Flow cytometric evaluation on the age-dependent changes of testicular DNA contents in rats

An age-dependent cellular change of DNA contents in the testis of Sprague-Dawley rats was investigated by flow-cytometric method. Testicular cell suspensions at the age of 4, 5, 6, 7, 8, 10, 12, 16 and 26 weeks were prepared and stained with propidium iodide. The relative proportions in the number of mature and immature haploid (1n), diploid (2n), S-phase and tetraploid (4n) cells were calculated. The proportion in the number of mature haploid cells was sharply increased to the age of 10 weeks (about 38%), thereafter increased slightly to the level of 42% at the age of 26 weeks. The proportion of immature haploid cells was dramatically increased to the age of 6 weeks, then maintained at the level of 20 to 30% thereafter. The proportion of diploid cells was 64% at the age of 4 weeks, then decreased gradually through the age of 26 weeks. The proportion of S-phase cells was increased to the age of 4 weeks, then maintained at a plateau level to the age of 26 weeks. The proportion of tetraploid cells were about 26% at the age of 4 weeks, then decreased gradually to the age of 26 weeks. These results suggest that the proportions of testicular cells may depend on the age of the rat and that the flow cytometric method may be useful in the evaluation of the spermatogenic status with regard to accuracy and sensitivity.

Nucleophilic substitution at the imidoyl carbon atom: intermediate mechanistic and reactivity behavior between carbonyl and vinyl carbon substitution

Gas-phase nucleophilic substitution reactions at the imidoyl carbon have been investigated using chloride exchanges, Cl- + RY=CHCl right harpoon over left harpoon RY=CHCl + Cl- with Y = N and R = F, H or CH3, at the MP2, B3LYP and G2(+) levels using the MP2/6-311+G geometries. The results are compared with those for the vinyl (Y = CH) and carbonyl (Y = O) carbon substitution. The mechanism and reactivity of substitution at the imidoyl carbon are intermediate between those of carbonyl (SNpi) and vinyl carbon (SNsigma) substitution, which is directly related to the electronegativity of Y, CH < N < O. The prediction of competitive SNsigma with SNpi path for the imidoyl chloride is consistent with the S(N)1-like mechanism proposed for reactions in solution. The important factors in favor of an in-plane concerted SN2 (SNsigma) over an out-of-plane pi-attack (SNpi) path are (i) lower proximate sigma-sigma* charge-transfer energies (DeltaECT), (ii) stronger electrostatic stabilization (DeltaENCT), and (iii) larger lobe size on C(alpha) for the sigma*- than pi*-LUMO despite the higher sigma* than pi* level. The electron correlation energy effects at the MP2 level are overestimated for the relatively delocalized structure (S(N)pi TS) but are underestimated for the localized structure (SNsigma TS) so that the MP2 energies lead to a wrong prediction of preferred reaction path for the vinyl chloride. The DFT at the B3LYP level predicts correct reaction pathways but overestimates the electron correlation effects.

Mixed connective tissue disease associated with skin defects of livedoid vasculitis

A 21-year-old woman who had a 2-year history of mixed connective tissue disease (MCTD) developed rapidly evolving ulcers consistent with livedoid vasculitis (LV) in all distal extremities. She presented clinically with Raynaud's phenomenon, polyarthritis and swollen hands; serologically with high titres of ANA and anti-nRNP; and immunogenetically with HLA-DR4 and HLA-DR53. Although there was initial success in treatment except for the skin defects over the ankles, the patient died from disseminated intravascular coagulation. We suggest that LV may be a poor prognostic manifestation in MCTD.

Levels of interleukin-2, interferon-gamma, and interleukin-4 in bronchoalveolar lavage fluid from patients with Mycoplasma pneumonia: implication of tendency toward increased immunoglobulin E production

OBJECTIVE

In connection with the possible relationship between Mycoplasma infection and the onset of asthma, several studies have shown not only a high level of serum total immunoglobulin E (IgE) but also the production of IgE specific to Mycoplasma or common allergens during the course of Mycoplasma infection. It has been suggested that the balance of T helper type 1 (TH1)/T helper type 2 (TH2) immune response may regulate the synthesis of IgE. The objective of this study was to investigate the pattern of cytokine response (TH1 or TH2) during an episode of acute lower respiratory tract infection caused by Mycoplasma pneumoniae.

STUDY DESIGN

Using a bronchoalveolar lavage (BAL) with flexible bronchoscopy procedure, this study determined the levels of interleukin (IL)-2, interferon (IFN)-gamma (TH1), and IL-4 (TH2) in the supernatant of BAL fluid as well as the BAL cellular profiles of patients with Mycoplasma pneumonia (n = 14). These results were compared with those of patients with pneumococcal pneumonia (n = 12) or those of children with no identifiable airway infections (control group: n = 8).

RESULTS

The BAL cellular profile in the Mycoplasma pneumonia group was characterized by a high percentage of neutrophils and lymphocytes. A significantly increased level of IL-2 was found in both pneumonia groups, compared with the control group. In contrast, the IFN-gamma level was not different for the 3 groups. The level of IL-4 and ratio of IL-4/IFN-gamma were significantly elevated in the Mycoplasma pneumonia group, but not in the pneumococcal pneumonia group, compared with the controls.

CONCLUSIONS

IL-4 levels and IL-4/IFN-gamma ratios in BAL fluid are significantly higher in patients with Mycoplasma pneumonia than in patients with pneumococcal pneumonia or control participants. The BAL cytokine data suggest a predominant TH2-like cytokine response in Mycoplasma pneumonia, thus representing a favorable condition for IgE production.

Involvement of acetyl phosphate in the in vivo activation of the response regulator ComA in Bacillus subtilis

Development of genetic competence in Bacillus subtilis is regulated by ComP--ComA, a two-component signal transduction system. The response regulator ComA is primarily activated by ComP, a histidine kinase that mediates response to nutrient conditions and cell density, and the activated ComA is required for transcription of the srf operon, which is essential for the development of genetic competence and surfactin production. In this study we suggested that the ComA could also be activated by a small molecule phospho-donor, acetyl phosphate. Examination of srfA-lacZ expression indicated that a significant amount of srfA expression still occurs in the comP mutant during growth in a sporulation medium containing excess glucose. Analysis of a comP and pta mutant suggests that srfA activation seen in the comP mutant is dependent on the expression of pta, which encodes phosphotransacetylase (Pta). As Pta is responsible for the catalysis for conversion of acetyl coenzyme A to acetyl phosphate, we conclude that the expression of srfA seen in the comP mutant is mainly due to the activation of ComA by acetyl phosphate.

Gene medicine : a new field of molecular medicine

Gene therapy has emerged as a new concept of therapeutic strategies to treat diseases which do not respond to the conventional therapies. The principle of gene therapy is to introduce genetic materials into patient cells to produce therapeutic proteins in these cells. Gene therapy is now at the stage where a number of dinical trials have been carried out to patients with gene-deficiency disease or cancer. Genetic materials for gene therapy are generally composed of gene expression system and gene delivery system. For the dinical application of gene therapy in a way which conventional drugs are used, researches have been focused on the design of gene delivery system which can offer high transfection efficiency with minimal toxicity. Currently, viral delivery systems generally provide higher transfection efficiency compared with non-viral delivery systems while non-viral delivery systems are less toxic, less immunogenic and manufacturable in large scale compared with viral systems. Recently, novel strategies towards the design of new non-viral delivery system, combination of viral and non-viral delivery systems and targeted delivery system have been extensively studied. The continued effort in this area will lead us to develop gene medicine as 'gene as a drug' in the near future.

Brain succinic semialdehyde dehydrogenase: identification of reactive lysyl residues labeled with pyridoxal-5'-phosphate

An NAD+ dependent succinic semialdehyde dehydrogenase from bovine brain was inactivated by pyridoxal-5'- phosphate. Spectral evidence is presented to indicate that the inactivation proceeds through formation of a Schiff's base with amino groups of the enzyme. After NaBH(4) reduction of the pyridoxal-5'-phosphate inactivated enzyme, it was observed that 3.8 mol phosphopyridoxyl residues were incorporated/enzyme tetramer. The coenzyme, NAD+, protected the enzyme against inactivation by pyridoxal-5'-phosphate. The absorption spectrum of the reduced and dialyzed pyridoxal-5'-phosphate-inactivated enzyme showed a characteristic peak at 325 nm, which was absent in the spectrum of the native enzyme. The fluorescence spectrum of the pyridoxyl enzyme differs completely from that of the native enzyme. After tryptic digestion of the enzyme modified with pyridoxal-5'-phosphate followed by [3H]NaBH4 reduction, a radioactive peptide absorbing at 210 nm was isolated by reverse-phase HPLC. The sequences of the peptide containing the phosphopyridoxyllysine were clearly identical to sequences of other mammalian succinic semialdehyde dehydrogenase brain species including human. It is suggested that the catalytic function of succinic semialdehyde dehydrogenase is modulated by binding of pyridoxal-5'-phosphate to specific Lys(347) residue at or near the coenzyme-binding site of the protein.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic liver: accuracy of ultrasonography in transplant patients

The purpose of this study was to assess the usefulness of ultrasonography in the detection of hepatocellular carcinomas and dysplastic nodules in patients with liver cirrhosis. Pretransplantation sonograms in 52 patients with liver cirrhosis who underwent orthotopic liver transplantation were evaluated retrospectively. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted liver specimens and compared with pretransplantation ultrasonographic results. Eighteen hepatocellular carcinomas in 16 patients and 20 dysplastic nodules in 11 patients were present in the explanted livers. The size of hepatocellular carcinomas ranged from 0.6 to 5.0 cm (mean, 2.1 cm) in diameter, and that of dysplastic nodules ranged from 0.5 to 1.7 cm (mean, 1.0 cm) in diameter. Pretransplantation ultrasonography enabled detection of 6 of 18 hepatocellular carcinoma and 0 of 20 dysplastic nodule lesions; lesion detection sensitivity for hepatocellular carcinomas and dysplastic nodules was 33% and 0%, respectively. Patient sensitivity and specificity for hepatocellular carcinomas were 38% (6 of 16) and 92% (33 of 36), and those for dysplastic nodules were 0% and 95% (39 of 41), respectively. On the basis of our results, ultrasonography is insensitive for detection of hepatocellular carcinomas and dysplastic nodules in patients with advanced liver cirrhosis.

Simultaneous determination of 226Ra and 210Pb in groundwater and soil samples by using the liquid scintillation counter-suspension gel method

A method for the simultaneous determination of 226Ra and 210Pb in groundwater and soil samples by liquid scintillation counting was developed. Radium and lead were separated together from the samples as Ba(Ra) x PbSO4 co-precipitate, which was centrifuged and dissolved with 0.1 M EDTA solution (pH 9.0). Radium was separated as Ba(Ra)SO4 co-precipitate by adding ammonium sulfate and adjusting the pH of the solution to 4.2. Lead remaining in the solution was separated as PbSO4 precipitate by adding 9 M sulfuric acid. These Ba(Ra)SO4 and PbSO4 precipitates were purified with EDTA solution and used for measurement. To save time and to make counting samples simpler, direct counting of Ba(Ra)SO4 and PbSO4 precipitates instead of the phosphoric acid fusion method was attempted. Ba(Ra)SO4 and PbSO4 precipitates were suspended in the scintillation gel, and measured. Two liquid scintillation cocktails, Instagel XF and UltimaGold AB were used to prepare the counting samples. A mixture of water (40%), Instagel XF (40%) and UltimaGold AB (20%) formed a stable gel. Activities of 226Ra and 210Pb were calculated from the alpha spectrum of Ba(Ra)SO4 and beta spectrum of PbSO4, respectively. The long-term stability of the suspension gel was good. The analytical results of 226Ra and 210Pb in spiked groundwater samples were in good agreement with the known concentrations of 226Ra and 210Pb. The analytical values of 226Ra and 210Pb in the soil reference samples were within 11.5 and 1.6% of the relative error from the reference values, respectively.

Preparation and evaluation of biphenyl dimethyl dicarboxylate microemulsions for oral delivery

To improve the solubility and bioavailability of poorly water-soluble biphenyl dimethyl dicarboxylate (BDD), a drug used in treating liver diseases, a premicroemulsion concentrate composed of oil, surfactant, and cosurfactant for oral administration of BDD was prepared, and its physicochemical properties and the pharmacokinetic parameters of BDD were evaluated. Among the non-ionic surfactants and oils studied, Tween 80, which led to the highest solubility of BDD (109.7 microg/ml), and Neobee M-5((R)) were chosen for preparing a premicroemulsion concentrate. At the 2:1 ratio of Tween 80 to Neobee M-5((R)), the solubility of BDD increased 7-fold compared with that at the ratio of 1:4. The solubility of BDD was further improved by the addition of triacetin used as a cosurfactant. Droplet size of BDD microemulsion comprising Tween 80 and Neobee M-5((R)) at the ratio of 2:1, and 35% of triacetin, was kept constant both in distilled water and artificial gastric fluid without pepsin (pH 1.2) throughout 120-min incubation period. BDD in premicroemulsion concentrate rapidly dissolved whereas the mixture of BDD and calcium-carboxymethylcellulose (Ca-CMC) (2:1) and BDD powder hardly dissolved during 120-min incubation. About 50% of BDD in premicroemulsion concentrate dissolved within 10 min. AUC(0-->24 h) and the mean maximum plasma level (C(max)) of BDD after oral administration of premicroemulsion concentrate in rats were 5- and 9.8-fold higher, respectively, than those of BDD with Ca-CMC. These results demonstrate that premicroemulsion concentrate of BDD composed of Tween 80 and Neobee M-5((R)) at the ratio of 2:1, and 35% of triacetin, greatly enhances the bioavailability of BDD after the dose, possibly due to the increase in solubility and immediate dispersion of drug in the gastrointestinal tract. Thus, this system may provide a useful dosage form for oral intake of a water-insoluble drug, BDD.

Effects of vehicles and enhancers on transdermal delivery of melatonin

For a more effective transdermal delivery of melatonin (MT), the effects of vehicles and enhancers on its skin permeation and lag time were evaluated. Skin permeation study was conducted in Franz diffusion cells using excised hairless mouse skins. MT was analyzed by HPLC. As vehicles, ethanol (EtOH), polyethylene glycol 400 (PEG), or propylene glycol (PG) was used alone or mixed with a phosphate buffer. Binary vehicles (EtOH/buffer, PEG/buffer, PG/buffer) showed different effects on the skin permeation of MT and its lag time. Compared with the buffer alone, the PEG/buffer shortened the lag time of MT but reduced its skin permeation. EtOH/buffer significantly increased the flux of MT but prolonged the lag time with the content of EtOH. PG/buffer did not affect the lag time but slightly increased the skin permeation of MT at the higher content of PG (> or =80%). These results indicate that the composition of vehicles exerts significant influence but it per se might have limitation in modulating the transdermal delivery of MT. Next, one tested whether fatty acids could more effectively enhance the skin permeation of MT and shorten its lag time. Given the influence of vehicles on both permeation and lag time, PG was used as a vehicle for fatty acids. The permeation-enhancing effects of saturated fatty acids increased in the following order: C10>C12>C14>C16>C18. The saturated fatty acid, however, did not significantly shorten the lag time regardless of the carbon chain length. Meanwhile, similar to saturated lauric acid (C12), unsaturated oleic acid (C18) dramatically enhanced the skin permeability coefficient of MT more than 950-fold over the effect of PG alone. Moreover, oleic acid showed the shortest lag time (2.1 h). The results suggest that oleic acid in a suitable vehicle could more effectively enhance the skin permeation of MT and shorten its lag time than did the vehicles of various compositions.

Natural radionuclides contents and radon exhalation rates in building materials used in South Korea

The natural radionuclide (226Ra, 232Th and 40K) contents of building materials commonly used in South Korea have been determined by a gamma ray spectroscopy system using a high purity germanium detector. The radon exhalation rates and emanation coefficients of building materials have also been studied. The average concentrations of 226Ra, 232Th and 40K in building materials were in the range of 6.47-271 Bq.kg-1, N.D.-89.9 Bq.kg-1 and 16.8-1081 Bq.kg-1, respectively. The average radon exhalation rates and emanation coefficients were in the range of 0.0061-0.2404 Bq.kg-1.h-1 and 2.39-11.5%, respectively.

Cigarette smoking negatively affects healing response following flap debridement surgery

BACKGROUND

The purpose of the present parallel design, controlled clinical trial was to evaluate the treatment outcome following flap debridement surgery (FDS) in cigarette smokers compared to non-smokers.

METHODS

After initial therapy, 57 systemically healthy subjects with moderate to advanced periodontitis who presented with one area (at least 3 teeth) where surgery was required were selected. Twenty-eight patients (mean age: 39.6 years, 20 males) were smokers (> or = 10 cigarettes/day); 29 patients (mean age: 43.9 years, 7 males) were non-smokers. Full-mouth plaque (FMP) and bleeding on probing (BOP) scores, probing depth (PD), clinical attachment level (CAL), and recession depth (RD) were assessed immediately before and 6 months following surgery. Only sites with presurgery PD > or = 4 mm were used for statistical analysis.

RESULTS

Presurgery FMP and BOP were similar in smokers and non-smokers and significantly decreased postsurgery in both groups. Overall, PD reduction and CAL gain were greater, although not significantly, in non-smokers (2.4 +/- 0.9 mm and 1.6 +/- 0.7 mm, respectively) than in smokers (1.9 +/- 0.7 mm and 1.2 +/- 0.7 mm, respectively). For moderate sites (PD 4 to 6 mm), no significant differences in PD and CAL changes were found between groups. For deep sites (PD > or = 7 mm), PD reduction was 3.0 +/- 1.0 mm in smokers and 4.0 +/- 0.8 mm in non-smokers, and CAL gain amounted to 1.8 +/- 1.1 mm in smokers and 2.8 +/- 1.0 mm in non-smokers (P = 0.0477). In smokers, 16% of deep sites healed to postsurgery PD values < or = 3 mm as compared to 47% in non-smokers (P = 0.0000); 58% of deep sites in smokers showed a CAL gain > or = 2 mm, as compared to 82% in non-smokers (P = 0.0000).

CONCLUSIONS

Results of the study indicated that: 1) FDS determined a statistically significant PD reduction and CAL gain in patients with moderate to advanced periodontitis; 2) smokers exhibited a trend towards less favorable healing response following FDS compared to non-smokers, both in terms of PD reduction and CAL gain; and 3) this trend reached clinical and statistical significance at sites with initial deep PD.

Pretreatment of whole blood for use in immunochromatographic assays for hepatitis B virus surface antigen

Immunochromatographic assays (ICAs) are also referred to as rapid tests, since they are simple and the results can be obtained within minutes after manually loading a few drops of a sample into each sample well of the test device. However, whole blood cannot be tested with ICA kits due to the visual hindrance caused by the color of red blood cells (RBCs), unless a cell-removing device such as a filter is mounted on the kits. Thus, when testing with blood, the advantage of the ICA kit is lost because of the additional time and machines required to coagulate and separate whole blood before preparing the serum. To overcome this limitation, whole-blood samples were added to a pretreatment solution to decolor the RBCs; the resulting mixtures were then loaded into the sample wells of the test device. The pretreating solution was composed of hydrogen peroxide (H(2)O(2)) to decolor the RBCs, Sag 471 (Osi Specialties) to restrain the mixture from vigorous foaming, sodium azide (NaN(3)) to inhibit the enzyme, which generates excessive foam at the beginning of decolorization, and EDTA as a chelating agent. As a result of this pretreatment, whole blood could be used with the ICA kit without reducing its simplicity and rapidity.

Mammary gland tumor in transgenic mice expressing targeted beta-casein/HPV16E6 fusion gene

The human papillomaviruses (HPV)-16 and HPV-18 referred to as high-risk HPVs are strongly associated with anogenital malignancies as well as benign epithelial cysts. It has been demonstrated that transgenic mice carrying HPV-16 E6-E7 under the control of the MMTV LTR developed malignant tumors including salivary gland carcinoma, lymphoma, skin histiocytomas and testicular tumors in a non-mammary gland specific manner. Another regulatory unit of rat beta-casein gene can confer the expression of fusion gene preferentially in the mammary glands of transgenic mice in a developmentally regulated manner. In order to generate mammary tumor formation in transgenic mice directing HPV16E6 gene alone into the mammary gland, this regulatory unit was fused to the E6 gene of HPV-16 type to constructing fusion gene. By screening 51 newborn founder transgenic mice, three mice carrying transgenes were identified. One line termed TG32 developed in a mammary gland tumor with large subcutaneous mass in the left rib region at 17 months of age. The levels of E6 transcript in the mass-tumor of TG32 line were lower than those in non-tumor mammary gland of identical TG32 and of TG250. In each tissue of TG32 line, high expression of E6 transcript was detected both in the mammary gland and brain. Histological analysis showed that cells from mammary gland tumor of the TG32 line had also hyperplasia appearance, with irregular or increased total number of mitotic rate. These observations suggest that developing phenotype and the level of E6 transcripts in the process of malignant transformation may have different mechanisms involving the capacity to bind and destabilize p53, although for confirmation it is necessary to investigate many more transgenic mice.

Atopic status and level of bronchial responsiveness in parents of children with acute bronchiolitis

To examine whether children with a genetic predisposition to asthma are more likely to be afflicted with bronchiolitis, we studied 122 parents of infants who were hospitalized with the diagnosis of acute bronchiolitis (index group) and 120 parents of children who had never suffered from this disease (control group). The parents underwent bronchial challenge testing with methacholine and skin prick testing with common airborne allergens, and gave blood specimens for measurement of serum total IgE. There was no difference in atopic status, as assessed by the prevalence of atopy (at least one positive response to the allergens tested) or by serum total IgE levels, between index and control parents. The prevalence of bronchial hyperresponsiveness (BHR) (concentration of methacholine causing a 20% reduction in forced expiratory volume in 1 sec [PC20] < 18 mg/mL) was higher in index parents than in control parents (17.2% vs. 7.5%, p = 0.02). Bronchial responsiveness (BR) index was significantly higher in index parents than in control parents (1.135 +/- 0.088 vs. 1.104 +/- 0.071, p < 0.01). Parents of children who were hospitalized with acute bronchiolitis showed a higher level of BR, but not atopy. This suggests that in terms of BHR, there may be a genetic predisposition to the development of bronchiolitis.

Steaming of ginseng at high temperature enhances biological activity

The present study was performed to evaluate the effect of steaming ginseng at a temperature over 100 degrees C on its chemical constituents and biological activities. Raw ginseng was steamed at 100, 110, and 120 degrees C for 2 h using an autoclave. The ginseng steamed at 120 degrees C was more potent in its ability to induce endothelium-dependent relaxation. Steaming the raw ginseng at 120 degrees C also remarkably increased the radical-scavenging activity. Ginsenosides F(4), Rg(3), and Rg(5), which were not present in raw ginseng, were produced after steaming. Ginsenosides Rg(3) and Rg(5) were the most abundant ginsenosides in the ginseng steamed at 120 degrees C, accounting for 39% and 19% of all ginsenosides, respectively.

Technical aspects of performing lymphoscintigraphy: optimization of methods used to obtain images

Sentinel node detection is an important part of the clinical management of newly diagnosed melanoma. Now there is a similar or even greater enthusiasm for sentinel node evaluation in patients with breast carcinoma. However, controversies exist regarding the dose, volume, and route of administration. Even the role of lymphoscintigraphy itself, in contrast to using only a hand-held gamma probe during surgery for sentinel node detection, is being debated. Nevertheless, many centers and surgeons find that lymphoscintigraphy images are valuable in the treatment of patients and they use lymphoscintigraphy as a guide during surgery and to confirm the results obtained with the hand-held probe. Centers just beginning to use lymphoscintigraphy may find the images especially useful. Given this fact, the authors wanted to define the practical and technical aspects of performing lymphoscintigraphy in patients with breast cancer and examined various methods for the optimization of the technique of image acquisition. The suggested technique is generally free of the controversies noted above and applies to most patients. It includes various maneuvers that aim to improve the rate of sentinel node visualization using the gamma camera and the accuracy of node detection. The recommendations presented here should prove useful for both those experienced and for those centers just beginning to use the technique of lymphoscintigraphy.

Genetic structure and functional implication of the fcb gene cluster for hydrolytic dechlorination of 4-chlorobenzoate from Pseudomonas sp. DJ-12

The fcb gene cluster responsible for the hydrolytic dechlorination of 4-chlorobenzoate (4CBA) was cloned from the chromosomal DNA of Pseudomonas sp. DJ-12, and its nucleotide sequence analyzed. The gene cluster was organized in the order fcbB-fcbA-fcbT1-fcbT2-cbT3-fcbC, which is different from that reported in other bacteria. A promoter-like sequence (-35 and -10 region) is located upstream of the fcbB gene and putative ribosome-binding sequences were found upstream of the respective orfs. A stem-loop transcription terminator structure is found downstream of fcbC. This suggests that the six orfs are transcribed into a polycistronic mRNA. The FcbA, FcbB, and FcbC enzymes for dechlorination of 4CBA have a relationship in common with the enzymes involved in fatty acid metabolism on the basis of their deduced amino acid sequences. The proteins encoded by fcbT1, fcbT2, and fcbT3 show similarity to those encoded by dctP, dctQ, and dctM of Rhodobacter capsulatus respectively, which encode transporter proteins for C4-dicarboxylate. It is likely, therefore, that these proteins of DJ-12 play a role in transport of 4CBA into the cell.

Bronchoalveolar lavage cellular composition in acute asthma and acute bronchiolitis

OBJECTIVE

To compare cellular inflammation in the airways between acute bronchiolitis and asthma.

STUDY DESIGN

Using a bronchoalveolar lavage with flexible bronchoscopy procedure, we investigated the cellular constituents of BAL fluid in children with acute exacerbation of asthma (n = 18) and infants with acute bronchiolitis caused by respiratory syncytial virus (n = 20). These results were compared with those of healthy control subjects (n = 14).

RESULTS

Total lavage fluid recovered was similar in all groups. The total cell numbers were highest in the bronchiolitis group. The BAL cellular profile in the asthma group was characterized by a higher median (interquartile range) ratio of eosinophils (2.4% [1.6%-9.5%]; P <.01) than in the bronchiolitis group (0% [0%-0%]) or the control group (0% [0%-0%]). Neutrophil ratio was higher in the bronchiolitis group (40.0% [26.5%-50.0%]; P <.01), with no difference found between the asthma group (3.3% [2.0%-7.9%]) and the control group (2.0% [0.8%-5.5%]).

CONCLUSIONS

Asthma and acute bronchiolitis are characterized by an elevated cellular percentage of eosinophils and neutrophils, respectively, in bronchoalveolar lavage fluid.

Development of omeprazole buccal adhesive tablets with stability enhancement in human saliva

To develop an omeprazole buccal adhesive tablet, the absorption of omeprazole solutions from human oral cavity was evaluated and the physicochemical properties such as the bioadhesive forces of various omeprazole tablet formulations composed of bioadhesive polymers and alkali materials, and the stability of omeprazole tablets in human saliva were investigated. About 23% of the administered dose was absorbed from the oral cavity at 15 min after the administration of omeprazole solutions (1 mg/15 ml). A mixture of sodium alginate and HPMC was selected as the bioadhesive additive for the omeprazole tablet. Omeprazole tablets prepared with bioadhesive polymers alone had the bioadhesive forces suitable for buccal adhesive tablets, but the stability of omeprazole in human saliva was not satisfied. Among alkali materials, only magnesium oxide could be an alkali stabilizer for omeprazole buccal adhesive tablets due to its strong waterproofing effect. Two tablets composed of [omeprazole/sodium alginate/HPMC/magnesium oxide (20/24/6/50, mg/tab)] and [(20/30/0/50, mg/tab)] were suitable for omeprazole buccal adhesive tablets which could be attached to human cheeks without collapse and could be stabilized in human saliva for at least 4 h. It was concluded that these two formulae were potential candidates for the subject of further study for the development of omeprazole buccal adhesive tablets.

Detection of major putative periodontopathogens in Korean advanced adult periodontitis patients using a nucleic acid-based approach

BACKGROUND

Although extensive microbial analyses have been performed from subgingival plaque samples of periodontitis patients, systematic analysis of subgingival microbiota has not been carried out in a Korean population so far. The purpose of this study was to describe the prevalence of major putative periodontopathogens in Korean patients by culture-independent methods.

METHODS

A total of 244 subgingival plaque samples (5 sites in each participant) were taken from 29 advanced adult periodontitis (AP) patients and 20 periodontally healthy subjects. AP samples were obtained from the 4 deepest periodontal pockets (> or =6 mm probing depth [PD]) and 1 healthy site (< or =3 mm PD) in each patient. Polymerase chain reaction (PCR) of 16S ribosomal DNA (rDNA) of subgingival plaque bacteria was performed with eubacterial primers. Aliquots of PCR products were then applied on nylon membranes and hybridized with specific oligonucleotide probes labeled with digoxigenin.

RESULTS

All diseased sites harbored Fusobacterium sp., while Porphyromonas gingivalis, Treponema sp., and Bacteroides forsythus were detected in more than 96% of 116 diseased sites. Peptostreptococcus micros, Actinobacillus actinomycetemcomitans, and Prevotella intermedia were present in 82%, 74%, and 71% of diseased sites, respectively. In sites of periodontally healthy subjects, Fusobacterium sp. was present in the highest proportion (58%). Treponema sp., P. gingivalis, and B. forsythus were detected in 22%, 18%, and 18% of healthy sites, respectively. P. micros, P. intermedia, and A. actinomycetemcomitans were found in 8%, 2%, and 1% of healthy sites, respectively. The prevalence of the periodontopathogens, with the exceptions of Fusobacterium sp. and B. forsythus, was significantly higher in the healthy sites of periodontitis subjects than in the healthy sites of periodontally healthy subjects (P <0.05).

CONCLUSIONS

Using highly sensitive methods relying on 16S ribosomal RNA-based oligonucleotide probes, we confirmed the strong association of 7 putative periodontopathogens with AP patients in a Korean population. With the exceptions of Fusobacterium sp. and B. forsythus, all the periodontopathogens were significantly more associated with the healthy sites of periodontitis subjects than in the healthy sites of periodontally healthy subjects.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers: accuracy of helical CT in transplant patients

OBJECTIVE

The purpose of this study was to evaluate the diagnostic efficacy of three-phase helical dynamic CT in the detection and characterization of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers.

SUBJECTS AND METHODS

Three-phase helical dynamic CT in 41 patients with liver cirrhosis was evaluated prospectively before orthotopic liver transplantation. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted livers and compared with pretransplantation CT findings.

RESULTS

Examination of the explanted livers revealed 21 hepatocellular carcinomas in 15 patients and 23 dysplastic nodules in 10 patients. The size of the hepatocellular carcinomas was 0.6-5. 0 cm (mean, 1.9 cm), and that of the dysplastic nodules was 0.7-2.0 cm (mean, 1.0 cm). The use of helical dynamic CT enabled detection of 15 of 21 hepatocellular carcinomas (sensitivity, 71%) and nine of 23 dysplastic nodules (sensitivity, 39%). Patient sensitivity and specificity in the detection of hepatocellular carcinomas were 80% (12/15) and 96% (25/26), respectively, and for dysplastic nodules, 50% (5/10) and 97% (30/31), respectively.

CONCLUSION

Three-phase helical dynamic CT is relatively insensitive for detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers, especially for dysplastic nodules and hepatocellular carcinomas smaller than 2 cm.

Ventilation-perfusion-chest radiography match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent

PURPOSE

The authors' goal was to determine whether the prevalence of pulmonary embolism in patients with matching ventilation-perfusion (V-Q) defects and chest radiographic opacities differs depending on the degree of perfusion deficit (absent versus decreased).

METHODS

The authors performed a retrospective analysis of the data obtained from the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study. In 233 patients, angiograms were of diagnostic quality for 275 lung zones that showed matching V-Q defects and chest radiographic opacities (triple matches). Of these, V-Q scans and chest radiographs from 217 patients with triple matches in 255 lung zones were retrieved and reviewed. Areas corresponding to chest radiographic opacities were scored as having either decreased perfusion or absent perfusion by consensus. Information regarding the presence or absence of pulmonary embolism in corresponding lung zones was obtained from the PIOPED database.

RESULTS

The overall prevalence of pulmonary embolism in all lung zones with triple matches was 27% (69 of 255). Of the 255 areas of triple matches, the perfusion was decreased in 153 (60%) and absent in 102 (40%). The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion was 13% (20 of 153) and 48% (49 of 102), respectively (P = 0.0001 by the chi-square test). When these were divided further by lung zones, triple matches with decreased perfusion and triple matches with absent perfusion in the upper-middle lung zone were associated with a prevalence of 0% (O of 44), and 25% (9 of 36), respectively. The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion in the lower lung zone was 18% (20 of 109), and 61% (40 of 66), respectively.

CONCLUSIONS

A V-Q/chest radiographic match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent. The overall prevalence of pulmonary embolism associated with all triple matches in all lung zones varied from very low (0% in this series) to upper intermediate (61 %), depending on whether perfusion was decreased or absent and also on the location of the triple match.

Cloning and nucleotide sequence analysis of xylE gene responsible for meta-cleavage of 4-chlorocatechol from Pseudomonas sp. S-47

Pseudomonas sp. S-47 expresses catechol 2,3-dioxygenase (C230) catalyzing the conversion of 4-chlorocatechol (4CC) as well as catechol to 5-chloro-2-hydroxymuconic semialdehyde and 2-hydroxymuconic semialdehyde, respectively, through meta-ring cleavage. The xylE gene encoding C230 for meta-cleavage was cloned from strain S-47 and its nucleotide sequence was analyzed. The pRES101 containing the xylE gene exhibited high C230 activity toward catechol and 4CC without altering the substrate specificity from natural strain. The xylE gene was composed of 924 bp and encoded polypeptide of molecular mass 35 kDa containing 307 amino acids. A deduced amino acid sequence of the C230 from strain S-47 exhibited over 80% identity with those of Pseudomonas putida mt-2, Pseudomonas putida G7, and Pseudomonas sp. CF600. However, it shows below 45% identity with those of Pseudomonas cepacia LB400 and Pseudomonas sp. KKS102. The C230 of strain S-47 was conserved in the amino acids (His150, His214, Glu261) for metal binding ligands and those (His199, His242, and Tyr251) for catalytic sites. Therefore, Pseudomonas sp. S-47 can be explained as acting by degrading catechol as well as 4CC by xylE-encoding C230 which was fused by N domain of nahH and C domain of dmpB from other Pseudomonas strains.

Refinement of the positive predictive value of gallbladder nonvisualization after morphine administration for acute cholecystitis based on the temporal pattern of common bile duct activity

The authors previously reported two major patterns in the time-activity curve of the common hepatic bile duct (BD) after morphine administration in patients with gallbladder nonvisualization. The first pattern consists of a gradual increase in BD activity (of variable duration) occurring during a simultaneous decrease in liver parenchymal activity (BD increase), representing the physiologic effects of morphine administration. The second pattern consists of a continuous decrease in BD activity that parallels the activity in the liver parenchyma (BD decrease), representing lower or no physiologic effects of morphine administration. The authors hypothesize that gallbladder nonvisualization associated with a continuous decrease in BD activity after morphine administration will have a lower positive predictive value (PPV) for acute cholecystitis than gallbladder nonvisualization associated with an increase in BD activity.

METHODS

Thirty-six patients who had morphine-augmented cholescintigraphy were divided into two groups: 19 with BD increase after morphine administration and 17 with BD decrease.

RESULTS

Of the 36 patients, 22 had acute cholecystitis. The positive predictive value (PPV) of gallbladder nonvisualization was 61%. All of the remaining 14 had chronic cholecystitis. Of 19 patients with BD increase, 15 had acute cholecystitis (PPV = 79%), whereas only 7 of 17 patients with BD increase (PPV = 41 %) had acute cholecystitis (P = 0.023 by the one-tailed and 0.038 by the two-tailed Fisher exact tests).

CONCLUSIONS

Gallbladder nonvisualization after morphine administration with the pattern of BD decrease is not as reliable (intermediate probability in this series) for the diagnosis of acute cholecystitis as is nonvisualization of the gallbladder in patients with a pattern of BD increase (high probability).

Induction of stress shock proteins DnaK and GroEL by phenoxyherbicide 2,4-D in Burkholderia sp. YK-2 isolated from rice field

The purpose of this work was to investigate the induction of stress shock proteins in Burkholderia sp. YK-2 in response to the phenoxyherbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The stress shock proteins, which contribute to the resistance of the cytotoxic effect of 2,4-D, were induced at different 2,4-D concentrations in exponentially growing cultures of Burkholderia sp. YK-2. This response involved the induction of a 43-kDa DnaK and 41-kDa GroEL proteins, characterized by SDS-PAGE and Western blot by use of the anti-DnaK and anti-GroEL monoclonal antibodies. The total stress shock proteins were analyzed by 2-D PAGE. Survival of Burkholderia sp. YK-2 with time in the presence of different concentrations of 2,4-D was monitored, and viable counts paralleled the induction of the stress shock proteins in this strain.

Use of radioimmunoscintigraphy with indium-111-labeled CYT-356 (ProstaScint) scan for evaluation of patients for salvage brachytherapy

PURPOSE

Indium 111 capromab pendetide radioimmunoscintigraphy (ProstaScint) has been used to detect occult recurrent carcinoma after radical prostatectomy.

MATERIALS AND METHODS

We evaluated the role of ProstaScint in 24 men with rising prostate-specific antigen (PSA) level following definitive radiation therapy to differentiate between local and distant recurrence in this patient population.

RESULTS

ProstaScint scan detected prostatic uptake only in 16 patients, extraprostatic uptake in 5, both prostatic and extraprostatic uptake in 1, and no uptake in 2. Ten of 21 patients with prostatic uptake had positive biopsies, 5 had negative biopsies, and 6 were not biopsied. Two of the three patients with negative scans had positive biopsies, and the third patient was not biopsied. Three patients had evidence of osseous metastasis on radionuclide bone scan, two corresponding to the sites detected on ProstaScint. All three patients had abnormal uptake beyond the prostatic fossa with (n =2) or without (n = 1) prostatic uptake. There were no positive bone scans in patients without extraprostatic uptake on ProstaScint.

CONCLUSIONS

ProstaScint scan is useful in detecting occult recurrence outside the prostate in patients with rising PSA following radiation therapy. Compared to data from radical prostatectomy, ProstaScint scans in these patients reveal a higher prevalence of abnormal uptake in the prostate and less frequent extraprostatic uptake.

Development of terfenadine-pseudoephedrine double-layer tablet dissolution-equivalent to core tablet

The terfenadine-pseudoephedrine dosage form discussed here is the sustained-release core tablet composed of outer (fast-release) and inner (sustained-release) layers. To develop the double-layer tablet dissolution-equivalent to a core tablet, the fast-release and sustained-release layers were prepared using various disintegrants and polymers, respectively. The layer composed of terfenadine/pseudoephedrine/lactose/cornstarch/sodium bicarbonate/hydroxypropylcellulose (HPC)/sodium lauryl sulfate/microcrystalline cellulose (60/10/90/30/20/1/40/1/293 mg), which gave the fast disintegration time and high dissolved amounts of drugs, was selected as the fast-release layer. The dissolved amounts of pseudoephedrine from sustained-release layers increased more with a smaller ratio of ethylcellulose and hydroxypropylmethylcellulose (HPMC). Dissolution mechanism analysis showed the release of pseudoephedrine was proportional to the square root of time, indicating that drug might be released from the layers by Fickian diffusion. The layer composed of pseudoephedrine/ethylcellulose/HPMC (110/30/155 mg), which had similar dissolution amounts of pseudoephedrine as the inner layer of a core tablet, was selected as the sustained-release layer. Furthermore, the dissolved amounts of drugs from the core and double-layer tablets had deviations of less than 5% against the average dissolved amounts of drugs at each time. There was no significant difference between the dissolved amounts of drugs from these tablets at each time in pH 1.2, 4.0, and 6.8 (P > .05). Our results suggest that this double-layer tablet was a dissolution equivalent to the core tablet.

Nitric oxide and carbon monoxide have a stimulatory role in the hypothalamic-pituitary-adrenal response to physico-emotional stressors in rats

We tested the hypothesis that nitric oxide and carbon monoxide, which are produced in the brain by nitric oxide synthase (NOS) and heme oxygenase (HO), modulate the hypothalamic-pituitary-adrenal response to physico-emotional stressors by acting at the hypothalamus. Accordingly, we determined 1) whether the intracerebroventricular (icv) injection of NOS or HO inhibitors at doses that were confined to the brain attenuated electroshock-induced ACTH release; and 2) whether the decreases in this ACTH response were concurrent with decreases in NOS or HO activity levels at the hypothalamus. Icv injection of the NOS inhibitor Nomega-nitro-L-arginine-methylester (L-NAME; 50 microg) or the HO inhibitor tin protoporphyrin (SnPP; 20-25 microg) significantly blunted the plasma ACTH response to a 45-min session of intermittent electroshocks. Importantly, in these same animals there were concurrent decreases in hypothalamic NOS or HO activities, respectively. There were little or no effects of these inhibitors on anterior pituitary NOS or HO activities, indicating that there was only minimal leakage of the drug from the brain after icv administration. The specificity of action of these inhibitors was confirmed by the fact that SnPP did not affect NOS activity, and L-NAME did not affect HO activity. Finally, L-NAME produced no effect, whereas SnPP produced only transient increases in blood pressure, suggesting that these inhibitors do not affect activity indirectly through alterations in blood pressure. These data support the hypothesis that in the whole animal, both NO and CO exert a stimulatory influence on the acute ACTH response to physico-emotional stressors, and that the hypothalamus is the critical site of their actions.

Environmental distribution and behavior of 3H and 14C around Wolsong Nuclear Power Plants

To estimate of the dispersion trend of 3H and 14C discharged from the Wolsung Nuclear Power Plants, the present level of 3H and 14C in environmental samples in the vicinity of the Wolsong site was studied. Tree-ring cellulose analyses were carried out for retrospective evaluation of 3H and 14C in the environment around the Wolsong Nuclear Power Plants. 3H released from the Wolsong Nuclear Power Plants has affected an area up to a 25-km radius from the site, while almost all 14C was deposited within a 2-km radius, reaching to a natural level over 2 km. Organically bound tritium concentrations in tree rings were strongly correlated with the gaseous tritium discharge rate, while delta14C (excess) in tree rings ranged from 204 per thousand to 460 per thousand, which did not significantly vary with year.

Comparison of in vivo fate and immunogenicity of hepatitis B surface antigen incorporated in cationic and neutral liposomes

To compare cationic liposomes (CatL) and neutral liposomes (NeuL), as a vaccine carrier, the in vivo fate and immunogenicity of hepatitis B surface antigen (HBsAg), incorporated in CatL and NeuL, were investigated. CatL, composed of phosphatidyl choline (PC) and stearyl amine (SA) with a molar ratio of 9:1, showed a 2.5-fold higher incorporating efficiency of HBsAg than NeuL composed of PC alone. Most of HBsAg incorporated in both liposomes existed in an antibody-available form on the outer surface of liposomes. After intramuscular injection to rats, HBsAg in CatL resided at the injection site for a longer period than that in NeuL with terminal half lives of 52.5 and 42.9 h, respectively. However, HBsAg in NeuL was more efficiently taken up by the lymphatic organs and spleen than that in CatL. Furthermore, the group treated with HBsAg in NeuL showed earlier sero-conversion with higher anti-HBsAg titre than the group treated with HBsAg in CatL. Sero-conversion rates (SCRs) in both CatL- and NeuL-treated animals were 100% after every injection carried out, except the primary injection of CatL. These results demonstrate that CatL can enhance the retention of incorporated antigen at the injection site, compared with NeuL. However, the production of antibody by HBsAg in NeuL is more effective than that by HBsAg in CatL, probably due to the higher lymphatic targeting ability of NeuL. Thus, NeuL appears to be a better carrier for HBsAg than CatL.

Bone probing measurement as a reliable evaluation of the bone level in periodontal defects

BACKGROUND

Evaluation of periodontal regeneration is usually made by clinical measurements despite their limitations in determining the precise nature of the healing response. In the present study, the possibility of using bone probing measurements under local anesthesia to determine bone level changes without a re-entry procedure was investigated.

METHODS

Thirty-eight (38) first molars in 28 patients with chronic periodontitis who were scheduled to have periodontal surgery were included in this study. A custom-made acrylic resin stent was used for proper orientation of the probe for the bone probing depth measurement as well as probing depth measurements and surgical and radiographic bone level evaluations. The mesial, distal, and middle sites in the buccal aspect of each tooth were used. The sites were divided into 2 groups according to probing depth: those with a probing depth < 4 mm and those with a probing depth > or = 4 mm.

RESULTS

The probing depth was not significant in the difference between actual bone level (SBL) and bone probing depth (BP) (P >0.05). The greatest correlation to SBL was found with BP (gamma = 0.92), followed by radiographic bone level (RBL) (gamma = 0.69). The morphology of the defects had no significant effect on the difference between SBL and other measurements, while tooth surface and probing depth had significant effects on the difference between RBL and SBL.

CONCLUSIONS

The results of this study suggest that, regardless of probing depth, probing surface, and the presence of intrabony defects, there is a minimal difference between the BP and SBL. Determining the bone probing depth measurement is a kind of reliable method to estimate the regenerated bone level following periodontal treatment.

Primary small cell bronchogenic carcinoma in a 14-year-old boy

A 14-year-old Korean boy was admitted with cough, hemoptysis, and fever. A chest X-ray showed a solitary pulmonary mass and pneumonitis. Bronchial biopsy by fiberoptic bronchoscopy revealed a poorly differentiated small cell carcinoma. All of the staging information indicated that the patient had limited disease. During the 7 months following diagnosis, he received adjuvant chemotherapy in conjunction with radiotherapy. The size of the lesion was reduced by almost 50%. Small cell bronchogenic carcinoma has not been reported previously in childhood.

Molecular characterization of multidrug-resistant Streptococcus pneumoniae isolates in Korea. The Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study Group

Pulsed-field gel electrophoresis, ribotyping, and fingerprinting analysis of 22 invasive isolates of multidrug-resistant (MDR) pneumococci from Korea showed that 59 to 82% were genetically related. DNA sequencing of the PBP 2B gene showed relatively uniform alterations in nucleotides (5.4 to 7.8%) and amino acids (3.0 to 4. 3%), while Asn-276-->Lys, Arg-285-->Cys and Ser-305-->Phe substitutions were unique to Korean MDR strains, suggesting the spread of a few epidemic clones of resistant pneumococci within Korea.

Characterization of the pcbE gene encoding 2-hydroxypenta-2,4-dienoate hydratase in Pseudomonas sp. DJ-12

Nucleotide sequence extending 2,3-dihydroxybiphenyl 1,2-dioxygenase gene (pcbC) and 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase gene (pcbD) of Pseudomonas sp. DJ-12 was previously analyzed and the two genes were present in the order of pcbD-pcbC preceded by a promoter from Pseudomonas sp. DJ-12. In this study, a 3.8-kb nucleotide sequence located downstream of the pcbC gene was analyzed to have three open reading frames (ORFs) that are designated as orf1, pcbE and orf2 genes. All of the ORFs were preceded by each ribosome-binding sequence of 5-GGAXA-3 (X=G or A). However, no promoter-like sequence and transcription terminator sequence were found in the analyzed region, downstream of pcbC gene. Therefore, the gene cluster appeared to be present in the order of pcbD-pcbC-orf1-pcbE-orf2 as an operon, which is unique organization characterized so far in biphenyl- and PCB-degrading bacteria. The orf1 gene was composed of 1,224 base pairs which can encode a polypeptide of molecular weight 44,950 containing 405 amino acid residues. A deduced amino acid sequence of the orf1 gene product exhibited 21-33% identity with those of indole dioxygenase and phenol hydroxylase components. The pcbE gene was composed of 783 base pairs encoding 2-hydroxypenta-2,4-dienoate hydratase involved in the 4-chlorobiphenyl catabolism. The orf2 gene was composed of 1,017 base pairs encoding a polypeptide of molecular weight 37,378 containing 338 amino acid residues. A deduced amino acid sequence of the orf2 gene product exhibited 31% identity with that of a nitrilotriacetate monooxygenase component.

Cloning and characterization of the UDP-sugar hydrolase gene (ushA) of Enterobacter aerogenes IFO 12010

A bacterial alkaline phosphatase (BAP, the phoA gene product) is primarily responsible for the hydrolysis of the substrates 5-bromo-4-chloro-3-indolylphosphate-p-toluidine (XP) and p-nitrophenyl phosphate (pNPP). Using these substrates and an E. coli phoA mutant, we have cloned Enterobacter aerogenes genes conferring an XP(+) phenotype. Two types of clones were identified based on phenotypic tests and DNA sequences. One of them is a E. aerogenes phoA gene (XP(+), pNPP(+)) as expected; surprisingly the other one was found to be a ushA gene (XP(+), pNPP(-)), which encodes an UDP (uridine 5'-diphosphate)-sugar hydrolase. The E. aerogenes ushA gene shares high sequence identity with ushA of E. coli and the mutationally silent ushA0 gene of Salmonella typhimurium at both the nucleotide (over 79%) and amino acid (over 93%) levels. Expression of the E. aerogenes ushA gene in E. coli produced high level of UDP-sugar hydrolase, as confirmed by TLC (thin layer chromatography) analysis together with a presence of a strong band due to a XP hydrolysis on a polyacrylamide gel.

Late abnormal findings on high-resolution computed tomography after Mycoplasma pneumonia

BACKGROUND

The clinical course of Mycoplasma pneumonia is typically mild and self-limited. There are, however, several case reports of severe complication following this illness with considerable morbidity and mortality.

OBJECTIVES

This study was conducted to investigate, using high-resolution computed tomography (HRCT), the long-term pulmonary structural abnormalities after Mycoplasma pneumonia and to identify risk factors (chest radiograph findings, antibody titers, and host factors) that might increase the likelihood of developing the sequelae.

METHODS

Thirty-eight children requiring hospitalization attributable to Mycoplasma pneumonia were recruited by the retrospective examination of hospital records. They underwent HRCT after an interval of 1.0 to 2. 2 years. A control group of 17 children with the history of Mycoplasma upper respiratory infection was also studied after a similar interval.

RESULTS

Abnormal HRCT findings were present in 37% (14/38) of the pneumonia group, compared with 12% (2/17) of the control group. The abnormalities in the pneumonia group, which appeared alone or in combination, included mosaic perfusion (n = 12), bronchiectasis (n = 8), bronchial wall thickening (n = 4), decreased vascularity (n = 1), and air trapping on expiratory scan (9 of 29 tested). The area affected by these abnormalities, usually involving 2 or more lobes, corresponded in all cases to the location of the infiltrate on chest radiograph at the time of pneumonia. Between subjects with abnormal HRCT (n = 14) and normal HRCT (n = 24) in the pneumonia group, significant differences were observed in age at the time of pneumonia (mean +/- standard deviation: 5.3 +/- 2. 0 years vs 7.7 +/- 3.4 years) and peak antimycoplasma antibody titer (geometric mean [range of 1 standard deviation]; 1:7943 [3126-19 953] vs 1:3093 [832-11 482]).

CONCLUSIONS

We conclude that a considerable proportion of children with history of Mycoplasma pneumonia have abnormal findings on HRCT, suggestive of small airway obstruction and that younger age and higher antibody titer at the time of pneumonia may be risk factors for these sequelae.

Application of dry elixir system to oriental traditional medicine: taste masking of peonjahwan by coated dry elixir

Peonjahwan, an oriental traditional medicine composed of crude herbal drugs and animal tissues is bitter and poorly water-soluble. To mask the bitterness of peonjahwan and enhance the release of bilirubin, one of the crude active ingredients of peonjahwan, peonja dry elixir (PDE), was prepared using a spray-dryer after extracting the crude materials in ethanol-water solution. Coated peonja dry elixir (CPDE) was then prepared by coating the PDE with Eudragit acrylic resin. Panel assessed bitterness and release test of bilirubin from PDE and CPDE were carried out and compared with peonjahwan alone. PDE was found to have little effect upon the reduction of the bitterness of peonjahwan. However, the bitterness of CPDE was found to reduce to 1/4 of that of peonjahwan due to the encapsulation of crude active ingredients by the dextrin and Eudragit shell (P<0.05). The release rate of bilirubin from PDE and CPDE for 60 min increased about 3.5- and 2.5- fold, respectively, compared to peonjahwan at pH 1.2. It is concluded that CPDE, which masked the bitterness of peonjahwan and enhanced the release of bilirubin, is a preferable delivery system for peonjahwan.

The effect of regular salbutamol on lung function and bronchial responsiveness in patients with primary ciliary dyskinesia

STUDY OBJECTIVE

There is growing evidence that regular beta(2)-agonist use in patients with asthma is associated with decreased airway caliber and increased bronchial responsiveness. The aim of this study was to determine whether regular treatment with beta(2)-agonists induces changes in lung function and bronchial responsiveness in patients with primary ciliary dyskinesia.

DESIGN

A randomized, double-blind, placebo-controlled, crossover study.

PATIENTS

Nineteen children with primary ciliary dyskinesia.

INTERVENTIONS

Subjects received inhaled salbutamol or identical placebo (2 x 100 microg qid) for periods of 6 weeks with a wash-out period of 4 weeks.

MEASUREMENTS AND RESULTS

FEV(1) was measured before and 3 weeks and 6 weeks after salbutamol or placebo treatment. High-dose methacholine inhalation tests were performed before and 6 weeks after each treatment. The provocative concentration of methacholine producing a 20% fall in FEV(1) (PC(20)) and maximal airway narrowing (MDeltaFFEV(1)) was measured. No significant change in FEV(1) was observed during the salbutamol or placebo periods. No significant differences in the parameters of bronchial responsiveness (PC(20) and MDeltaFFEV(1)) were noted as the result of either salbutamol or placebo treatment.

CONCLUSION

Our data have shown that salbutamol, inhaled regularly for 6 weeks, did not cause either a decline in lung function or an increase in bronchial responsiveness in subjects with primary ciliary dyskinesia.

Salivary gland tumors: evaluation with two-phase helical CT

PURPOSE

To evaluate two-phase helical computed tomography (CT) in the characterization of salivary gland tumors.

MATERIALS AND METHODS

Sixty-four patients with major salivary gland tumors underwent two-phase helical CT. The histopathologic diagnosis was obtained by means of surgical resection or biopsy in all patients. After the injection of 90 mL of contrast material at a rate of 3 mL/sec, helical CT scans were obtained at early and delayed phases with scanning delays of 30 and 120 seconds, respectively. The attenuation change and enhancement patterns in the tumors were assessed. The attenuation change in the tumor also was assessed quantitatively as the ratio of the CT number (in Hounsfield units) at delayed phase scanning to that at early phase scanning.

RESULTS

There were 35 pleomorphic adenomas, nine Warthin tumors, and 20 malignant tumors. Two-phase helical CT showed increase in attenuation in 30 (86%) pleomorphic adenomas, decrease in eight (89%) Warthin tumors, and increase in 11 (55%) and no change in eight (40%) malignant tumors at delayed phase scanning. A multinodular enhancement pattern was found in only 12 (34%) pleomorphic adenomas. The ratio of CT numbers was significantly different between Warthin tumors and pleomorphic adenomas and between Warthin tumors and malignant tumors.

CONCLUSION

The analysis of enhancement patterns by using two-phase helical CT will be helpful in the differential diagnosis of salivary gland tumors.

Pharmacokinetics and organ distribution of cyclosporin A incorporated in liposomes and mixed micelles

The commercially available intravenous dosage form of cyclosporin A (C-CsA) contains a solubilizing agent, polyoxyethylated castor oil, which has been reported to be toxic. To replace the toxic solubilizing agent present in C-CsA, liposomal and mixed micellar preparations were made to solubilize CsA by the proliposome method and characterized. Furthermore, pharmacokinetics and organ distributions of these preparations were evaluated in comparison to C-CsA, which is micellar. The mean size of liposomal preparation (L-CsA) composed of DPPC/PA (molar ratio 3/1) and CsA was 43.6 nm and that of mixed micellar preparation (M-CsA) composed of DMPC/DSPE-PEG (molar ratio 95/5) and CsA was 6.5 nm. The solubilization of CsA was 2-fold greater in mixed micellar solution than in liposomes (0.06 vs 0.03 mg of CsA/mg of lipid). L-CsA, M-CsA and C-CsA were intravenously administered into rats via the femoral vein to analyze pharmacokinetics and organ distribution of CsA. M-CsA was not significantly different from C-CsA in every pharmacokinetic parameter studied. However, L-CsA resulted in 30% decrease in AUC and 55% increase in Cl(t) compared with C-CsA (P<0. 05), without any significant differences in MRT, V(dss) and t(1/2). In addition, the distributions of M-CsA and L-CsA in different organs were not significantly different from those of C-CsA (0.05), except for a 51% decrease of M-CsA in the spleen at 4 h and a 33% increase of L-CsA in the liver at 4 h (P<0.05). These findings demonstrate that the liposomal preparation composed of DPPC/PA and CsA shows slightly different pharmacokinetics and organ distribution patterns from C-CsA, whereas the mixed micellar preparation composed of DMPC/DSPE-PEG and CsA exhibits similar patterns to C-CsA, as expected. Furthermore, these results suggest that those mixed micellar and liposomal preparations can replace C-CsA containing the toxic solubilizing agent, thus providing useful alternative dosage forms for intravenous administration of CsA.

Lad, an adapter protein interacting with the SH2 domain of p56lck, is required for T cell activation

T cell-specific Src family tyrosine kinase, p56lck, plays crucial roles in T cell differentiation, activation, and proliferation. These multiple functions of p56lck are believed to be conducted through the protein-protein interactions with various cellular signaling proteins. To clarify the mechanisms through which p56lck contributes to T cell signaling, we identified the proteins binding to the Src homology 2 (SH2) domain of p56lck through a tyrosine phosphorylation-dependent yeast two-hybrid screening. Subsequent characterization of positive clones revealed the presence of a protein of 366 aa named Lad (Lck-associated adapter protein), which is a potential murine homologue of previously reported TSAd, a T cell-specific adapter protein. Lad contains several protein-protein interaction domains including a zinc-finger motif, an SH2 domain, a proline-rich SH3 binding motif, and several phosphotyrosine sites. Furthermore, Lad was tyrosine phosphorylated and associated with p56lck in vivo and redistributed from cytoplasm to the plasma membrane in a T cell activation-dependent manner. Moreover in T cells, IL-2 promoter activity was enhanced upon coexpression of Lad but was inhibited by the coexpression of antisense Lad RNA. These characteristics of Lad suggest that Lad play an essential role as an adapter protein in p56lck-mediated T cell signaling.

Administration-time differences in the pharmacokinetics of gentamicin intravenously delivered to human beings

Administration-time differences of gentamicin pharmacokinetics were studied by crossover design after a single intravenous administration of gentamicin (80 mg) to 10 human subjects at 09:00 (morning time) and 22:00 (nighttime). The profiles of serum gentamicin concentration showed a significant statistical difference between 09:00 and 22:00, suggesting circadian variations of pharmacokinetic behaviors. A significant circadian rhythm of pharmacokinetic parameters as a function of time of day was noted in human subjects, showing lower total body clearance Clt and higher serum area under the curve (AUC) when given at nighttime. The half-life t1/2 was shorter in the morning (2.82 h +/- 0.43 h) when compared to the nighttime (2.97 h +/- 0.36 h), but the difference was not statistically significant. The AUC was significantly greater in the morning (23.4 +/- 3.84 micrograms-h/mL) than that in the nighttime (26.3 +/- 5.79 micrograms-h/mL) (p < .05), most likely because the Clt was significantly higher when gentamicin was given in the morning (3.51 +/- 0.57 L/h) versus in the nighttime (3.18 +/- 0.65 L/h). Although the volume of distribution Vd decreased when given at nighttime, it was independent of the dosing time. From this study, there was an administration-time difference of gentamicin pharmacokinetics in human beings. The optimized dosing regimen of gentamicin can be decided by considering circadian rhythm and rest-activity routine so that minimized toxicity and effective therapy are established for patients. The current findings also can be applied to other drugs with circadian rhythms of pharmacokinetics and narrow therapeutic windows in clinical chronotherapeutics.

Enhanced hepatocyte uptake and liver targeting of methotrexate using galactosylated albumin as a carrier

Liver targeting of drugs has wide therapeutic implications due to numerous liver-related diseases. Using conjugates of methotrexate (MTX) to variously galactosylated bovine serum albumin (BSA), we studied whether we could enhance the liver targeting of MTX, a model drug, via galactose receptors selectively abundant on the hepatocytes. Here, we report that the galactosylation of the carrier protein BSA significantly enhanced the hepatocyte uptake and liver targetability of MTX. In vitro, the amount of MTX taken up by rat hepatocytes was positively correlated with the galactose content in BSA. MTX conjugates were relatively stable in plasma, but released MTX with time in liver homogenates. These results imply that the conjugates would exert low toxicity in the blood, but have therapeutic activity in the liver by liberating MTX. In vivo, MTX-galactosylated BSA conjugates (MTX-L(24)BSA) showed significantly different pharmacokinetics from free MTX or MTX-BSA conjugates. The plasma level of free MTX rapidly declined in a biexponential fashion with an apparent terminal half-life of 0.35 h. MTX-BSA conjugates showed the slowest decline with an apparent terminal half-life of 6 h, whereas MTX-L(24)BSA showed a biphasic pattern; a rapid distributive phase with a half-life of 0.567 h and a slow terminal phase. MTX-L(24)BSA showed the highest liver targetability, when evaluated in terms of two indices based on the area under the total amount of radioactivity-time curve (AUQ); Te*(liver), % AUQ(liver) to total AUQ, and te*, the ratio of AUQ(liver) to AUQ(kidney). Compared with free MTX and MTX-BSA, MTX-L(24)BSA showed about twofold higher Te*(liver) of 87.5%. The te* of MTX-L(24)BSA was 25- and fourfold higher than those of free MTX and MTX-BSA, respectively. Moreover, MTX-L(24)BSA showed a gradual increase in the therapeutically active intact form of MTX in the liver while showing the lowest level of intact MTX in the kidney. These results suggest that galactosylated BSA has a great potential as an hepatocyte-directed and more effective liver targeting carrier of drugs for liver diseases.