Structural Modifications and Programmed Cell Death of Chili Pepper Fruit Related to Resistance Responses to Colletotrichum gloeosporioides Infection

ABSTRACT Postharvest (detached) and in planta (attached) fruits of pepper plants, Capsicum annuum cv. Jejujaerae (susceptible) and Capsicum baccatum cv. PBC80 (resistant), inoculated with the anthracnose pathogen Colletotrichum gloeosporioides were examined using light, confocal laser scanning, and electron microscopy to compare the cytological differences between the compatible and incompatible interactions. In nonwound inoculation of postharvest pepper fruit, resistant pepper tissues showed a significant increase in the thickness of the cuticle layer compared with that of the susceptible and noninoculated fruit. Cytological features of programmed cell death (PCD) were observed in the resistant pepper fruit with postharvest inoculation, and these were characterized by positive responses to terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. The oligonucleosomal fragments of DNA were confirmed electrophoretically as DNA laddering. The PCD-positive responses occurred around the inoculation sites early in in planta wound inoculation in the resistant pepper. Nuclear modifications and structural changes of hypersensitivity were also observed in the resistant fruit, including separation of the plasma membrane from the cell wall, dilation of the endoplasmic reticulum, accumulation of electron-dense inclusions in vacuoles, and cytoplasmic vacuolization accompanying fragmentation of the cytoplasm. These structural changes may also implicate PCD-like host responses. In addition, in planta wound inoculation resulted in cell enlargement and cell division during the later stages of infection to form a periderm-like boundary layer around the inoculation site.     

Acupoint stimulation using bee venom attenuates formalin-induced pain behavior and spinal cord fos expression in rats

In two previous reports, we have demonstrated that injection of bee venom (BV) into an acupoint produces a significant antinociceptive and anti-inflammatory effect in both a mouse model of visceral nociception and a rat model of chronic arthritis. The present study was designed to evaluate the potential antinociceptive effect of BV pretreatment on formalin-induced pain behavior and it associated spinal cord Fos expression in rats. Adult Sprague-Dawley rats were injected with BV directly into the Zusanli (ST36) acupoint or into an arbitrary non-acupoint located on the back. BV pretreatment into the Zusanli acupoint significantly decreased paw-licking time in the late phase of the formalin test. In contrast, BV injected into a non-acupoint in the back region did not suppress the paw-licking time. In addition, BV pretreatment into the Zusanli acupoint markedly inhibited spinal cord Fos expression induced by formalin injection. These findings indicate that BV pretreatment into the Zusanli acupoint has an antinociceptive effect on formalin-induced pain behavior.     

Application of transarterial embolization of renal artery in rabbits with experimental hydronephrosis

This study was performed to validate the procedure of transarterial embolization of the renal artery (TAE-RA) using iohexol-ethanol solution in rabbits with unilateral experimental hydronephrosis and to evaluate the embolized kidney and contralateral normal kidney using B-mode ultrasonography and color Doppler ultrasonography. Experimental hydronephrosis was induced at 17 days after ligation of unilateral ureter in 13 rabbits. Renal artery embolization was performed using selective catheterization in the hydronephrotic kidney of eight rabbits and electrocardiography, oxygen saturation, body temperature, pulse, and respiratory rate were within normal ranges during procedures. Iohexol-ethanol solution was used as embolic material. Average ethanol dose for renal artery embolization was 1.4 +/- 0.7 ml/kg. There were no rabbits expired after TAE-RA and no side effects associated with regurgitation of iohexol-ethanol solution. In color Doppler ultrasonographic findings, there was no blood flow into the embolized kidneys treated by TAE-RA, however, blood flow signal was found in hydronephrotic kidney not treated by TAE-RA. Ultrasonographically, the mean longitudinal length of the embolized kidney significantly decreased at 2 and 3 months after TAE-RA. No significant difference of resistive index values was found between contralateral normal kidney of rabbits treated by TAE-RA and contralateral normal kidneys of rabbits treated with nephrectomy. We may conclude that TAE-RA with iohexol-ethanol solution is a viable alternative to nephrectomy in rabbits with unilateral hydronephrosis.     

Juvenile malignant mesothelioma in a dog

An 11-month-old male mixed breed dog was euthanized due to two months history of vomiting and anorexia. At necropsy, numerous, multifocal or coalescing, firm, protruding nodules, 5 to 40 mm in diameter were scattered throughout the mesentery and omentum. Histologically and immunohistochemically, the nodules were diagnosed as malignant mesothelioma. Metastasis to the regional mesenteric, mediastinal and tracheobronchial lymph nodes were observed.     

Application of FT-IR and ESR spectroscopic techniques to the study of CCl4-induced peroxidation in rat liver microsomes

FT-Ir and ESR were used for on the investigation of the CCl4-induced peroxidation of rat liver microsomes in combination with biochemical methods. Lipid peroxidation was assayed by TBA reagent in the presence of CCl4 and NADPH. The CCl3. radical was detected by ESR spectroscopy with a spin trapping reagent of PBN. The FT-IR spectroscopy revealed that absorption band of -C-H in -C=C-H decreased in intensity at 3012 cm-1, but the absorption bands of the phosphate head and choline in the phospholipids did not significantly change between 1300 and 900 cm-1. These findings were interpreted to be due to the removal of H. from -C=C-H by radicals as the first step of lipid peroxidation, and to the absence of dephosphorylation of phospholipids in the microsomal membrane. This is the first IR spectroscopic evidence indicating the nature of damage to a microsomal membrane caused by CCl4 treatment. The spectroscopies used here demonstrated that they are useful tools to observe the damage to microsomal membranes.     

Epidemic patterns of encephalitis, hemorrhagic fever and rabies in Korea (1979–1988)

In 1983, 1197 human cases (3.04/10 000 population) of epidemic encephalitis were reported, but practically no further cases of this condition have been reported since 1984. Human cases of encephalitis occurred primarily among those younger than 19 years in rice-field regions in the autumn. The mean number of patients registered annually with hemorrhagic fever from 1979 to 1988 was 46.5 (0.19/10 000 population), being highest in 1979 (73 cases, 0.19/10 000) and lowest in 1982 (32 cases, 0.08/10 000). Hemorrhagic fever occurred among adults mainly in autumn in mountain regions. Two cases of rabies in human and dog were reported in 1984.     

Virus Spread Pattern within Infected Chicken Farms using Regression Model: the 2003–2004 HPAI Epidemic in the Republic of Korea

During the 2003–2004 epidemic in Korea, the infection time and within‐farm spread pattern of virus were analysed for the highly pathogenic avian influenza (HPAI) outbreak on chicken farms using regression models based on epidemiological data. Mortality observed on a given day had a positive linear association with time after initial infection. HPAI spread more rapidly on farms managed by employees and on farms with larger numbers of chicken houses in use. The disease spread more rapidly among layer chickens than among broilers. Using statistical model, we found that farmers recognize the abnormally high mortality resulting from HPAI approximately 5 days after infection. Without any intervention, entire flocks would die within 12 days of introduction of the HPAI virus to the infected farm.     

Diversity in ploidy levels and nuclear DNA amounts in Korean Miscanthus species

Because of its high biomass productivity and nutrient-use efficiency, Miscanthus spp. have emerged as promising bioenergy crops. Polyploidism in Miscanthus species is important because it allows non-native countries to cultivate sterile types, such as triploid M. × giganteus, in order to prevent ecosystem disturbance. Although M. sacchariflorus and M. sinensis are considered to be native to Korea, China, and Japan, accurate information describing the ploidy levels of these species has not yet been well established. To evaluate rough ploidy levels, 215 accessions of Miscanthus species were estimated by relative fluorescence intensities of DAPI-stained nuclei. After evaluation of rough ploidy levels, 20 plants were randomly selected by species and ploidy levels, and ploidy levels were examined by counting chromosomes, estimating propidium iodide-stained DNA content with flow cytometry, and measuring sizes of stomata and caryopsis. Among the 20 plants examined, 3 were diploid and 6 were tetraploid M. sacchariflorus (4.56 ± 0.01 and 8.90 ± 0.14 pg/2C nuclear DNA content, respectively), while 6 were diploid and 3 were triploid M. sinensis (5.40 ± 0.18 and 8.29 ± 0.33 pg/2C nuclear DNA content, respectively). One plant was a putative triploid M. × giganteus having 7.31 pg/2C nuclear DNA content, which was similar to an M. × giganteus plant from Illinois, USA having 7.23 pg/2C nuclear DNA content. We confirmed the occurrence of diploid and tetraploid M. sacchariflorus and M. sinensis plants as well as a putative triploid M. × giganteus native to Korea. Thus, measurement of the size of stomata and caryopsis allowed prediction of ploidy levels in the field and laboratory.     

Friction anisotropy-driven domain imaging on exfoliated monolayer graphene

Graphene produced by exfoliation has not been able to provide an ideal graphene with performance comparable to that predicted by theory, and structural and/or electronic defects have been proposed as one cause of reduced performance. We report the observation of domains on exfoliated monolayer graphene that differ by their friction characteristics, as measured by friction force microscopy. Angle-dependent scanning revealed friction anisotropy with a periodicity of 180° on each friction domain. The friction anisotropy decreased as the applied load increased. We propose that the domains arise from ripple distortions that give rise to anisotropic friction in each domain as a result of the anisotropic puckering of the graphene.