Effect of simulated microgravity on aged pea seed vigour and related physiological properties

We used simulated microgravity to treat aged pea seeds, in order to observe its effect on seed vigour and related physiological properties. The result shows that microgravity obviously promotes the germination rate, vitality index, germination index, and keeps the activity of protective enzyme, with conductivity and the content of MDA decreased. These effects gradually disappeared for a certain period after the microgravity administration.

Human growth hormone-regulated HOXA1 is a human mammary epithelial oncogene

Increased mammary epithelial expression of the human growth hormone (hGH) gene is associated with the acquisition of pathological proliferation. We report here that autocrine hGH production by human mammary carcinoma cells increased the expression and transcriptional activity of the homeobox domain containing protein HOXA1. Forced expression of HOXA1 in human mammary carcinoma cells resulted in increased total cell number primarily by the promotion of cell survival mediated by the transcriptional up-regulation of Bcl-2. HOXA1 also abrogated the apoptotic response of mammary carcinoma cells to doxorubicin. Forced expression of HOXA1 in mammary carcinoma cells, in a Bcl-2-dependent manner, resulted in dramatic enhancement of anchorage-independent proliferation and colony formation in soft agar. Finally, forced expression of HOXA1 was sufficient to result in the oncogenic transformation of immortalized human mammary epithelial cells with aggressive in vivo tumor formation. Herein, we have therefore provided a molecular mechanism by which autocrine hGH stimulation of human mammary epithelial cells may result in oncogenic transformation.

Synthesis, separation, and assignment of the seven geometric isomers of [Co(dien)(ibn)Cl]2+

All seven possible geometric isomers (four mer and three facial) for the [Co(dien)(ibn)Cl](2+) system have been synthesized (dien = diethylenetriamine, ibn = 1,2-diamino-2-methylpropane). Their structures in dimethyl sulfoxide solution have been uniquely determined by two-dimensional NMR spectroscopy (DQCOSY and NOESY).

Phosphorus sorption characteristics of a light-weight aggregate

A light-weight aggregate (LWA) made of expanded clay used as a filter media in wastewater treatment, was tested for sorption of phosphorus (P) in laboratory experiments. The objectives were to investigate the different P retention pools and how grain size, time, temperature and changed P concentration influenced the P binding mechanisms in this type of filter. Three different grain sizes (0-2 mm, 2-4 mm and 0-4 mm) were tested in a batch experiment. The isotherm for the P sorbed by the contact medium (including retention and fixation) was obtained under laboratory conditions. Fifty percent of the P sorption occurred in the first 4-8 hours. Temperature did not substantially influence P sorption for 0-2 mm grain size LWA. In the LWA suspension system, P desorption did not occur when the P content in the loading solution decreased. Fractionation analysis indicated that Ca-bound P, loosely-bound P, and Al-bound P were the predominant P retention pools. The loosely-bound P pool was determined primarily by the equilibrated P concentration in the system. Fe-bound P was negligible in the P sorption of LWA.

Polyaniline doped with modified gold nanoparticles and its electrochemical properties in neutral aqueous solutionElectronic supplementary information (ESI) available: TEM images and cyclic voltammograms. See http://www.rsc.org/suppdata/cc/b3/b309646g/

Doping polyaniline with COO(-)-modified gold nanoparticles by forming stable layer-by-layer multilayer films can shift its electroactivity to neutral pH. The films can electrocatalyze the oxidation of NADH and offer potential applications in other fields, e.g., optoelectronics or biosensing.

Identification of a JAK2-independent pathway regulating growth hormone (GH)-stimulated p44/42 mitogen-activated protein kinase activity. GH activation of Ral and phospholipase D is Src-dependent

We have demonstrated here that growth hormone (GH) stimulates the formation of the active GTP-bound form of both RalA and RalB in NIH-3T3 cells. Full activation of RalA and RalB by GH required the combined activity of c-Src and JAK2, both kinases activated by GH independent of the other. Activation of RalA and RalB by growth hormone did not require the activity of JAK2 per se. Ras was also activated by GH and was required for the GH-stimulated formation of GTP-bound RalA and RalB. Activation of RalA by GH subsequently resulted in increased phospholipase D activity and the formation of its metabolite, phosphatidic acid. GH-stimulated RalA-phospholipase D-dependent formation of phosphatidic acid was required for activation of p44/42 MAPK and subsequent Elk-1-mediated transcription stimulated by GH. Thus we report the identification of a JAK2-independent pathway regulating GH-stimulated p44/42 MAPK activity.

c-Cbl is a negative regulator of GH-stimulated STAT5-mediated transcription

We have previously demonstrated that cellular stimulation with GH results in the formation of a multiprotein signaling complex. One component of this multiprotein signaling complex is the adapter molecule c-Cbl. Here we have examined the role of c-Cbl in the mechanism of GH signal transduction. Forced expression of c-Cbl in NIH3T3 cells did not alter GH-stimulated Janus kinase 2 tyrosine phosphorylation nor GH-stimulated p44/42 MAPK activation and consequent Elk-1- mediated transcription. c-Cbl overexpression did, however, result in enhanced and prolonged GH-stimulated activation of phosphatidylinositol 3-kinase. Forced expression of c-Cbl did not affect GH-stimulated STAT5 tyrosine phosphorylation, nuclear translocation, nor binding to DNA but markedly abrogated GH-stimulated STAT5-mediated transactivation. c-Cbl overexpression resulted in increased ubiquitination and proteosomal degradation of STAT5 and increased degradation of GH-stimulated tyrosine phosphorylated STAT5. Cellular pretreatment with the proteosomal inhibitor MG132 reversed the effect of c-Cbl overexpression with prolonged duration of GH-stimulated STAT5 tyrosine phosphorylation and restoration of STAT5-mediated transcription. Thus, c-Cbl is a negative regulator of GH-stimulated STAT5-mediated transcription by direction of STAT5 for proteosomal degradation.

Regulation of the CFTR channel by phosphorylation

Cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels are regulated tightly by protein kinases and phosphatases. The regulatory domain of CFTR has about 20 potential sites for phosphorylation by protein kinases A (PKA) and C (PKC). The reason for this large number of sites is not known, however their conservation from fish to humans implies that they play important roles in vivo. PKA is an important activator, and its stimulation of CFTR is enhanced by PKC via mechanisms which are not fully understood. The physiological stimuli of CFTR are not known for some epithelia, and it appears likely that other serine/threonine and even tyrosine kinases also regulate CFTR in particular tissues. Phosphatases that deactivate CFTR have yet to be identified definitively at the molecular level, however CFTR is regulated by a membrane-bound form of protein phosphatase-2C (PP2C) in several cell types. Patch-clamp studies of channel rundown, co-immunoprecipitation, chemical cross-linking studies, and pull-down assays all indicate that CFTR and PP2C are closely associated within a stable regulatory complex. Understanding the regulation of CFTR by PP2C is a priority due to its potential as a target for pharmacotherapies in the treatment of cystic fibrosis.

Thioglycosides protected as trans-2,3-cyclic carbonates in chemoselective glycosylations

Thioglycosides protected as trans-2,3-cyclic carbonates have significantly lower anomeric reactivities than fully acylated and N-acyl-protected thioglycosides and can be used as acceptors in chemoselective glycosylations with a wide range of thioglycosyl donors. The resulting thioglycosides can be further activated to give 1,2-cis-linked glycosides. [reaction: see text]

[Neuronavigation-assisted resection of gliomas near eloquent regions]

OBJECTIVE

To evaluate the effect of the neuronavigation system in operation of gliomas near eloquent regions.

METHOD

The brain LAB VV2 navigation system was used in 11 patients with gliomas near eloquent regions. The value of this system for glioma resection was assessed, and the accuracy and notice for application were discussed.

RESULTS

The mean registration error was (1.5 +/- 0.7) mm in the patients. Total lesion removal was achieved in 9 patients (81.8%). The clinical status of all patients improved, and their functions of motor were not significantly affected. No complications were attributed to the use of this system.

CONCLUSION

The neuronavigation system is reliable and accurate in surgical treatment of gliomas near eloquent regions. It increases the fraction of radical in glioma resection without injury to the critical functions.

The effect of electro-acupuncture on motor function recovery in patients with acute cerebral infarction: a randomly controlled trial

The aim of this study is to investigate the effect of electro-acupuncture treatment in acute phase of cerebral infarction on the motor functions. In this randomly controlled trial, 86 patients were allocated to two groups, the experimental group given clinical and electro-acupuncture treatments for a period of 4 weeks, and the control group given clinical treatment plus active and/or passive functional exercise. The result showed that the level of impairment and disability in both groups were improvement according to the Chinese Stroke Scale, Brunnstrom-Fugl-Meyer score, and Barthel Index throughout the study and 3 months after. The motor functions and the activities of daily living (ADL) were improved significantly in the electro-acupuncture group as compared with the control group (P < 0.05). Also, the results showed greater reduction of neurological deficit in the electro-acupuncture group than in the control group.

CONCLUSION

Early acupuncture treatment for acute stroke patients may improve motor functions, and consequently the activities of daily living.

Retrovirus-mediated expression of apolipoprotein A-I in the macrophage protects against atherosclerosis in vivo

We have previously reported that the lack of apolipoprotein (apo) E expression by macrophages promotes foam cell formation in vivo. Because transgenic mice overexpressing human apoA-I from the liver (h-apoA-I TgN) are protected from the atherogenesis induced by apoE deficiency, we hypothesized that the presence of apoA-I in the vessel wall could reduce the negative effect of apoE deficiency on lesion growth. To address this issue, we used both retroviral transduction and transgenic approaches to produce in vivo systems where apoA-I is expressed from macrophages. In the retroviral transduction study, apoA-I-deficient (apoA-I(-/-)) mice reconstituted with apoE-deficient (apoE(-/-)) bone marrow cells that were infected with a retroviral vector expressing human apoA-I (MFG-HAI) had 95% lower atherosclerotic lesion area than that of recipients of apoE(-/-) bone marrow cells infected with the parental virus (MFG). To determine whether the protective effect of locally produced apoA-I was due to the lack of systemic apoA-I, we conducted a different experiment using h-apoA-I TgN mice as recipients of apoE(-/-) bone marrow with or without human apoA-I (driven by a macrophage-specific transgene defined as mphi-AI). Aortic lesion area in apoE(-/-)/mphi-AI --> h-apoA-I TgN mice was decreased by 85% compared with apoE(-/-) --> h-apoA-I TgN mice. These data demonstrate that expression of apoA-I from macrophages protects against atherogenesis without affecting plasma apoA-I and high density lipoprotein cholesterol levels.

Apolipoprotein E polymorphism in the early onset of coronary heart disease

OBJECTIVE

To assess the relationship between apolipoprotein E (apoE) polymorphism and the early onset of coronary heart disease (CHD) and the effect of apoE on lipids and lipoproteins in healthy Chinese subjects.

METHODS

Sixty-eight patients with CHD younger than 55 years (CHD1), 136 patients with CHD older than 65 years (CHD2), and 136 healthy subjects were enrolled, and their plasma levels of triglyceride (TG), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C) were determined. The apoE genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

apoE 3/4 genotype and E4 allele frequency in the CHD1 group were higher than those in the CHD2 group and healthy subjects, while no differences were found between CHD2 and healthy subjects. Meanwhile, the plasma levels of TC and low density lipoprotein cholesterol (LDL-C) were higher in the CHD2 group than in both CHD1 group and healthy subjects. Each apoE isoprotein has variable TC and LDL-C levels that is E2 (E2/2 + E2/3) < E3(E3/3) < E4(E4/4 + E3/4).

CONCLUSION

apoE is one of the genetic factors that affect TC and LDL-C levels, and apoE 4 has a very close relation to CHD, suggesting that apoE 4 is an independent genetic factor of the early onset of CHD.

Signal transduction via the growth hormone receptor

Rapid progress has been made recently in the definition of growth hormone (GH) receptor signal transduction pathways. It is now apparent that many cytokines, including GH, share identical or similar signalling components to exert their cellular effects. This review provides a brief discourse on the signal transduction pathways, which have been demonstrated to be utilized by GH. The identification of such pathways provides a basis for understanding the pleiotropic actions of GH. The mechanisms by which the specific cellular effects of GH are achieved remain to be elucidated.

Serum- and glucocorticoid-inducible kinase SGK phosphorylates and negatively regulates B-Raf

Phosphorylation can both positively and negatively regulate activity of the Raf kinases. Akt has been shown to phosphorylate and inhibit C-Raf activity. We have recently reported that Akt negatively regulates B-Raf kinase activation by phosphorylating multiple residues within its amino-terminal regulatory domain. Here we investigated the regulation of B-Raf by serum and glucocorticoid-inducible kinase, SGK, which shares close sequence identity with the catalytic domain of Akt but lacks the pleckstrin homology domain. We observed that SGK inhibits B-Raf activity. A comparison of substrate specificity between SGK and Akt indicates that SGK is a potent negative regulator of B-Raf. In contrast to Akt, SGK negatively regulates B-Raf kinase activity by phosphorylating only a single Akt consensus site, Ser(364). Under similar experimental conditions, SGK displays a measurably stronger inhibitory effect on B-Raf kinase activity than Akt, whereas Akt exhibits a more inhibitory effect on the forkhead transcription factor, FKHR. The selective substrate specificity is correlated with an enhanced association between Akt or SGK and their preferred substrates, FKHR and B-Raf, respectively. These results indicate that B-Raf kinase activity is negatively regulated by Akt and SGK, suggesting that the cross-talk between the B-Raf and other signaling pathways can be mediated by both Akt and SGK.

[Studies on transference of hydrogenase genes of Rhizobium arachis]

The hydrogen-uptake genes were transferred into wild Rhizobium arachis Ra strains (Hup-, Nif+, Apr) by triparental mating using pRK2013 as help plasmid. A transconjugant R. arachis Rz34-2(Hup+, Nif+, Apr, Tcr) which expressed high activities of hydrogenase and nitrogenase under free-living and symbiotic state was screened. Peanut inoculation test with recipient R. arachis Ra34, transcojugant Rz34-2 and control strain R. arachis L8-3 (Hup+, Nif+) was carried out respectively. The results showed that, compare to treatment without inoculation, inoculation with R. arachis Ra34 and R. arachis L8-3, the dry weight of leaf inoculated with transconjuant Rz34-2 increased 6.2%, 7.6% and 6.3% respectively; the N-content of seed increased 8.8%, 10.0% and 6.0%; the output increased 18.8%, 10.5% and 10.7%. This suggested that legume plants inoculated with Rhizobium strains (Hup+) were more efficient to accumulate N and to increase its output.

Anterior approach to the second thoracic vertebral body for surgical treatment (vertebrectomy, bone grafting, and titanium alloy plate fixation)

The surgical approach to the second thoracic vertebral body is difficult from the anterior side. A 38-year-old woman suffering from plasmacytoma in the second thoracic vertebra showed paraplegia for 2 weeks prior to surgery. X-ray, computed tomography (CT), and magnetic resonance imaging (MRI) examinations indicated breakdown of the second thoracic vertebral body and arch, associated with spinal cord compression. A 99mTc bone scintigram showed accumulation only in the second thoracic vertebra. After one course of chemotherapy with cyclophosphamide and prednisone (CP protocol), surgery was carried out. The incision was made on the right side of the anterior of the neck, from the middle half of the sternocleidomastoideus along the anterior edge to the jugular notch of the sternum. After cutting the platysma, severing the sternohyoideus, splitting the sternothyroid muscle, and forming a compartment between the esophagus and vagina carotica, we extended the incision to the sternum. Without wedging the sternum, we separated tissue from the posterior of the sternum to the second and third thoracic vertebrae, excised the second thoracic vertebra to expose the hard spinal meninges, and removed the tumor in the vertebral canal to release the compression on the spinal cord. An autogeneous bone graft, taken from the right ilium (1.5 x 1.5 x 3 cm in size), was implanted between the first and third thoracic vertebrae, and a spinal titanium alloy plate was used to increase fixation between the first and third thoracic vertebrae from the front. During the surgery, 800 ml of blood was transfused. On the fifth postsurgical day, the patient could walk normally with a neck collar, and the paraplegia was completely alleviated, with no complications.

Multiple transcription-factor genes are early targets of phytochrome A signaling

The phytochrome family of sensory photoreceptors directs adaptational changes in gene expression in response to environmental light signals. Using oligonucleotide microarrays to measure expression profiles in wild-type and phytochrome A (phyA) null-mutant Arabidopsis seedlings, we have shown that 10% of the genes represented on the array are regulated by phyA in response to a continuous far-red light signal. Strikingly, 44% of the genes responding to the signal within 1 h are predicted to encode multiple classes of transcriptional regulators. Together with previous data, this observation suggests that phyA may regulate seedling photomorphogenesis by direct targeting of light signals to the promoters of genes encoding a master set of diverse transcriptional regulators, responsible in turn for orchestrating the expression of multiple downstream target genes in various branches of a phyA-regulated transcriptional network.

Cell growth and by-product formation in a pyruvate kinase mutant of E. coli

In this paper, we report on the analysis of acid formation in an E. coli pyk mutant. The results demonstrate that acid formation is insignificant for both the wild-type and the mutant at low glucose concentrations. However, at relatively high glucose concentrations, acid formation remains very low for the mutant but is significant for the wild-type. This substantial reduction in acids is accompanied by an increase in CO(2) production. Moreover, unlike the B. subtilis pyk mutant, the E. coli pyk mutant did not show a substantial increase in the PEP pool.

[Expression of telomerase reverse transcriptase and its relationship with tumor suppressor gene p53 in HCC]

OBJECTIVE

To explore the expression of human telomerase reverse transcriptase (HTERT) and its relationship with tumor suppressor gene p53.

METHODS

RNA-RNA in situ hybridization (ISH) technique was applied to localize the expression of HTERT mRNA and immunohistochemistry (IHC) was used to observe the p53 protein expression in 34 specimens of HCC and their corresponding non-cancerous tissues. Both the significance of HTERT mRNA expression in the different histopathologic characters and its relationship with p53 protein were investigated.

RESULTS

HTERT was detected in tumor tissue in 30 of 34 cases (88.2%), and all the 6 cases of small cancer (diameter<3cm) were positive. The positive rate of HTERT mRNA was higher in the tumor tissues with low-differentiation, extra- or intra-hepatic metastasis, uncompleted fibrotic capsule and/or the non-cancerous tissue with chronic active lesions or positive HBsAg. Intensive signal was seen both in the HCC cells along the front of invasive area and in a few non-cancerous liver cells with dysplasia. Of all 34 HCC, p53 protein was presented in 25 cases. There was a correlation between the expression of HTERT mRNA and of p53 protein. The coincidence rate of the expression (HTERT+/p53+ and HTERT-/p53-) was 79.4%. More intensity of HTERT signal could be seen in the cases of positive p53. HTERT mRNA was not found in normal liver tissues.

CONCLUSIONS

High expression of HTERT mRNA is proved in most cases of HCCs. HTERT expression may relate to the pathogenesis and the invasion of HCC. p53 may play a role in regulating the expression of HTERT.

Autocrine human growth hormone (hGH) regulation of human mammary carcinoma cell gene expression. Identification of CHOP as a mediator of hGH-stimulated human mammary carcinoma cell survival

By use of cDNA array technology we have screened 588 genes to determine the effect of autocrine production of human growth hormone (hGH) on gene expression in human mammary carcinoma cells. We have used a previously described cellular model to study autocrine hGH function in which the hGH gene or a translation-deficient hGH gene was stably transfected into MCF-7 cells. Fifty two of the screened genes were regulated, either positively () or negatively (), by autocrine production of hGH. We have now characterized the role of one of the up-regulated genes, chop (gadd153), in the effect of autocrine production of hGH on mammary carcinoma cell number. The effect of autocrine production of hGH on the level of CHOP mRNA was exerted at the transcriptional level as autocrine hGH increased chloramphenicol acetyltransferase production from a reporter plasmid containing a 1-kilobase pair fragment of the chop promoter. The autocrine hGH-stimulated increase in CHOP mRNA also resulted in an increase in CHOP protein. As a consequence, autocrine hGH stimulation of CHOP-mediated transcriptional activation was increased. Stable transfection of human CHOP cDNA into mammary carcinoma cells demonstrated that CHOP functioned not as a mediator of hGH-stimulated mitogenesis but rather enhanced the protection from apoptosis afforded by hGH in a p38 MAPK-dependent manner. Thus transcriptional up-regulation of chop is one mechanism by which hGH regulates mammary carcinoma cell number.

A highly efficient synthetic strategy for polymeric support synthesis of Le(x), Le(y), and H-type 2 oligosaccharides

The O-protecting groups Levulinoyl (Lev) and 9-fluroenylmethoxycarbonyl (Fmoc) offer an attractive set of orthogonal protecting groups which are compatible with base sensitive N-trichloroethoxylcarbonyl (Troc) group. B exploiting these orthogonal protecting groups and a novel phenolic ester linker, a series of oligosaccharide of biological importance, Le(x), H-type 2, and Le(y), were synthesized on the polytheylene glycol resin MPEG (Mw 5000). The products bearing a p-hydroxybenzyl group could be easily converted into glycosyl donors for further synthesis. Using this strategy, a spacer containing tumor antigen Le(y)-Lac hexasaccharide was described. The artificial spacer at the reducing end provides an opportunity for selective conjugation to an appropriate carrier protein for immunlogical studies.

Comparison of in vivo dopamine D2 receptor binding of [(123)I]AIBZM and [(123)I]IBZM in rat brain

[(123)I]AIBZM, (S)-5-[(123)I]-Iodo-N-[(1-ethyl-2-pyrrolidinyl)]methyl-4-amine-2-methoxybenzamide is a derivative with high affinity for the D2 receptor. Labeling was achieved by the Iodogen method. The in vivo affinity for the D2 receptor and the biological characteristics were performed in rats. The brain uptake of [(123)I]AIBZM was significantly lower, however the striatum/cerebellum ratio (2h p.i.) was higher than that of [(123)I]IBZM. Because of the high affinity and its possibly lower unspecific binding compared to [(123)I]IBZM, [(123)I]AIBZM may be a potential imaging agent for the D2 dopamine receptor.

[Effect of sensitized lymphocytes on rabbit calvarial osteoblasts]

OBJECTIVE

To study the effects of sensitized T lymphocytes on osteoblastic proliferation and differentiation.

METHODS

Sensitized lymphocytes were obtained from a rabbit sensitized by chromium, and lymphocyte cultured mediums (LCM) were collected. Osteoblasts were obtained from new-born rabbit calvaria. The osteoblasts were identified with alkaline phosphatase staining and mineralization in vitro. By osteoblast cultured in vitro, osteoblastic proliferation, and production of alkaline phosphatase and osteocalcin were evaluated in three conditions: without LCM, with LCM not stimulated by Cr(6+) and with LCM stimulated by Cr(6+).

RESULTS

The cells from rabbit calvaria were positive to ALP staining and could form calcium node in vitro. The sensitized LCM could inhibit proliferation of osteoblasts, increase alkaline phosphatase production and decrease osteocalcin production. These results all had statistically significant difference by ANOVA.

CONCLUSION

Sensitized T lymphocytes could decrease the number of mature osteoblasts and impede the formation of mature mineralized bone.

A MILP-based flux alternative generation and NMR experimental design strategy for metabolic engineering

A mixed-integer linear program (MILP) is described that can enumerate all the ways fluxes can distribute in a metabolic network while still satisfying the same constraints and objective function. The multiple solutions can be used to (1) generate alternative flux scenarios that can account for limited experimental observations, (2) forecast the potential responses to mutation (e.g., new reaction pathways may be used), and (3) (as illustrated) design (13)C NMR experiments such that different potential flux patterns in a mutant can be distinguished. The experimental design is enabled by using the MILP results as an input to an isotopomer mapping matrices (IMM)-based program, which accounts for the network circulation of (13)C from a precursor such as glucose. The IMM-based program can interface to common plotting programs with the result that the user is provided with predicted NMR spectra that are complete with splittings and Lorentzian line-shape features. The example considered is the trafficking of carbon in an Escherichia coli mutant, which has pyruvate kinase activity deleted for the purpose of eliminating acetate production. Similar yields and extracellular measurements would be manifested by the flux alternatives. The MILP-IMM results suggest how NMR experiments can be designed such that the spectra of glutamate for two flux distribution scenarios differ significantly.

Boiler briquette coal versus raw coal: Part I--Stack gas emissions

Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM2.5, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2.5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM2.5, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.

Photodynamic therapy in the canine prostate using motexafin lutetium

Our purpose was to determine the feasibility of comprehensive treatment of the canine prostate with photodynamic therapy (PDT) using motexafin lutetium (Lu-Tex) and to evaluate the toxicity and tissue effects associated with this treatment. Twenty-five adult male beagles with normal prostate glands were given an i.v. injection of the second-generation photosensitizer Lu-Tex (2-6 mg/kg). An additional two dogs were used as controls and did not receive any photosensitizing drug. All 27 dogs underwent laparotomy to expose the prostate. Three hours postinjection, a total dose of 75-150 J/cm of 732 nm laser light was delivered interstitially and/or transurethrally to the prostate via cylindrical diffusing fibers. Dogs were euthanized between 2 days and 3 months after PDT. All subjects were monitored for clinical evidence of toxicity. Specimens were examined macroscopically and microscopically to characterize the tissue reaction and assess extent of tissue effect as a result of treatment. Interstitial and/or transurethral PDT were successfully delivered in all dogs with no perioperative complications. No clinical evidence of acute urinary obstruction or rectal bleeding was noted. At all dose levels, macroscopic and microscopic evaluation revealed a prostatic tissue reaction characterized initially (within 48 h) by inflammation and necrosis followed by fibrosis and glandular epithelial atrophy. Comprehensive treatment of the entire prostate could be achieved using the interstitial alone approach or combined transurethral and interstitial approach. The transurethral alone approach did not result in complete coverage of the prostate. Dogs receiving transurethral or combined interstitial and transurethral treatment developed erythema and urethral epithelial disruption at all dose levels. Those receiving combined treatment at the highest dose level (Lu-Tex 6 mg/kg, 150 J/cm light) developed urethral fistulae and peritonitis. Dogs treated with the interstitial alone approach were found to have the least amount of urethral damage. Comprehensive treatment of the canine prostate with Lu-Tex PDT is feasible using an interstitial alone or combined interstitial and transurethral approach. The interstitial alone technique results in the least amount of toxicity. The prostatic tissue reaction to treatment is characterized by initial inflammation and necrosis followed by fibrosis and glandular epithelial atrophy.

[Geostrophic deviation analysis of regional effects of protective forest system in reducing windspeed in north Liaoning plain]

East Asian synoptic charts and ground wind data in April and May of four counties of north Liaoning plain were selected to calculate the regional effects of protective forest system in reducing windspeed by geostrophic deviation method. The results show that the protection effects increased with increasing forestration area. Different protection effects of protective forest appeared at different daytime, with the greatest at 14:00 and smallest at 2:00, and the average windspeed reduced 13.3%. The characteristics of the geostrophic deviation method was also discussed.

Preclinical evaluation of motexafin lutetium-mediated intraperitoneal photodynamic therapy in a canine model

Intraperitoneal photodynamic therapy (IP PDT) is an experimental cancer treatment in clinical development for the treatment of peritoneal carcinomatosis and sarcomatosis. A canine study of motexafin lutetium (Lu-Tex)-mediated IP PDT was performed to evaluate normal tissue toxicities of this treatment in the presence and absence of a bowel resection and to assess the feasibility of measuring Lu-Tex fluorescence in abdominal tissues. Thirteen dogs were treated with Lu-Tex (0.2-2 mg/kg) i.v. 3 h before laparotomy and 730-nm light delivery (fluences, 0.5-2.0 J/cm2; average fluence rate <150 mW/cm2). Laparoscopy was performed 7-10 days after the procedure to assess acute toxicities. In situ fluorescence spectra were obtained from various abdominal tissues before and after light delivery using a fiber array probe with fixed-source detector distances. Lu-Tex-mediated IP PDT was well tolerated at the doses of drug and light studied. Bowel toxicity was not observed in animals treated with a bowel resection before PDT. Mild transient liver function test abnormalities without associated clinical sequelae were observed. No gross PDT-related abnormalities were observed at laparoscopy or necropsy; however, thickening in the glomerular capillary wall and the mesangium were noted microscopically in the kidneys of seven dogs. No renal function abnormalities were found. Analysis of the fluorescence spectra from intra-abdominal tissues suggests that measurements of Lu-Tex in situ are feasible and may provide a way of assessing photosensitizer concentration in vivo without the need for a biopsy. These results support the continued development of Lu-Tex as a candidate photosensitizer for IP PDT.

The effects of autocrine human growth hormone (hGH) on human mammary carcinoma cell behavior are mediated via the hGH receptor

The human GH (hGH) antagonist B2036 combines a single amino acid substitution impairing receptor binding site 2 (G120K) with eight additional amino acid substitutions that improve binding site 1 affinity. B2036 does not bind, activate, or antagonize the human PRL receptor and therefore is suitable to determine cellular effects mediated specifically through the hGH receptor. We have used this hGH receptor specific antagonist in MCF-7 cells stably transfected with either the hGH gene (MCF-hGH) or a translation deficient hGH gene (MCF-MUT) to determine whether the effects of autocrine hGH on mammary carcinoma cell behavior are mediated via the hGH receptor. Enhanced JAK2 tyrosine phosphorylation observed in MCF-hGH cells compared with MCF-MUT cells is abrogated by B2036 as is the autocrine hGH stimulated increase in total cell number and DNA synthesis. Interestingly, autocrine hGH functions as a potent inhibitor of apoptosis induced by serum withdrawal compared with exogenously added hGH, and the protection against apoptosis afforded by autocrine hGH is abrogated by B2036. B2036 also inhibited autocrine hGH stimulated transcriptional activation mediated by either STAT5, CHOP (p38 MAP kinase specific) or Elk-1 (p44/42 MAP kinase specific). Finally, B2036 inhibited the autocrine hGH-dependent enhancement of the rate of mammary carcinoma cell spreading on a collagen matrix. Thus, the effects of autocrine hGH on human mammary carcinoma cell behavior are mediated via the hGH receptor.

Phase II trial of debulking surgery and photodynamic therapy for disseminated intraperitoneal tumors

BACKGROUND

Photodynamic therapy (PDT) combines photosensitizer drug, oxygen, and laser light to kill tumor cells on surfaces. This is the initial report of our phase II trial, designed to evaluate the effectiveness of surgical debulking and PDT in carcinomatosis and sarcomatosis.

METHODS

Fifty-six patients were enrolled between April 1997 and January 2000. Patients were given Photofrin (2.5 mg/kg) intravenously 2 days before tumor-debulking surgery. Laser light was delivered to all peritoneal surfaces. Patients were followed with CT scans and laparoscopy to evaluate responses to treatment.

RESULTS

Forty-two patients were adequately debulked at surgery; these comprise the treatment group. There were 14 GI malignancies, 12 ovarian cancers and 15 sarcomas. Actuarial median survival was 21 months. Median time to recurrence was 3 months (range, 1-21 months). The most common serious toxicities were anemia (38%), liver function test (LFT) abnormalities (26%), and gastrointestinal toxicities (19%), and one patient died.

CONCLUSIONS

Photofrin PDT for carcinomatosis has been successfully administered to 42 patients, with acceptable toxicity. The median survival of 21 months exceeds our expectations; however, the relative contribution of surgical resection versus PDT is unknown. Deficiencies in photosensitizer delivery, tissue oxygenation, or laser light distribution leading to recurrences may be addressed through the future use of new photosensitizers.

Orchestrated transcription of key pathways in Arabidopsis by the circadian clock

Like most organisms, plants have endogenous biological clocks that coordinate internal events with the external environment. We used high-density oligonucleotide microarrays to examine gene expression in Arabidopsis and found that 6% of the more than 8000 genes on the array exhibited circadian changes in steady-state messenger RNA levels. Clusters of circadian-regulated genes were found in pathways involved in plant responses to light and other key metabolic pathways. Computational analysis of cycling genes allowed the identification of a highly conserved promoter motif that we found to be required for circadian control of gene expression. Our study presents a comprehensive view of the temporal compartmentalization of physiological pathways by the circadian clock in a eukaryote.

Immunization with recombinant canarypox vectors expressing membrane-anchored glycoprotein 120 followed by glycoprotein 160 boosting fails to generate antibodies that neutralize R5 primary isolates of human immunodeficiency virus type 1

Antibodies generated by candidate HIV-1 vaccines in a phase I clinical trial were assessed for neutralizing activity with a panel of eight well-characterized, genetically diverse clade B primary isolates having an R5 phenotype. The vaccines consisted of one of three different recombinant canarypox vectors expressing membrane-anchored HIV-1(MN)gp120 (ALVAC vCP205, vCP1433, and vCP1452) followed by boosting with a soluble gp160 hybrid consisting of MNgp120 and the majority of gp41 from strain IIIB. Serum samples from a subset of volunteers in each arm of the trial, containing moderate to high titers of neutralizing antibodies to HIV-1 MN, were analyzed. Competition assays with peptides revealed that the majority of neutralizing activity was specific for the MN-V3 loop. Despite MN-specific neutralization titers that sometimes exceeded 1:500, no neutralization of primary isolates was detected and, in some cases, mild infection enhancement was observed. In addition, little or no neutralization of the HIV-1 IIIB heterologous T cell line-adapted strain of virus was detected. These results reinforce the notion that monovalent HIV-1 ENV is a poor immunogen for generating cross-reactive neutralizing antibodies.

Intermolecular aglycon transfer of ethyl thioglycosides can be prevented by judicious choice of protecting groups

Unexpected intermolecular aglycon transfer occurred in chemoseletive glycosylations using glycosyl fluorides or trichloroacetimidates as glycosyl donors and partially protected thioglycosides as glycosyl acceptors. It is shown that this problem can be addressed by fine-tuning of the reactivity of the anomeric thioalkyl moiety and hydroxyl of the acceptor.

Induction of Ro/SSA antigen expression on keratinocyte cell membrane by heat shock and phorbol 12-myristate 13-acetate as well as estradiol and ultraviolet B

Skin is one of the main target organs in lupus erythematosus and in some circumstances, skin lesions precede systemic manifestations. Previous studies have demonstrated that Ro/SSA antigen antibody might be involved in the pathogenesis of lupus erythematosus. The present study was performed to investigate the factors regulating expression of Ro/SSA antigens on the cell surface of keratinocytes. Cultured normal human keratinocytes were treated with 50-200 mJ/cm(2) of ultraviolet B (UVB) irradiation, 10(-9) to 10(-5) mol/l of 17beta-estradiol, 5-10 microg/l of phorbol 12-myristate 13-acetate (PMA), and 42 and 45 degrees C heat shock, respectively. The Ro/SSA antigen expressions were determined by indirect immunofluorescence. The results showed that keratinocytes receiving UVB irradiation expressed Ro/SSA antigen on cell membranes in a dose-dependent fashion. 17beta-estradiol treatment also induced Ro/SSA antigen expression dose-dependently. Keratinocyte expression of Ro/SSA antigens was also induced by heat shock stimulation. The 45 degrees C heat shock showed a stronger effect than 42 degrees C heat shock. Keratinocytes incubated for 24 h after heat shock had more antigen-expressing cells than those incubated for 6 h after heat shock. PMA at 5 and 10 microg/l also strongly induced Ro/SSA antigen expression. These results suggest that Ro/SSA antigen expression can be regulated by many factors and that protein kinase C signal transduction pathway might be involved in this process.

[Role of peroxynitrite on airway hyperresponsiveness in asthmatic guinea-pigs]

OBJECTIVE

To study the formation and localization of peroxynitrite(ONOO-) in the lung tissues of asthmatic guinea pig and investigate the effects of ONOO- on airway hyperresponsiveness in asthma.

METHODS

18 guinea pigs were randomly divided into three groups of 6 each: (1) asthmatic group: guinea pigs were injected intraperitoneally with 1 ml of 10% ovalbumin. After 14 days, the animals were exposed to aerosol of 1% OVA; (2) aminoguonidine (AG) group: Animal immunization was the same as above, but 1 h before the animals were exposed to OVA aerosol, 10 mg/kg AG were injected intraperitoneally. (3) control group. The formation and localization of ONOO- in the lung tissues of the guinea-pig asthma model were observed by immunohistochemical detection. The effect of exogenous ONOO- on contractions of isolated tracheal strips of the guinea-pigs to various concentrations of histamine was examined. The damage of airway epithelial cells induced by ONOO- was observed by electron microscopy.

RESULTS

There was strong immunoreactivity for nitrotyrosine (NT), a specific marker of ONOO- formation in vivo, in the airway epithelial cells and inflammatory cells surrounding small airways of the guinea-pigs with asthma. The AG group showed significantly decreased number of NT positive cells in the lung tissues. There were only a few NT positive cells in the control group. The responsiveness of isolated tracheal strips to various concentration of histamine(except 10(-8) mol/L) in the ONOO- 0.5 mmol/L group were significantly increased compared with the vehicle group. (P < 0.05, P < 0.01 or P < 0.001). The sensitivity of isolated tracheal strips to histamine in the ONOO- 0.5 mmol/L group were also increased compared with the vehicle group(P < 0.001). Electron microscopical observation of the airways revealed airway epithelial injury and shedding.

CONCLUSION

There was ONOO- overproduction in airway epithelial cells of asthmatic guinea-pigs, which may contribute to airway epithelial damage and hyperresponsiveness in asthma.

Characterization of growth and acid formation in a Bacillus subtilis pyruvate kinase mutant

Based on measurements and theoretical analyses, we identified deletion of pyruvate kinase (PYK) activity as a possible route for elimination of acid formation in Bacillus subtilis cultures grown on glucose minimal media. Evidence consistent with the attenuation of PYK flux has come from metabolic flux calculations, metabolic pool and enzymatic activity measurements, and a series of nuclear magnetic resonance experiments, all suggesting a nearly complete inhibition of PYK activity for glucose-citrate fed cultures in which the amount of acid formation was nearly zero. In this paper, we report the construction and characterization of a pyk mutant of B. subtilis. Our results demonstrate an almost complete elimination of acid production in cultures of the pyk mutant in glucose minimal medium. The substantial reduction in acid production is accompanied by increased CO(2) production and a reduced rate of growth. Metabolic analysis indicated a dramatic increase in intracellular pools of phosphoenolpyruvate (PEP) and glucose-6-P in the pyk mutant. The high concentrations of PEP and glucose-6-P could explain the decreased growth rate of the mutant. The substantial accumulation of PEP does not occur in Escherichia coli pyk mutants. The very high concentration of PEP which accumulates in the B. subtilis pyk mutant could be exploited for production of various aromatics.

HIV-1 genotypes in peripheral blood monocytes

CD4+ T cells and tissue macrophages are well defined as the major targets for human immunodeficiency virus type 1 (HIV-1) infection and replication, and their infection accounts for many aspects of HIV-1 pathogenesis in vivo. HIV-1 genotype and phenotype in monocytes and their potential roles in pathogenicity in vivo remain unknown. Herein is an overview of our initial work on HIV-1 genotype in purified CD14+ monocytes isolated longitudinally during the course of infection starting from the time of infection. Our data provide evidence for HIV-1 evolution in monocytes and their role as a reservoir of HIV-1 in vivo. A better understanding of HIV-1 in monocytes may greatly help the development of new therapeutic strategies for HIV-1 infection.