Characterization of immune responses following intranasal immunization with the Mycobacterium bovis CFP-10 protein expressed by attenuated Salmonella typhimurium

Culture filtrate protein 10 (CFP-10) from Mycobacterium bovis or Mycobacterium tuberculosis (MTB) is an immunodominant T-cell antigen expressed during the early stages of infection. Because lungs are most commonly associated with primary M. bovis infections, specific immunity at this site is desirable for protection. Therefore, in this study, immune responses generated in mouse lung, spleen and Peyer's patches were examined following intranasal (i.n.) immunization with Salmonella typhimurium- expressing CFP-10. Cells harvested from the lungs and Peyer's patches of immunized mice and then stimulated with CFP-10 produced significant levels of IFN-γ and these mice developed elevated serum IgG and lung IgA anti-CFP-10 responses, suggesting that this approach induced potent anti-CFP-10 mucosal immunity. Our study demonstrates that i.n. administration of CFP-10 expressed by S. typhimurium represents an effective way to induce efficient immune response to M. bovis antigen.

Epidermal growth factor receptor transactivation by the cannabinoid receptor (CB1) and transient receptor potential vanilloid 1 (TRPV1) induces differential responses in corneal epithelial cells

Corneal epithelial injury induces release of endogenous metabolites that are cannabinoid receptor 1 (CB1) and transient receptor potential vanilloid 1 (TRPV1) agonists. We determined the functional contributions by CB1 and TRPV1 activation to eliciting responses underlying wound healing in human corneal epithelial cells (HCEC). Both the selective CB1 and TRPV1 agonists (i.e., WIN55,212-2 [WIN] and capsaicin [CAP], respectively) induced EGFR phosphorylation whereas either inhibition of its tyrosine kinase activity with AG1478 or functional blockage eliminated this response. Furthermore, EGFR transactivation was abolished by inhibitors of proteolytic release of heparin bound EGF (HB-EGF). CB1-induced Ca(2+) transients were reduced during exposure to either the CB1 antagonist, AM251 or AG1478. Both CAP and WIN induced transient increases in Erk1/2, p38, JNK1/2 MAPK and Akt/PI-3K phosphorylation status resulting in cell proliferation and migration increases which mirrored those elicited by EGF. Neither EGF nor WIN induced any increases in IL-6 and IL-8 release. On the other hand, CAP-induced 3- and 6-fold increases, which were fully attenuated during exposure to CPZ, but AG1478 only suppressed them by 21%. The mixed CB1 and TRPV1 antagonist, AM251, enhanced the CAP-induced rise in IL-8 release to a higher level than that elicited by CAP alone. In conclusion, CB1 and TRPV1 activation induces increases in HCEC proliferation and migration through EGFR transactivation leading to global MAPK and Akt/PI-3K pathway stimulation. On the other hand, the TRPV1-mediated increases in IL-6 and IL-8 release are elicited through both EGFR dependent and EGFR-independent signaling pathways.

The roles of microRNAs in heart diseases: a novel important regulator

MicroRNAs (miRNAs) are non-coding single-stranded RNAs with about 21~23 nucleotides in length, which originate from encoding genes in nucleus. miRNAs play an inhibitory role in gene expression in a post-transcriptional level by partially complementary binding to the 3' unstranlated region (UTR) of target mRNAs. Large bodies of evidence have shown that miRNAs were involved in various diseases, such as cancer, infectious diseases, diabetes etc, and rising as critical modulators of pathological processes. Lately, some highlight articles revealed that the altered expression of miRNAs such as miR-1, miR-133, miR-21, miR-208 etc in hearts also contributed to cardiovascular diseases, such as heart ischemia, cardiac hypertrophy, and arrhythmias. Moreover, miRNAs were also identified to regulate heart development. These exciting findings not only improve our understanding of the molecular mechanisms of heart diseases, but also provide a new class of potential molecular targets. miRNAs, for the development of novel agents to treat heart diseases. Here, we summarized the recent discoveries about the role of miRNAs in cardiac physiological and pathological functions, and then discussed about their therapeutic potentials for heart diseases.

Increased short circuit current in organic photovoltaic using high-surface area electrode based on ZnO nanowires decorated with CdTe quantum dots

A photosensitized high-surface area transparent electrode has been employed to increase the short circuit current of a photovoltaic device with a blend of poly(3-hexylthiophene) (P3HT) and (6,6)-phenyl C61 butyric acid methyl ester (PCBM) as the active layer. This is achieved by directly growing ZnO nanowires on indium tin oxide (ITO) film via a physical vapor method. The nanowire surface is then decorated with CdTe quantum dots by pulsed electron-beam deposition (PED). The nanowires alone provided a 20-fold increase in the short circuit current under visible light illumination. This was further increased by a factor of approximately 1.5 by the photosensitization effect of CdTe, which has an optical absorption of up to 820 nm.

Coculturing embryonic stem cells with damaged hepatocytes leads to restoration of damage and high frequency of fusion

Controversy surrounds issue of cell fusion as a repair mechanism whereby stem cells regenerate. To identify the ratio of fusion happens between stem cells and damaged cells, hepatic cells were damaged with 200microM H2O2 for 2 hr. Then, mouse ESCs were cocultured with damaged human hepatocytes. Fusion was detected directly by karyotyping after 48hr coculture as well as by Oct4 promoter drove GFP signal. Results showed that average ratio of fusion in undamaged control group was 0.031 per thousand while ratio of fusion in damaged group was 0.357 per thousand, which was 10 times higher than fusion happened in the control group. Meanwhile, GFP signal indicated that fusion induced hepatic cells' Oct-4 reactivation. Fusion derived hybrid cells contained chromosomes from both parental cells. Most of the chromosomes were from damaged human hepatic cells. Activity of damage-related enzymes LDH, SGOT and SGPT were significantly lower at 48hr coculture than at 12hr coculture. Expression of albumin in co-culture system was up-regulated after coculture, which indicated the reparation of damage after coculturing. Also, by applying RT-PCR and immunocytochemistry differentiation status of ES cells were evaluated. It was shown that ES cells differentiated to hepatic lineage cells and expressed hepatic genes and proteins.

Temporal trends in cause-specific late mortality among five-year survivors of childhood cancer

10004

Background: Five-year survival rates for childhood cancer have increased over the past 4 decades, increasing the number of long-term survivors. Among 5-yr survivors, the impact of changes in therapy on cause-specific late mortality has not been thoroughly assessed. Methods: Late mortality was evaluated over 3 eras (1974–81, 1982–90, 1991–2000) in 26,643 5-year survivors diagnosed <21 years of age from the SEER population-based registry. Cause-specific mortality was categorized as death from recurrence/progression of primary disease, external causes, and non-recurrence/non-external causes (Non-Recur/Ext) (i.e., deaths from health conditions including sequelae of cancer therapy). Results: All-cause and Recurrence mortality was significantly lower in more recent eras ( Table ). No significant improvement in late mortality attributable to Non-Recur/Ext causes was seen. Additionally, all-cause mortality was significantly lower in more recent eras for 5-year survivors of ALL, AML, Hodgkin, NHL, and CNS tumors, but not neuroblastoma and Ewing's Sarcoma where an increase in cumulative incidence of late mortality was seen in more recent eras. Significant improvement in late mortality from Recurrence by era was seen in most diagnostic groups. Conclusions: All-cause late mortality has improved with more recent eras, attributable to reduced rates of mortality from progression of primary disease (i.e., durable remission). Importantly, however, efforts to reduce the toxicity of more recent therapies have not produced detectable reduction in mortality attributable to other health conditions including sequelae of cancer therapy (non-Recur/Ext causes of death), which would include death from second malignancy, cardiac and pulmonary conditions. Worsening late mortality for 5-year survivors of neuroblastoma and Ewing's sarcoma may be due to improved use of salvage therapies that delay, but do not ultimately prevent death. [Table: see text]

No significant financial relationships to disclose.

Effect of berry size and sodium hydroxide pretreatment on the drying characteristics of blueberries under infrared radiation heating

This research studied the effect of berry size and dipping pretreatment in hot sodium hydroxide (NaOH) solution on the drying characteristics of blueberries under infrared radiation (IR) heating. Changes in the microstructure and diffusion coefficient of the berries after the NaOH pretreatment were also determined using scanning electronic microscopy and dynamic vapor sorption (DVS), respectively. To quantify the effect of berry size, non-pretreated bulk blueberries were sorted into 6 groups based on their diameters and dried at 70 degrees C. To determine the effectiveness of NaOH pretreatment in improving drying characteristics, bulk blueberries of different sizes, both nonpretreated and NaOH pretreated, were dried at constant temperatures of 80 and 90 degrees C, and variable temperatures of 70 degrees C for 50 min followed by 90 degrees C for 50 min. The NaOH pretreatment dipped blueberries in 0.1% NaOH solution with fruit to solution ratio 1:1 (w/v) at initial temperature of 93 degrees C for 5 s. Results showed that the drying rate increased with decreased berry size. Average moisture diffusivity was in the range of 5.89 to 8.13 m2/s at 70 degrees C. The NaOH pretreatment increased drying rate and moisture diffusivity and reduced the number of broken berries, especially at high drying temperatures. Results from SEM observation and DVS showed that the increase in diffusivity coefficients of berry coat and loss of intact microstructure in coat and tissue cells might contribute to the effect of NaOH pretreatment on the IR drying of blueberries.

Effects on human eyes caused by experimental exposures to office dust with and without addition of aldehydes or glucan

Thirty-six volunteers (in three susceptibility groups: 11 subjects were non-allergic with nasal histamine hypersensitivity, 13 were non-allergic with normal sensitivity, and 12 were pollen allergic with or without nasal hypersensitivity) were exposed for three and a half hours in a climate chamber. Each subject was exposed to clean air (dust 45 +/- 38 microg/m(3) total suspended particle, TSP), house dust at 357 +/- 180 microg/m(3) TSP, house dust 382 +/- 175 microg/m(3) TSP with added glucan (50 ng/m(3)) and house dust 394 +/- 168 microg/m(3) TSP with added aldehydes corresponding to a gaseous phase of 300 microg/m(3) in the air. The study was explorative by nature. No significant effects of exposures as such were seen on break-up time, conjunctival epithelial damage score and Trolox Equivalent Antioxidant Capacity (TEAC) in tear film and subjective ratings. However, in TEAC a significant different time course was seen during exposures to aldehyde-containing dust indicating a subacute and late response to the exposures. Perceived eye irritation increased significantly during exposures to normal dust. The perception ratings were highly correlated, whereas no correlation was found between the subjective responses and the objective measurements.

PRACTICAL IMPLICATIONS

The findings indicate that measurement effects on the eyes are rather insensitive measures of short time effects of office dust exposures.

Endoplasmic reticulum-associated calcium regulates taxol-induced apoptosis in breast cancer cells

Abstract #4163

Background: The body eliminates unhealthy cells through programmed cell-suicide called apoptosis. Calcium (Ca2+), one of the key regulators of cell survival, is also important in regulating apoptosis. Although the chemotherapeutic agent Taxol employs apoptosis to induce cell death in breast cancer treatment, the exact mechanism of how it induces apoptosis and the role of Ca2+ in this process remain unclear. The endoplasmic reticulum (ER), the main intracellular Ca2+ store, is newly-recognized as an important gateway in apoptosis, and possibly provides a target for Taxol.&#x2028; Objective/Hypothesis: Putting these facts together, our hypothesis is that ER Ca2+ changes induced by Taxol determine breast cancer cell susceptibility to apoptosis and thus play a key role in ER-associated apoptosis. Therefore, this study investigated whether Ca2+ changes, especially associated with the ER, were generated and related to this apoptotic event.&#x2028; Study Design and Methods: For this study, we used the MDA-MB-468 breast cancer cell line. The dynamic Ca2+ changes induced by Taxol were determined in living breast cancer cells by two methods: free cytosolic Ca2+ changes were measured using Fluo4-AM Ca2+ dye; and ER Ca2+ changes were measured by a novel Ca2+ cameleon, D1ER. After inducing and evaluating Taxol-induced apoptosis in this breast cancer cell line, the effects of different Ca2+ interfering agents on the apoptotic event were tested to determine whether Taxol-induced apoptosis is Ca2+ dependent.&#x2028; Results: Taxol has a direct effect on Ca2+ homeostasis. Taxol induces a rapid ER Ca2+ release and results in a transient increase in cytosolic Ca2+ levels. A gradual ER Ca2+ depletion developed and contributed to the final sustained cytosolic Ca2+ increase. Interfering with these Ca2+ changes inhibited the Taxol-induced apoptosis, indicating that ER Ca2+ promotes Taxol-induced apoptosis.&#x2028; Relevance: It is critical to understand the process through which the widely used anticancer agent Taxol induces apoptosis. This research addressed the question of whether intracellular Ca2+ changes play a critical or marginal role in mediating Taxol-induced apoptosis. Elucidating the role of calcium in this process will not only help to clarify the mechanism of Taxol, but also aid in more effective application of Taxol in breast cancer treatment.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4163.

Radiotherapeutic management of isolated local-regional recurrence following mastectomy

Abstract #5135

Background: Postmastectomy isolated local-regional recurrence(ILRR) remains a therapeutic challenge. This retrospective study aims to evaluate the role of radiotherapy(RT) in these patients and to analyze factors that influence local-regional control and survival.&#x2028; Methods: 255 pts with chest-wall(CW) and/or regional nodes recurrence(supraclavicular SC, axillary AXI and internal mammary nodes IMN) as first failure and received RT during 1990 and 2005 were analyzed, included 109 CW recurrence only, 114 regional nodes only and 32 pts with both, resulted in 304 recurrent sites. The median dose was 60Gy(47-74). Systemic treatment was give to 190 pts, including chemotherapy in 171, endocrine therapy(ET) in 69, and both in 41 pts.&#x2028; Results: The median disease-free interval(DFI) was 22 mo(2-260 mo), which were 37 and 17 mo in pts with positive hormonal receptor (HR) and negative HR respectively. Median follow-up was 45 mo (9 mo -15.5 yrs). The 2, 5 and 8-yr overall survival rate was 86.4%, 56.5% and 35% respectively. Median survival time after recurrence was 79 mo. The 2, 5 and 8-yr local control rate was 56.1%, 36.3% and 27.6% respectively. 79 second recurrence in the initial recurrent region and 83 subsequent recurrence in other local-regional sites were found.&#x2028; &#x2028; CW is the most common site of second recurrence. Multivariate analysis showed that no CW involvement, non-diffuse recurrence and radiation to the entire recurrent region were independent prognostic factors on local control of initial recurrent sites. ET proved to be the only independent prognostic factors on subsequent recurrence in other sites. In pts with CW recurrence, small field(67 pts) resulted in significantly lower 5-yrs local control compared to entire CW irradiation(74 pts) (33.6% vs 55.6%, p=0.023). Cox regression model found that DFI≥1yr, positive HR, solitary CW or non-supraclavicular nodal recurrence were independent favorable prognostic factors on overall survival .&#x2028; Conclusions: RT is an effective approach for ILRR after mastectomy. Radiation fields should cover the entire recurrent region. Elective irradiation to the CW in pts with nodal recurrence is recommended. Prognostic Index based on the positive multivariate analysis could be established as to stratify different prognostic sub-groups.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5135.

Association between nucleotide excision repair gene polymorphisms and chromosomal damage in coke-oven workers

The associations between several genetic polymorphisms of nucleotide excision repair genes (NER) and chromosome damage level were studied among 140 coke-oven workers exposed to a high level of polyaromatic hydrocarbons (PAHs) and 66 non-exposed workers. Seven polymorphisms with functional potential in five NER genes (ERCC1, ERCC2, ERCC4, ERCC5 and ERCC6) were genotyped in the 206 study subjects. Multivariate analysis of covariance revealed that coke-oven workers with the ERCC1 19007 CC genotype had significantly higher cytokinesis-block micronucleus frequency (CBMN) (10.5 +/- 6.8 per thousand) than those with CT (8.1 +/- 6.6 per thousand, p = 0.01) or TT (6.6 +/- 3.7-/ per thousand p = 0.05) or CT+TT genotypes (7.5 +/- 6.3 per thousand, p = 0.004). The ERCC6 A3368G polymorphism was also associated with CBMN frequency among coke-oven workers. Subjects with the AA genotype have a significantly higher CBMN frequency (10.0 +/- 6.9 per thousand) than those with AG (6.7 +/- 4.2 per thousand, p = 0.05) or AG+GG genotypes (6.6 +/- 4.1 per thousand, p = 0.02). Stratification analysis revealed the significant associations between ERCC1 C19007T and ERCC6 A3368G, and the CBMN frequencies were only found among older workers. In addition, a significant association between ERCC2 G23591A polymorphism and CBMN frequencies was also found among older coke-oven workers. The results suggest that polymorphisms of ERCC1 C19007T, ERCC6 A3368G and ERCC2 G23591A are associated with the CBMN frequencies among coke-oven workers.

Selective hepatic vascular exclusion and Pringle maneuver: a comparative study in liver resection

OBJECTIVE

Most liver resections require champing of the hepatic pedicle (Pringle maneuver) to avoid excessive blood loss. But Pringle maneuver cannot control backflow bleeding of the hepatic vein. Resection of liver tumors involving hepatic veins may cause massive hemorrhage or air embolism from injuries of the hepatic vein. Although total hepatic vascular exclusion (THVE) can prevent bleeding of the hepatic vein effectively, it also may result in systemic hemodynamic disturbance because of the clamped inferior vena cava (IVC). SHVE, a new technique, can control the inflow and outflow of the liver without clamping the vena cava. We compared the effects of selective hepatic vascular exclusion (SHVE) and Pringle maneuver in resection of liver tumors involving the junction of the hepatic vein.

METHODS

From January 2000 to October 2005, 2100 patients with liver tumors had undergone liver resections in our department. Among them, tumors of 235 cases adhered to or were close to the junction of one or more hepatic veins. Both SHVE and Pringle maneuver were used to control blood loss during hepatectomy. These 235 cases were divided into two groups: Pringle maneuver group (110) from January 2000 to December 2002 and SHVE group (125) from January 2003 to October 2005. Data were analyzed regarding the intraoperative and postoperative courses of the patients. In the SHVE group, total SHVE (clamping the porta hepatis and all major hepatic veins) was used in 69 cases and partial SHVE (clamping the porta hepatic and one or two hepatic veins) in 56 cases. There were three methods in hepatic veins occlusion: ligating with suture, encircling and occluding with tourniquets and clamping with Satinsky clamps.

RESULTS

There was no difference between the two groups regarding the age, gender, tumor size, cirrhosis and HBsAg rate, ischemia time and operating time. Intraoperative blood loss and transfusion requirements were significantly decreased in the SHVE group. Hepatic veins rupture with massive blood loss occurred in 14 and air embolism in three during the tumor resection, but there was no massive blood loss and air embolism in the SHVE group due to hepatic vein occlusion. Postoperative bleeding, reoperation, liver failure and mortality rate were higher, and ICU stay and hospital stay were longer in the Pringle group than those in the SHVE group.

CONCLUSION

SHVE is much more effective than Pringle maneuver in controlling intraoperative bleeding. It can prevent massive blood loss and air embolism from hepatic veins rupture and can reduce the postoperative complication rate and mortality rate. Clamping the hepatic veins with Satinsky clamps is much safer and easier than ligating with suture and occluding with tourniquets.

Identification and characterization of the NTPase activity of classical swine fever virus (CSFV) nonstructural protein 3 (NS3) expressed in bacteria

The nonstructural protein 3 (NS3) of members of the family Flaviviridae possesses multiple enzyme activities that are likely to be essential for viral replication. Here, we cloned and expressed full-length CSFV NS3 protein (NS3FL) and its N-terminal truncated version (ntNS3) in E. coli. NTPase activities of the purified NS3FL and ntNS3 proteins and their reaction conditions were investigated. The results showed that CSFV NS3FL and ntNS3 proteins contained a specific polynucleotide-stimulated NTPase acitivity. Characterization of ntNS3 NTPase activity showed that optimal reaction conditions with respect to pH, MgCl2 and monovalent cations were similar to those of bovine viral diarrhea virus (BVDV) and hepatitis C virus (HCV). Site-directed mutagenesis analysis demonstrated that the GxGK(232)T to GxGAT mutation in the conserved motif I abolished the NTPase activity of ntNS3, whereas substitution of TATPA(354) for TATPV in the motif III had no effect on the enzyme activity. Moreover, the kinetic properties (K(m) and k(cat)) of CSFV NS3 were more similar to those of BVDV. Our results provide insight into the structure-function relationship of CSFV NS3 and facilitate our understanding of its role in the replication cycle of CSFV.

Long-Term Prediction of Soybean Rust Entry into the Continental United States

This special report demonstrates the feasibility of long-term prediction of intercontinental dispersal of Phakopsora pachyrhizi spores, the causal agent of the devastating Asian soybean rust (SBR) that invaded the continental United States in 2004. The climate-dispersion integrated model system used for the prediction is the combination of the particle transport and dispersion model (HYSPLIT_4) with the regional climate prediction model (MM5). The integrated model system predicts the trajectory and concentration of P. pachyrhizi spores based on three-dimensional wind advection and turbulent transport while incorporating simple viability criteria for aerial spores. The weather input of the model system is from a seasonal global climate prediction. The spore source strength and distribution were estimated from detected SBR disease severity and spread. The model system was applied to the known P. pachyrhizi spore dispersal between and within continents while focusing on the disease entry into the United States. Prediction validation using confirmed disease activity demonstrated that the model predicted the 2004 U.S. entry months in advance and reasonably forecast disease spread from the south coast states in the 2005 growing season. The model also simulated the dispersal from Africa to South America and from southern South America to Columbia across the equator. These validations indicate that the integrated model system, when furnished with detailed source distribution, can be a useful tool for P. pachyrhizi and possibly other airborne pathogen prediction.

Engineering of Bacillus subtilis for enhanced total synthesis of folic acid

We investigated whether the yield of the B vitamin folic acid could be elevated in Bacillus subtilis. Strategies for increasing the folic acid yield were investigated by employing computer-aided flux analysis and mutation. Controlling the activity of the enzyme pyruvate kinase by placing it under inducible control was one strategy devised to elevate yield while insuring that a rapid growth rate results. Other single mutation strategies included amplifying the expression of the genes in the folate operon and overexpressing the Escherichia coli aroH gene, which encodes 2-dehydro-3-deoxyphosphoheptonate aldolase. The latter could conceivably elevate the abundance of the folic acid precursor, para-aminobenzoic acid. Strains that combined two or more mutations were also constructed. Overall, a strain possessing inducible pyruvate kinase, overexpressed aroH, and increased transcription and translation of genes from the folic operon exhibited the best yield. The yield was eightfold higher than that displayed by the parent B. subtilis 168 strain.

SEB combined with IL-1ra could prolong the survival of the rat allografts in high-risk corneal transplantation

PURPOSE

To determine whether the superantigen Staphylococcal enterotoxin B (SEB) combined with interleukin-1 receptor antagonist (IL-1ra) prolong allograft survival better than individual agents in high-risk corneal transplantation in a rat model.

METHODS

Fisher 344 donor corneas were transplanted into Lewis recipients. High-risk transplantation meant that the transplants were sutured into the recipient beds with corneal neovascularization induced by placing three interrupted sutures in the host cornea. All of the recipients were divided in blinded fashion into four groups. Group I was injected with saline buffer. Group II was injected intraperitoneally with 0.2 mL SEB (75 microg/kg) at 4-day intervals on three occasions before transplantation. Group III was injected with 0.1 mL IL-1ra (1 mg/mL) subconjunctivally from the first day after transplantation for 2 weeks. Group IV received both SEB and IL-1ra. All transplants were evaluated for signs of rejection for 4 weeks after surgery. Ten days after transplantation, two recipients in each group were sacrificed for histopathological and immunological evaluation.

RESULTS

The mean survival time of the allografts in the control group was 5.89 +/- 0.79 days; in SEB group, 10.70 +/- 2.52 days; in IL-1ra group, 8.25 +/- 0.71 days; in the SEB and IL-1ra group, 17.36 +/- 2.39 days. CD4+ and CD8+ lymphocyte infiltration into the allografts and the percentage of the lymphocytes in the spleen and mandibular lymphatic nodes was significantly decreased among the treated groups with dampened lymphocyte reactivity. The SEB plus IL-1ra combination group showed the strongest inhibition.

CONCLUSION

SEB and IL-1ra are most effective in combination to treat high-risk corneal transplants.

Assessment of Epidemic Potential of Soybean Rust in the United States

This article assesses the epidemic potential of soybean rust (Phakopsora pachyrhizi) in the United States. In the assessment, there are three critical components of uncertainty: (i) suitability of climate conditions in production areas for soybean rust epidemics; (ii) likelihood of establishment of the fungus in North America; and (iii) the seasonal dispersal potential of the pathogen from overwintering regions to major soybean production regions. Assessments on the first and second components suggest soybean rust epidemics are likely in the United States, and the certainty of the third component is yet to be determined. Comparison of epidemiological factors for soybean rust in soybean production regions between China and the United States shows a complicated picture with the United States having factors that both increase and decrease risk. Future investigation of risk components-incipience in the field and long-distance dispersal-is needed.

Surface-enhanced Raman spectroscopy using silver-coated porous glass-ceramic substrates

Surface-enhanced Raman scattering (SERS) has been studied using a silver-coated porous glass-ceramic material as a new type of substrate. The porous glass-ceramic is in the CaO-TiO2-P2O5 system prepared by controlled crystallization and subsequent chemical leaching of the dense glass-ceramic, leaving a solid skeleton with pores ranging in size from 50 nm to submicrometer. Silver was coated on the surface of the porous glass-ceramic by radio frequency (RF) sputtering or e-beam evaporation in vacuum. SERS spectra of excellent quality were obtained from several dyes and carboxylic acid molecules, including rhodamine 6G, crystal violet, isonicotinic acid, and benzoic acid, using this new substrate. This new substrate showed a good compatibility with these molecules. The porous glass ceramic with a nanometer-structured surface accommodated both test molecules and silver film. The absorbed molecules were therefore better interfaced with silver for surface-enhanced Raman scattering.

Non-specific tolerance induced by staphylococcal enterotoxin B in treating high risk corneal transplantation in rats

AIMS

To explore the role of staphylococcal enterotoxin B (SEB) in treating high risk corneal keratoplasty in rats.

METHODS

Rat corneal high risk transplantation rejection models were set up using Fisher 344 and Lewis rats. The experimental rats were injected intraperitoneally with 0.2 ml SEB at different concentrations before keratoplasty. The rejection indexes of the allograft were recorded and the lymphocyte infiltration in the allograft and the percentage of the lymphocyte subpopulation in the lymphatic organs were also examined. Lymphocyte proliferation ability and the concentration of IL-2 and IL-10 in the serum were also evaluated.

RESULTS

Compared with the control group, SEB prolonged the survival time of the allograft significantly from 7 to 12 days. It could also reduce CD4(+) and CD8(+) lymphocyte infiltration in the allograft and minimise the percentage of CD4(+) and CD8(+) lymphocytes in the lymphatic organs. The lymphocyte proliferation ability was also weakened. However, the percentage of CD4(+) NK T lymphocytes in the lymphatic organs was raised. The serum concentration of IL-10 was higher but IL-2 was lower in the SEB treated groups.

CONCLUSIONS

SEB prolonged the survival time of the allograft in high risk rat corneal allo-transplantation, which may be caused by T cell deletion and acquisition of non-specific tolerance.

A convenient and rapid sample repositioning approach for atomic force microscopy

A novel repositioning approach is described for repeated observations of a specimen at a close proximal location in the atomic force microscope. The approach is similar to keystone architecture, whereby the repositioning is achieved by forming a male structured base for the specimen, and a corresponding female counterpart as the frame. For the combination of an acrylic acid frame and a metal base, 90% translation shifts are less than 10 microm, and almost all angular disorientations are within +3 degrees to -3 degrees . Nanometre-scale surface features can be relocated easily and reliably even after 40 imaging-removal-imaging cycles, dipping the specimen in solutions or heating up to 500 degrees C.

Enterovirus replication in valvular tissue from patients with chronic rheumatic heart disease

AIMS

To investigate the involvement of enterovirus infection in chronic, rheumatic heart disease.

METHODS AND RESULTS

Formalin-fixed, paraffin-embedded, surgical samples of valve tissue were examined for the presence of enteroviral RNA and virus capsid protein VP1 by in situ hybridization and immunostaining. Of 53 cases, 33 were patients with chronic rheumatic heart disease and 20 had Marfan's syndrome or degenerative valve disease. Enterovirus RNA was detected in 8 (24.2%) of 33 patients with chronic rheumatic heart disease by in situ hybridization using strand-specific oligonucleotide probes, complementary to conserved sequences in enterovirus genomic (positive strand) RNA. The replication template (negative strand) RNA also was found in seven of these eight cases. The viral capsid protein VP1 was detected in 16 (48.5%) of 33 patients with chronic rheumatic heart disease by immunohistochemistry and correlated with viral RNA detection. Virus was localized generally to valvular tissue. Neither viral RNA nor capsid protein VP1 were found in valvular tissue from any of the 20 comparison cases.

CONCLUSIONS

This is the first demonstration of detection and localization of both enterovirus RNA and capsid protein in chronic rheumatic heart disease. The presence of negative strand RNA and VP1 indicates enteroviral RNA replication and protein synthesis and suggests an aetiological role of enterovirus in the pathogenesis of chronic rheumatic heart disease.

RyR3 amplifies RyR1-mediated Ca(2+)-induced Ca(2+) release in neonatal mammalian skeletal muscle

The neonatal mammalian skeletal muscle contains both type 1 and type 3 ryanodine receptors (RyR1 and RyR3) located in the sarcoplasmic reticulum membrane. An allosteric interaction between RyR1 and dihydropyridine receptors located in the plasma membrane mediates voltage-induced Ca(2+) release (VICR) from the sarcoplasmic reticulum. RyR3, which disappears in adult muscle, is not involved in VICR, and the role of the transiently expressed RyR3 remains elusive. Here we demonstrate that RyR1 participates in both VICR and Ca(2+)-induced Ca(2+) release (CICR) and that RyR3 amplifies RyR1-mediated CICR in neonatal skeletal muscle. Confocal measurements of intracellular Ca(2+) in primary cultured mouse skeletal myotubes reveal active sites of Ca(2+) release caused by peripheral coupling between dihydropyridine receptors and RyR1. In myotubes lacking RyR3, the peripheral VICR component is unaffected, and RyR1s alone are able to support inward CICR propagation in most cells at an average speed of approximately 190 microm/s. With the co-presence of RyR1 and RyR3 in wild-type cells, unmitigated radial CICR propagates at 2,440 microm/s. Because neonatal skeletal muscle lacks a well developed transverse tubule system, the RyR3 reinforcement of CICR seems to ensure a robust, uniform, and synchronous activation of Ca(2+) release throughout the cell body. Such functional interplay between RyR1 and RyR3 can serve important roles in Ca(2+) signaling of cell differentiation and muscle contraction.

[Biological stabilities and identification of a highly metastatic subpopulation from a human osteosarcoma cell line]

OBJECTIVE

To investigate the biological stabilities and the identification of a human highly metastatic osteosarcoma subpopulation.

METHODS

Tumor pieces of the cell were inoculated into nude mice orthotopically. Lung node metastatic foci were obtained by culturing, the procedure was repeated for 3 cycles. Changes were observed in intra-tibial tumor growth, pulmonary metastatic rate in vivo, morphological characteristics, expressions of BMP, vimentin, actin, NEC and karyotype analyses of every passage in vitro.

RESULTS

The intra-tibial tumor growth rates were 100%, the proliferation abilities were stable, and the pulmonary metastatic rates were higher than 80%. The expressions of BMP, vimentin, actin were positive, but the expression of NSE was negative. Its morphological characteristics the antigen-positive substances and karyotype were similar to those observed in human osteosarcoma.

CONCLUSION

SOSP-M1 with very stable biological characteristics is a good model for the study of human osteosarcoma.

[The 5-year death analysis in patients with nasopharyngeal carcinoma treated with radiotherapy]

OBJECTIVE

To study the main death cause of nasopharyngeal carcinoma (NPC) treated with radiotherapy for 5 years.

METHOD

An analysis had been made to evaluated the 5-year death in 165 patients with NPC treated with radiotherapy.

RESULT

The death correlates strongly with the clinical stage, type and radiation dose (P < 0.05).

CONCLUSION

The distant metastasis and local recurrence are the main death cause of NPC.

[Acidity and acid buffering capacity of aerosols during sand-dust storm weather in Beijing]

In the spring of 2000, there were 12 sand-dust storms in Beijing. 2 sand-dust storms were experienced in time and mass concentrations, elementary concentrations acidity and acidic buffering capacity of TSP(Total Suspended Particulate, < 100 microns) and PM10(Inhalable particulate, < 10 microns) were sampled and analyzed. Results showed that pollution level of aerosols was extremely high. However, the acidity of aerosols was relatively low and the aerosols had very strong acid buffering capacity for acidification. Therefore, the aerosols brought about by the sand-dust storms could avoid the occurrence of acidic precipitation to some extent.

Synergistic movements of Ca(2+) and Bax in cells undergoing apoptosis

Apoptosis is a physiological counterbalance to mitosis and plays important roles in tissue development and homeostasis. Cytosolic Ca(2+) has been implicated as a proapoptotic second messenger involved in both triggering apoptosis and regulating cell death-specific enzymes. A critical early event in apoptosis is associated with the redistribution of Bax from cytosol to mitochondria and endoplasmic reticulum (ER) membranes; however, the molecular mechanism of Bax translocation and its relationship to Ca(2+) is largely unknown. Here we provide functional evidence for a synergistic interaction between the movements of intracellular Ca(2+) and cytosolic Bax in the induction of apoptosis. Overexpression of Bax in cultured cells causes a loss of ER Ca(2+) content. Depletion of ER Ca(2+) through activation of the ryanodine receptor enhances the participation of Bax into the mitochondrial membrane. Neither Bax translocation nor Bax-induced apoptosis is affected by buffering of cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid, suggesting that depletion of ER Ca(2+) rather than elevation of cytosolic Ca(2+) is the signal for cell apoptosis. This dynamic interplay of Ca(2+) and Bax movements may serve as an amplifying factor in the initial signaling steps of apoptosis.

Regulation of KChIP2 potassium channel beta subunit gene expression underlies the gradient of transient outward current in canine and human ventricle

Expression of four members of the KChIP family of potassium channel beta subunits was examined in canine heart. Only one member of the gene family, KChIP2, was expressed in heart. There was a steep gradient of KChIP2 mRNA expression across the canine ventricular free wall. KChIP2 mRNA was 25-fold more abundant in the epicardium than in the endocardium, and this gradient paralleled the gradient in transient outward current (Ito) expression. In contrast, Kv4.3 potassium channel alpha subunit mRNA was expressed at equal levels across the ventricular wall. There was no difference in the pharmacological sensitivity of epicardial and endocardial Ito channels to flecainide, suggesting that the current is produced by the same channel in the two tissues. A similar gradient of KChIP2 expression was found across the ventricular wall of human heart, but not rat heart. It is concluded that transcriptional regulation of the KChIP2 beta subunit gene, rather than the Kv4.3 [alpha] subunit gene, is the primary determinant regulating the transmural gradient of Ito expression in the ventricular free wall of canine and human heart.

[An experimental study on subconjunctival interleukin-1 receptor antagonist for promotion of corneal transplant survival]

OBJECTIVE

To determine whether the subconjunctival application of interleukin-1 receptor antagonist (IL-1ra) can prolong the corneal graft survival in the rat model of orthotopic penetrating keratoplasty.

METHODS

For all experiments, F344 corneas were transplanted into LOU (major histocompatibility-disparate) eyes. Experimental groups received subconjunctival injection of 50, 100 and 200 microg IL-1ra respectively, and the control group received the same volume of 0.9% normal saline instead for consecutive 2 weeks. All transplants were evaluated for 4 weeks after surgery for signs of rejection.

RESULTS

The mean survival time (MST) of the grafts of the experimental groups was increased significantly (t = 0.00, P < 0.01) in comparison with the control group. The MST of the IL-1ra 200 microg group was increased significantly than that of the IL-1ra 50 microg group (t = 0.00, P < 0.01). Furthermore, the IL-1ra-treated grafts had significantly less corneal inflammation, infiltration, lower levels of opacity, edema, neovascularization and rejection index compared with the control group.

CONCLUSIONS

Subconjunctival treatment of IL-1ra has a significantly positive effect on promoting corneal allograft survival. And its effect is dosage-dependent.

MinK-related peptide 1: A beta subunit for the HCN ion channel subunit family enhances expression and speeds activation

The HCN family of ion channel subunits underlies the currents I(f) in heart and I(h) and I(q) in the nervous system. In the present study, we demonstrate that minK-related peptide 1 (MiRP1) is a beta subunit for the HCN family. As such, it enhances protein and current expression as well as accelerating the kinetics of activation. Because MiRP1 also functions as a beta subunit for the cardiac delayed rectifier I(Kr), these results suggest that this peptide may have the unique role of regulating both the inward and outward channels that underlie cardiac pacemaker activity. The full text of this article is available at http://www.circresaha.org.

Computerized planimetry versus clinical assessment for the measurement of cervical ectopia

OBJECTIVE

As part of a study to assess the role of cervical ectopia in the acquisition of cervical infections, we determined the reliability of cervical ectopia measurements made by computer planimetry and by clinical (visual) assessment.

STUDY DESIGN

We conducted pelvic examinations of 1004 women seeking contraceptive services at two health centers in Baltimore. After application of acetic acid, clinicians estimated the relative area of ectopia by visual inspection and took cervical photographs. Two independent raters measured the absolute and relative areas of ectopia from the digitized images by means of an analytic software program. Agreement levels between raters, between multiple readings by the same rater, and between the two measurement methods were quantified by means of the intraclass correlation coefficient and weighted kappa.

RESULTS

Intrarater agreement was excellent for computer planimetry measurements of the absolute (intraclass correlation coefficient, 0.97) and relative (intraclass correlation coefficient, 0.89) areas of ectopia. Interrater agreement was also high for computer planimetry measurements of the absolute (intraclass correlation coefficient, 0.83) and relative (intraclass correlation coefficient, 0.85) areas of ectopia. Agreement levels were moderate between clinician assessment and computer planimetry measurements of the relative area of ectopia (kappa = 0.48), but agreement was better when clinical assessment was limited to observations by a single, experienced clinician.

CONCLUSION

Measurement of cervical ectopia by computer planimetry was highly reliable and appears appropriate for assessment of the role of ectopia in the acquisition of cervical infections. Clinical assessment of cervical ectopia may be used when computer planimetry is not available.

Simultaneous quantitative UV spectrophotometric determination of multicomponents of amino acids using linear neural network

Simultaneous determination of multicomponents of six amino acids with a novel chemometric technique-a linear neural network (LNN) algorithm is reported in this study. Based on the data correlation coefficient and standard deviation method, 17 representative wavelength points are selected from the original UV spectral data (343 points) as the original input patterns for LNN to build a neural network model. The results obtained only by iterating 15 times is satisfying, with a correlation coefficient of 0.999 and a relative small standard deviation.