Prescribing Pattern of Antidepressants in Children and Adolescents: Findings from the Research on Asia Psychotropic Prescription Pattern

OBJECTIVE

Pharmacotherapy of depression in children and adolescents is complex. In the absence of research into the efficacy and safety of antidepressants in this group of patients, their off-label prescription is common. This paper aimed to illustrate the prescription pattern of antidepressants in children and adolescents from major psychiatric centres in Asia.

METHODS

The Research on Asia Psychotropic Prescription Pattern on Antidepressants worked collaboratively in 2013 to study the prescription pattern of antidepressants in Asia using a unified research protocol and questionnaire. Forty psychiatric centres from 10 Asian countries / regions participated and 2321 antidepressant prescriptions were analysed.

RESULTS

A total of 4.7% antidepressant prescriptions were for children and adolescents. Fluoxetine, sertraline, and escitalopram were the most common antidepressants prescribed for children and adolescents. Almost one-third (30.3%) of prescriptions were for diagnoses other than depressive and anxiety disorders. There was less antidepressant polypharmacy and concomitant use of benzodiazepine, but more concomitant use of antipsychotics in children and adolescents compared with adults.

CONCLUSION

Off-label use of antidepressants in children and adolescents was reported by 40 Asian psychiatric institutions that participated in the study. In-service education and regulatory mechanisms should be reinforced to ensure efficacy and safety of antidepressants in children and adolescents.

Antidepressant Prescription Pattern in the Presence of Medical Co-morbidity: REAP-AD 2013 Study

OBJECTIVE

To evaluate the prescription pattern of antidepressants in patients with medical co-morbidity from major psychiatric centres in Asia.

METHODS

The Research on Asian Psychotropic Prescription Pattern for Antidepressants (REAP-AD 2013) collected data from 42 psychiatric centres in 10 Asian countries and regions. Antidepressant prescriptions of 2320 patients with various psychiatric disorders were evaluated. Of these, 370 patients who had specified medical co-morbidities formed the study cohort.

RESULTS

Escitalopram (20%) and mirtazapine (20%) were the most commonly prescribed antidepressants in patients with medical co-morbidity followed by sertraline (16%), trazodone (15%), and paroxetine (12%). Overall, more than half (52%; 247/476) of prescriptions comprised selective serotonin reuptake inhibitors. Slightly less than two-thirds (63%; n = 233) of patients received at least 1 selective serotonin reuptake inhibitor. In addition, 79% of patients were prescribed only 1 antidepressant. The mean number of antidepressants used per patient was 1.25 (standard deviation, 0.56). There were subtle differences in the most preferred antidepressant across medical illnesses such as diabetes mellitus, liver dysfunction, acid peptic disease, and cerebrovascular disease. Differences were also seen in prescription patterns across different countries.

CONCLUSION

Although selective serotonin reuptake inhibitors formed the bulk of antidepressant prescriptions in the presence of medical co-morbidity, mirtazapine was also commonly used in the presence of medical co-morbidities. Specified medical morbidities do influence the selection of antidepressants.

Transforming growth factor-β stimulates the expression of eotaxin/CC chemokine ligand 11 and its promoter activity through binding site for nuclear factor-κβ in airway smooth muscle cells

BACKGROUND

Chemokines ligands of CCR3 including eotaxin/CC chemokine ligand 11 (CCL11) may contribute to the pathogenesis of asthma. These chemokines and a growth factor (TGF-beta) may be involved in the process of airway remodelling.

OBJECTIVE

We analysed the effects of TGF-beta on the expression of CCR3 ligands in human airway smooth muscle (HASM) cells and investigated the mechanisms.

METHODS

HASM cells were cultured and treated with TGF-beta and Th2 cytokines IL-4 or IL-13. Expression of mRNA was analysed by real-time PCR. Secretion of CCL11 into the culture medium was analysed by ELISA. Transcriptional regulation of CCL11 was analysed by luciferase assay using CCL11 promoter-luciferase reporter plasmids.

RESULTS

IL-4 or IL-13 significantly up-regulated the expression of mRNAs for CCL11 and CCL26. TGF-beta alone did not increase the expression of chemokine mRNAs, but enhanced the induction of only CCL11 by IL-4 or IL-13 among CCR3 ligands. Activity of the CCL11 promoter was stimulated by IL-4, and this activity was enhanced by TGF-beta. Activation by IL-4 or IL-4 plus TGF-beta was lost by mutation of the binding site for signal transducers and activators of transcription-6 (STAT6) in the promoter. Cooperative activation by IL-4 and TGF-beta was inhibited by mutation of the binding site for nuclear factor-kappaB (NF-kappaB) in the promoter. Pretreatment with an inhibitor of NF-kappaB and glucocorticoid fluticasone propionate significantly inhibited the expression of CCL11 mRNA induced by IL-4 plus TGF-beta, indicating the importance of NF-kappaB in the cooperative activation of CCL11 transcription by TGF-beta and IL-4.

CONCLUSION

These results indicate that Th2 cytokines and TGF-beta may contribute to the pathogenesis of asthma by stimulating expression of CCL11. The transcription factors STAT6 and NF-kappaB may play pivotal roles in this process.

Cross-sectional study on respiratory effect of toner-exposed work in manufacturing plants, Japan: pulmonary function, blood cells, and biochemical markers

The aim of the study is to examine the relationship between toner-exposed work and health indices related to respiratory disorders and to confirm the baseline of a cohort study to clarify the effect of toner exposure in manufacturing plants. Subjects were 1614 male workers (809 toner-exposed workers and 805 referents) who were engaged in toner manufacturing plants in Japan (Fuji Xerox Co., Ltd). The age of subjects was from 19 to 59 years, and the average age was 40.2 years(median 40 years, SD 7.67). We conducted a pulmonary function test (PEFR, VC, FVC, FEV(1.0)%, V25/Ht) and a blood cell test (RBC, Hb, Hct, Plt, WBC, cell contents of WBC) and measured biochemical indices in blood (ALT, AST, gamma-GTP, CRP, IgE) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in urine. Student t-test and logistic regression analysis were applied to compare between the toner-exposed workers and the referents and to analyze the relationship among indices of effects and independent factors. There was no significant difference between the two groups in blood cell count and biochemical indices. Inflammation- and allergy-related markers such as 8OHdG and IgE also showed no significant difference between toner-exposed workers and the referents. The influence of smoking on pulmonary function indices was observed, but there was no relationship between the pulmonary function and toner-exposed work. In this article, we report a preliminary cross-sectional analysis in the subjects of a cohort study. No difference in pulmonary function indices was observed between the toner-exposed workers and the referents, and there was no consistent relationship between the exposure status and examined indices; however, the prevalence of subjective respiratory symptoms was higher in the exposed workers as presented in another report. Further analysis is important in the ongoing cohort study to clarify the effect of toner exposure on respiratory systems.

Synthetic double-stranded RNA induces multiple genes related to inflammation through Toll-like receptor 3 depending on NF-kappaB and/or IRF-3 in airway epithelial cells

BACKGROUND

We hypothesized that synthetic double-stranded (ds)RNA may mimic viral infection and induce expression of genes related to inflammation in airway epithelial cells.

OBJECTIVE

We analysed what gene was up-regulated by synthetic dsRNA poly I : C and then focused this study on the role of Toll-like receptor 3 (TLR3), a receptor of dsRNA and its transcriptional pathway.

METHODS

Airway epithelial cell BEAS-2B and normal human bronchial epithelial cells were cultured in vitro. Expression of targets RNA and protein were analysed by PCR and ELISA. Localization of TLR3 expression in the cells was analysed with flow cytometry. To analyse the role of TLR3 and transcription factors, knockdown of these genes was performed with short interfering RNA (siRNA).

RESULTS

Real-time PCR revealed that poly I : C significantly increased the expression of mRNAs for chemokines IP-10, RANTES, LARC, MIP-1alpha, IL-8, GRO-alpha and ENA-78 and cytokines IL-1beta, GM-CSF, IL-6 and the cell adhesion molecule ICAM-1 in both cell types. Increases in protein levels were also observed. Expression of these genes was significantly inhibited in BEAS-2B cells in which TLR3 expression was knocked down. However, pre-treatment with anti-TLR3 mAb, which interferes with the function of TLR3 expressed on the cell surface, did not inhibit the genes expression and these data were concordant with the results that TLR3 was expressed inside airway epithelial cells. The study of siRNA for NF-kappaB and IRF3 showed that they transduce the signal of poly I : C, but their roles were different in each target gene.

CONCLUSION

TLR3 is expressed inside airway epithelial cells and transduces synthetic dsRNA signals. These signals may increase expression of inflammatory cytokines, chemokines and ICAM-1 through activation of transcription factors NF-kappaB and/or IRF3 in airway epithelial cells.

Construction of a Transplantable Tissue-Engineered Artificial Peritoneum

BACKGROUND

Peritoneal defects lead to serious postoperative problems. Thus the development of physiological material to cover peritoneal defects is very desirable.

AIM

The aim of this study was to develop a transplantable artificial peritoneum.

METHOD

The artificial peritoneum consisted of collagen gel, fibroblasts, and mesothelial cells, and histological features were analyzed. The artificial peritoneum at the site of a peritoneal defect in the rat was transplanted to the abdominal wall.

RESULTS

Histological examination revealed that the artificial peritoneum consisted of a flat mesothelial monolayer upon a stromal matrix. All transplanted artificial peritoneums adapted well to the host and prevented severe adhesion.

CONCLUSION

Our artificial peritoneum may be a useful transplantable bioengineered material for repair of surgical peritoneal defects.

Double-stranded RNA activates RANTES gene transcription through co-operation of nuclear factor-kappaB and interferon regulatory factors in human airway epithelial cells

BACKGROUND

Regulated on activation, normal T cells expressed and secreted (RANTES) is a member of the CC chemokine family and contributes to viral-induced airway inflammation including exacerbations of asthma. Double-stranded RNA (dsRNA) is known to be synthesized during replication of many viruses and a ligand of Toll-like receptor 3. We hypothesized that dsRNA may mimic viral infection and induce RANTES expression in airway epithelial cells.

OBJECTIVE

We first confirmed that dsRNA up-regulated RANTES mRNA and protein synthesis in the airway epithelial cells. We next focused our studies on the transcriptional regulation of RANTES.

METHODS

Airway epithelial cell line BEAS-2B and normal human bronchial epithelial cells were used in vitro study. Levels of RANTES mRNA and protein expression were determined with RT-PCR and ELISA. Mechanisms of transcriptional regulation were assessed by electrophoretic mobility shift assay and dual luciferase assay using RANTES promoter-luciferase reporter plasmids.

RESULTS

Activation of nuclear factor-kappaB (NF-kappaB) was confirmed by nuclear protein binding to a DNA probe derived from the RANTES promoter. Activity of the RANTES promoter was increased by dsRNA. The stimulation with dsRNA was partially inhibited in plasmids mutated at either of the binding sites for NF-kappaB or IFN regulatory factors (IRFs). When both sites were mutated, the activation was totally abrogated.

CONCLUSION

These results imply that dsRNA activates NF-kappaB and IRFs and these transcription factors activate transcription of the RANTES promoter and its protein expression in airway epithelial cells.

Simulated microgravity culture system for a 3-D carcinoma tissue model

An in vitro organotypic culture model is needed to understand the complexities of carcinoma tissue consisting of carcinoma cells, stromal cells, and extracellular matrices. We developed a new in vitro model of carcinoma tissue using a rotary cell culture system with four disposable vessels (RCCS-4D) that provides a simulated microgravity condition. Solid collagen gels containing human pancreatic carcinoma NOR-P1 cells and fibroblasts or minced human pancreatic carcinoma tissue were cultured under a simulated microgravity condition or a static Ig condition for seven days. NOR-P1 cultures subjected to the simulated microgravity condition showed greater numbers of mitotic, cycling (Ki-67-positive), nuclear factor-kappa B-activating cells, and a lower number of apoptotic cells than were shown by cultures subjected to the static Ig condition. In addition, human pancreatic carcinoma specimens cultured under the simulated microgravity condition maintained the heterogeneous composition and cellular activity (determined by the cycling cell ratio and mitotic index) of the original carcinoma tissue better than static culture conditions. This new 3-D rotary cell culture system with four disposal vessels may be useful for in vitro studies of complex pancreatic carcinoma tissue.

Modulation of bronchial epithelial cells by IL-17

BACKGROUND

The induction of epithelial cytokines/chemokines is crucial in the migration of leukocytes, and its regulatory mechanisms remain incompletely defined.

OBJECTIVE

To determine the role of IL-17, a CD4(+) T cell-derived cytokine, in modulation of primary bronchial epithelial cells, the expression of IL-6, IL-8, and intercellular adhesion molecule 1 (ICAM-1) and the potential involvement of mitogen-activated protein (MAP) kinases in IL-17-mediated signaling were examined.

METHODS

The levels of gene expression and protein production for IL-6 and IL-8 in IL-17-treated cells, in the presence or absence of MAP kinase inhibitors, were analyzed by RT-PCR and ELISA, respectively, and activation of MAP kinases was determined by Western blot analyses.

RESULTS

We showed first that IL-17 induced time-dependent expression of IL-6 and IL-8 but not of the chemokines eotaxin and RANTES. In addition, IL-17 induced activation of extracellular signal-regulated kinase 1/2 but not of p38 or JNK kinases. A selective MAP kinase kinase inhibitor, PD98059, inhibited IL-17-induced IL-6 and IL-8. A combination of IL-17 and each of the cytokines IL-4, IL-13, and IFN-gamma further enhanced IL-8 expression. IL-17 alone did not induce ICAM-1 expression and showed no effect on IL-4- or IL-13-induced ICAM-1 expression. In contrast, a combination of IL-17 and IFN-gamma augmented IL-6 and ICAM-1 expression.

CONCLUSION

These findings suggest that IL-17, alone or in combination with other cytokines, modulates airway inflammation via-in part-the expression of epithelial IL-6, IL-8, and ICAM-1.

Influenza virus A stimulates expression of eotaxin by nasal epithelial cells

BACKGROUND

Respiratory virus is one of the most common causes of airway inflammation, but its pathogenic mechanisms are not well understood. Eotaxin is a potent eosinophil chemoattractant and is a selective agonist for C-C chemokine receptor 3 (CCR3). Although it has recently been demonstrated that epithelial cells express eotaxin, both in vivo and in vitro, there are few data concerning the expression in viral infection.

OBJECTS

We hypothesized that eotaxin may play an important role in attracting inflammatory cells into the airway after viral infection and analysed whether viral infection induces eotaxin in nasal epithelial cells in vitro.

METHODS

Nasal epithelial cells obtained from polypectomy for nasal polyp were infected with influenza virus A (subtype H3N2). The cells and supernatants were collected 8, 24 and 48 h after infection. Eotaxin mRNA was analysed by RT-PCR. Eotaxin concentration in the supernatants was analysed by enzyme-linked immunosorbent assay. We also examined a blocking assay to analyse the intervention of pro-inflammatory cytokines, TNF-alpha and IL-1beta in eotaxin production induced by influenza virus.

RESULTS

The results showed that eotaxin was expressed constitutively in uninfected cells, but was up-regulated for both mRNA and protein levels in infected cells. Blocking experiments using anti-TNF-alpha and anti-IL-1beta antibodies showed no effects of these agents on the level of eotaxin. In addition, UV-inactivated virus did not enhance the expression of eotaxin.

CONCLUSIONS

These results suggest that influenza virus A infection in nasal epithelial cells stimulates the expression of eotaxin, and may play an important role in the pathogenesis of airway inflammation by inducing eotaxin.

Expression of eotaxin by normal airway epithelial cells after influenza virus A infection

BACKGROUND

Viral infection is known to cause lung inflammatory disease, including bronchial asthma. The mechanisms of inflammatory cell accumulation into the airways after viral infection are not well understood. Eotaxin is a CC chemokine which is a potent and specific agonist for CC chemokine receptor 3 (CCR3). CCR3 is expressed on eosinophils, basophils and T lymphocytes. These cells are known to be key cells in the pathogenesis of asthma. Although it has recently been demonstrated that airway epithelial cells express eotaxin in vivo and in vitro, there are few data about its epxression in viral infection. We hypothesized that eotaxin may play an important role in attracting inflammatory cells to the airways after viral infection, and analyzed whether viral infection attracts eotaxin in bronchial epithelial cells in vitro.

METHODS

Human airway epithelial cells obtained from bronchial tissue at lobectomy for lung cancer were infected with influenza virus A (subtype H3N2). The cells and cultured media were collected 8, 24, and 48 h after infection. Eotaxin mRNA was analyzed with reverse transcriptase-polymerase chain reaction. Eotaxin protein levels in the culture media were analyzed by enzyme-linked immunosorbent assay. We also studied a blocking assay to analyze the intervention of proinflammatory cytokines in its production induced by influenza virus.

RESULTS

Eotaxin mRNA appeared to be expressed constitutively in uninfected cells but was expressed more clearly in infected cells. Eotaxin protein release into culture media significantly increased after infection. Anti-TNF-alpha and anti-IL-1beta antibodies did not alter the eotaxin protein levels after viral infection.

CONCLUSIONS

These results suggest that influenza virus A infection in airway epithelial cells activates the expression of eotaxin and that eotaxin may participate in the pathogenesis of airway inflammatory disease caused by viral infection, such as infectious type asthma.

[The correlation between the exacerbation of bronchial asthma and picornavirus (human rhino virus) infection in throat gargles by RT-PCR]

Viral infection is one of important factors to cause the exacerbation of bronchial asthma. We have investigated 167 adults of asthmatics to clarify the correlation between viral infection and exacerbation of asthma. Patients were classified to four group by the symptoms of common cold and asthma attack. Furthermore, we have examined Picornavirus and Human rhino virus RNA from throat gargles of patients using RT-PCR (reverse transcription--polymerase chain reaction) method. Forty of 65 (61.5%) asthmatics with common cold revealed asthma attack and common cold was significantly associated with acute exacerbation of asthma (p < 0.01). We identified Picornavirus RNA, which include 113 of Human rhino virus serotypes and enterovirus, from the samples of 16 of 52 (30.8%) patients who had acute exacerbation. It was significantly higher than the detection rate of viral RNA from patient without asthma attack. Furthermore, we analyzed Human rhino virus RNA from the same samples by RT-PCR and 93.7% of Picornavirus were identified as Human rhino virus. Taken together, these findings suggest that common cold is significantly associated with the exacerbation of bronchial asthma. Human rhino virus infection might be one of important virus in this procedure.

Intravascular ultrasound imaging of the pulmonary arteries in primary pulmonary hypertension

OBJECTIVE

Intravascular ultrasound has the unique ability to provide cross-sectional images of the arterial wall. This study examined intravascular ultrasound (IVUS) images of the proximal pulmonary arteries in primary pulmonary hypertension (PPH).

METHODOLOGY

Study 1: Specimens from four patients who had died of PPH (in vitro PPH group) were compared with those of three patients who had died of subarachnoid haemorrhage but had no evidence of cardiopulmonary disease (in vitro control group). Three-centimetre segments of the following levels were examined by IVUS: pulmonary trunk, eight secondary branch arteries of the upper, middle, and lower lobes of both lungs, and the thoracic descending aorta. Study 2: Four patients with PPH (in vivo PPH group) and five patients without pulmonary hypertension and no evidence of cardiopulmonary disease (in vivo control group) were examined. The IVUS images of the apical segmental artery of the right upper lobe and the descending branch of the right pulmonary artery were studied.

RESULTS

Echographic examination of formalin-fixed preparations of secondary branch sections of the pulmonary artery failed to show a clear three-layer structure in the in vitro control group (24 preparations), but a distinct three-layer structure and increased vessel wall thickness were observed in the in vitro PPH group (32 preparations). Similar findings were obtained in the in vivo study. The mean echo density of the proximal pulmonary arterial wall correlated well with the mean pulmonary arterial pressure (mPA) in the in vitro PPH, and also correlated with the mPA in the in vivo study (r = 0.960, P < 0.0001). The echo intensity of secondary branch sections of the pulmonary artery was higher in the in vitro PPH group than in the in vitro control group (180.5 +/- 27.0 vs 132.5 +/- 26.7 counts, P < 0.001); similar results were obtained in the in vivo study (144.7 +/- 23.4 vs 85.0 +/- 14.3 counts, P < 0.01).

CONCLUSIONS

These results suggest that the histological changes detected in the pulmonary artery walls in the PPH group were responsible for the increased echo intensity.

[Effect of IL-17 on ICAM-1 expression of human bronchial epithelial cells, NCI-H 292]

Bronchial asthma is characterized as a chronic inflammation of the airway infiltrated by eosinophils, lymphocytes, and neutrophils. ICAM-1 expression on airway epithelium facilitates adhesion between these inflammatory cells and bronchial epithelial cells, and induces the activation of inflammatory cells. ICAM-1 expression was affected by various cytokines, such as IL-17. IL-17 is a novel cytokine released by CD4+ activated memory T cells. In this study, we examined the effect of IL-17 on ICAM-1 expression by RT-PCR and flow cytometry. Human bronchial epithelial cells, NCI-H 292 cells, were stimulated with IL-17 (100 ng/ml) and/or IFN-gamma (100 U/ml). ICAM-1 was expressed constitutively. IL-17 alone did not enhance ICAM-1 expression on NCI-H 292 cells. However, IL-17 synergistically enhanced ICAM-1 expression induced by IFN-gamma. These results suggest that IL-17 has an effect on ICAM-1 expression of bronchial epithelial cells in airway inflammation.

Structural study on a sulfated polysaccharide-peptidoglycan complex produced by Arthrobacter sp

The structure of a sulfated polysaccharide-peptidoglycan complex (SP-PG) produced by Arthrobacter sp. was analyzed by NMR spectroscopy. In addition, oligosaccharide fragments of the SP-PG-L obtained by HF degradation were analyzed by NMR spectroscopy. These findings indicated that the sulfated polysaccharide (SP) contains a repeating unit composed of two galactofuranosides and a glucopyranoside. The main chain of the trisaccharide is [-->6) beta-D-Galf(1-->6)-beta-D-Galf(1-->ln, with beta-D-Glcp linked to one of the Galfs through a (1-->2) linkage. The sulfated positions of the trisaccharide were identified as C-3 and C-5 of the beta-glucosylated Galf residues, and C-2 or C-3 of the other Galf residue.

Carcinoma of the pancreas associated with anomalous junction of pancreaticobiliary tracts: report of two cases and review of the literature

We report two cases of carcinoma of the pancreas with anomalous junction of the pancreaticobiliary tracts. A 71-year-old Japanese woman had obstructive jaundice. Ultrasonography showed a hypoechoic mass in the pancreatic head and computed tomography demonstrated a low-density nodule in the pancreatic head. Endoscopic retrograde cholangiopancreatography displayed a double duct sign and an anomalous junction of the pancreaticobiliary tracts. The patient underwent a pancreatoduodenectomy. The histopathologic diagnosis of the resected specimen was adenocarcinoma of the pancreatic head. A 56-year-old Japanese man also developed obstructive jaundice. Ultrasonography and computed tomography showed a huge mass almost replacing the whole pancreas and involving the superior mesenteric artery, splenic artery, splenic vein, and portal vein. Multiple hepatic metastases and peritoneal dissemination were present. Endoscopic retrograde cholangiopancreatography demonstrated an anomalous junction of the pancreaticobiliary tracts. The patient died of hemorrhage from esophageal varices. We discuss the relationship between the anomalous junction of the pancreaticobiliary tracts and pancreatic carcinoma.

[Evaluation of the FREEDOM O2, DC Concentrator, a portable oxygen concentrator capable of operating under car battery power]

The FREEDOM O2 DC Concentrator, an oxygen concentrator which can be powered by a car battery, was evaluated. The oxygen concentrator was used by a 67 year-old man with sequelae of pulmonary tuberculosis who was receiving long-term oxygen therapy at home (HOT), and whose work required automobile trips over long distances. The equipment used was an adsorption-type oxygen concentrator capable of operating on a DC 12 V power supply, and which can be powered from a residential power outlet (AC 100 V) using a dedicated voltage converter. The trunk-shaped equipment measured 21/584 x 42 cm and weighed 17 kg. The noise level of the equipment was 58.2 +/- 2.5 dB (at 1 meter), and the flow rate can be set to 0.25, 0.50, 0.75, 1.0, 1.5, and 2.0 l/min.

RESULTS

1) The O2 concentration which can be generated by this equipment is 93 +/- 3% (0.25 to 1.5 l/min) or 90 +/- 2.8% (2.0 l/min). 2) Using this equipment, the patient was capable of driving himself in comfort for two hours or longer. Further, it was possible to stay in a hotel during a trip, inhaling oxygen generated by the equipment. Hereafter, this equipment should enable or facilitate long-distance driving, travel and lodging for HOT patients.

Structural studies on a sulfated polysaccharide from an Arthrobacter sp. by NMR spectroscopy and methylation analysis

Structural characterization of a sulfated polysaccharide peptidoglycan complex (SP-PG) from an Arthrobacter sp. was performed by NMR spectroscopy and methylation analysis. In order to simplify the analyses, the desulfated SP-PG was used. NMR spectroscopy revealed the presence of a trisaccharide repeating unit and a disaccharide repeating unit. The trisaccharide unit was composed of two galactofuranosides and one glucopyranoside, and the disaccharide unit was of two galactopyranosides, as shown below. The methylation analysis showed that the polysaccharide consists mainly of a 4-linked galactopyranoside, a 6-linked galactopyranoside, a 6-linked galactofuranoside, a 2,6-linked galactofuranoside, a terminal galactopyranoside and a terminal glucopyranoside. These findings confirmed the structure indicated by the NMR spectroscopy. The repeating units determined in this study are novel.

DX-8951f, a water-soluble camptothecin analog, exhibits potent antitumor activity against a human lung cancer cell line and its SN-38-resistant variant

We previously reported that DX-8951f, a novel water-soluble camptothecin analog, significantly inhibits the growth of various human and murine tumors in vitro and in vivo. The antitumor effects and topoisomerase I inhibitory activity of DX-8951f are stronger than those of other current camptothecin analogs. In this study, we established an SN-38-resistant cell line, PC-6/SN2-5, from the human oat cell carcinoma PC-6 cell line by a stepwise selection system, investigated the mechanism of resistance of this cell line and then compared the antitumor activity of camptothecin analogs against the cell line. PC-6/SN2-5 cells were resistant to SN-38 (32-fold) and SK&F 104864 (topotecan; 14-fold), but barely resistant to CPT-11 (3-fold) and DX-8951f (2-fold). Topoisomerase I protein levels and topoisomerase I activities of parental cells were similar to those of resistant cells. Determination of the cellular drug concentration by either flow cytometric analysis or the high-performance liquid chromatography method confirmed that the cellular accumulation of SN-38 and topotecan was significantly reduced in PC-6/SN2-5 cells, whereas that of DX-8951f was only slightly reduced. Furthermore, DX-8951f stabilized the cleavable complex formations in intact PC-6/SN2-5 cells as well as in parental cells, but SN-38 and topotecan did not in the resistant cells. Our data suggest that PC-6/SN2-5 cells may have acquired resistance to camptothecin analogs by a decrease in intracellular drug accumulation and that DX-8951f may have the potency to overcome such a type of resistance mechanism induced by camptothecin compounds.

[Simultaneous ambulatory electrocardiography and pulse oximetry]

We developed a system for 24-hour ambulatory recording of blood oxygenation (SpO2) and electrocardiography (ECG). Using this system, we studied 10 healthy volunteers and 7 patients with chronic pulmonary diseases. The system incorporated a portable pulse oximeter (SM50) manufactured by Fukuda Denshi KK; the first and second channels were used to record ECG data and the third was used to record SpO2 data. An SpO2 sensor (Dispo-sensor D-25; Nellcor Inc.) was applied to the fourth of fifth finger. The SpO2 data (MicrO2; Siemens AG) were digitized and stored in the ambulatory recording device; the ECG was recorded simultaneously. The data were analyzed with a model DMW-9000H analyzer (Fukuda Denshi KK). A custom-designed program was also used, to remove noise errors. In the healty volunteers, SpO2 was at least 90% for the entire 24 hours. In all the patients, SpO2 fell below 90% at rest during the night or after a 15-minute walk. Transient atrial tachycardia was observed in 3 patients, and during the tachycardia the SpO2 was low. The number of extra ventricular beats divided by the total number of beats increased more in the patients than in the healthy volunteers (1.21 +/- 0.89 vs 0.6 +/- 0.3%, p < 0.05). SpO2 did not change significantly in the patients. In outpatients and in patients receiving home health care, the present system facilitates simultaneous diagnosis of respiratory failure an arrhythmias. In patients with chronic pulmonary diseases desaturation may cause transient atrial tachycardia.

[Pulmonary typical carcinoid with metastases to pulmonary hilar, and mediastinal lymph nodes]

A 50-year-old woman was admitted to our hospital complaining of recurrent bloody sputum and hemoptysis. Chest X-ray films showed an infiltrative shadow in the left lower lung field. Chest computed tomograms showed a nodular tumor shadow near the left B8 and this tumor shadow was found between A8 and A9 by pulmonary arteriography. Bronchoscopic examination revealed a red coagulum in the left B8 and cytologic examination of broncho alveolar lavage fluid revealed atypical squamous cells. With a clinical diagnosis of squamous cell carcinoma of the lung, a left lower lobectomy with hilar and mediastinal lymph node dissection was done. A milk-white tumor was found in the lower lobe of the resected lung. The pathological diagnosis of the resected tissue specimen was carcinoid, accompanied by pulmonary, hilar, and mediastinal lymph node metastases. Reduced immunofluorescence by Chromogranin A and serotonin staining were further evidence that the tumor was atypical. This case is very interesting in that the tumor metastasized to the lung and lymph nodes, even-though it was pathologically typical.

Inhibitory activity of camptothecin derivatives against acetylcholinesterase in dogs and their binding activity to acetylcholine receptors in rats

A camptothecin derivative, 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), shows a potent antitumour activity in experimental tumour models and in clinical trials. However, CPT-11 induced early diarrhoea and vomiting at high dose levels in clinical studies and showed an acetylcholine-like action on the guinea-pig ileum and trachea. In the present study, we investigated the activities of camptothecin derivatives in inhibiting acetylcholinesterase (AChE) and in binding to muscarinic acetylcholine receptors (AChR). CPT-11 inhibited AChE and binding of the specific ligand to AChR with respective 50% inhibition concentrations of 0.2 and 5 microM. These inhibitions were induced by camptothecin derivatives having an amino group at the C-10 position (or the C-4 position of hexacyclic derivatives), but were not or were only slightly induced by the others. Early defecation and vomiting in dogs were observed after intravenous injection of DU-6596 and DU-6888, two hexacyclic derivatives having the aminomethyl group at the C-4 position, and of CPT-11. DU-6174, however, which has a hydroxy group at this position, induced no early defecation and little vomiting. Plasma concentrations of CPT-11, DU-6596 and DU-6888 after intravenous treatment at doses causing such early adverse effects were maintained for 1 h or longer at levels sufficient to inhibit AChE. These results suggest that the inhibition of AChE by camptothecin derivatives with an amino group at the C-10 position (or the C-4 position) relates to the early defecation or diarrhoea and vomiting.

Camptothecin analog (CPT-11)-sensitive human pancreatic tumor cell line QGP-1N shows resistance to SN-38, an active metabolite of CPT-11

In the course of our study to determine the cross-sensitivity between CPT-11 and its active metabolite, SN-38, we found a SN-38-resistant human pancreatic tumor cell line, QGP-1N, which shows sensitivity to CPT-11. The IC50 of SN-38 was 152 times greater for QGP-1N than for SUIT-2, also a human pancreatic tumor cell line, whose IC50 of CPT-11 was similar to that for QGP-1N. The uptakes of CPT-11 and SN-38 and the intracellular conversion of CPT-11 to SN-38 could not explain the difference in sensitivity. DNA synthesis of QGP-1N cells was inhibited by CPT-11 which did not affect that of SUIT-2, while SN-38 inhibited the DNA synthesis of SUIT-2 at lower concentrations than that of QGP-1N. The inhibition test of topoisomerase I catalytic activity by CPT-11 or SN-38 revealed no difference in the biochemical properties of the topoisomerase I enzymes to the compounds between these two cell lines. These results indicate that CPT-11 should have its own inhibitory effect on DNA synthesis through a yet unknown mechanism in QGP-1N cells, although SN-38 plays an essential role in the antitumor activity of CPT-11 in SUIT-2 cells. In some cases, the antitumor effect of CPT-11 might be consequent not only on SN-38 but also on CPT-11 itself.

Intracellular roles of SN-38, a metabolite of the camptothecin derivative CPT-11, in the antitumor effect of CPT-11

It is known that 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11), a semisynthesized derivative of camptothecin (CPT), has a potent antitumor activity in vivo, but 7-ethyl-10-hydroxycamptothecin (SN-38), a metabolite of CPT-11, shows much stronger cytotoxicity in vitro than CPT-11. In this study, we demonstrated that the relaxation of SV40 DNA plasmids by type I DNA topoisomerase prepared from P388 murine leukemia cells was inhibited by 50% by SN-38 at approximately 1 microM, although CPT-11 at 1 mM slightly inhibited the relaxation. SN-38 and CPT showed strong, time-dependent inhibitory activity against DNA synthesis of P388 cells. However, CPT-11 weakly inhibited DNA synthesis independently of time with coincident inhibition of the total thymidine uptake by the cells. By alkaline and neutral elution assays, it was demonstrated that SN-38 caused much more frequent DNA single-strand breaks in P388 cells than did CPT-11. The same content of SN-38 and a similar frequency of single-strand breaks were detected in the cells treated with SN-38 at 0.1 microM or with CPT-11 at 100 microM. Therefore, single-strand breaks by CPT-11 seem to be due to SN-38 produced from CPT-11 in cells. These results indicate that CPT-11 itself possesses a marginal antiproliferative effect but that SN-38 plays an essential role in the mechanism of action of CPT-11.

Stimulation of all T cells bearing V beta 1, V beta 3, V beta 11 and V beta 12 by staphylococcal enterotoxin A

To determine the molecular mechanisms of T cell stimulation by staphylococcal enterotoxin A (SEA), we examined the expression of T cell receptor (TcR) V beta on the T cells from four strains of mice stimulated in vitro with SEA, using flow cytometric analysis for the number of T cells bearing V beta 3, V beta 6, V beta 8, V beta 11 and RNA blotting analysis for the amount of transcripts of V beta 1, V beta 5 and V beta 12. The number of T cell blasts bearing V beta 1, V beta 3, V beta 1 or V beta 12 were increased in the T cell blasts proliferating in vitro in response to SEA in C57BL/6 mice. In AKR/J mice, which contain few V beta 11- or V beta 12-bearing T cells due to a tolerance to the self-MHC class II IE-antigens, T cells bearing V beta 1 or V beta 3 responded to SEA. SEA enriched only V beta 1-bearing T cells in BALB/c mice carrying Mls-2a which lack Mls-1a-reactive V beta 3-bearing T cells as well as V beta 11- and V beta 12-bearing T cells. In spite of the presence of V beta 1-bearing T cells, C3H/He T cells exhibited a very low responsiveness to SEA. T cell repertoires skewed by clonal deletion of self-reactive T cells may in part account for the different sensitivity to SEA among the different strains. A tolerance to SEA can be established in C57BL/6 mice which have been primed i.v. with SEA and treated i.p. with 200 mg/kg of cyclophosphamide 2 days later. All mature T cells bearing V beta 3 or V beta 11 were virtually abolished in the periphery of tolerant mice. These results suggest that most T cells reactive to SEA bear V beta 1, V beta 3, V beta 11 or V beta 12 and that clonal deletion of mature T cells reactive to SEA may account for the cellular mechanisms for cyclophosphamide-induced tolerance to SEA.

Ultrastructural investigations on the anterior adductor muscle of a brachiopoda, Lingula unguis

The brachiopoda, Lingula unguis, has a pair of anterior adductors located in the center of the shell. Each muscle consists of an opaque and a translucent portion which is constructed of smooth and obliquely-striated muscle respectively. According to our ultrastructural observations, the opaque portion seems to have two types of cells. They differ only in the diameters of their thick myofilaments. The fine structure of their cell organelles resembles each other. We measured the diameters of the thick myofilaments in each type of cell to distinguish between the two cell types. About 500 measurements of myofilament diameters were made for each type of cell and statistically analyzed. For one type of cell, the distribution of diameters of the thick myofilaments fit a normal distribution curve with a peak at 37-60 nm. The distribution of diameters of the thick myofilaments for the other type fit a curve in which two normal distribution curves having peaks at 37-60 and 75-97 nm respectively partially overlapped. According to these results, we suggest that the opaque portion contains two types of cells, each having a different distribution of thick myofilament sizes.

Jietacins A and B, new nematocidal antibiotics from a Streptomyces sp. Taxonomy, isolation, and physico-chemical and biological properties

Jietacins A and B, new azoxy antibiotics, were isolated from the culture broth of a streptomycete. The antibiotics have the molecular formulae of C18H34N2O2 and C19H36N2O2, respectively. Both possess an azoxy group. They have potent activity against the pine wood nematode, Bursaphelenchus lignicolus, and are weakly active against some fungi.

Clostomicins, new antibiotics produced by Micromonospora echinospora subsp. armeniaca subsp. nov. I. Production, isolation, and physico-chemical and biological properties

A soil isolate named as Micromonospora echinospora subsp. armeniaca subsp. nov. KMR-593 was found to produce at least five related antibiotics, clostomicins, active against Gram-positive bacteria including anaerobes. From the physico-chemical properties, one of these components was identified with lipiarmycin and others were found to be new antibiotics. Each component includes two chlorine atoms and the molecular weights of A and B2, C, and D are 1,058, 1,042 and 1,056, respectively. The structural differences were characterized by NMR analyses.

Adecypenol, a unique adenosine deaminase inhibitor containing homopurine and cyclopentene rings. Taxonomy, production and enzyme inhibition

Adecypenol, which exhibits potent inhibitory activity against calf intestinal adenosine deaminase (EC 3.5.4.4), was isolated from the cultured broth of Streptomyces sp. OM-3223. Adecypenol was classified as a semi-tight binding inhibitor. The Ki value against calf intestinal adenosine deaminase was 4.7 X 10(-9) M. No acute toxicity of adecypenol was observed at 100 mg/kg in mice. Adecypenol exhibited no antimicrobial activity against various bacteria and fungi at the concentration of 1.0 mg/ml.

Adechlorin, a new adenosine deaminase inhibitor containing chlorine production, isolation and properties

Adechlorin exhibiting a potent inhibitory activity against calf intestinal adenosine deaminase was isolated from the cultured broth of Actinomadura sp. OMR-37. The molecular formula was C11H15N4O4Cl. The aglycone of adechlorin was identical with that of the known adenosine deaminase inhibitors coformycin and 2'-deoxycoformycin. Adechlorin did not exhibit inhibitory activity against various bacteria and fungi at 1.0 mg/ml. The Ki values for adechlorin, coformycin and 2'-deoxycoformycin against adenosine deaminase were determined to be 5.3 X 10(-10) M, 2.1 X 10(-10) M and 7.6 X 10(-11) M, respectively. Adechlorin as well as coformycin and 2'-deoxycoformycin enhanced the antiviral activity of Ara-A. The acute toxicity of adechlorin in mice was less than those of coformycin and 2'-deoxycoformycin.