Room temperature hydrogen detection using 1-D nanostructured tin oxide sensor

Room temperature sensing of hydrogen using randomly oriented tin oxide nanowires has been demonstrated successfully. The role of surface functionalization of nanowires with platinum catalyst in rapid hydrogen detection is also studied. These nanowires were successfully incorporated into a micro-electro-mechanical (MEMS) device. The device can successfully detect hydrogen gas (as low as 500 ppm) with response time as low as 10 sec. Effect of aspect ratio of the nanowires on diffusion of hydrogen molecules in the tin oxide nanowires is elucidated in detail.

Explaining age-specific inequalities in mortality from all causes, cardiovascular disease and ischaemic heart disease among South Korean male public servants: relative and absolute perspectives

OBJECTIVE

To examine age-specific patterns in the ability of major cardiovascular risk factors to explain relative and absolute socioeconomic inequalities in mortality from all causes, cardiovascular disease (CVD), and ischaemic heart disease (IHD).

DESIGN

Prospective cohort study.

SETTING

South Korea.

SUBJECTS

575 377 male public servants aged 30-64 with 16 998 deaths between 1995 and 2003.

MAIN OUTCOMES

All-cause, CVD, and IHD mortality.

RESULTS

Four cardiovascular risk factors (cigarette smoking, blood pressure, fasting serum glucose, and serum total cholesterol) were significantly associated with mortality risk. Changing relationships in socioeconomic distribution of risk factors with age were observed. The magnitude of reduction in percent change in absolute risk was greater than that in relative risk. While the risk factors explained only 15.2% of excess RR for all-cause mortality in low-income men aged 30-44, the absolute excess risk of all-cause mortality was reduced by 48.3% when the risk factors were removed from the whole population. This pattern was generally true for all causes, CVD, and IHD, and true for all age groups and risk factors examined. Cigarette smoking and hypertension were the leading contributors in explaining relative and absolute inequality in mortality.

CONCLUSION

Policy efforts to eliminate major cardiovascular risk factors in the general population may have a significant effect on reducing the absolute burden of socioeconomic inequality in mortality. Policy efforts to attenuate socioeconomic inequality in cardiovascular risk factors need to be directed to younger age groups in South Korea.

Expression of brain-derived neurotrophic factor in the rat forebrain and upper brain stem during postnatal development: an immunohistochemical study

The present study was undertaken to characterize the regional and temporal patterns of brain-derived neurotrophic factor (BDNF) in the rat forebrain and upper brain stem during postnatal development using an immunohistochemical approach. Results indicated that BDNF-immunoreactive (IR) cells could be divided into three groups based on their postnatal developmental patterns: (group 1) BDNF-IR cells were first detected between postnatal days (PND) 1 and 7, and thereafter they increased in number and remained stable during later stages of ontogeny; (group 2) BDNF-IR cells progressively increased in number with age, and then decreased in adults; (group 3) numerous BDNF-IR cells detected between PND 1 and 7 showed a dramatic reductions in number with few IR cells in adults. In contrast, the developmental pattern of most BDNF-IR fibers differed from that of IR neurons, i.e. they appeared between PND 1-28 and thereafter continued to increase in number showing a maximum level in adults. Additionally, BDNF-IR cells in the superficial layer of the neocortex and IR fibers in the stratum oriens of CA2 first appeared as late as PND 28 and in adults, respectively. After colchicine treatment, reexpression or a marked increase in the number of BDNF-IR neurons was observed in many areas of the adult brain where a progressive decrease in BDNF-IR cell numbers during development and scant or some IR neurons in adults were shown. These results showed both transient and persistent expression of BDNF in various regions of the developing rat brain.

A micromachined electrochemical sensor for free chlorine monitoring in drinking water

In this work, we designed, fabricated and tested a disposable, flow-through amperometric sensor for free chlorine determination in water. The sensor is based on the principle of an electrochemical cell. The substrate, as well as the top microfluidic layer, is made up of a polymer material. The advantages include; (a) disposability from low cost; (b) stable operation range from three-electrode design; (c) fluidic interconnections that provide on line testing capabilities; and (d) transparent substrate which provides for future integration of on-chip optics. The sensor showed a good response and linearity in the chlorine concentration ranging from 0.3 to 1.6 ppm, which applies to common chlorination process for drinking water purification.

Population-based and family-based studies on the serotonin transporter gene polymorphisms and bipolar disorder: a systematic review and meta-analysis

The serotonin transporter (5-HTT) is a candidate gene for bipolar disorder (BPD). It has been investigated for association with the illness in a series of studies, but overall results have been inconsistent and its role in the disorder remains controversial. Systematic reviews using meta-analytical techniques are a useful method for objectively and reproducibly assessing individual studies and generating combined results. We performed two meta-analyses of published studies--both population-based and family-based studies--investigating the association between BPD and the 5-HTT gene-linked polymorphic region (5-HTTLPR) and the intron 2 variable numbers of tandem repeats (VNTR) polymorphisms. The literature was searched using Medline and Embase to identify studies for inclusion. We statistically joined population-based and family-based studies into a single meta-analysis. For both polymorphisms, our review revealed significant pooled odds ratios (ORs): 1.12 (95% CI 1.03-1.21) for the 5-HTTLPR and 1.12 (95% CI 1.02-1.22) for the intron 2 VNTR. Meta-regression showed that neither the study type (population-based vs family-based; P=0.41 for the 5-HTTLPR and P=0.91 for the intron 2 VNTR) nor the sample ethnicity (Caucasian vs non-Caucasian; P=0.35 for the 5-HTTLPR and P=0.66 for the intron 2 VNTR) significantly contributed to the heterogeneity of the meta-analyses. The observed ORs could be regarded simply as a very small but detectable effect of the 5-HTT, which has an additive effect when combined with other susceptibility loci. Alternative hypotheses on this finding were also discussed: a stronger effect of the haplotypes involving the two polymorphisms or other SNP markers; a more direct effect of these polymorphisms on specific phenotypes of BPD; and the presence of gene-environment interaction as a mediator of the genetic effects of 5-HTT.

Trends in socio-economic differentials in cigarette smoking behaviour between 1990 and 1998: a large prospective study in Korean men

OBJECTIVES

To investigate the magnitude and time trends in socio-economic differentials in cigarette smoking behaviour.

STUDY DESIGNS

A prospective observational study of male civil servants followed-up for 8 years.

SETTING

All civil service offices in Korea.

PARTICIPANTS

A total of 322,991 male civil servants aged 30-49 years on whom information on monthly salary was available and who had reported cigarette smoking behaviour between 1990 and 1998.

RESULTS

Smoking prevalence was 60.1% in 1990 and was inversely associated with salary level. The difference in smoking prevalence between the highest and the lowest salary groups gradually widened from 13.0% in 1990 to 16.1% in 1998. The relative index of inequality (RII) as a measure of socio-economic inequality in smoking behaviour was 1.91 [95% confidence interval (CI) 1.86-1.97] in 1990 and increased between 1990 and 1998. The RII for smoking cessation was 0.60 in 1990 (95% CI 0.58-0.62) and gradually decreased as time lapsed.

CONCLUSIONS

An increasing trend in socio-economic inequality in smoking behaviour was observed in this study.

Alpha-difluoromethylornithine, ornithine decarboxylase inhibitor, antagonizes H2O2-induced cytotoxicity in HL-60 leukemia cells: regulation of iron-dependent lysosomal damage

Recent studies indicate that reactive oxygen species, such as H2O2, can be generated by anti-cancer drugs, can damage cells, and then induce apoptotic cell death. In this study, we reported whether polyamines were capable of affecting apoptotic cell death triggered by H2O2 in leukemia cells or not. Alpha-difluoromethylornithine treatment (DFMO, 3 mmol/L, 48 h), which depletes intracellular putrescine by inhibiting ornithine decarboxylase, reduced H2O2-induced cell death in the HL-60 leukemia cells. Cytotoxicity caused by H2O2 in putrescine-depleted cells was 50% lower than that in the control cells, as determined by propidium iodide, the annexin V and DNA fragmentation assays. Following putrescine (1 mmol/L) supplement, cell death induction caused by H2O2 was restored to a similar level as the DFMO-untreated control cells. It seems that this partly resulted from the intralysosomal iron-dependent oxidation of the cells because DFMO did not significantly affect the increment of enzymes related to oxidative-stress resistance. Putrescine depletion by DFMO treatment reduced the cellular iron uptake of the cells by about 70%. In parallel to the reduction of iron uptake, lysosomal damage (assayed by acridine orange relocalization or uptake test) in the DFMO-treated cells was far less than that in the control cells. Moreover, putrescine supplement also restored the iron uptake to the control cell levels. Pre-incubation with desferrioxamine (DFO), which chelates iron and forms a non-reactive Fe-DFO complex that is localized in the lysosomal compartment, inhibited H2O2-induced cell death. This work suggests that polyamines may play a critical role in apoptotic cell death triggered by H2O2 via the regulation of the iron-dependent instability of the lysosome.

Prescription behaviours of office-based doctors to standardized common cold patients in Korea

PURPOSE

To investigate real pictures of prescription behaviours of office-based doctors in Korea, especially focusing on the prescription of oral antibiotics and injections.

METHODS

Prescription information was collected from 18 standardized patients (SPs) with the symptoms of the common cold who visited doctors' office.

RESULTS

For these patients antibiotics were prescribed by 96 doctors (64.7%) out of 148 and the rate of antibiotic prescription increased with age of doctors, increasing number of medicines, and cost of medicines. Analgesics were most frequently prescribed (91.8%), and gastrointestinal drugs (81.6%), antitussivies (61.2%), antithistamines (61.2%), decongestants (59.2%), mucolytics (51.0%) and proteolytic enzymes (32.7%) followed. More than half of the doctors intended to give injections to the patients, which was higher among internists and doctors prescribed more medicines.

CONCLUSIONS

Antibiotics and injections were frequently prescribed for mild common colds in Korea. Action to ensure judicious use of antibiotics and injection is urgent.

Chronic fatigue among bank workers in Brazil

The present study examines the prevalence of chronic fatigue (CF) among bank workers in Brazil and possible associations with gender and working conditions. The study sample included all 735 workers from the department of data processing of a state bank. CF was assessed using the Chalder Fatigue Scale. Working conditions and socio-demographic, socio-economic and psychosocial factors at work were analysed. Psychiatric symptoms were measured with the SRQ-20. The overall estimate of the prevalence of CF was 8.7% [95% confidence intervals (95% CI) = 6.4-10.9%]: 7.8% (95% CI = 5.5-10.7%) among men and 11.0% (95% CI = 6.7-16.9%) among women. The male-female difference was not statistically significant, even after adjusting for minor psychiatric disorders. The overall prevalence of CF without minor psychiatric disorders was 4.5% (95% CI = 2.7-6.3%): 3.9% (95% CI = 1.9-5.9%) among men and 6.4% (95% CI = 2.0-10.1%) among women. In the final model, risk factors for CF were fast work speed [odds ratio (OR) = 3.5], dissatisfaction at work (OR = 3.1), minor psychiatric disorders (OR = 6.8), and medium (OR = 1.8) and heavy domestic workload (OR = 12.0). CF is common among these bank workers and is associated with psychosocial factors at work. Particularly among women, domestic workload, marital status and the presence of young children were associated with CF in the stratified analysis. Domestic workload may add physical and mental stress, putting employees at risk for CF from overload, or CF may cause workers to perceive domestic work as heavy.

Expression of brain-derived neurotrophic factor in rat dorsal root ganglia, spinal cord and gracile nuclei in experimental models of neuropathic pain

Chronic constriction injury of the sciatic nerve and lumbar L5 and L6 spinal nerve ligation provide animal models for pain syndromes accompanying peripheral nerve injury and disease. In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat L4 and L5 dorsal root ganglia (DRG) and areas where afferents from the DRG terminates (the L4/5 spinal cord and gracile nuclei) in these experimental models of neuropathic pain. Chronic constriction injury induced significant increase in the percentage of small, medium and large BDNF-immunoreactive neurons in the ipsilateral L4 and L5 DRG. Following spinal nerve ligation, the percentage of large BDNF-immunoreactive neurons increased significantly, and that of small BDNF-immunoreactive neurons decreased markedly in the ipsilateral L5 DRG, while that of BDNF-immunoreactive L4 DRG neurons of all sizes showed marked increase. Both chronic constriction injury and spinal nerve ligation induced significant increase in the number of BDNF-immunoreactive axonal fibers in the superficial and deeper laminae of the L4/5 dorsal horn and the gracile nuclei on the ipsilateral side. Considering that BDNF may modulate nociceptive sensory inputs and that injection of antiserum to BDNF significantly reduces the sympathetic sprouting in the DRG and allodynic response following sciatic nerve injury, our results also may suggest that endogenous BDNF plays an important role in the induction of neuropathic pain after chronic constriction injury and spinal nerve ligation. In addition, the increase of BDNF in L4 DRG may contribute to evoked pain which is known to be mediated by input from intact afferent from L4 DRG following L5 and L6 spinal nerve ligation.

Changes in voltage-gated calcium channel alpha(1) gene expression in rat dorsal root ganglia following peripheral nerve injury

Although an increase in the excitability and ectopic spontaneous discharge (ESD) of primary sensory neurons can lead to abnormal burst activity, which is associated with neuropathic pain, the underlying molecular mechanisms are not fully understood. To investigate the relationship between these electrical abnormalities in injured neurons and voltage-gated calcium channel (VGCC) gene expression, reverse transcription-polymerase chain reaction (RT-PCR) was used to monitor the expression of the VGCC alpha(1) gene in the dorsal root ganglion (DRG) following chronic constriction injury (CCI) and axotomy of the rat sciatic nerve. Electrophoresis of the RT-PCR products showed the presence of multiple types of VGCC alpha(1) transcripts with various levels of basal expression in lumbar 4, 5, and 6 DRGs. CCI decreased alpha(1C), alpha(1D), alpha(1H), and alpha(1I) mRNA expression at 7 days in the ipsilateral DRG, to approximately 34-50% of the contralateral side. The same transcripts were repressed 7 days after sciatic axotomy and their reduction levels proved similar to those of CCI. Considering that changes of the intracellular calcium concentration modify the maintenance of ESD in injured DRG, these results suggest that the downregulation of alpha(1C), alpha(1D), alpha(1H) and alpha(1I) subunit gene expression in the rat DRG following peripheral nerve injury may contribute to the production of ESD associated with damaged nerves.

Differentially expressed genes in rat dorsal root ganglia following peripheral nerve injury

Ordered differential display PCR was used to identify differentially expressed genes in rat dorsal root ganglia at 7 days following chronic constriction injury (CCI) of the sciatic nerve. Fourteen differentially displayed cDNA bands were isolated, cloned and verified by RT-PCR. The four mRNAs were increased, which included mRNAs encoding heat shock protein 27, fatty acid binding protein, apolipoprotein D and one novel gene. Six down-regulated clones were microtubule-associated protein 1B, protein tyrosine phosphatase alpha, Kv1.2 channel, myelin protein SR13, medium-sized neurofilament protein, and one novel gene. Our results show that many differentially regulated genes after CCI may play a role in nerve degeneration and/or regeneration and provide a molecular framework for understanding the peripheral mechanism underlying neuropathic pain.

Expression of vascular endothelial growth factor and inducible nitric oxide synthase in pterygia

PURPOSE

To evaluate the expression of vascular endothelial growth factor (VEGF) in pterygium and investigate the interrelationships between VEGF and nitric oxide (NO) in the development of pterygia.

METHODS

Specimens of normal conjunctiva acquired incidentally to conjunctival transplantation during pterygium and strabismus surgery and the excised pterygium were used in this study. Cryopreserved tissue specimens consisting of normal conjunctiva and pterygium were used to study the expression of VEGF and inducible NO synthetase (iNOS), using immunohistochemistry. For confirmation of NOS activity, reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase staining was done. Enzyme-linked immunosorbent assay (ELISA) for detection and quantification of VEGF was performed.

RESULTS

Expression of VEGF and iNOS was strongly revealed mainly in the epithelium of the head portions of pterygial specimens, although not in the epithelium of conjunctival ones. Pterygial epithelium was stained with NADPH diaphorase, confirming NOS activity. ELISA showed a greater amount of VEGF in pterygium (11.7 +/- 2.1 pg/mg) compared with normal conjunctiva (4 +/- 0.47 pg/mg) ( p < 0.05).

CONCLUSION

These data are the first to demonstrate that VEGF and NO may play an important role in the development of pterygium and to identify VEGF and NO in the epithelium of pterygium. We hypothesize that environmental stress, such as ultraviolet irradiation and local inflammation stimulate the elaboration of NO and VEGF, resulting in the conjunctival fibrovascular ingrowth characteristic of pterygium.

Differential usage of multiple brain-derived neurotrophic factor promoter in rat dorsal root ganglia following peripheral nerve injuries and inflammation

The brain-derived neurotrophic factor (BDNF) may act as either an autocrine or paracrine survival factor for the dorsal root ganglion (DRG) neurons and may also serve as a neurotransmitter or neuromodulator within the dorsal horn of the spinal cord. The rat BDNF gene consists of four short 5' exons linked to separate promoters and one 3' exon encoding the mature BDNF protein. An exon-specific reverse transcription-polymerase chain reaction analysis was used to study the differential utilization of multiple promoters in the DRG following unilateral sciatic axotomy, dorsal rhizotomy and peripheral inflammation. The exon I transcript showed the highest induction rate with the ipsilateral expression elevated 4.3-5.8 times that of contralateral expression. Both exon II and III mRNAs showed a smaller increase 1 day after the three kinds of stimuli. In addition, exon IV mRNA transcription increased slightly only after rhizotomy, but not after axotomy and peripheral inflammation after 1 day. Furthermore, the elevated exon I mRNA levels 1 day after rhizotomy were sustained for up to 7 days. In contrast, those of the exon I mRNA after axotomy had declined 2.8 times the control level after 7 days. These findings suggest that the promoter linked to exon I may provide a major regulatory point of BDNF mRNA expression by peripheral nerve injuries and inflammation. In addition, both exon I and IV mRNA expression may show different temporal activation patterns according to the types of injury.

C5b-9 terminal complement complex protects oligodendrocytes from death by regulating Bad through phosphatidylinositol 3-kinase/Akt pathway

Apoptosis of oligodendrocytes is induced by serum growth factor deprivation. We showed that oligodendrocytes and progenitor cells respond to serum withdrawal by a rapid decline of Bcl-2 mRNA expression and caspase-3-dependent apoptotic death. Sublytic assembly of membrane-inserted terminal complement complexes consisting of C5b, C6, C7, C8, and C9 proteins (C5b-9) inhibits caspase-3 activation and apoptotic death of oligodendrocytes. In this study, we examined an involvement of the mitochondria in oligodendrocyte apoptosis and the role of C5b-9 on this process. Decreased phosphatidylinositol 3-kinase and Akt activities occurred in association with cytochrome c release and caspase-9 activation when cells were placed in defined medium. C5b-9 inhibited the mitochondrial pathway of apoptosis in oligodendrocytes, as shown by decreased cytochrome c release and inhibition of caspase-9 activation. Phosphatidylinositol 3-phosphate kinase and Akt activities were also induced by C5b-9, and the phosphatidylinositol 3-phosphate kinase inhibitor LY294002 reversed the protective effect of C5b-9. Phosphatidylinositol 3-phosphate kinase activity was also responsible for the phosphorylation of Bad at Ser112 and Ser136. This phosphorylation resulted in dissociation of Bad from the Bad/Bcl-xL complex in a G(i)alpha-dependent manner. The mitochondrial pathway of oligodendrocyte apoptosis is, therefore, inhibited by C5b-9 through post-translational regulation of Bad. This mechanism may be involved in the promotion of oligodendrocyte survival in inflammatory demyelinating disorders affecting the CNS.

Dramatically accelerated growth and extraordinary gigantism of transgenic mud loach Misgurnus mizolepis

Transgenic mud loaches (Misgurnus mizolepis), in which the entire transgene originated from the same species, have been generated by microinjecting the mud loach growth hormone (mlGH) gene fused to the mud loach beta-actin promoter. Out of 4,100 eggs injected, 7.5% fish derived from the injected eggs showed dramatically accelerated growth, with a maximum of 35-fold faster growth than their non-transgenic siblings. Many fast-growing transgenic individuals showed extraordinary gigantism: their body weight and total length (largest fish attained to 413 g and 41.5 cm) were larger and longer than even those of 12-year-old normal broodstock (maximum size reached to 89 g and 28 cm). Of 46 transgenic founders tested, 30 individuals transmitted the transgene to next generation with a wide range of germ-line transmission frequencies ranging from 2% to 33%. The growth performance of the subsequent generation (F1) was also dramatically accelerated up to 35-fold, although the levels of enhanced growth were variable among transgenic lines. Three transgenic germ-lines up to F4 were established, showing the expected Mendelian inheritance of the transgene. Expression of GH mRNA in many tissues was detected by RT-PCR analyses. The time required to attain marketable size (10 g) in these transgenic lines was only 30-50 days after fertilization, while at least 6 months in non-transgenic fish. Besides growth enhancement, significantly improved feed-conversion efficiency up to 1.9-fold was also observed.

Real-time full-color three-dimensional display with a micromirror array

We designed, realized, and tested what is believed to be the first real-time, full-color, autostereoscopic three-dimensional (3-D) display with a micromirror array. Compared with the diffractive partial pixel architecture [Opt. Lett. 20, 1418 (1995)], this approach has certain advantages:(1) Micromirrors are reflective and thus achromatic (panchromatic) and (2) a variety of displays can be used as the image source. We used backlit transparencies to test the system and then used an ordinary color CRT to show several computer-generated full-color 3-D animations.

Cost-effective monitoring for a soil vapor extraction (SVE) system: a simplified modeling and gas sensor test

In order to establish cost-effective monitoring strategies for soil vapor extraction (SVE), a simplified model for multi-component mass transfer of a complex liquid mixture in porous media and gas sensor are proposed and experimentally evaluated. The basic task for the cost-effective monitoring of SVE is to decide how to predict the performances of venting systems in terms of the contaminant vapor removal rate and the time required to accomplish the clean-up specification. The method includes classifying of individual components of a complex mixture on the basis of gas chromatographic (GC) profile and treating each resulting group as a pseudo-single compound. BTEX components of gasoline were selected for model input and the remainders were divided into 4 groups based on their GC retention times. The model proposed in this study is capable of predicting with accuracy volatilization behaviors of gasoline components in soil and the gas sensor (FIGARO TGS 823) was tested by GC-FID to toluene and TPH-GRO(Total Petroleum Hydrocarbon-Gasoline Range Organics) gas samples. A VOC gas sensor was developed which recognizes TPH-GRO concentrations between 250 and 50 ppm. The developed gas sensor test and proposed model can be used as a valuable tool for the cost-effective monitoring for SVE systems.

Production of transgenic male sterile tobacco plants with the cDNA encoding a ribosome inactivating protein in Dianthus sinensis L

The ribosome inactivating protein (RIP) gene from D. sinensis was used as a cytotoxin gene to induce male sterility in tobacco plants. The TA29 promoter, obtained by PCR amplification from tobacco, was fused to the RIP cDNA, and the chimaeric molecule was then introduced into tobacco plants by Agrobacterium-mediated transformation. Out of twenty-one independent transformants, twenty transgenic tobacco plants exhibited male sterility. Southern blot analysis revealed that four of the transgenic plants contained a single copy of the RIP gene, while the rest of the transgenic tobacco plants had two to four copies of the gene. The transgenic male sterile plants set seeds normally when pollinated with pollens from untransformed control plants, indicating that the RIP gene does not affect the pistil development. Furthermore, the seed yield of the transgenic plant was similar to that of the untransformed, self-pollinated control plant. A light microscopic observation of anther cross sections clearly showed that the tapetal tissue of the anther was selectively and completely destroyed causing male sterility. This study suggests that the RIP gene can be used as a cytotoxin gene for induction of male sterility in the plant.

Correlation of hematopoietic progenitor cell count determined by the SE-automated hematology analyzer with CD34(+) cell count by flow cytometry in leukapheresis products

The yield of stem cell collection after mobilization is crucial for autologous peripheral blood stem cell (PBSC) transplantation. Quantitative determinations of CD34(+) cells using flow cytometry or stem cell culture have been used, but these methods require much time, technical experience, and expensive reagents. The automated hematology analyzer (Sysmex SE-9000trade mark, TOA, Japan) equipped with the Immature Information (IMI) channel for immature myeloid cells can detect IMI(+) cells within 90 sec. Detection is made possible by the combination of a special reagent system and direct current/radiofrequency biosensors. We studied the relation of IMI(+) cells and variable cell counts with CD34(+) cell yield in autologous stem cell harvest. In a series of 32 patients (median age, 44 years; M:F = 11:21), 184 leukaphereses were performed after mobilization regimens with chemotherapy and G-CSF or G-CSF alone. Full blood cell counts were enumerated on peripheral blood (PB) samples taken prior to each leukapheresis. Mononuclear cell (MNC) and IMI(+) cell counts by automated hematology analyzer and flow cytometry based CD34(+) cell yield were measured on the harvested product. The relationship among PB white blood cells (WBC), PB monocytes, IMI(+) cells, MNC, and CD34(+) cell yield in a single leukapheresis was estimated by Pearson correlation analysis. PB WBC count showed no correlation with CD34(+) cell yield in a single leukapheresis (r = 0.02, P = 0.81). PB monocyte count showed a weak correlation (r = 0.21, P = 0.01) and MNC in harvest also showed a weak correlation (r = 0.36, P = 0.0001) with CD34(+) cell yield. In contrast, CD34(+) cell yield correlated well with IMI(+) cell count (r = 0.68, P = 0.0001), and data could be fitted by a linear regression equation, y = 0.330 + 0.974x. IMI(+) cell assay by the automated hematology analyzer correlated well with the CD34(+) cell yield in a mobilized autologous stem cell harvest. The IMI(+) cell count might be used as a simple and efficient indicator of blood stem cell mobilization and collection.

Growth inhibition and chemosensitivity of poorly differentiated human thyroid cancer cell line (NPA) transfected with p53 gene

BACKGROUND

We investigated whether retroviral p53 transfection could enhance growth inhibition and chemosensitivity in a p53 mutant papillary thyroid cancer cell line (NPA).

METHODS

NPA cells were transfected with either LXSN/p53 or mock infection in the presence of Adriamycin. Gene expression was confirmed by western blotting. Nude mice were injected subcutaneously with NPA cells after transfection with either LXSN/p53 or mock infection on opposite sides, and the tumor growth was compared.

RESULTS

There was a dose-dependent inhibition of tumor growth with LXSN/p53 transfection. Tumor growth was inhibited more by p53 gene transfection relative to mock transfection in the presence of Adriamycin.

CONCLUSION

These treatment modalities could be beneficial in the treatment of p53 mutant positive thyroid cancers.

Effects of brain-derived neurotrophic factor and neurotrophin-3 on expression of mRNAs encoding c-Fos, neuropeptides and glutamic acid decarboxylase in cultured spinal neurons

There is growing evidence suggesting that neurotrophins have modulating effects on the pain signaling system at spinal levels. In order to determine whether neurotransmitter expression is modulated in response to the elevation of neurotrophins, the changes in c-fos, neuropeptide and glutamic acid decarboxylase (GAD) mRNAs expression was evaluated after BDNF or NT-3 was applied to cultured spinal neurons. Reverse transcription polymerase chain reaction analysis revealed that BDNF induced a significant increase in the expression of preprodynorphin (pDYN), preproenkephalin (pENK), neuropeptide Y (NPY) and GAD mRNAs. In contrast, the pENK, not the pDYN, NPY and GAD, mRNA levels increased after the treatment of NT-3. Both BDNF and NT-3 produced a rapid increase in c-fos mRNA. These results suggest that BDNF and NT-3 have differential neuronal effects on the synthesis of spinal cord neurotransmitters that are involved in the modulation of nociceptive information.

Capsaicin effects on brain-derived neurotrophic factor in rat dorsal root ganglia and spinal cord

The effects of capsaicin systemically administered in adult rats, with the major focus on the expression of brain-derived neurotropic factor (BDNF) and its mRNA in the dorsal root ganglion (DRG) and spinal cord, has been investigated by means of immunohistochemistry and reverse transcriptase-polymerase chain reactions. The percentage of BDNF-immunoreactive neurons in the L5 DRG was found to increase significantly 1 day after capsaicin injection. Subsequently, it decreased slowly returning to near normal levels 1 week later. Four weeks post-injection, a significant reduction to below normal levels was observed. The temporal pattern of BDNF mRNA expression in the DRG was similar to BDNF-immunoreactivity. In the spinal cord, 1 and 3 days post-injection, no changes in the expression of the BDNF-immunoreactive axonal fibers was noted. However, the expression had decreased significantly after 1 and 4 weeks. The mechanism by which capsaicin induces changes in expression of BDNF in DRG neurons and the functional significance of the rapid increase in BDNF levels in the DRG is discussed briefly.

Transanally injected triamcinolone acetonide in levator syndrome

PURPOSE

Several treatments are used for the treatment of levator syndrome, such as rectal massage, biofeedback, and galvanic stimulation. But their effects are inconsistent, and multiple treatment sessions are usually required. Triamcinolone acetonide and lidocaine mixture was injected locally into the tenderest point in levator syndrome under the hypothesis that levator syndrome is caused by tendinitis of pelvic floor musculature.

METHODS

A mixture of 40 mg of triamcinolone acetonide and 1 ml of 2 percent lidocaine was injected into the tenderest point transanally in 104 patients (33 males; mean age, 51 years) with levator syndrome from December 1996 to May 1998 at Daehang Clinic. Additional injections were repeated at two-week intervals to a maximum of three injections in cases of poor response. Follow-up was performed prospectively concerning patient's perception of pain level using a visual analog scale. Depending on the response, the patients were classified into four groups: pain-free, good, fair, and no response. More than 50 percent pain reduction was classified as "good," and less than 49 percent reduction as "fair."

RESULTS

The injection regions, where the tenderest points were identified on digital rectal compression, were left anterior anal canal in 71.2 percent of patients, right anterior in 3.8 percent of patients, and posterior in 25 percent of patients. The results of treatment were as follows: at three months after injection, response was classified as pain-free in 36.8 percent of patients, good in 35 percent of patients, fair in 19.5 percent of patients, and no response in 8.7 percent of patients; at six months the response was pain-free in 30.1 percent of patients, good in 46.5 percent of patients, fair in 18.2 percent of patients, and no response in 5.2 percent of patients. Most patients, except 8.7 percent at three months and 5.2 percent at six months, experienced treatment benefits. There were no complications during the follow-up periods.

CONCLUSION

Transanal injection of triamcinolone acetonide and lidocaine mixture into the tenderest point is such a simple, safe, and very effective modality that it can be recommended as a primary therapy for levator syndrome.

Increasing tryptophan synthesis in a forage legume Astragalus sinicus by expressing the tobacco feedback-insensitive anthranilate synthase (ASA2) gene

A cDNA clone that encodes a feedback-insensitive anthranilate synthase (AS), ASA2, isolated from a 5-methyl-tryptophan (Trp) (5MT)-resistant tobacco cell line under the control of the constitutive cauliflower mosaic virus 35S promoter, was introduced into the forage legume Astragalus sinicus by Agrobacterium rhizogenes with kanamycin selection. The 35S-ASA2 gene was expressed constitutively as demonstrated by northern-blot hybridization analyses and the presence of feedback-insensitive AS. Hairy root lines transformed with 35S-ASA2 grew in concentrations of up to 100 microM 5MT, whereas the controls were completely inhibited by 15 microM 5MT. Expression of the feedback-insensitive ASA2 resulted in a 1.3- to 5.5-fold increase in free Trp. Kinetic studies of the AS activity demonstrate the Trp feedback alterations and indicate that the ASA2 alpha-subunit can interact with the native A. sinicus beta-subunit to form an active enzyme. The ASA2 transcript and high free Trp were also detected in the leaves, stems, and roots of plants regenerated from the transformed hairy roots. Thus, we show for the first time that ASA2 can be used to transform plants of a different species to increase the levels of the essential amino acid Trp and impart 5MT resistance.

Immunostimulatory DNA-based vaccines induce cytotoxic lymphocyte activity by a T-helper cell-independent mechanism

Immunostimulatory DNA sequences (ISS) contain unmethylated CpG dinucleotides within a defined motif. Immunization with ISS-based vaccines has been shown to induce high antigen-specific cytotoxic lymphocyte (CTL) activity and a Th1-biased immune response. We have developed a novel ISS-based vaccine composed of ovalbumin (OVA) chemically conjugated to ISS-oligodeoxynucleotide (ODN). Protein-ISS conjugate (PIC) is more potent in priming CTL activity and Th1-biased immunity than other ISS-based vaccines. Cytotoxic lymphocyte activation by ISS-ODN-based vaccines is preserved in both CD4-/- and MHC class II-/- gene-deficient animals. Furthermore, PIC provides protection against a lethal burden of OVA-expressing tumor cells in a CD8+ cell-dependent manner. These results demonstrate that PIC acts through two unique mechanisms: T-helper-independent activation of CTL and facilitation of exogenous antigen presentation on MHC class I. This technology may have clinical applications in cancer therapy and in stimulating host defense in AIDS and chronic immunosuppression.

Isolation and characterization of cDNAs encoding ribosome inactivating protein from Dianthus sinensis L

To isolate a ribosome inactivating protein (RIP) gene, six plant species were surveyed for antiviral activity. Crude proteins extracted from these plants were tested for the antiviral activity against tobacco mosaic virus (TMV) in Nicotiana glutinosa. All the plants, Spinacia oleracea, Amaranthus lividus, Dianthus superbus, Dianthus sinensis and Celosia cristata, with an exception of Oenanthe stolonifera, presented 70-90% inhibition of viral infectivity. In an attempt to search for the RIP gene from D. sinensis, partial cDNA was obtained by polymerase chain reaction (PCR) of the poly(A)+ RNA from D. sinensis leaves. DNA gel blot analysis showed that D. sinensis has multi-copy RIP genes. The expression of RIP gene was investigated in the flower, leaf, root and stem of D. sinensis, and was found to be most abundant in the leaf. Using the partial cDNA as a probe, seven full-length cDNAs were isolated from a library prepared from D. sinensis leaves. They were divided into three groups on the basis of their nucleotide sequence homology. The three representative clones, cDsRIP1, cDsRIP2 and cDsRIP3 were completely sequenced. They all had an open reading frame of 882 bp. The cDsRIP2 showed 79% homology with dianthin 30 and saporin genes; 59% with PAP and Mirabilis antiviral protein MAP genes. From the analysis of deduced amino acid sequences, it was predicted that D. sinensis RIP cDNAs might have a putative signal peptide of 23 amino acid residues at their N-terminus. When the cDNA was expressed in E. coli, the bacteria was unable to grow upon IPTG induction, suggesting that expression of the gene renders toxicity to E. coli cells.

DNA ploidy patterns in gastric adenocarcinoma

To assess the value of DNA ploidy, flow cytometric analysis was performed on unfixed fresh materials obtained from 86 patients with gastric cancer who underwent stomach resection. We evaluated the DNA content of gastric carcinoma cells from four different sites and compared it with Ki-67 proliferating activity, and other pathologic parameters. The incidence of aneuploid and diploid was similar (48.8% vs. 51.1%). Early gastric carcinoma showed a higher rate of the diploid pattern (75%) compared to that of advanced gastric carcinoma (47.3%). DNA diploidy was noted increasingly in diffuse-type tumors according to Lauren, in signet ring cell type tumor according to WHO classification and in poorly differentiated tumors (p<0.05). Well and moderately differentiated carcinomas revealed the aneuploid pattern more frequently than poorly differentiated tumors. The aneuploidy was associated with high S phase fraction and high proliferative index. Aneuploidy was noted in the mucosa adjacent to the tumor (26%), in the close normal-looking mucosa (7%) and in the remote normal-looking mucosa (3%). This result suggest the possible role of field cancerization in the development of gastric adenocarcinoma.

High-efficiency induction of soybean hairy roots and propagation of the soybean cyst nematode

Cotyledon explants of 10 soybean [Glycine max (L.) Merr.] cultivars were inoculated with Agrobacterium rhizogenes strain K599 with and without binary vectors pBI121 or pBINm-gfp5-ER possessing both neomycin phosphotransferase II (nptII) and beta-glucuronidase (gus) or nptII and green fluorescent protein (gfp) genes, respectively. Hairy roots were produced from the wounded surface of 54-95% of the cotyledon explants on MXB selective medium containing 200 microg ml(-1) kanamycin and 500 microg ml(-1) carbenicillin. Putative individual transformed hairy roots were identified by cucumopine analysis and were screened for transgene incorporation using polymerase chain reaction. All of the roots tested were found to be co-transformed with T-DNA from the Ri-plasmid and the transgene from the binary vectors. Southern blot analysis confirmed the presence of the 35S-gfp5 gene in the plant genomes. Transgene expression was also confirmed by histochemical GUS assay and Western blot analysis for the GFP. Attempts to induce shoot formation from the hairy roots failed. Infection of hairy roots of the soybean cyst nematode (Heterodera glycines Ichinohe)-susceptible cultivar, Williams 82, with eggs of H. glycines race 1, resulted in the development of mature cysts about 4-5 weeks after inoculation. Thus the soybean cyst nematode could complete its entire life cycle in transformed soybean hairy-root cultures expressing GFP. This system should be ideal for testing genes that might impart resistance to soybean cyst nematode.

Traditional medicine, professional monopoly and structural interests: a Korean case

Oriental medicine (OM) is a widely practised traditional healing modality across the East Asian countries. The typical operating mode of traditional medicine in the region is characterized by a relatively stable, though asymmetrical, relationship with the biomedically-oriented health care system with a varying degree of collaboration. The present paper looks at the major conflict between OM and pharmacy in South Korea in the 1990s. Most of the discussions over the so-called 'Hanyak Punjaeng'(OM vs pharmacy dispute) have so far been carried out in the perspective of interest/pressure group politics. But this paper presents an alternative analysis about the genesis, process and resolution of the dispute. It is argued that Robert Alford's 'structural interests' model, rather than the conventional pluralist perspective, offers the most plausible explanation of the conflict. Three key findings are ascertained. First, a sectional, inter-professional conflict can erupt into a major social cataclysm beyond the confines of health care services, an unlikely incident of a 'low politics' case becoming a 'high politics' affair. Second, a bipartite professional monopoly based on the principle of professional credentialism came to be established. Third, the dispute brought about a notable change in the structural power distribution between the corporate rationalizer and professional monopolist.

Detection of antibodies to equine arteritis virus by a monoclonal antibody-based blocking ELISA

A potent ELISA antigen was prepared from equine arteritis virus (EAV) by differential centrifugation of EAV-infected cell culture fluid, followed by solubilization of the preparation by Triton X-100 treatment. Using this antigen and a mouse monoclonal antibody against the G(L) protein of EAV, a reliable blocking ELISA (bELISA) was developed for the detection of EAV antibodies in equine sera. The bELISA was evaluated using a total of 837 test serum samples. The relative sensitivity (n = 320) of the bELISA compared to the serum neutralization (SN) test was 99.4%. The bELISA appears to be a highly specific test, the specificity of which did not appear to be adversely affected by previous exposure of horses to non-EAV-containing biologicals. Of 119 serum samples, 21 from horses without any history of exposure to EAV and 98 from racetrack Thoroughbreds, 118 were negative in the SN test and bELISA. One sample was SN-negative but suspicious with the bELISA. Based on testing 465 SN-negative field samples and 52 SN-negative samples from experimental horses, and excluding any sera giving a suspicious reaction, the relative specificity of the bELISA was 97.7%. Samples should be examined undiluted and diluted 1/10 in the bELISA because the testing of sera of high neutralizing antibody titer may be affected by a prozone-like phenomenon. The bELISA is a more rapid and cost-efficient test than the SN test for the detection of EAV antibodies in equine sera.

c-Myc expression is related with cell proliferation and associated with poor clinical outcome in human gastric cancer

We underwent protein assay for Myc expression in 76 human gastric cancer tissues using immunohistochemistry. Expression of Myc protein was analyzed according to proliferative indices measured by flow cytometry. Levels of Myc protein expression was evaluated by correlating with biologic and clinical parameters. In 36 (47.4%) of 76 primary gastric cancers, overexpression of Myc was observed. We could observe expression of Myc protein in a significant portion of early gastric cancer (42.9%). Expression of Myc protein was demonstrated to be more frequent in poorly differentiated cancer cells (p=0.043). However, expression of Myc protein had little influence over progress or extent of the disease. Expression of Myc protein was significantly correlated with increased proliferative activity (p=0.032) and patients with high levels of Myc expression had poor disease-free survival. In a certain proportion of human gastric cancer, Myc protein may function as a regulator of cancer cell growth and expression of Myc may represent an aggressive phenotype of gastric cancer.

Expression of mRNAs encoding full-length and truncated TrkB receptors in rat dorsal root ganglia and spinal cord following peripheral inflammation

Peripheral inflammation induces an increased brain-derived neurotrophic factor (BDNF) synthesis in the dorsal root ganglion (DRG) and an elevated anterograde transport of BDNF to axon terminals in the spinal dorsal horn. To characterize whether expression of trkB is modulated in response to BDNF elevation in these areas, we evaluated changes in expression of full-length and truncated trkB (trkB.FL and trkB.T) mRNAs after injection of complete Freund's adjuvant into the hind paw of the rat. Reverse transcription-polymerase chain reaction analysis revealed that BDNF and trkB.T mRNAs levels in the DRG increased, while no change of expression of trkB.FL mRNA was observed. There was no detectable change in both trkB.FL and trkB.T mRNAs levels in the spinal cord. Considering that trkB.T mRNA is expressed mainly in the perineuronal satellite cells, these results suggest a possible paracrine role of BDNF within the DRG in addition to an important role related with nociception following peripheral inflammation.

Expression of brain-derived neurotrophic factor in catecholaminergic neurons of the rat lower brainstem after colchicine treatment or hemorrhage

Widespread brain-derived neurotrophic factor messenger RNA expression has been detected in the region of catecholamine groups of the rat lower brainstem, while few brain-derived neurotrophic factor-immunoreactive cells were found in this area. In the present study, a double-color immunofluorescence technique for brain-derived neurotrophic factor and tyrosine hydroxylase after colchicine treatment was employed to evaluate the possible presence of brain-derived neurotrophic factor immunoreactivity in the catecholaminergic cells of the rat lower brainstem. We detected many new brain-derived neurotrophic factor-immunoreactive cells in the A1, A2, A4, A6-A10 and C1-C3 cell groups and in the other lower brainstem nuclei where, without colchicine treatment, brain-derived neurotrophic factor messenger RNA was expressed, but not brain-derived neurotrophic factor immunoreactivity. In addition, the catecholaminergic neurons were found to express brain-derived neurotrophic factor immunoreactivity with the co-existence being greatest, in percentage terms, in medullary catecholaminergic cell groups. Hypotensive hemorrhage, which activates medullary catecholaminergic neurons, induced the expression of brain-derived neurotrophic factor immunoreactivity in catecholaminergic neurons (A1/C1 and C2). The results demonstrate that brain-derived neurotrophic factor is regulated by neuronal activity in medullary catecholaminergic cell groups involved in central cardiovascular regulation.

Web based 3-D medical image visualization on the PC

With the recent advance of Web and its associated technologies, information sharing on distribute computing environments has gained a great amount of attention from many researchers in many application areas, such as medicine, engineering, and business. One basic requirement of distributed medical consultation systems is that geographically dispersed, disparate participants are allowed to exchange information readily with each other. Such software also needs to be supported on a broad range of computer platforms to increase the softwares accessibility. In this paper, the development of world-wide-web based medical consultation system for radiology imaging is addressed to provide platform independence and greater accessibility. The system supports sharing of 3-dimensional objects. We use VRML (Virtual Reality Modeling Language), which is the defacto standard in 3-D modeling on the Web. 3-D objects are reconstructed from CT or MRI volume data using a VRML format, which can be viewed and manipulated easily in Web-browsers with a VRML plug-in. A Marching cubes method is used in the transformation of scanned volume data sets to polygonal surfaces of VRML. A decimation algorithm is adopted to reduce the number of meshes in the resulting VRML file. 3-D volume data are often very large in size, hence loading the data on PC level computers requires a significant reduction of the size of the data, while minimizing the loss of the original shape information. This is also important to decrease network delays. A prototype system has been implemented (http://cybernet5.snu.ac.kr/-cyber/mrivrml .html), and several sessions of experiments are carried out.

Intrapulmonary and gastric teratoma : report of two cases

The lung and stomach are very unusual sites for teratoma. The histologic findings of intrapulmonary and gastric teratomas are not different from those arising in usual sites, such as the ovary or testis. However, preoperative diagnosis is sometimes difficult to make partly because of unusual location. We report here two cases of teratoma, one intrapulmonary teratoma and the other gastric. The intrapulmonary teratoma in our study had an endobronchial tumor growth, which rules out mediastinal teratoma. Meanwhile gastric teratomas usually present as a submucosal tumor and most cases are reported in infancy and childhood. Gastric teratoma in this study occurred in a 27-year-old man. To the best of our knowledge, this case of intrapulmonary teratoma is the eighth and the gastric teratoma is the first to be reported in Korea.

Drug-resistant pulmonary tuberculosis in a tertiary referral hospital in Korea

OBJECTIVES

To estimate the resistance rate and to correlate the clinical characteristics of resistant tuberculosis with the patients of pulmonary tuberculosis who were referred to the university hospital.

METHODS

We prospectively performed sensitivity tests for all patients who were diagnosed as active tuberculosis by sputum smear or sputum culture from January, 1995 to June, 1996. Patients profile, previous treatment history, patterns of drug resistance, initial chest films and other clinical findings were analysed.

RESULTS

Overall, 24(26.0%) of the 92 patients had resistance to at least one drug and 8(8.6%) had resistance to isoniazid(INH) and rifampin(RFP). Among the 66 patients without previous tuberculosis therapy, 11(16.6%) were drug-resistant and 2(3.0%) were multi-drug resistant. Among the 26 patients with previous therapy, 13(50.0%) were drug-resistant and 6(23.0%) were multi-drug resistant. For all 92, resistance to INH was most common (19.5%), followed by RFP (9.7%) and ethambutol (9.7%). Drug resistance was significantly high in previously treated patients and in cavity-positive patients. Treatment failure was also high in previously treated patients with resistant tuberculosis. In patients with primary resistance, treatment failure was not observed.

CONCLUSION

Sensitivity tests are strongly recommended in all culture positive patients with previous therapy but, in patients with primary resistance, sensitivity tests are not required. Proper combination chemotherapy should be given under careful surveillance.

Immunostimulatory DNA is a potent mucosal adjuvant

Most proteins delivered to mucosal surfaces fail to induce mucosal or systemic immune responses. We demonstrate that a single intranasal (i.n.) coadministration of a model antigen (beta-galactosidase, beta-gal) with immunostimulatory sequence oligodeoxynucleotide (ISS-ODN) induces a mucosal IgA response equivalent to that induced by i.n. codelivery of beta-gal with cholera toxin (CT). Furthermore, i.n. and intradermal (i.d.) delivery of the beta-gal/ISS-ODN mix stimulates equivalent Th1-biased systemic immune responses with high-level cytotoxic T lymphocyte (CTL) activity. In contrast, i.n. immunization with beta-gal and CT results in a Th2-biased systemic immune response with poor CTL activity. Our data show that i.n. delivery of ISS-ODN provides effective adjuvant activity for the induction of both mucosal and systemic Th1-biased immune responses. This immunization approach deserves consideration in the development of vaccines against mucosal pathogens.

Changes in brain-derived neurotrophic factor immunoreactivity in rat dorsal root ganglia, spinal cord, and gracile nuclei following cut or crush injuries

In the present study, we evaluated changes in brain-derived neurotrophic factor (BDNF) immunoreactivity in the rat lumbar (L) 5 dorsal root ganglion (DRG) and areas where afferents from the DRG terminate, the L5 spinal cord and gracile nuclei, following unilateral sciatic nerve transection or crush. From 3 days to 4 weeks following cut or crush injury, the percentage of medium and large BDNF-immunoreactive neurons in the ipsilateral DRG increased significantly compared with those on the contralateral side. Following cut injury, there was no significant change in the percentage of small BDNF-immunoreactive neurons in the ipsilateral DRG; however, the intensity of immunoreactivity of these cells decreased. Following crush injury, however, both the percentage and intensity of small BDNF-immunoreactive neurons in the ipsilateral DRG significantly increased. Following cut injury, the expression of BDNF-immunoreactive axonal fibers decreased markedly in the ipsilateral superficial laminae of the L5 spinal cord and increased significantly in the ipsilateral deeper laminae of the spinal cord and gracile nuclei. Crush injury induced a marked increase in the expression of BDNF-immunoreactive axonal fibers in the superficial laminae of the spinal cord and gracile nuclei. These differences in BDNF response in the DRG and spinal cord after cut or crush injuries may reflect differences in trophic support to the injured DRG neurons and altered neuronal activity in the spinal cord and gracile nuclei following different types of peripheral nerve injury.

Complement-fixing abilities and IgG subclasses of autoantibodies in epidermolysis bullosa acquisita

Epidermolysis bullosa acquisita (EBA) is an autoimmune-mediated subepidermal bullous disease in which the target of the autoantibodies is type VII collagen, a major component of anchoring fibrils. The purpose of this study was to evaluate the complement-fixing abilities and IgG subclass distribution of autoantibodies in EBA, and to also attempt to investigate the relation between inflammation, complement fixation and IgG subclass distribution in EBA patients. Only 2 sera of 18 patients (11%) showed weak complement-fixing abilities. IgG1 and IgG4 were the most frequently and intensely stained IgG subclasses in EBA sera. We could not find any relationship between the clinico-pathologic types, complement-fixing abilities and IgG subclasses in EBA. These results suggested that complement activation may not be a key factor of bulla formation in EBA.

Performance of ELISA antigens prepared from 8 isolates of porcine reproductive and respiratory syndrome virus with homologous and heterologous antisera

Porcine reproductive and respiratory syndrome virus (PRRSV) ELISA antigens of high quality were produced using 8 different isolates of PRRSV: the European Lelystad virus (LV), the U.S. MN-1b, 89-46448, 93-44927, and 93-24025B, and the Canadian LHVA-93-3, PA-8 and GH-6 virus isolates. The performance of each of these 8 antigens and a commercial PRRSV antibody test kit (Idexx's HerdChek) were measured against antisera raised in 5 groups of 6 piglets inoculated with either LV, MN-1b, 89-46448, 93-44927, or 93-24025B. Among the 8 isolates, the 89-46448 isolate produced the broadest spectrum of antigen and resulted in earlier detection of antibodies to various North American PRRSV isolates, followed by MN-1b as the 2nd best ELISA antigen for the detection of North American PRRSV antibodies. The GH-6 and PA-8 viral antigens exhibited restricted detection of PRRSV antibodies. The LV and 89-46448 combined antigens produced the best performance for the detection of antibodies against both European and North American antigenic types of PRRSV. Using 173 panel samples collected at 11 to 60 d after intranasal inoculation with 1 of the 5 PRRSV isolates, the sensitivities of the indirect ELISA used were 73.4%, 98.3%, 90.8%, 98.3%, 83.2%, 93.1%, 77.1%, 64.2%, 98.8% and 95.9% for LV, MN-1b, LHVA-93-3, 89-46448, 93-44927, 93-24025B, PA-8, GH-6 antigens, 89-46448-LV combined antigens and Idexx's PRRSV antibody test kit, respectively. All 8 antigens gave negative results with preinfection porcine sera (n = 30); high background or nonspecific reactions were not observed with the antigens.

Changes in the alpha 2-adrenergic receptor subtypes gene expression in rat dorsal root ganglion in an experimental model of neuropathic pain

We examined changes in expression of genes coding for alpha 2-AR subtypes in the dorsal root ganglion (DRG) in a rat model (spinal nerve ligation) or neuropathic pain. The present study demonstrates that the majority of DRG neurons express alpha 2C-AR mRNA and a small proportion of neurons express alpha 2A-AR mRNA, while few neurons express alpha 2B-AR mRNA in non-operated animals. In addition, alpha 2C- and alpha 2A mRNA levels in the DRG showed a significant decrease and increase, respectively in ligated animals. These findings suggest that alpha 2A- and alpha 2C-ARs in the DRG may play an important role in generating sympathetically maintained neuropathic pain.

Increased brain-derived neurotrophic factor immunoreactivity in rat dorsal root ganglia and spinal cord following peripheral inflammation

Our recent study showed that peripheral inflammation induced an increased expression of brain-derived neurotrophic factor (BDNF) mRNA which was mediated by nerve growth factor (NGF) in the dorsal root ganglion (DRG). In the present study, we evaluated the change of BDNF immunoreactivity in the DRG and spinal cord following peripheral inflammation by means of immunohistochemistry. Significant increases in the percentage of BDNF-immunoreactive (IR) neuron profiles in the L5 DRG and marked elevation in the expression of BDNF-IR terminals in the spinal dorsal horn were observed following peripheral tissue inflammation produced by an intraplantar injection of Freund's adjuvant into the rat paws. These findings suggest that peripheral tissue inflammation induces an increased BDNF synthesis in the DRG and an elevated anterograde transport of BDNF to the spinal dorsal horn. The functional role of this increased BDNF was discussed briefly.

Comparative study of serological methods for the detection of antibodies to porcine reproductive and respiratory syndrome virus

A comparison was made of serological diagnostic methods used for the detection of antibodies against porcine reproductive and respiratory syndrome (PRRS) virus. In the "phase I" PRRS test panel comparison, a panel of sera collected from 135 pigs of various ages, from North American herds with and without PRRS histories, were sent to 4 different laboratories and tested by an indirect immunofluorescent assay (IFA), an immunoperoxidase monolayer assay (IPMA) and an indirect enzyme-linked immunosorbent assay (iELISA). In the "phase II" PRRS test panel comparison, a panel of 382 sera collected from pigs of various ages, PRRS histories, and from various locations in North America and France, were divided into 2 panels (A & B) and sent to 3 Canadian laboratories and tested by the IFA and iELISA. In the phase I comparison, agreement between the IFA of laboratory 4 and the iELISA and IPMA of laboratory 3 was excellent (kappa values of 95% and 98%, respectively). This contrasted with the poor agreement between these laboratories and the IFA results of laboratories 1 and 2 in the phase I trial. In the phase II comparison, the results demonstrated good agreement between various tests both within and between laboratories. The overall performance of the iELISA was superior in the combination of sensitivity (96.1%) and specificity (100%) relative to the reference classification of the serum samples and repeatability (kappa value 98%). The iELISA is technically superior to IFA and IPMA, time efficient, cost effective and suitable for testing of a large number of samples over a short period of time. Thus, the iELISA may be a better alternative to IFA or IPMA for routine detection of PRRS viral antibodies in swine sera.

Expression of mRNA for brain-derived neurotrophic factor in the dorsal root ganglion following peripheral inflammation

It is well known that the nerve growth factor (NGF) may serve as a link between inflammation and hyperalgesia. Recent experiments showed that systemic injection of NGF dramatically stimulated the expression of brain-derived neurotrophic factor (BDNF) mRNA in the dorsal root ganglion (DRG). In the present study, we evaluated the change of BDNF mRNA in the DRG following peripheral inflammation and also observed colocalization of BDNF and trkA mRNAs by means of in situ hybridization histochemistry in rats. Peripheral tissue inflammation produced by an intraplantar injection of Freund's adjuvant into the paws significantly increased BDNF mRNA levels in the DRG and many neurons expressing trkA mRNA showed increased expession of BDNF mRNA. Intraplantar injection of antibody to NGF together with Freund's adjuvant prevented the increase in BDNF mRNA. These findings suggest that peripheral inflammation induces an increased expression of BDNF mRNA which is mediated by NGF in DRG.