Elucidation of the mode of interaction in the UP1-telomerase RNA-telomeric DNA ternary complex which serves to recruit telomerase to telomeric DNA and to enhance the telomerase activity

We found that UP1, a proteolytic product of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1), both enhances and represses the telomerase activity. The formation of the UP1–telomerase RNA–telomeric DNA ternary complex was revealed by a gel retardation experiment. The interactions in the ternary and binary complexes were elucidated by NMR. UP1 has two nucleic acid-binding domains, BD1 and BD2. In the UP1–telomerase RNA binary complex, both BD1 and BD2 interact with telomerase RNA. Interestingly, when telomeric DNA was added to the binary complex, telomeric DNA bound to BD1 in place of telomerase RNA. Thus, BD1 basically binds to telomeric DNA, while BD2 mainly binds to telomerase RNA, which resulted in the formation of the ternary complex. Here, UP1 bridges telomerase and telomeric DNA. It is supposed that UP1/hnRNP A1 serves to recruit telomerase to telomeric DNA through the formation of the ternary complex. A model has been proposed for how hnRNP A1/UP1 contributes to enhancement of the telomerase activity through recruitment and unfolding of the quadruplex of telomeric DNA.

Species-specific differences in coumarin-induced hepatotoxicity as an example toxicogenomics-based approach to assessing risk of toxicity to humans

One expected result from toxicogenomics technology is to overcome the barrier because of species-specific differences in prediction of clinical toxicity using animals. The present study serves as a model case to test if the well-known species-specific difference in the toxicity of coumarin could be elucidated using comprehensive gene expression data from rat in-vivo, rat in-vitro, and human in-vitro systems. Coumarin 150 mg/kg produced obvious pathological changes in the liver of rats after repeated administration for 7 days or more. Moreover, 24 h after a single dose, we observed minor and transient morphological changes, suggesting that some early events leading to hepatic injury occur soon after coumarin is administered to rats. Comprehensive gene expression changes were analyzed using an Affymetrix GeneChip approach, and differentially expressed probe sets were statistically extracted. The changes in expression of the selected probe sets were further examined in primary cultured rat hepatocytes exposed to coumarin, and differentially expressed probe sets common to the in-vivo and in-vitro datasets were selected for further study. These contained many genes related to glutathione metabolism and the oxidative stress response. To incorporate human data, human hepatocyte cultured cells were exposed to coumarin and changes in expression of the bridging gene set were examined. In total, we identified 14 up-regulated and 11 down-regulated probe sets representing rat-human bridging genes. The overall responsiveness of these genes to coumarin was much higher in rats than humans, consistent with the reported species difference in coumarin toxicity. Next, we examined changes in expression of the rat-human bridging genes in cultured rat and human hepatocytes treated with another hepatotoxicant, diclofenac sodium, for which hepatotoxicity does not differ between the species. Both rat and human hepatocytes responded to the marker genes to the same extent when the same concentrations of diclofenac sodium were exposed. We conclude that toxicogenomics-based approaches show promise for overcoming species-specific differences that create a bottleneck in analysis of the toxicity of potential therapeutic treatments.

The relationship between oxidative stress and acid stress in adult patients with mild asthma

BACKGROUND

Oxidative stress plays an important role in the pathogenesis of asthma. Interestingly, a low airway pH and a high concentration of 8-isoprostane, a marker of oxidative stress, has been reported to cause inflammatory airway diseases. However, the relationship between these 2 markers and pulmonary function has not been determined in mild asthma patients.

METHODS

pH and 8-isoprostane concentration were measured in exhaled breath condensate (EBC) from patients with mild asthma (n = 44) and healthy subjects (n = 20). The relationship between acid stress (pH) and oxidative stress (8-isoprostane) was then analyzed, along with the relationships between these 2 markers and lung function.

RESULTS

The median (interquartile range [IQR]) pH of EBC was significantly lower in asthma patients than in control subjects (7.53 [7.41-7.68] vs 7.70 [7.62-7.74], P < .05), while the median (IQR) 8-isoprostane concentration of EBC was significantly higher in asthma patients than control subjects (16.2 [11.7-19.1] vs 3.5 [2.6-7.9] pg/mL, P < .05). There was no correlation between pH and 8-isoprostane concentration. Furthermore, lung function was not correlated with either pH or 8-isoprostane concentrations in EBC.

CONCLUSIONS

Acid stress and oxidative stress assessed by pH and 8-isoprostane concentration, respectively, in EBC did not show parallel changes associated with asthma and were not correlated with lung function in asthma patients. These 2 stress factors may have different roles in the pathogenesis of asthma.

Acute impact of volcanic ash on asthma symptoms and treatment

Information about the impacts of disasters on health is useful for establishing hazard prediction maps and action plans of disaster management. This study aims at learning effective asthma management from the volcano disaster of Mount Asama eruption in Japan on September 1, 2004. We conducted a cross-sectional study to assess the acute impact of volcanic ash on asthma symptoms and their treatment changes by using a questionnaire completed by 236 adult asthmatic patients and their physicians. In the ashfall over 100g/m2 area, 42.9 percent of asthma patients suffered exacerbations, PEF decreased, asthma treatments increased, and inhalation of beta2 stimulants was used most for exacerbated asthma. Compared to severe asthma patients, mild and moderate asthma patients were most at risk. Severe asthma patients were not affected since most of them knew their asthma status was severe, and did not go outside and kept windows closed. Deteriorated asthma symptoms of wheezing, chest tightness and cough appeared in the ashfall over 100g/m2 area. Ash contained inhalable 10microm diameter particles, and included high concentrations of airway toxic substrates of silica. These data suggest that ashfall over 100 g/m2 is harmful, access to these areas by asthma patients needs to be restricted, and these areas need to improve asthma treatment. In addition, the increase in the proportion of asthma patients with wheeze and cough are diagnostic clues for ash-induced asthma in affected areas, and can be used by doctors to tell whether patients are receiving sufficient asthma treatment.

Pulmonary Computed Tomography Findings of Visceral Larva Migrans Caused by Ascaris suum

OBJECTIVE

To retrospectively evaluate the computed tomography (CT) findings of pulmonary involvement in patients with visceral larva migrans caused by Ascaris suum.

METHODS

Institutional review board approval was obtained, and informed consent was waived. Chest CT scans obtained between January 1994 and November 2005 in 32 patients infected with A. suum were retrospectively evaluated by 3 chest radiologists. In 4 patients who underwent surgical or transbronchial biopsy, comparisons of the CT images with the actual specimens were performed.

RESULTS

On CT scans, abnormal findings were seen in 28 patients. The most common abnormality consisted of nodules (n = 19) in which the majority had a halo of ground-glass attenuation (n = 17), followed by ground-glass attenuation (n = 18), and interlobular septal thickening (n = 14). These abnormalities were predominantly seen in the peripheral lung (n = 25). Of the 7 patients who underwent follow-up CT scans, nodules (n = 6) and ground-glass attenuation (n = 5) had migrated in 4 patients. Pathologically, these findings corresponded to marked eosinophilic infiltration into the interstitium.

CONCLUSIONS

These CT findings are considered to be suggestive of thoracic involvement in patients with visceral larva migrans caused by A. suum.

Acute renal infarction in a patient with left atrial myxoma

A 24-year-old male first attended our hospital with acute onset of right flank pain radiating to the right lower quadrant of the abdomen. A contrast-enhanced computer tomography (CT) scan showed renal infarction, and he was admitted immediately for treatment. On admission, the right lower abdominal pain diminished gradually. On the second day in hospital, a left atrial echogenic mass was detected which filled the left atrial cavity; it appeared to be a left atrial myxoma measuring 3.9+/-4.9 cm. The patient was immediately transferred and underwent emergency surgery. Histologic examination confirmed the diagnosis of myxoma. Post-operatively, he recovered well and was discharged from hospital without any further specific treatment.

Overexpression of p16 INK4a as an indicator for human papillomavirus oncogenic activity in cervical squamous neoplasia

Overexpression of p16(INK4a) has been observed when retinoblastoma protein is inactivated by high-risk human papillomavirus (HPV) oncoprotein E7. We investigated overexpression of p16(INK4a) and HPV infection in cervical squamous neoplasia to evaluate the oncogenic potential among various HPV subtypes. The high-risk HPV was detected by PCR in 69.8% (37/53), 97.5% (39/40), 91.7% (44/48), and 100% (16/16) of cervical intraepithelial neoplasia (CIN)1, CIN2, CIN3, and squamous cell carcinoma (SCC), respectively. The p16(INK4a) overexpression was investigated immunohistochemically using a p16(INK4a)-specific monoclonal antibody (clone E6H4). In high-risk HPV positive cases, 32.4% (12/37) of CIN1, 82.1% (32/39) of CIN2, 93.2% (41/44) of CIN3, and all (16/16) SCC showed p16(INK4a) overexpression. The incidence of p16(INK4a) overexpression was significantly different between CIN1 and CIN2, suggesting that the disorder of cell cycle regulation by HPV frequently occurred from CIN2. As for CIN1 cases, p16(INK4a) overexpression was observed more frequently in HPV16 and HPV52 than in HPV51 and HPV35. Using p16(INK4a) as a bio marker of HPV oncogenic activity, we demonstrate that the level of pRb dysfunction by high-risk HPV varied from subtypes and was getting more frequent from CIN2.

Synthesis of oligodeoxyribonucleotides containing 2'-deoxypseudouridine: inhibition of uracil-DNA glycosylase

2'-Deoxypseudouridine (1) was synthesized starting from thymidine in a 23% overall yield via a silylated furanoid glycal. Compound 1 was introduced to oligodeoxyribonucleotides (ODNs) by the solid phase phosphoramidite chemistry. The ODNs containing 1 inhibited uracil-DNA glycosylase (UDG) reaction.

Synthesis of 5-substituted [N3-15N]-pyrimidine nucleosides: Developing model systems for NMR studies of substituent effects on the N-H...N hydrogen bond in duplex DNA

The effects on various NMR parameters of substitutions, which may influence the hydrogen bond strengths of Watson-Crick-type base pairs, were investigated for DNA dodecamers containing 5-substituted-2'-deoxyuridine derivatives in oligomers, 5'-d(CGCGAATXCGCG)-3', where A and X were [ul-15N]-2'-deoxyadenosine and [3(-15)N]-2'-deoxyuridine derivatives. The substitution effects on the NMR parameters were linearly correlated with the pKa values of the 2'-deoxyuridine derivatives.

Synthesis and characterization of oligodeoxyribonucleotides carrying arrays of intercalating groups

A novel strategy for attaching the functional groups to oligodeoxyribonucleotides (ODNs) is described. A thymidine carrying anthraquinone derivative at the N3 position (AnT) was synthesized and introduced into ODNs using the phosphoramidite method on a DNA synthesizer. Py-Pu-Py type triplex formation of ODNs was enhanced by attaching AnT to the 5'-end of the third strand.

Binding activity of replication protein A to single-stranded DNA containing oxidized pyrimidine base

To obtain the information for the role of replication protein A (RPA) on the detection of oxidized lesion in the single-stranded DNA, the binding preference of RPA purified from Xenopus egg lysate against the oligonucleotide containing one of three kinds of oxidized thymine residues, 5-formyluracil, 5-hydroxymethyluracil and 5-(1,2-dihydroxyethyl)uracil, was studied by the gel shift assay. Results of competition assay indicate that RPA preferentially binds to the oligonucleotide containing these oxidized thymine residues than the undamaged DNA.

Potential remedy against Echinococcus multilocularis in wild red foxes using baits with anthelmintic distributed around fox breeding dens in Hokkaido, Japan

The effect of bait-delivered anthelmintic to reduce the prevalence of Echinococcus multilocularis in wild red foxes was evaluated in Koshimizu, in the eastern part of Hokkaido, Japan. The study area (200 km2) was divided into baited and non-baited sections. The anthelmintic baits were distributed around fox den sites in the baited section every month for 13 months. After 1 year of the anthelmintic bait distribution, the prevalence of E. multilocularis in foxes, evaluated either by the parasite egg examination (from 27.1 to 5.6%) or coproantigen ELISA (from 59.6 to 29.7%), decreased in the baited section contrasting to that in the non-baited section (parasite egg: from 18.8 to 24.2%; ELISA: from 41.9 to 45.8%). The prevalence of E. multilocularis in grey red-backed vole Clethrionomys rufocanus, caught around fox dens, born after bait distribution also decreased and was significantly lower than that in non-baited section. However, within the study periods, the coproantigen-positive rate in fox faeces sporadically increased, while egg-positive rate constantly decreased. Since coproantigen ELISA can detect pre-patent infection, this observation indicates that reinfection pressure in the baited section was still high even after the 13 months of anthelmintic bait distribution. Therefore, the bait distribution longer than our study period is required for the efficient control of E. multilocularis in wild red fox population.

Biosynthetic pathway for production of a conjugated dienyl sex pheromone of a Plusiinae moth, Thysanoplusia intermixta

Virgin females of Thysanoplusia intermixta (Lepidoptera; Noctuidae; Plusiinae) produce (5E,7Z)-5,7-dodecadienyl acetate as a main sex pheromone component. GC-MS analysis of the pheromone glands, which were treated with deuterated hexadecanoic, (Z)-11-hexadecenoic, and (Z)-7-dodecenoic acids, showed incorporation of the label into the dienyl component. Their incorporation rates confirmed that its biosynthesis proceeds in the following order: Delta11-desaturation of a C(16) acyl intermediate, chain shortening to a C(12) compound by beta-oxidation, Delta5-desaturation to produce a 5,7-dienyl system, reduction of the acyl group, and acetylation. These deuterated precursors also converted into a minor pheromone component, (Z)-7-docecenyl acetate, which might be prepared by the same pathway except for the step of Delta5-desaturation. While deuterium incorporation into the dienyl acetate was not observed in the extracts treated with other labeled dodecenoic acids with (E)-5-, (Z)-6-, and (E)-7-double bonds, the corresponding dodecenyl acetates were produced. This result showed low substrate specificity of the enzymes for reduction and acetylation. Labeled (Z)-10-hexadecenoic acid was not converted into a dodecenyl acetate, indicating the high substrate specificity of the enzyme for beta-oxidation.

Solid-phase synthesis of selectively labeled DNA: applications for multidimensional nuclear magnetic resonance spectroscopy

The solid-phase chemical synthesis method has a strong advantage over the enzymatic method for preparing selectively labeled DNA oligomers. Atom-specific and fully labeled 2'-deoxynucleosides are economically prepared with routinely available isotope precursors using this synthetic route. Special DNA oligomers prepared by advanced labeling techniques are needed for advanced NMR applications, and chemical synthesis is the method of choice to respond to such demands. As a summary of this chapter, two tables are given. Table I lists the labeled nucleosides reported to be available by chemical syntheses. Table II lists the NMR studies using labeled DNA oligomers that were prepared by chemical syntheses.

Hamatometacarpal fracture-dislocation: distinctive three dimensional computed tomographic appearance

We report here two fully documented cases of hamatometacarpal fracture-dislocation following trauma and treated in our hospital. In our cases, the patients suffered hamate fracture in association with metacarpal dislocation. In the first case, a dorsal oblique fracture of the hamate was associated with a dorsal dislocation of the base of the fourth metacarpal. In the second case, a dorsal oblique fracture of the hamate was not associated with a dorsal dislocation of the base of the fifth metacarpal. This diagnosis should be suspected on initial review of plain radiographs, which must include an oblique view because of diagnostic difficulty for this injury. We recommend three dimensional computed tomography (3D-CT) in any patient presenting with pain after blunt trauma to the hand to prevent in diagnosis. Open reduction and internal fixation of the fracture is indicated and relevant for displaced fracture.

Plasma membrane rafts play a critical role in HIV-1 assembly and release

HIV-1 particle production occurs in a series of steps promoted by the viral Gag protein. Although it is well established that assembly and release take place at the plasma membrane, the nature of membrane assembly sites remains poorly understood. We show here that Gag specifically associates with cholesterol-enriched microdomains ("rafts") at the plasma membrane. Kinetic studies demonstrate that raft association follows membrane binding, and the analysis of Gag mutants reveals that, whereas the N terminus of Gag mediates raft binding, this association is greatly enhanced by Gag-Gag interaction domains. We observe that depletion of cellular cholesterol markedly and specifically reduces HIV-1 particle production. Furthermore, treatment of virus-producing cells or virus particles with raft-disrupting agents significantly impairs virus infectivity. These results identify the association of Gag with plasma membrane rafts as an important step in HIV-1 replication. These findings may lead to novel strategies for suppressing HIV-1 replication in vivo.

[A case of carbamazepine intoxication with alpha coma and status epilepticus]

We report a 14-year-old girl with carbamazepine intoxication who developed alpha coma and status epilepticus. She fell into deep coma and developed frequent generalized convulsions. The EEG during coma showed diffuse alpha activity predominantly in the frontal area. Serum carbamazepine concentration was 42.8 micrograms/ml. The convulsions were suppressed by diazepam only transiently, and by midazolam completely. Although half a day had passed since carbamazepine ingestion, we could wash out much of drug remnants by gastric lavage. Thereafter, the serum concentration of carbamazepine decreased efficiently and the patient recovered dramatically without complication. Early diagnosis and appropriate treatments should improve the prognosis of carbamazepine intoxication.

[Clinical and bacteriological studies of ceftriaxone (CTRX) once daily administration in pediatric patients with respiratory tract infections]

Clinical studies of ceftriaxone (CTRX) were performed at a dose of 40 mg/kg once daily to evaluate its pharmacokinetics, and clinical and bacteriological efficacies in pediatric patients with respiratory tract infections. The following results were obtained. 1. Of 45 patients, clinical responses to CTRX were excellent in 34 (75.6%), good in 9 (20.0%) and poor in 2 (4.4%), indicating the overall efficacy rate of 95.6%. 2. Haemophilus influenzae (23 strains), Streptococcus pneumoniae (20 strains) and Moraxella catarrhalis (17 strains) were isolated from the patients as the main causative organisms. MIC90 of CTRX against these detected bacteria was < or = 0.06 microgram/ml with H. influenzae [beta-lactamase (-)/ABPC (S)], 0.25 microgram/ml with H. influenzae (BLNAR), 0.05 microgram/ml with PSSP, 1.0 microgram/ml with PISP/PRSP and 2.0 micrograms/ml with M. catarrhalis, respectively. 3. The eradication rate of causative organisms was 90.0% (27/30). 4. Serum levels of CTRX after administration of a 1-hour intravenous drip infusion of 40 mg/kg were investigated in 12 patients. Mean serum level at 24 hours after the administration was 9.4 +/- 2.8 micrograms/ml, which covered the level of MIC90 throughout the 24 hours. 5. No adverse reactions related to CTRX were observed. As the approved dosage of CTRX in pediatric patients is twice daily, while it is once daily in adults, there have been few reports on the efficacy of once-daily CTRX in pediatrics. According to the results of the study, it is suggested that once-daily CTRX for the pediatric patients with respiratory tract infections is useful. Further studies might be required to establish outpatient parenteral antibiotic therapy (OPAT) in pediatric infections.

Late male-killing phenomenon found in a Japanese population of the oriental tea tortrix, Homona magnanima (Lepidoptera: Tortricidae)

A female-biased sex ratio was found in the oriental tea tortrix, Homona magnanima (Lepidoptera: Tortricidae), in Tsukuba, Ibaraki, Japan. There was no difference in mean egg hatch between the all-female and normal strains. Greater than 50% mortality was observed in the all-female strain larvae, suggesting that female-only broods are produced as a result of late male-killing. The female-biased sex ratio was maternally inherited and maintained, even when females were backcrossed with males of the normal strain, thus implicating cytoplasmic parasitism as its cause. The phenomenon was persistent in the presence of antibiotics, and was not due to infection by agents that cause other male-killing phenomena, such as Rickettsia, Wolbachia, Spiroplasma, or protozoan parasites. When a homogenate of dead male larvae of the all-female strain was inoculated in normal-strain larvae, this male-killing trait was transmitted to the next generation; thus, its causative agent is probably transmitted horizontally as well.

Case report of serous ovarian tumor of borderline malignancy (Stage Ic) in a pregnant woman

We encountered a case of Stage Ic ovarian serous borderline malignancy in the first trimester of pregnancy. At laparotomy, spontaneous rupture of the capsule and a small amount of serous ascites was observed. Because of the laparotomy during pregnancy, correct staging of the tumor might not be performed. This case presented a major problem in deciding the treatment strategy, which are reported here together with some discussion of the literature on the preservation of fertility in borderline ovarian malignancy.