[S antigen in retinas of royal college of surgeons rats: time course and retinal pigment epithelium transplant study]

Retinas of Royal College of Surgeons (RCS) rats were investigated immunocytochemically for the distribution of S antigen prior to and during the retinal disease process. RCS retinas onto which retinal pigment epithelium (RPE) had been transplanted were also immunostained with antibody for S antigen. At P2, weak immunostaining for S antigen was seen in neuroepithelium. At P22, the staining pattern outlined the entire photoreceptor layer. At P30, at the beginning of retinal degeneration, immunostaining for S antigen was considerably reduced in the degenerating photoreceptor outer segment. In the RCS retina at P90, immunostaining for S antigen was completely lost. However, retinas with transplanted RPE showed preserved immunocytochemical staining for S antigen at this late stage. These results suggest a loss of production of S antigen in degenerated retinal tissue, and that RPE transplantation helps to preserve S antigen in the RCS rat retina.

[Evaluation of bactericidal activity of arbekacin in mixed culture with MRSA and Pseudomonas aeruginosa using an in vitro pharmacokinetic simulation system]

The bactericidal activities of arbekacin (ABK), vancomycin (VCM), gentamicin (GM) and netilmicin (NTL) in mixed culture with Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa were examined using an in vitro computer programmed pharmacokinetic simulation system and also the protective effect of these agents on systemic infection in neutropenic mice was examined. In a mixed culture of S. aureus No. 235 (MRSA) and P. aeruginosa E7, ABK showed a strong bactericidal activity and an inhibition of regrowth against both bacteria, and GM and NTL showed similar effects. On the other hand, VCM showed a bactericidal activity against S. aureus No. 235, but not against P. aeruginosa. In the protective study, ABK was evidently more effective than GM, NTL or VCM against a systemic mixed infection of mice with S. aureus No. 235 and P. aeruginosa E7. In brief, the ED50 values of ABK, VCM, GM and NTL were 19.5, > 100, 40.5 and 45.2 mg/kg, respectively.

Neurotrophin-3 gene polymorphism associated with schizophrenia

The recent possible neurodevelopmental etiology of schizophrenia makes the neurotrophin-3 (NT-3) gene an interesting candidate locus. We studied the allelic distributions of dinucleotide repeat polymorphism at the NT-3 gene locus in 70 patients with schizophrenia and in 70 controls. A highly significant difference between the two groups was observed at the allele A3. Even Bonferroni's correction was used, the difference was still significant. Individuals with homozygous or heterozygous for the allele A3 had a 2.4-fold increased risk of schizophrenia. Determination of NT-3 genotype may help to identify those at greater risk of schizophrenia. Furthermore, this finding supports evidence implicating neurodevelopmental deficit in the pathogenesis of this disorder.

KF17837 ((E)-8-(3,4-dimethoxystyryl)-1,3-dipropyl-7-methylxanthine), a potent and selective adenosine A2 receptor antagonist

8-(3,4-Dimethoxystryryl)-1,3-dipropyl-7-methylxanthine exhibited high affinity and selectivity for adenosine A2A receptors in binding assay using rat striatal A2A receptors labeled with [3H]2-[p-(2-carboxyethyl)-phenethylamino]-5'-N-ethylcarboxamido adenosin e (CGS21680). The affinity was stereo selective: the E isomer, KF17837, showed a Ki value of 1.0 +/- 0.057 nM for the A2A receptors, whereas the Z isomer showed much lower affinity. KF17837 had 62-fold selectivity for the A2A receptors versus rat forebrain A1 receptors labeled with [3H]N6-cyclohexyladenosine (CHA). KF17837 was rapidly photoisomerized to form a stable equilibrium mixture (18% E - 82% Z), KF17837S, which showed Ki values of 7.9 +/- 0.055 nM and 390 +/- 68 nM for the A2A and A1 receptors, respectively. The inhibition type was competitive for [3H]CGS21680 binding. In rat pheochromocytoma PC12 cells KF17837S antagonized cAMP accumulation induced by 1 microM CGS21680 via the A2A receptors, with an IC50 value of 53 +/- 10 nM. cAMP accumulation induced by 10 microM 5'-N-ethylcarboxamidoadenosine via the A2B receptors in Jurkat cells (human T-cell line) was inhibited by KF17837S with an IC50 value of 1500 +/- 290 nM. These results indicate that KF17837S (and hence KF17837) is a highly potent and selective adenosine A2A receptor antagonist.

In vitro and in vivo antibacterial activities of KRM-1648 and KRM-1657, new rifamycin derivatives

The in vitro and in vivo antibacterial activities of the new rifamycin derivatives KRM-1648 and KRM-1657 were compared with those of rifampin. Rifabutin, ciprofloxacin, and clarithromycin were also tested for reference. The respective MICs of KRM-1648 and KRM-1657 for 90% of the strains tested (MIC90S) were 0.016 and 0.0078 microgram/ml, respectively, for methicillin-susceptible Staphylococcus aureus, 0.016 and 0.0039 microgram/ml, respectively, for methicillin-resistant S. aureus, and 0.0625 and 0.016 microgram/ml, respectively, for methicillin- and quinolone-resistant S. aureus. These MIC90S of KRM-1657 were equal to or 2- to 64-fold lower than those of rifampin. KRM-1648 and KRM-1657 with MIC90S of between 0.002 and 0.078 microgram/ml were 2- to 128-fold more active than rifampin against Staphylococcus epidermidis and Streptococcus species, including Streptococcus pneumoniae and Streptococcus pyogenes. The MIC90S of KRM-1657 for Haemophilus influenzae and Neisseria gonorrhoeae were 0.25 and 0.1 microgram/ml, respectively; KRM-1657 was almost as active as rifampin and was 8- to 16-fold more active than KRM-1648 against these strains. The frequency of occurrence of spontaneous mutations to resistance to KRM-1648 and KRM-1657 was equal to that to rifampin. Against systemic infection with S. aureus in mice, the efficacies of KRM-1648 and KRM-1657 were comparable to that of rifampin.

A modified nonradioactive method for northern blot analysis

In this report we use several previously described methods, in novel combination, to establish a sensitive and flexible nonradioactive method. First, we prepared single-stranded digoxigenin-labeled probes using a high-efficiency polymerase chain reaction (PCR) method (4). For detection of RNA, blots were hybridized with probes containing digoxigenin and then incubated with alkaline phosphatase-conjugated anti-digoxigenin antibody. Bound probe was rapidly detected with X-ray film using localized light emission from the reaction of alkaline phosphatase with lumigen-paraphenylenediamine substrate (5). This method allows flexibility in probe sequence selection, independent of restriction enzyme site location, and it works well with small probes. This approach allows sensitive differential analysis of closely related members of a gene family.

Conformational stability of alpha-lactalbumin missing a peptide bond between Asp66 and Pro67

The peptide bond between Asp66-Pro67 of alpha-lactalbumin was cleaved with formic acid (cleaved alpha-lactalbumin). Secondary structural changes of the cleaved alpha-lactalbumin, in which the two separated polypeptides were joined by disulfide bridges, were examined in solutions of sodium dodecyl sulfate (SDS), urea, and guanidine hydrochloride. The structural changes of the cleaved alpha-lactalbumin were compared with those of the intact protein. The relative proportions of secondary structures were determined by curve fitting of the circular dichroism. The cleaved alpha-lactalbumin contained 29% alpha-helical structure as against 34% for the intact protein. Some helices of the cleaved alpha-lactalbumin which had been disrupted by the cleavage appeared to be reformed upon the addition of SDS of very low concentration (0.5 mM). In the SDS solution, the helicities of both the intact and cleaved proteins increased, attaining 44% at 4 mM SDS. On the other hand, the helical structures of the cleaved alpha-lactalbumin began to be disrupted at low concentrations of guanidine hydrochloride and urea compared with that of the intact protein. However, no difference was observed in the thermal denaturations of the intact and cleaved proteins, except for the difference in the original helicities. The helicities of both proteins decreased with an increase of temperature up to 65 degrees C and recovered upon cooling.

Adaptation of hepatitis C virus for persistent infection in patients with acute hepatitis

Nucleotide sequencing was used to analyze amino acid substitutions in the putative envelope 1 (E1) and envelope 2/nonstructural 1 (E2/NS1) regions of hepatitis C virus (HCV) to clarify a viral mechanism of persistent infection in three patients with acute hepatitis C who developed chronic hepatitis and two patients with chronic hepatitis. The HCV RNA titer in serum decreased markedly after the onset of acute hepatitis and then re-elevated. During this period, the substitution rate in the E2/NS1 region (especially in the hypervariable region located in the N-terminus) was significantly higher in patients with acute hepatitis than in patients with chronic hepatitis (P < 0.05). When patients with acute hepatitis C became persistent HCV carriers, the substitution rate decreased to the level seen in patients with chronic hepatitis. The amino acid substitution rate in the E1 region in the acute phase was similar to that found in the chronic HCV carrier state. These observations suggest that rapid substitution of the amino acid sequence in the hypervariable region of the E2/NS1 region may be one of the mechanisms of persistent HCV infection.

[Diagnostic value of glass microfibre-based basophil histamine release test in food allergic children. Comparison with specific IgE antibody and skin scratch test]

We evaluated the diagnostic value of the glass microfibre-based histamine release test (HRT), which allows measurements to be performed using small amounts of whole blood, in 50 children with food allergy case histories. The patients were evaluated by radioallergosorbent tests (RAST), skin scratch tests (ST) and food challenge tests. Of the 50 patients, 39 had a confirmed clinical diagnosis of food allergy from food challenge tests and case histories, and were affected by a total of 60 positive allergens (egg 37, milk 11, soy beans 4, wheat 5, rice 3). The concordance, sensitivity, and specificity of HRT with the clinical diagnosis were 85.3%, 66.7% and 92.1%, those of RAST were 59.4%, 90.0% and 48.2%, and those of ST were 84.7%, 71.8% and 88.7%, respectively. The positive predictive values of HRT, RAST and ST were 75.5%, 38.8% and 66.7%. The false positive ratio of HRT (24.5%) was the lowest among all the tests. There was a significant correlation between HRT and RAST (r = 0.513, p < 0.001). However, the concordance of HRT with respect to RAST was 56.0%. The concordance and specificity of HRT in relation to the clinical diagnosis were higher than RAST and the same as ST. The sensitivity of RAST was higher than that of HRT. From these results, we concluded that RAST is good for the screening of allergens and that HRT is a useful diagnostic method for the confirmation of a clinical allergy.

The yeast MOT2 gene encodes a putative zinc finger protein that serves as a global negative regulator affecting expression of several categories of genes, including mating-pheromone-responsive genes

The STE4 gene encodes the beta subunit of a heterotrimeric G protein that is an essential component of the pheromone signal transduction pathway. To identify downstream component(s) of Ste4, we sought pseudo-revertants that restored mating competence to ste4 mutants. The suppressor mot2 was isolated as a recessive mutation that restored conjugational competence to a temperature-sensitive ste4 mutant and simultaneously conferred a temperature-sensitive growth phenotype. The MOT2 gene encodes a putative zinc finger protein, the deletion of which resulted in temperature-sensitive growth, increased expression of FUS1 in the absence of pheromones, and suppression of a deletion of the alpha-factor receptor. On the other hand, sterility resulting from deletion of STE4 was not suppressed by the mot2 deletion. These phenotypes are similar to those associated with temperature-sensitive mutations in CDC36 and CDC39, which are proposed to encode general negative regulators of transcription rather than factors involved in the pheromone response pathway. Deletion of MOT2 also caused increased transcription of unrelated genes such as GAL7 and PHO84. Overexpression of MOT2 suppresses the growth defect of temperature-sensitive mutations in CDC36 and CDC39. These observations suggest that Mot2 functions as a general negative regulator of transcription in the same processes as Cdc36 and Cdc39.

Simultaneous multielemental analysis of daily food samples by inductively coupled plasma mass spectrometry

Several toxic elements in total composite food samples of hospital diets were determined simultaneously by inductively coupled plasma mass spectrometry (ICP-MS). Trace element concentrations of Be, Cr, As, Cd, Sn, Sb, Ce, Hg and Pb changed widely ranging from a few ng.g-1 to less than 3 micrograms.g-1 in all 24 samples collected through a year. Be, Sn, and Hg were not detected in rice sample alone, and other trace elements, with the exception of Cr and As, were less than approximately 50% levels, as compared with mixed diet samples. The daily intakes of these toxic elements were in the ranges of a few to several hundreds of micrograms.

Pro-gastrin-releasing peptide(31-98) is a specific tumor marker in patients with small cell lung carcinoma

Gastrin-releasing peptide (GRP) is a specific and an actively secreted product of small cell lung carcinoma (SCLC) cells. Based on this observation, we attempted to develop a new approach for early detection of SCLC and for monitoring therapeutic response in SCLC patients. Recombinant human ProGRP(31-98), a region common to three types of human ProGRP molecules, was synthesized, and a convenient radioimmunoassay system was developed; in this assay, the minimum detectable amount in serum was 10 pM when 0.1 ml of unextracted serum was used. Serum levels of immunoreactive ProGRP(31-98) were measured in 247 normal subjects, 180 patients with nonmalignant pulmonary diseases, 231 patients with non-SCLC, and 140 patients with SCLC. The percentages of subjects with the level greater than 10 pM in normal subjects and patients with nonmalignant pulmonary diseases and with non-SCLC were 1.2, 2.2, and 3.0%, respectively. In contrast, 76% of patients with SCLC had elevated levels; the positive rates in SCLC patients with limited and extensive diseases were 73 and 79%, respectively, indicating that the serum Pro-GRP(31-98) level could serve as a reliable tumor marker in SCLC patients, even at a relatively early stage of this disease. Moreover, changes in the serum ProGRP(31-98) showed excellent correlation with the therapeutic responses in SCLC patients. These results indicate that the determination of serum ProGRP(31-98) levels plays an important role in the diagnosis and treatment of SCLC patients.

[Computed tomography findings of malignant pleural mesothelioma]

Computed tomography (CT) findings were assessed in 7 patients with malignant mesothelioma. CT findings were also reviewed in 9 patients with lung cancer and pleuritis carcinomatosa and in 11 patients with tuberculous pleuritis. Five patients with malignant mesothelioma underwent CT scans twice, on admission and from 1 to 7 months after admission. Tuberculous pleuritis could be distinguished from pleuritis carcinomatosa and malignant mesothelioma by the presence or absence of pleural nodularity and chest wall invasion. Although it was difficult to identify specific CT features clearly distinguishing malignant mesothelioma from pleuritis carcinomatosa, characteristic findings of malignant mesothelioma appeared to include the rapid development and progression of pleural rind and a tendency to spread directly into the chest wall. We divided the pleura into the four regions; upper anterior, upper posterior, lower anterior and lower posterior regions. Pleural changes were more frequently seen in the lower pleural regions than in the upper pleural regions, in malignant mesothelioma.

Aspartate aminotransferase-linked immunoglobulin complexes in serum of a patient with primary biliary cirrhosis

A 51-year-old woman who had been treated for primary biliary cirrhosis (PBC) was admitted to our hospital for evaluation of unexplained, isolated, persistently increased aspartate aminotransferase (AST) activity. Results of laboratory tests on admission showed: AST 171 KU, alanine aminotransferase 28 KU, and anti-mitochondrial titer 1/1280. Results of hepatitis B surface antigen (HBs Ag) and hepatitis C virus antibody (HCV Ab; C100-3) assays were negative. Histology of a liver biopsy specimen was compatible with a diagnosis of PBC (stage III of Scheuer's classification). The molecular size of serum AST was estimated to be more than 500,000 by high-performance size-exclusion liquid chromatography. Electrophoretic analysis showed an abnormal band of AST between supernatant AST (sAST) and mitochondrial AST (mAST), which band was characteristic of AST-immunoglobulin complexes (AST-Ig). Ouchterlony double-diffusion and immunoprecipitation tests identified the immunoglobulin component as IgM. The presence of AST-Ig appeared to be responsible for the elevated serum AST.

Human T-lymphotropic virus type I uveitis

In addition to adult T-cell leukemia (ATL) and chronic myelopathy (HAM/TSP), our current study indicates that human T lymphotropic virus type I (HTLV-I) is a causative agent for a specific type of uveitis with unknown etiology (idiopathic uveitis). The present paper describes the seroepidemiological, clinical, and molecular biological evidences that indicate uveitis seen in HTLV-I asymptomatic carriers (HTLV-I uveitis) is a distinct clinical entity. In an HTLV-I endemic area in Japan, the seroprevalence of HTLV-I in idiopathic uveitis was 38%, while those in uveitis with defined etiology and in non-uveitic ocular diseases were 10% and 19%, respectively. Strikingly, the HTLV-I seroprevalence in younger aged patients (20-49 years) with idiopathic uveitis was 49%, while only 8% in the control group (P < 0.001). A very similar observation was recorded even in HTLV-I less endemic area, suggesting that HTLV-I infection plays a role as a risk factor for idiopathic uveitis. Clinical analysis revealed that an intermediate uveitis characterized by moderate opacities in the vitreous body and retinal vasculitis was seen in the majority the patients. The proviral DNA of HTLV-I was detected from inflammatory cells in the eye of all tested patients using PCR technique. These data thus indicate that HTLV-I is closely related to a certain type of uveitis and the uveitis (HTLV-I uveitis) is a distinct clinical entity.

Interleukin-1 beta production in the rabbit brain during endotoxin-induced fever

Interleukin-1 beta (IL-1 beta) production in the brain and the spleen was investigated in rabbits made febrile by intravenous (I.V.) injection of endotoxin, or human recombinant IL-1 beta (hIL-1 beta). The endotoxin used in the present study was the lipopolysaccharide (LPS) of Salmonella typhosa endotoxin. Monophasic fever was induced by I.V. injection of a low dose of LPS (0.02 micrograms kg-1) and biphasic fever by I.V. injection of a large dose of LPS (4 micrograms kg-1), a sublethal dose of LPS (40 micrograms kg-1) or hIL-1 beta (2 micrograms kg-1). In situ hybridization and immunohistochemical studies revealed that, although no IL-1 beta production was observed in the brain at 1 and 3 h after injection of a low dose of LPS (0.02 micrograms kg-1) or of hIL-1 beta (2 micrograms kg-1), IL-1 beta production was demonstrated in organum vasculosum laminae terminalis (OVLT) and some cells around the blood vessels in the parenchyma 1 h after 4 micrograms kg-1 LPS. IL-1 beta production was detected throughout the brain after 40 micrograms kg-1 LPS. Pretreatment with indomethacin, an inhibitor of prostaglandin synthesis, did not affect IL-1 beta production in the brain induced by 4 micrograms kg-1 LPS. The cell type which produces IL-1 beta in the OVLT following LPS injection was confirmed to be a macrophage by electron microscopy. The cells producing IL-1 beta in the parenchyma were determined to be microglial cells. In the spleen, each dose of LPS induced a significant increase in IL-1 beta production in polymorphonuclear cells and macrophages in the red pulp 1 h after injection. However, 2 micrograms kg-1 hIL-1 beta did not induce IL-1 beta production in the spleen. The present results show clearly that systemic administration of LPS induces IL-1 beta production in the OVLT which may be responsible for induction of the second phase of biphasic fever. The production of IL-1 beta in the OVLT was not attributable to the action of peripherally synthesized IL-1 beta or prostaglandins.

Detection of antibody-coated bacteria in expectorated sputum for diagnosis of lower respiratory infections

We evaluated antibody-coated bacteria (ACB) in expectorated sputum to discriminate contaminating or colonizing organisms from true pathogens. We examined 60 expectorated sputum samples from 51 patients with lower respiratory infections (chronic obstructive pulmonary disease 25, pneumonia 20, purulent tracheobronchitis 6). All samples were examined with quantitative culture and immunofluorescent demonstration of ACB. From the results of quantitative culture, we divided specimens into pathogen-isolated and pathogen-free samples. Among pathogen-isolated samples, in which we isolated accepted pathogenic organisms at > or = 10(7) colony-forming units per ml, 16 of 23 samples were ACB-positive (69.5%). In contrast, among pathogen-free samples, in which we isolated accepted pathogens at < 10(7) colony forming units per ml or only upper respiratory flora, only 3 of 37 samples were ACB-positive (8.1%). The ACB-positive rate was significantly higher in pathogen-isolated than in pathogen-free samples (P < 0.001). Consequently, detecting ACB in expectorated sputum shows good potential as another criterion for distinguishing contaminating or colonizing organisms from true pathogens.

[Effects of vasoactive cyclooxygenase products on shunt flow and extravascular lung water in acute lung injuries]

Using 50 mongrel dogs with alveolar flooding produced by oleic acid administration, the possible roles of vasoactive cyclooxygenase products on intrapulmonary shunt flow (QS/QT) and extravascular lung water (ETVI) in acutely injured lungs were assessed. Suppressing cyclooxygenase activity with indomethacin administration diminished the concentrations of thromboxane (TX) B2 and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) in arterial blood, resulting in a significant reduction in QS/QT. Furthermore, indomethacin completely suppressed the increase in ETVI. Inhibition of TXA2 generation by OKY-046 (thromboxane A2 synthase blocker) diminished the concentration of TXB2 while increasing that of 6-keto-PGF1 alpha in blood. Administration of either OKY-046 or synthetic prostacyclin (PGI2) markedly enhanced QS/QT, in association with an increase in ETVI. In conclusion, the potent vasodilator prostacyclin was considered to enhance shunt flow, leading to the augmentation of edema formation.

Adenosquamous carcinoma of the gallbladder: a clinicopathological, immunohistochemical and flow-cytometric study of twenty cases

Twenty patients (7.4%) with adenosquamous carcinoma of the gallbladder were selected from 271 surgically resected gallbladder cancers. The 20 patients were composed of 8 men and 12 women with a mean age of 66.9 years. Histologically, all twenty tumors showed an abrupt transition between the adenocarcinoma (AC) and squamous cell carcinoma (SCC) areas, and well differentiated AC was also found in the peripheral area of the tumor. A histochemical and immunohistochemical study using alcian blue, periodic acid-Schiff, cytokeratins, involculin and tissue polypeptide antigen disclosed a different nature of the two components. DNA heterogeneity between the components was detected in 5 of 7 cases by flow cytometry. The positive rate of immunostaining for proliferating cell nuclear antigen in the SCC areas (mean 20.55%) was larger than that of the AC areas (mean 11.40%) (P = 0.0029), which indicated that the SCC areas had a greater proliferative capacity than AC areas. These results suggest that the SCC component of adenosquamous carcinoma of the gallbladder arose by a stepwise molecular progression of the pre-existing AC. Furthermore, the prognosis of adenosquamous carcinomas of the gallbladder (mean survival: 10 months) in the advanced stage (pTNM 2-4) was less favorable than those of papillary and well differentiated AC (mean survival: 99 months and 86 months) (P < 0.0001).

Toxic epidermal necrolysis with tracheobronchial and pulmonary complications

A 55-year-old man developed multiple erythematous skin lesions after surgery for acoustic neurinoma. Necrosis and detachment of the epidermis developed and a diagnosis of toxic epidermal necrolysis (TEN) was made. Progressive dyspnea was evident two days after the onset of the skin lesions. Chest X-ray revealed diffuse interstitial shadows in both lung fields. On bronchoscopic examination, erosion, vesicle formation, necrosis and desquamation of the epidermis were seen in the tracheobronchial mucosa. Therapy, including prednisolone, improved the skin lesions as well as the chest X-ray and bronchoscopic findings. Tracheobronchial and pulmonary lesions were followed before, during and after treatment of TEN.

Thyroid gland metastasis from renal cell carcinoma masquerading as nodular goitre

Renal cell carcinoma metastasizing to the thyroid gland, in a 72 year old Japanese woman, is reported. The patient had undergone a left radical nephrectomy for renal cell carcinoma 3 months prior to the present operation. The patient noticed a nodular goitre but there was no evidence of any systemic spread of renal cell carcinoma. The histopathologic diagnosis, from a left lobectomy of the thyroid gland, was thyroid gland metastasis from renal cell carcinoma in adenomatous goitre. Clinical manifestation of thyroid gland metastasis from renal cell carcinoma, with no evidence of systemic involvement, is seen rarely. A case is reported and the condition discussed briefly.