doses of i.t. clonidine (an alpha 2-adrenoceptor agonist) and endomorphin-1 produced a significant antinociception in the three tests. The results showed that intrathecal endomorphin-1 produced antinociception in a dose-dependent manner in the rat tail flick, tail pressure and formalin tests, which was mediated by spinal mu-opioid receptors and modulated by alpha 2-adrenoceptors.

[Vertical distribution and quantitative dynamics of dominant functional groups of arthropod community in rice fields and estimation of natural enemy effects]

The study showed that Lycosid (wolf spider) mainly distributed in the basal part of rice plants, not as wide as we know in past. Tetragnathid did not limited in the upper part of plants, but might translate to middle or lower part when affected by insecticide. The relationship between the vertical distributions of top and basal species was not significant. Besides the amount of natural enemies, the spatial distribution characteristics of natural enemies and brownplanthopper, and the proportion of brownplanthopper to total preys of natural enemies were the factors affecting the role of natural enemies on the population dynamics of brownplanthopper in rice fields. A model to evaluate the effect of natural enemies to brownplanthopper was put forward, which included the message of quantitative dynamics, spatial distribution and feeding characteristics of natural enemies, brownplanthopper and neutral insects.

[Determination of volatile organic compounds in blood by headspace solid-phase microextraction-gas chromatography]

The headspace solid-phase microextraction (HS-SPME) is a novel extraction technique and has been developed rapidly. It is a fast, simple, solventless and sensitive method for sampling, separating, extracting, injecting and analyzing volatile organic compounds. This paper presents the research work in detecting volatile organic compounds(including ten compounds) in blood. The extraction fiber is made by fused-silica fiber with 100 microns polydimethylsiloxane (PDMS). The extraction time of the method was 10 min. The thermal desorption time was 1 min. It was found that the optimized location of the extraction fiber in the injector of GC was to put the whole needle in the injector. The precision of the method was determined to be less 5% relative standard deviation (RSD). The linear range of the detection was rather wide. The lowest detectin limits (LODs) were all < or = 5 ng/ml.

Isobolographic analysis of interaction between spinal endomorphin-1, a newly isolated endogenous opioid peptide, and lidocaine in the rat formalin test

Endomorphin-1, a newly isolated endogenous opioid ligand, has a potential affinity with mu-opioid receptor. We investigated antinociception of intrathecal endomorphin-1 and lidocaine in the rat formalin test and examined the interaction between the two agents using isobolographic analysis. Intrathecal endomorphin-1 caused dose-dependent suppression of the formalin-induced biphasic behavioral response. Intrathecal lidocaine produced dose-dependent inhibition of phase-2 behavioral response. Isobolographic analysis confirmed that combination of intrathecal endomorphin-1 and lidocaine, given at a fixed dose ratio, produced synergistic suppression of phase-2 behavioral response. These data demonstrate that spinal endomorphin-1 synergistically interacts with local anesthetic lidocaine in producing antinociception in the formalin test.

[Immunocytochemical identification of tropomyosin in nucleoli and nucleolar matrix of Physarum polycephalum]

Nucleoli were isolated from physarum polycephalum, and nucleolar matrix was prepared by digesting the nucleoli respectively with DNase 1, 0.25 mol/L (NH4)2SO4 and 2 mol/L NaCl to remove DNA and most proteins. SDS-PAGE analysis indicated that there were about 20 polypeptides in nucleolar matrix component, including the 37 kD polypeptide which was similar to tropomyosin in molecular weight. The result of indirect immunofluorescence treated with anti-tropomyosin antibody and sheep anti-rabbit IgG antibody labelled with FITC showed that bright fluorescence was observed in the nucleoli and nucleolar matrix, but no bright fluorescence in the controls. Indirect Immunoblotting detection further verified that tropomyosin existed in nucleolar matrix. Protein A-colloidal gold immunoelectron microscopic study showed that there were many gold particles in the specimens labelled with tropomyosin antibody, and there were few gold particles found in the controls. Tropomyosin distributed dispersedly in nucleoli.

[Direct and indirect somatic embryogenesis in Freesia refracta]

Somatic embryogenesis can be induced in tissue cultures of Freesia refracta either directly from the epidermal cells of explant, or indirectly via intervening callus. In direct pathway, somatic embryos were in contact with maternal tissue in a suspensor-like structure. In indirect pathway, the explants first proliferacted to give rise to calluses before embryoids were induced. The two sorts of calluses were defined to embryogenic callus and non-embryogenic callus according to producing of somatic embryos. An indirect somatic embryo is developed from a pre-embryogenically determined cell. This kind of somatic embryo has no suspensor structure instead of a complex with maternal tissue. Somatic embryos have their own vascular tissues, and can develop new plantlets independently.

Tropomyosin is localized in the nuclear matrix and chromosome scaffold of Physarum polycephalum

The nuclei and chromosomes were isolated from plasmodia of Physarum polycephalum. The nuclear matrix and chromosome scaffold were obtained after the DNA and most of the proteins were extracted with DNase I and 2 M NaCl. SDS-PAGE analyses revealed that the nuclear matrix and chromosome scaffold contained a 37 kD polypeptide which is equivalent to tropomyosin in molecular weight. Immunofluorescence observations upon slide preparations labeled with anti-tropomyosin antibody showed that the nuclear matrix and chromosome scaffold emanated bright fluorescence, suggesting the presence of the antigen in them. Immunodotting results confirmed the presence of tropomyosin in the nuclear matrix and chromosome scaffold. Immunoelectron microscopic observations further demonstrated that tropomyosin was dispersively distributed in the interphase nuclei and metaphase chromosomes.

[Effect of rodents on reforestation in the moumtain regions near Beijing]

From 1993 until 1995, the influence of rodents on reforestation in the mountain regions near Beijing was studied in order to estimate the pressure of rodents on the seed supply, search for effective ways to decrease the loss of seeds due to consumption by rodents, and increase seed germinating power. It was shown that acorns, apricot pits and nuts are almost entirely carried away from the soil surface by rodents, thus suggesting that rodents have a great impact on the seed supply. When the seeds were sowed at a depth of about 5 cm, many of them were not eaten by rodents; 39% of acrons and 18% of apricot pits germinated on the following year. We propose that deep sowing of seeds may effectively decrease the loss of seeds through consumption by rodents.

Sevoflurane suppresses behavioral response in the rat formalin test: combination with intrathecal lidocaine produced profound suppression of the response

We investigated the effects of intrathecal (i.t.) lidocaine, inhalation sevoflurane, and a combination of i.t. lidocaine and sevoflurane on the formalin test in rats. Group 1 (control) received i.t. saline 10 microl. Groups 2 and 3 received i.t. lidocaine 200 microg and 400 microg, respectively. Groups 4-6 received 1.2%, 2.4% and 3.6% sevoflurane, respectively. Interaction of drugs was analyzed using a dose addition model. Group 7 received i.t. lidocaine 200 microg and 1.2% sevoflurane. The biphasic behavioral activity of the hindpaw of rats was observed. This study showed that i.t. lidocaine or inhalation sevoflurane before formalin injection, significantly suppressed the behavioral activity of the hindpaw of rats, and that this suppression was significantly potentiated by the co-administration of i.t. lidocaine and inhalation sevoflurane.

Naltrexone, but not atropine or yohimbine, antagonizes suppression of formalin-induced spinal sensitization by intrathecal nociceptin

We investigated the effects of spinal nociceptin on formalin-induced spinal sensitization and examined the role of the opioidergic, alpha 2-adrenergic and muscarinic cholinergic receptors in the nociceptin-produced suppression of spinal sensitization. The results demonstrated that spinal nociceptin suppressed the formalin-induced spinal sensitization in a dose-dependent manner (1, 5 and 10 nmol). The inhibitory effect of 10 nmol of nociceptin on spinal sensitization, was readily antagonized by naltrexone, but not by atropine or yohimbine. Each of the antagonists, naltrexone, atropine or yohimbine, alone had no effect on the formalin-induced spinal sensitization. Our results show that spinal nociceptin elicits dose-dependent, naltrexone-reversible suppression of spinal sensitization evoked by injection of formalin.

[Ultramicrostructural changes of articular cartilage, subchondral bone and synovium in human osteoarthritis of patellofemoral joint]

Ten patients with patellofemoral joint osteoarthritis (OA) were studied by electron microscope (SEM&TEM) to identify ultramicrostructural changes in the destroyed articular cartilage, subchondral bone and synovium. According to the results obtained, the author suggested that (1) Articular cartilage, subchondral bone and synovium in patellofemoral joint OA were noted to be in various degree of ultramicrostructural changes; (2) The cartilage degeneration in lateral compartment of patellofemoral joint were much more severe than that in medial compartment; (3) The subchondral bone had a strong tendency to undergo selerosis in the form of thicking and confluence of the trabeculae to form massive block of bone, which were not parallel to alteration of cartilage, and the rules of alteration were related to the character of loading; (4) The repair tissues of I-II grade degenerative cartilage were similar to normal cartilage, but those of III-IV grade degenerative cartilage were similar to fibrocartilage in many ways, because the source of repair tissues were different between them; (5) Alteration of synovium revealed only mild non-specific inflammatory changes following the changes of articular cartilage; (6) I-II grade patellofemoral joint OA was treated by conservative methods and III-IV grade OA should be treated by patellofemoral joint resurfacing.

Protoplast culture and plant regeneration ofPinellia ternata

A study was undertaken to develop a protoplast regeneration system for pinellia. A yield of 19 29 x 10(5) protoplasts/g F. W. could be obtained from cell suspension cultures incubated in a digestion enzyme solution with 2% cellulase Onzuka R-10, 10% pectinase (Sigma), 0.01% pectolyase Y23. K8P and modified MS media were used to culture protoplasts in: a) liquid, b) liquid-solid double layer, or c) agarose embedded protoplast culture. The former two were conducive to colony formation from protoplast-derived cells. The frequency of cell division was about 8% after 3 days in culture. Gradually adding fresh medium of lower osmotic pressure into the medium for protoplast culture favored cell division. Calli (1-2 mm in diameter) formed after 30-40 days in culture. The calli transferred onto medium supplemented with KT (0.5 mg 1(-1)) and NAA (0.2 mg 1)(-1)) could regenerate plants after 40-50 days. Of 47 plantlets transplanted into plots, 29 flowered and were fertile.