Fiber-based modulated optical reflectance configuration allowing for offset pump and probe beams

A new fiber-based modulated optical reflectance configuration is developed in this work. The technique maintains the fiber-based heating laser (pump) and detection laser (probe) in close proximity at a fixed separation distance in a ceramic ferrule. The pump beam periodically heats the sample inducing thermal waves into the sample. The probe beam measures the temperature response at a known distance from the pump beam over a range of heating modulation frequencies. The thermal diffusivity of the sample may be calculated from the phase response between the input heat flux and the temperature response of a sample having a reflective surface. The unique measurement configuration is ideal for in situ measurements and has many advantages for laboratory-based systems. The design and development of the system are reported along with theoretical justification for the experimental design. The thermal diffusivities of Ge and SiC are measured and found to be within 10% of reported literature values. The diffusivity for SiO₂ is measured with a relative difference of approximately 100% from the literature value when the ferrule is in contact with the sample. An additional measurement was made on the SiO₂ sample with the ferrule not in contact resulting in a difference of less than 2% from the literature value. The difference in the SiO₂ measurement when the ferrule is in contact with the sample is likely due to a parallel heat transfer path through the dual-fiber ferrule assembly.

Regulation of eotaxin-3/CC chemokine ligand 26 expression by T helper type 2 cytokines in human colonic myofibroblasts

Eotaxins induce the trafficking of eosinophils to the sites of inflammation via CC chemokine receptor 3 (CCR3). In this study, we investigated eotaxin-3/CC chemokine ligand 26 (CCL26) expression in the inflamed mucosa of patients with inflammatory bowel disease (IBD), and characterized the molecular mechanisms responsible for eotaxin-3 expression in human colonic myofibroblasts. Eotaxin-3 mRNA and protein expression was evaluated by real time-polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Eotaxin-3 mRNA expression was elevated significantly in the active lesions of ulcerative colitis (UC) patients. Significant elevations were also observed in the active lesions of Crohn's disease (CD) patients, but this was significantly lower than that detected in the active UC lesions. There were no significant increases in the inactive lesions of UC or CD patients. Colonic myofibroblasts were identified as a major source of eotaxin-3 in the colonic mucosa, and interleukin (IL)-4 and IL-13 enhanced eotaxin-3 mRNA and protein expression significantly in these cells. There was a significant positive correlation between mucosal eotaxin-3 and IL-4 mRNA expression in the active lesions of IBD patients. The IL-4- and IL-13-induced eotaxin-3 mRNA expression was regulated by the signal transducer and activator of transcription-6 (STAT-6) and suppressor of cytokine signalling (SOCS)1-mediated pathways. Interferon (IFN)-γ acts as a negative regulator on the IL-4- and IL-13-induced eotaxin-3 expression via STAT-1 activation. Eotaxin-3 expression was elevated specifically in the active lesions of IBD, in particular UC. Eotaxin-3 derived from colonic myofibroblasts may play an important role in the pathophysiology of UC.

Epithelial expression of interleukin-37b in inflammatory bowel disease

Interleukin (IL)-37 is a member of the IL-1 cytokine family. We investigated IL-37b expression in the inflamed mucosa of inflammatory bowel disease (IBD) patients. Furthermore, we analysed IL-37b expression in human colonic epithelial cells. The human colonic epithelial cell line T84 and human colonic subepithelial myofibroblasts (SEMFs) were used. IL-37b expression in the IBD mucosa was evaluated by immunohistochemistry. IL-37b mRNA and protein expression were determined by real time-polymerase chain reaction (PCR) and Western blotting, respectively. IL-37b was not detected in the normal colonic mucosa. In the inflamed mucosa of IBD patients, epithelial IL-37b expression was increased markedly. In ulcerative colitis (UC) and Crohn's disease (CD) patients, IL-37b expression was enhanced in the affected mucosa. In the intestinal epithelial cell line T84, the expression of IL-37b mRNA and protein was enhanced by tumour necrosis factor (TNF)-α. This IL-37b induction by TNF-α was mediated by nuclear factor (NF)-κB and activator protein (AP)-1 activation. Furthermore, IL-37b inhibited TNF-α-induced interferon-γ-inducible protein (IP)-10 expression significantly in human colonic SEMFs. Epithelial IL-37b expression was increased in IBD patients, especially UC patients. IL-37b may be involved in the pathophysiology of IBD as an anti-inflammatory cytokine and an inhibitor of both innate and acquired immune responses.

Neuroradiologic features in X-linked α-thalassemia/mental retardation syndrome

BACKGROUND AND PURPOSE

X-linked α-thalassemia/mental retardation syndrome (Mendelian Inheritance in Man, 301040) is one of the X-linked intellectual disability syndromes caused by mutations of the ATRX gene and characterized by male predominance, central hypotonic facies, severe cognitive dysfunction, hemoglobin H disease (α-thalassemia), genital and skeletal abnormalities, and autistic and peculiar behavior. More than 200 patients in the world, including >70 Japanese patients, have been diagnosed with ATR-X syndrome.

MATERIALS AND METHODS

We reviewed the brain MRI and/or CT findings of 27 Japanese patients with ATR-X with ATRX mutations retrospectively.

RESULTS

The findings were categorized into 5 types: 1) nonspecific brain atrophy (17/27); 2) white matter abnormalities, especially around the trigones (11/27); 3) widespread and scattered white matter abnormalities (1/27); 4) delayed myelination (4/27); and 5) severe and rapidly progressive cortical brain atrophy (1/27).

CONCLUSIONS

This is the first report on a comprehensive study of brain MRI/CT findings of ATR-X syndrome. Our findings suggest that the ATRX protein seems to be involved in normal myelination. The classification will require revisions in the near future, but it will be helpful in establishing the relationship between ATRX mutation and brain development and understanding the ATRX protein function in the brain.

RUNX3 expression correlates with chief cell differentiation in human gastric cancers

RUNX3 is a novel tumor suppressor in gastric carcinogenesis and an important factor for differentiation of chief cells in the normal gastric fundic mucosa. In this study, we confirmed RUNX3 immunolocalization in the fundic gland (bottom part) but minimum in surface mucous cell epithelium (top part) in the isolated gland from fundic mucosa. We also analyzed RUNX3 expression by immunohistochemistry in 102 gastric cancers and made a histological assessment of the expression of differentiation markers to evaluate interrelations. Among them, 45 and 57 cases were judged to be RUNX3 positive and negative, respectively, and 33 and 69 cases were pepsinogen I positive and negative, with no link to histological types. RUNX3 expression was significantly associated with that of pepsinogen I (P<0.001), but not mucins, including MUC5AC and MUC6, or the parietal or intestinal phenotypes. In conclusion, the present study showed, for the first time to our knowledge, a relation between RUNX3 and pepsinogen I expression in human gastric cancers. RUNX3 is strongly associated with chief cell phenotypic expression in human gastric cancers, as well as in normal gastric mucosa, and could be considered to play an important role in maintaining the chief cell phenotype.

Synergistic upregulation of inducible nitric oxide synthase and cyclooxygenase-2 in gastric mucosa of Mongolian gerbils by a high-salt diet and Helicobacter pylori infection

AIMS

The intake of salt and salty food is known as a risk factor for gastric cancer. We have previously demonstrated that a high-salt diet dose-dependently enhances Helicobacter pylori (H. pylori)-associated gastritis and stomach carcinogenesis in Mongolian gerbils. In this study, we focused on the influence of excessive salt intake on the expression of inflammatory mediators involved in progression of H. pylori-induced chronic gastritis.

METHODS AND RESULTS

A total of 45 stomach samples from Mongolian gerbils were evaluated by immunohistochemistry. The animals were infected with H. pylori and fed basal (0.32%) or a high-salt (10%) diet, and sacrificed after 40 weeks. Proliferative activity and expression of cyclooxygenase-2 (COX-2) in gastric mucosa were significantly increased in H. pylori-infected gerbils. The additional high-salt diet significantly up-regulated the expression of inducible nitric oxide synthase (iNOS) and COX-2 in H. pylori-infected groups (P<0.01 and P<0.05, respectively), while no significant effects were noted in non-infected animals. There was significant synergistic interaction between H. pylori infection and 10% NaCl diet on the expression of iNOS (P<0.05) and also a tendency for enhanced COX-2 expression (P=0.0599).

CONCLUSIONS

The present results suggest that a high-salt diet works synergistically with H. pylori infection to enhance iNOS and COX-2 expression in the gastric mucosa of Mongolian gerbils, and support the hypothesis that excessive salt intake may be associated with progression of H. pylori-induced gastritis.

Expression and maturation of Sendai virus vector-derived CFTR protein: functional and biochemical evidence using a GFP-CFTR fusion protein

Sendai virus (SeV) vector has been shown to efficiently transduce airway epithelial cells. As a precursor to the potential use of this vector for cystic fibrosis (CF) gene therapy, the correct maturation of the SeV vector-derived CF transmembrane conductance regulator (CFTR) protein was examined using biochemical and functional analyses. We constructed a recombinant SeV vector, based on the fusion (F) gene-deleted non-transmissible SeV vector, carrying the GFP-CFTR gene in which the N terminus of CFTR was fused to green fluorescence protein (GFP). This vector was recovered and propagated to high titers in the packaging cell line. Western blotting using an anti-GFP antibody detected both the fully glycosylated (mature) and the core-glycosylated (immature) proteins, indicating that SeV vector-derived GFP-CFTR was similar to endogenous CFTR. We also confirmed the functional channel activity of GFP-CFTR in an iodide efflux assay. The efficient expression of GFP-CFTR, and its apical surface localization, were observed in both MDCK cells in vitro, and in the nasal epithelium of mice in vivo. We concluded that recombinant SeV vector, a cytoplasmically maintained RNA vector, is able to direct production of a correctly localized, mature form of CFTR, suggesting the value of this vector for studies of CF gene therapy.

Down regulation of gastric and intestinal phenotypic expression in Epstein-Barr virus-associated stomach cancers

AIMS

We have previously demonstrated the importance of gastric and intestinal phenotypic expression for stomach carcinogenesis. In this study, we focused on Epstein-Barr virus (EBV)-associated stomach cancers, with special attention to Cdx2.

METHODS AND RESULTS

We evaluated the expression of gastric and intestinal phenotypic markers by immunohistochemistry in 35 EBV-positive [EBV (+)] and 75 EBV-negative [EBV (-)] stomach cancers in Colombia. The lesions were divided phenotypically into gastric (G), gastric-and-intestinal mixed (GI), intestinal (I), and null (N) phenotypes. In the EBV (+) cases, the lesions were divided phenotypically into 9 G (25.7%), 1 GI (2.9%), 3 I (8.6%), and 22 N (62.9%) types. Similarly, the EBV (-) lesions were also classified phenotypically as 15 G (20.0%), 19 GI (25.3%), 24 I (32.0%), and 17 N (22.7%) types. The proportion of N type EBV (+) lesions was higher than for their EBV (-) counterparts (P<0.0001). The expression of Cdx2 and MUC2 was also found to be significantly lower in EBV (+) than in EBV (-) stomach cancers (P=0.0001; P<0.0001). Cdx2 expression in the intestinal metaplastic glands present in non-neoplastic mucosa surrounding EBV (+) lesions was also significantly lower than in EBV (-) tumors (P=0.016) despite no evidence of EBV infection.

CONCLUSIONS

EBV (+) stomach cancers are characterized by low expression of intestinal phenotype markers, including Cdx2, and only occasional gastric phenotypic expression.

Sendai virus-mediated CFTR gene transfer to the airway epithelium

The potential for gene therapy to be an effective treatment for cystic fibrosis has been hampered by the limited gene transfer efficiency of current vectors. We have shown that recombinant Sendai virus (SeV) is highly efficient in mediating gene transfer to differentiated airway epithelial cells, because of its capacity to overcome the intra- and extracellular barriers known to limit gene delivery. Here, we have identified a novel method to allow the cystic fibrosis transmembrane conductance regulator (CFTR) cDNA sequence to be inserted within SeV (SeV-CFTR). Following in vitro transduction with SeV-CFTR, a chloride-selective current was observed using whole-cell and single-channel patch-clamp techniques. SeV-CFTR administration to the nasal epithelium of cystic fibrosis (CF) mice (Cftr(G551D) and Cftr(tm1Unc)TgN(FABPCFTR)#Jaw mice) led to partial correction of the CF chloride transport defect. In addition, when compared to a SeV control vector, a higher degree of inflammation and epithelial damage was found in the nasal epithelium of mice treated with SeV-CFTR. Second-generation transmission-incompetent F-deleted SeV-CFTR led to similar correction of the CF chloride transport defect in vivo as first-generation transmission-competent vectors. Further modifications to the vector or the host may make it easier to translate these studies into clinical trials of cystic fibrosis.

Loss of MUC2 expression correlates with progression along the adenoma-carcinoma sequence pathway as well as de novo carcinogenesis in the colon

AIMS

We have previously demonstrated links between clinicopathological findings and phenotypes using several gastric and intestinal phenotypic markers in stomach and pancreatic cancers. However, the clinicopathological significance of the phenotype and Cdx2 expression has hitherto remained unclear in colorectal carcinogenesis.

METHODS AND RESULTS

We examined the correlation between gastric and intestinal phenotypic expression in 91 primary early carcinomas of the colon. MUC2 expression demonstrated a significant decrease from tubular/tubulovillous adenomas with moderate atypia, through intramucosal carcinomas, to cancers with submucosal invasion (P<0.0001). Intramucosal de novo carcinomas (flat type carcinomas without adenomatous components) exhibited a greater decrease of MUC2 than intramucosal lesions with adenomatous components. Expression of MUC5AC also decreased significantly with progression according to the tubular/tubulovillous adenoma-carcinoma sequence, carcinomas with villous adenomatous components having a higher level compared with their tubular adenomatous counterparts, suggesting differences in the pathway of malignant transformation. Cdx2 nuclear expression was maintained in all of the adenomas and early carcinomas examined.

CONCLUSIONS

Our data suggest that the reduction of MUC2 expression may be associated with the occurrence and progression of colorectal carcinomas in both adenoma-carcinoma sequence pathway and de novo carcinogenesis. Tumor-suppressive effects of Cdx2 may be preserved during early stages of colorectal carcinogenesis.

Gastric and intestinal phenotypic correlation between exocrine and endocrine components in human stomach tumors

We have previously suggested that an origin of a stomach cancer is from a progenitor cell specializing toward exocrine cell (Exo-cell) lineages. To clarify whether our hypothesis is correct or not, we analyzed the expression of Exo-cell and endocrine cell (End-cell) markers in a series of lesions for comparison. We evaluated chromogranin A (CgA) expression in 37 early and 73 advanced stomach cancers, in 30 stomach adenomas, in 8 carcinoid tumors, and in 4 endocrine cell carcinomas (ECCs) with assessment of gastric and/or intestinal (G/I) phenotypes in both Exo-cell and End-cell by immunohistochemistry. CgA expression was observed in 10.8% of the early and 16.4% of the advanced stomach cancers, respectively. The End-cell G/I phenotypes were in line with the Exo-cell counterparts in the CgA-positive stomach cancerous areas, and there was strong association between Cdx2 expression and the intestinal End-cell markers. All of the adenoma cases had the intestinal Exo-cell phenotypic expression, with the positive link between Exo-cell and End-cell G/I phenotypes. All stomach carcinoids had CgA expression but no expression of Exo-cell markers. In conclusion, most stomach cancers might develop from a progenitor cell specializing towards Exo-cell lineages, but some cases possessed both Exo-cell and End-cell markers with maturely differentiated phenotypes. In such cases, Exo-cell and End-cell phenotypes were found to correlate strongly, suggesting the possibility of histogenesis from "cancer stem cells".

Laser cooling transitions in atomic erbium

We discuss laser cooling opportunities in atomic erbium, identifying five J ? J + 1 transitions from the 4f126s2 3H6 ground state that are accessible to common visible and near-infrared continuous-wave tunable lasers. We present lifetime measurements for the 4f11(4Io 15/2)5d5/26s2 (15/2, 5/2)7o state at 11888 cm-1 and the 4f11(4Io 13/2)5d3/26s2 (13/2, 5/2)7o state at 15847 cm-1, showing values of 20 +/- 4 micros and 5.6 +/- 1.4 micros, respectively. We also present a calculated value of 13 +/- 7 s-1 for the transition rate from the 4f11(4Io 15/2)5d3/26s2 (15/2, 3/2)7 o state at 7697 cm-1 to the ground state, based on scaled Hartree-Fock energy parameters. Laser cooling on these transitions in combination with a strong, fast (5.8 ns) laser cooling transition at 401 nm, suggest new opportunities for narrowband laser cooling of a large-magnetic moment atom, with possible applications in quantum information processing, high-precision atomic clocks, quantum degenerate gases, and deterministic single-atom doping of materials.

Molecular cloning of a novel importin alpha homologue from rice, by which constitutive photomorphogenic 1 (COP1) nuclear localization signal (NLS)-protein is preferentially nuclear imported

Nuclear import of proteins that contain classical nuclear localization signals (NLS) is initiated by importin alpha, a protein that recognizes and binds to the NLS in the cytoplasm. In this paper, we have cloned a cDNA for a novel importin alpha homologue from rice which is in addition to our previously isolated rice importin alpha1a and alpha2, and we have named it rice importin alpha1b. In vitro binding and nuclear import assays using recombinant importin alpha1b protein demonstrate that rice importin alpha1b functions as a component of the NLS-receptor in plant cells. Analysis of the transcript levels for all three rice importin alpha genes revealed that the genes were not only differentially expressed but that they also responded to dark-adaptation in green leaves. Furthermore, we also show that the COP1 protein bears a bipartite-type NLS and its nuclear import is mediated preferentially by the rice importin alpha1b. These data suggest that each of the different rice importin alpha proteins carry distinct groups of nuclear proteins, such that multiple isoforms of importin alpha contribute to the regulation of plant nuclear protein transport.

Portal hypertensive enteropathy in biliary atresia

This paper describes a rare case of biliary atresia (BA) in which massive postoperative bleeding developed due to portal hypertensive enteropathy. A 15-year-old boy had been doing well after Kasai's operation for BA. At around the age of 6 years he developed recurrent episodes of esophageal variceal bleeding and underwent esophageal transection, splenectomy, sclerotherapy, and embolization of the left gastric vein. At the age of 15 years he suddenly developed abdominal pain, hematemesis, and massive tarry stools. His hemoglobin level was 6.3 g/dl. Endoscopy showed several small, polypoid lesions in the jejunum beyond Treitz' ligament. The source of the bleeding was one of these lesions located in the proximal jejunojejunostomy of the Roux-en-Y loop. Because he had repeated episodes of melena, he underwent partial resection of the jejunum under endoscopic guidance. He has since been free of gastrointestinal (GI) bleeding. From this experience, we conclude that the polypoid lesions of an enteropathy may be a cause of massive GI bleeding in the postoperative portal hypertension of BA.

Transumbilical resection and umbilical plasty for patent omphalomesenteric duct

This paper describes a transumbilical resection and umbilical plasty for treatment of a patent omphalomesenteric duct (POMD). In a newborn infant with a POMD, a skin incision was made circumscribing the mucocutaneous junction of the protruded duct. The duct was completely extirpated with a wedge resection of the connection to the intestine and an umbilical plasty was performed. The postoperative appearance was excellent. It appears that transumbilical resection and umbilical plasty may be a satisfactory operation for POMD.

Abdominal wall plasty for a premature infant with congenital diaphragmatic hernia

This paper reports a premature infant with a congenital diaphragmatic hernia (CDH) who underwent an abdominal wall plasty to enlarge the abdominal cavity, one of twin infants born at 32 weeks weighing 1,255 g. After stabilization, the herniated viscera were reduced from the pleural cavity and the abdominal wall muscle and skin layers were replaced by a Gore-tex patch without closure of the diaphragmatic defect. Respiratory and circulatory conditions were stable during the perioperative period. Postoperatively, a roentogenogram showed expansion of the lung. However, his condition deteriorated 24 h after surgery, triggered by intratracheal suction, and he died on the 4th day of life despite the use of high-frequency oscillation, catecholamines, and vasodilators. Postmortem examination showed severely hypoplastic lungs. Abdominal wall plasty may be a less invasive initial procedure, however, further studies, such as comparison with the standard method or conservative management, are needed using a large clinical group or animal models to justify the usefulness of this procedure.

Infarcted intestinal volvulus detected by prenatal ultrasonography

This article describes a prenatal ultrasonographic finding of an infarcted intestinal volvulus. Ultrasonography showed polyhydramnios, multiple dilated intestinal loops, increased transverse abdominal area, and ascites. After cesarean section due to premature rupture of membranes and fetal distress, derotation of the infarcted volvulus caused postoperative thrombocytopenia, hyperkalemia, and acidosis and a subsequent resection was required. A high output of intestinal juice from the jejunostomy caused severe hypovolemia and electrolyte imbalance with resultant death. Increased transverse abdominal area caused by marked intestinal dilatation, ascites, fetal distress, and hydrops fetalis may suggest an infarcted intestinal volvulus.

Effects of naftidrofuryl oxalate, a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus

We investigated the effects of age and nafidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-D-aspartate (NMDA), and gamma-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications.

Protective effects of a novel calcium antagonist with platelet-activating factor-antagonistic action, F-0401, against ischemic brain damage

The protective effects of a novel dihydropyridine calcium antagonist with platelet-activating factor-antagonistic action, F-0401, on ischemic brain damage were investigated using experimental ischemia models in rats and gerbils. F-0401 (1 and 10 mg/kg, i.p.) prevented increases in water content, determined by the wet-dry method, in ischemic areas 24 hr after 1 hr of middle cerebral artery occlusion in the rat. Pretreatment with F-0401 (1 and 10 mg/kg, i.p.) prevented extravasation of Evans blue dye in the brain following 2 hr of bilateral carotid artery occlusion and 2 hr of reperfusion in the rat. Pretreatment with F-0401 (1 and 10 mg/kg, i.p.) protected against neuronal damage to hippocampal CA1 pyramidal cells following 3 and 5 min of forebrain ischemia in the gerbil. Immunostaining against microtubule-associated protein-2 also demonstrated preservation of CA1 neurons in F-0401-treated animals. Thus, this study shows that F-0401 prevents the occurrence of brain edema, disruption of blood-brain barrier and neuronal damage caused by cerebral ischemia. The results demonstrate that F-0401 may be a powerful candidate as a therapeutic agent in the treatment of acute stroke in man.

Effects of naftidrofuryl oxalate, a 5-HT2 antagonist, on neuronal damage and local cerebral blood flow following transient cerebral ischemia in gerbils

Effects of naftidrofuryl oxalate (naftidrofuryl), a 5-HT2 antagonist, on neuronal damage and local cerebral blood flow was examined in a gerbil model of transient forebrain ischemia. Effect of ketanserin tartrate (ketanserin), another 5-HT2 antagonist, on neuronal damage was also examined. Pretreatment with naftidrofuryl or ketanserin prevented hippocampal CA1 neuronal loss after 5 min of transient ischemia. Naftidrofuryl did not improve hippocampal blood flow during and 1 h after transient ischemia determined by [14C]iodoantipyrine autoradiography but increased blood flow in the caudate-putamen 1 h after transient ischemia. The results show that: (1) the 5-HT2 antagonists protect against hippocampal CA1 neuronal damage; and (2) the protective effect of naftidrofuryl may not be caused by a hemodynamic mechanism but by a direct inhibitory neuromodulation via 5-HT2 antagonistic action.

Increased level/dose ratio of amphotericin-B in premature infants with renal failure

We introduced continuous intravenous infusion of amphotericin-B (AMPH-B) to extremely low birthweight (ELBW) infants (< 1000 g) with or without renal failure as a single agent for treating definite or probable systemic candidiasis. The species of Candida isolated from blood or tracheal aspirate or urine were C. albicans in seven infants, C glabrata in two, C. tropicalis in one and C. parapsilosis in one. The minimal inhibitory concentrations (MIC) of AMPH-B required against these isolates were less than 0.2 micrograms/mL except for that against one strain of C. albicans (0.78 microgram/mL). Serum AMPH-B levels were 0.31-0.78 (0.51 +/- 0.14) micrograms/mL when doses of 0.2-0.55 (0.32 +/- 0.11) mg/kg per day were being administered. The serum level was higher than the MIC of each isolate in all but one infant who died of disseminated intravascular coagulation and Candida pneumonia. Another infant died of congenital heart disease. The other nine infants survived. The serum level showed no correlation with the daily dose. The ratio of the serum level to the daily dose (L/D ratio) showed a significant correlation to serum creatinine (r = 0.787) and the linear regression curve followed the equation: L/D ratio = 0.223 x serum creatinine + 1.11 (P < 0.01). Few adverse effects due to AMPH-B were noted. Our data may give a simple reference to serum AMPH-B levels during continuous intravenous infusion from the dose and the serum creatinine level.

The possible involvement of tetrodotoxin-sensitive ion channels in ischemic neuronal damage in the rat hippocampus

To determine the role of tetrodotoxin-sensitive ion channels in post-ischemic selective neuronal death, the effect of tetrodotoxin on ischemia-induced brain cell injury was studied in rats. The animals were subjected to 20 min of cerebral ischemia in a four vessels occlusion model. Thirty min before ischemia, tetrodotoxin at a dose of 10(-7) or 10(-6) M was topically applied into the hippocampal CA1 subfield. Morphological changes in the CA1 subfield were evaluated 7 days after ischemia and compared with those of a vehicle-injected group. The average cell density of CA1 pyramidal neurons ipsilateral to the injection (cells/mm, mean +/- S.E.M.) was 27 +/- 7 (n = 6) in the vehicle-treated group, and 56 +/- 13 (n = 6) and 83 +/- 17 (n = 6) in the group treated with tetrodotoxin at doses of 10(-7) and 10(-6) M, respectively. Tetrodotoxin mitigated the ischemic hippocampal neuronal damage in a limited but dose-dependent manner. This suggests that activation of tetrodotoxin-sensitive ion channels might contribute to the process of the ischemic neuronal damage.

Rationale for frequency and dose of administration in gestrinone therapy for pelvic endometriosis in the experimental model of rabbit uterus

1. Gestrinone has been used for treatment of pelvic endometriosis, in doses of 2.5 mg twice a week. This study is designed to clarify it from the dynamics of sex steroid receptors in rabbit uterus. 2. Four different regimens were scheduled, namely daily 1 microgram estradiol-17 beta (E2, consistent with endogenous level of women) for 3 days, and together with either 30, 60 (consistent with 2.5 microgram of clinical dose) or 120 microgram(s) gestrinone, in single dose or with 20 microgram(s) gestrinone daily (divided dose in single 60 microgram(s) gestrinone administration) for 3 days. Receptors for estrogen (ER, type I and II) or progestin (PR) were determined by charcoal adsorption in cytosol and KCl extract, or sedimentation in non-KCl extractable fraction, using [3H]E2 or [3H]promegestone respectively. 3. Gestrinone decreased total ER (type I and II) levels, dose-dependently, except the case of 20 micrograms gestrinone daily in ER type II. Total ER type I level did not return to the pre-level until 3 days only after 120 microgram(s) gestrinone administration. Total ER type II level was decreasing in 3 days after 30, 60 or 120 micrograms gestrinone therapy. Total PR level was decreased in the order of strength: 120 micrograms gestrinone greater than 60 micrograms gestrinone greater than 30 microgram gestrinone greater than 20 micrograms gestrinone in group, and the recovery was not obtained until 72 hr only after 120 micrograms gestrinone therapy. The uterine weight was decreasing with the same strength in 3 days of the therapy independently upon the regimen. 4. In conclusion, gestrinone dose of 60 micrograms (2.5 mg of clinical dose) every 3 days is considered to be effective for anti-steroid action in sex steroid receptor dynamics in the rabbit uterus, contributing to the rationale for gestrinone treatment of pelvic endometriosis.

Inhibitory effect of polymyxin B on catecholamine secretion from cultured bovine adrenal medullary cells

Incubation of cultured bovine adrenal medullary cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), an activator of Ca2+/phospholipid-dependent protein kinase (protein kinase C), was associated with increased secretion of catecholamine (CA) from the cells. Polymyxin B (PMB, 30-300 microM), a preferential inhibitor of protein kinase C, inhibited the TPA-induced secretion of CA. PMB also inhibited CA secretion induced by other secretagogues, the Ca2+ ionophore ionomycin (10 microM), 56 mM K+ or acetylcholine (ACh). Ionomycin, 56 mM K+ or ACh increased the concentration of intracellular free Ca2+ ([Ca2+]i) (measured using the fluorescent calcium indicator quin2), whereas TPA did not increase [Ca2+]i. PMB blocked the increase in [Ca2+]i induced by 56 mM K+ or ACh at concentrations similar to those inhibiting the secretion of CA. In contrast, PMB did not affect ionomycin-induced increase in [Ca2+]i. These results strongly suggest that CA secretion induced by TPA or ionomycin is mediated via activation of protein kinase C. The results further indicate that in 56 mM K+- or ACh-evoked CA secretion, PMB inhibits the secretion by blocking Ca2+ influx into the cells.