[A new 3-dimensional head fixation device for brain imaging]

We have developed a new head fixation device for studies of brain function. This device was designed to immobilize subject's heads during image scanning and to precisely reproduce the head position for two different imaging modalities such as MRI and PET. The device consists of a plastic frame, a pillow filled with beads of styrene foam, and a face mask of thermoplastic resin which was originally intended for application in radiotherapy. A bridge for biting was incorporated into the mask for stable fixation. The device enables immobilization of subject's heads with good reproducibility of position at the practical level. Our results indicate that this head fixation system is useful for fixation of head during activation studies using PET.

Leukemia inhibitory factor (LIF) enhances trophoblast differentiation mediated by human chorionic gonadotropin (hCG)

We investigated the effect of LIF on the differentiation of trophoblasts. Isolated cytotrophoblasts were cultured with and without LIF and cell smears were immunocytochemically analyzed, using anti-hCG antibody. The percentage of differentiated trophoblasts stimulated by 10ng/ml of LIF was about 2.5-fold that in the control culture. The effect of LIF in inducing the differentiation of cytotrophoblasts to syncytiotrophoblasts was dose-dependent. The same effect was shown when hCG was added to the medium. This enhancing effect of LIF on trophoblast differentiation was blocked by adding anti-hCG antibody to the culture system. These results indicate that LIF enhanced trophoblast differentiation by stimulating hCG production in trophoblasts, and not by exerting a direct effect on the trophoblasts.

Non-X histiocytoma, similar to fibrous histiocytoma, in an infant

A case is presented of a female infant with an atypical histiocytoma. A gradually enlarging brown lesion was noted on the left side of the chest at the age of 2 weeks. Microscopic study of a biopsy revealed an ill-defined infiltration of spindle cells with indented nuclei. The tumor cells were positive for CD14, HLA-DR, lysozyme, alpha-1-antitrypsin and alpha-1-antichymotrypsin, and negative for CD1, CD3, CD8, CD10, CD19, CD68 and S-100 by immunohistochemistry. Electron microscopy demonstrated no distinct Birbeck's granules, but aberrant granules were seen in a small number of cells. At 7 months of age, a nodule with similar histologic features was noted in the nuchal region, but was incompletely resected. The patient remains recurrence-free at 36 months of age. This case is thought to be a benign form of non-X histiocytoma.

Interleukin-1 receptor antagonist expression in epithelial cells of human endometrium

OBJECTIVE

To examine the expression of interleukin-1 (IL-1) and IL-1 receptor antagonist (IL-1ra) in the human endometrium in the follicular and luteal phases.

METHODS

The concentrations of IL-1alpha and IL-1beta in the culture supernatants of endometrial cells were determined by enzyme-linked immunosorbent assay. Transcription of the IL-1ra gene in the endometrium was investigated by reverse polymerase chain reaction (PCR). Human endometrium was immunohistochemically stained using a monoclonal antibody specific to IL-1ra.

RESULTS

The concentrations of IL-1alpha and IL-1beta in the culture supernatants were 11 and 55 pg/ml, respectively, in the follicular phase, and 10 and 40 pg/ml, respectively, in the luteal phase. The concentration of IL-1ra was 465 pg/ml in the follicular phase and 1710 pg/ml in the luteal phase. Densitometric analysis of the reverse PCR products showed that the expression of IL-1ra mRNA was increased in endometrial cells in the luteal phase. Immunohistochemical staining revealed that epithelial cells were the main source of IL-1ra in human endometrium.

CONCLUSIONS

Human endometrial cells produce IL-1 (mainly IL-1beta) and IL-1ra. The level of IL-1ra production in human endometrial epithelial cells was greater in the luteal phase than in the follicular phase due to the increased transcription of the IL-1ra gene.

[Usefulness of adjuvant chemotherapy with antimetabolites for cervical invasive cancer]

A series of 584 patients with cervical invasive cancer were included in the retrospective study on the efficacy of long-term oral maintenance chemotherapy with antimetabolites (Fluorouracil or Tegaful). The patients were histologically classified into the squamous cell carcinoma (SCC) group and the adenocarcinoma (AD) group. In the SCC group (n = 518), 163 patients were given more than 300 mg/day of antimetabolite tablets for one year or more after the main therapy (hysterectomy or pelvic irradiation). In the AD group (n = 66), 36 patients were treated with the same dose of antimetabolites. The Kaplan-Meier overall and cancer specific survival analysis estimates that the chronic administration of antimetabolites did not improve the cumulative 5-year survival in the SCC group. In contrast, the cumulative 5-year survival rate in the AD group treated with antimetabolites (88%) was significantly higher than that without chemotherapy (64%) by Kaplan-Meier analysis. This significant improvement in the survival rate in the AD group due to antimetabolites was notable in patients in FIGO stage I or II treated with radical or semiradical hysterectomy, these results indicate that oral adjuvant chemotherapy with antimetabolites is useful for cervical adenocarcinoma, but not for squamous cell carcinoma.

Activity in the human primary motor cortex related to arm and finger movements

With the purpose of mapping representations of the finger and proximal arm in the human primary motor cortex (MI), we measured regional cerebral blood flow (rCBF) in eight right-handed normal volunteers during self-paced finger and proximal arm movements. Each movement activated two different fields in MI, one located deep in the anterior lip of the central sulcus and the other relatively close to the surface of the precentral gyrus. Arm fields were located higher than finger fields. A superficial arm field and a deep finger field partially, overlapped. The results indicate that there are two spatially separate motor representations of the finger and proximal arm in the human MI.

[Clinical usefulness of 201Tl-chloride scintigraphy for the diagnosis of bone metastases]

Fifty-five patients with bone lesions underwent 201Tl-chloride (201TlCl) scintigraphy to evaluate its findings and usefulness for the diagnosis of bone metastases. 201TlCl scintigraphy was performed 15 minutes (early scan) and 2 hours (delayed scan) after intravenous administration of 5.55 MBq/kg of 201Tl-chloride. To evaluate the degree of tracer retention at the lesions, we calculated retention index after setting regions of interest in each lesions demonstrated tracer uptake in both early and delayed scans. Among 118 lesions of pathologically and/or clinically confirmed bone metastases, 201TlCl planar images disclosed 90 (76.3%) and 88% (74.6%) lesions on early and delayed scans, respectively. SPECT images were preferable for the evaluation of the lesions in the spine, the thoracic cage and pelvis. Correlation of tumor size with findings on 201TlCl images demonstrated 90.5% sensitivity for the metastases more than 7 cm3. No correlational difference was seen in the sensitivity depending on primary cancers. The overall retention index of bone metastases was -21.4 +/- 47.1. Bone metastases of pulmonary adenocarcinomas and small cell carcinomas demonstrated higher retention index than those of pulmonary squamous cell carcinomas and breast cancers. On 201TlCl images, no abnormal tracer uptakes were seen in benign lesions detected by 99mTc-hydroxymethylene diphosphonate (99mTc-HMDP) images except 5 lesions. The retention index of these benign lesions demonstrated abnormal uptakes on 201TlCl images was -48.3 +/- 15.0, which found no significant difference between that of metastases. In cases of vertebral compression fractures, abnormal tracer uptakes were demonstrated in 9 of the 12 pathologic fractures against 2 of the 10 benign ones. Those 2 benign fractures proved to be vertebral tuberculosis.(ABSTRACT TRUNCATED AT 250 WORDS)

[A correlative study of the aluminum content and aging changes of the brain in non-demented elderly subjects]

The interrelation of the aluminum content and aging change of the nerve cells was studied with special reference to the neurofibrillary tangle (NFT) and occurrence of senile plaque (SP), in 15 autopsied brains (cerebrum) of non-demented elderly subjects varying in age from 75 to 101 years old and 10 cases of non-demented non-elderly adult subjects. 1) In the brain of non-demented non-elderly adult subjects, the aluminum content of the hippocampus was 14.4 +/- 1.39 ppb and that of the cortex of the frontal lobe was 20.4 +/- 2.54 ppb. In the brain of the non-demented elderly subjects, the aluminum content of the hippocampus was 401.7 +/- 60.05 ppb and that of the cortex of the frontal lobe was 373.29 +/- 72.35 ppb. Comparison of the two groups showed obviously higher levels in the latter group, being 28 times in the hippocampus and 19 times in the cortex of the frontal lobe. 2) The histochemical demonstration of the aluminum localization by the Morin method disclosed the positive fluorescence reaction along the part of the disintegrating neurofibrillary tangle and amyloid core in the senile plaques of non-demented elderly subjects. In the normal brain tissue, positive fluorescence reaction was observed in the wall of the capillary vessels of the blood brain barrier, perivascular glial supporting tissues, the nuclei of the astrocytes and nuclei, nucleoli of the nerve cells partially. No fluorescence reaction was observed in the non-demented adult subjects. 3) Morphologically, the appearance of the neurofibrillary tangle was noted in some cases of non-demented elderly group with higher aluminum levels. Classical and diffuse type senile plaques were dispersed in the 1st to 4th zone of the cortex of the frontal lobe. However, diffuse type senile plaques in the hippocampus appeared to a lesser extent. Neurofibrillary tangles were slightly noted in the cortex of the frontal lobe, however marked increase was confirmed in the CA1 to CA3 zones of the hippocampus. Ultrastructurally, paired helical filaments (PHF) were noted in the neurofibrillary tangle constituent and the increase of amyloid fibrils in senile plaques was confirmed. In this study, high levels of the aluminum content of the brain were confirmed in the non-demented elderly subjects. Moreover, the histochemical demonstration of aluminum localization by the Morin method disclosed a positive fluorescence reaction along the sites of neurofibrillary tangles and amyloid core in the senile plaques of non-demented elderly subjects.(ABSTRACT TRUNCATED AT 400 WORDS)

[A simple method for measurement of cerebral blood flow using 123I-IMP SPECT with calibrated standard input function by one point blood sampling; validation of calibration by one point venous blood sampling as a substitute for arterial blood sampling]

In a simplified method for measurement of cerebral blood flow using one 123I-IMP SPECT scan and one point arterial blood sampling (Autoradiography method), input function is obtained by calibrating a standard input function by one point arterial blood sampling. A purpose of this study is validation of calibration by one point venous blood sampling as a substitute for one point arterial blood sampling. After intravenous infusion of 123I-IMP, frequent arterial and venous blood sampling were simultaneously performed on 12 patients of CNS disease without any heart and lung disease and 5 normal volunteers. The radioactivity ratio of venous whole blood which obtained from cutaneous cubital vein to arterial whole blood were 0.76 +/- 0.08, 0.80 +/- 0.05, 0.81 +/- 0.06, 0.83 +/- 0.11 at 10, 20, 30, 50 min after 123I-IMP infusion, respectively. The venous blood radioactivities were always 20% lower than those of arterial blood radioactivity during 50 min. However, the ratio which obtained from cutaneous dorsal hand vein to artery were 0.93 +/- 0.02, 0.94 +/- 0.05, 0.98 +/- 0.04, 0.98 +/- 0.03, at 10, 20, 30, 50 min after 123I-IMP infusion, respectively. The venous blood radioactivity was consistent with artery. These indicate that arterio-venous difference of radioactivity in a peripheral cutaneous vein like a dorsal hand vein is minimal due to arteriovenous shunt in palm. Therefore, a substitution by blood sampling from cutaneous dorsal hand vein for artery will be possible. Optimized time for venous blood sampling evaluated by error analysis was 20 min after 123I-IMP infusion, which is 10 min later than that of arterial blood sampling.

Detection of high-risk human papillomavirus in the cervix and semen of sex partners

To investigate the possibility of sexual transmission of human papillomavirus (HPV), 53 married couples were examined for the presence of HPV-16 and -18 DNAs in the uterine cervix and semen using the polymerase chain reaction method. Twenty-three of the 53 women and 12 of the 53 male partners were positive for HPV-16 DNA. No HPV-18 DNA was detected in samples from any of the partners. In 27 pairs, both partners were negative for HPV DNA in cervix or semen; in the remaining 26 pairs, at least 1 of the partners was HPV-16-positive. In 9 (35%) of these 26 pairs, both partners were infected. Furthermore, 9 (75%) of the 12 women with HPV-positive partners were HPV-positive, while 9 (39%) of the 23 men with HPV-positive female partners were HPV-positive. These findings suggest an increased risk of HPV transmission via sexual intercourse, thereby underscoring the importance of preventive care against HPV infection during intercourse.

Density-associated changes in platelet-activating factor acetylhydrolase activity and membrane fluidity of human erythrocytes

Platelet-activating factor acetylhydrolase is known to degrade oxidatively fragmented phospholipids which are similar in structure to platelet-activating factor. We examined changes of acetylhydrolase activity during in vivo aging of human erythrocytes and tried to assess its role in maintaining the membrane properties of erythrocytes. Higher-density erythrocytes are enriched with older cells. Erythrocytes obtained from seven healthy colleagues were separated into four density fractions by centrifugation in discontinuous Percoll density gradients. Both membrane and cytosolic acetylhydrolase decreased with increasing erythrocyte density. Membrane and cytosolic acetylhydrolase activities in the lightest fraction were 2.0 +/- 1.0 (SD) nkat/g protein and 362 +/- 58 pkat/g protein, respectively, and these values were significantly higher than those in the densest fraction: 1.3 +/- 0.7 nkat/g protein and 286 +/- 70 pkat/g protein, respectively. Membrane acyltransferase activity also decreased with red cell density and the average values in the lightest and densest fractions were 51.2 +/- 23.6 and 27.0 +/- 20.2 mukat/g protein, respectively. Generation of thiobarbituric acid-reactive substances induced by t-butyl hydroperoxide treatment decreased with increasing cell density, and the inhibition of acetylhydrolase with diisopropylfluorophosphate resulted in enhanced peroxide-induced lipid oxidation, particularly in lower-density fractions. There was no significant change in basal levels of thiobarbituric acid-reactive substances in red cell membrane. Membrane fluidity was evaluated by fluorescence recovery after photo-bleaching and it decreased as erythrocyte density increased. We conclude that the activity of the deacylation/reacylation cycle maintained by acetylhydrolase and acyltransferase is gradually reduced during in vivo aging of erythrocytes. This may be connected with decreases of polyunsaturated fatty acids and membrane fluidity in old erythrocytes.

Enhanced delivery and antitumor activity of doxorubicin using long-circulating thermosensitive liposomes containing amphipathic polyethylene glycol in combination with local hyperthermia

Enhanced delivery of doxorubicin (DXR) to a solid tumor subjected to local hyperthermia was achieved by using long-circulating, thermosensitive liposomes (TSL) composed of dipalmitoyl phosphatidylcholine (DPPC)/distearoyl phosphatidylcholine (DSPC) (9:1, m/m) and 3 mol% amphipathic polyethylene glycol (PEG) in colon 26-bearing mice. Inclusion of 3 mol% of distearoyl phosphatidylethanolamine derivatives of PEG (DSPE-PEG, amphipathic PEG) with a mean molecular weight of 1000 or 5000 in DPPC/DSPC liposomes resulted in decreased reticuloendothelial system (RES) uptake and a concomitant prolongation of circulation time, affording sustained increased blood levels of the liposomes. Concomitantly, DXR levels in blood were also kept high over a long period. The presence of amphipathic PEG did not interfere with the encapsulation of DXR by the pH gradient method (> 90% trapping efficiency) or with the temperature-dependent drug release from the liposomes. The optimal size of these liposomes was 180-200 nm in mean diameter for thermosensitive drug release and prolonged circulation time. The DXR levels in the tumor after injection of long-circulating TSL (DXR-PEG1000TSL or DXR-PEG5000TSL, at a dose of 5 mg DXR/kg) with local hyperthermia were much higher than after treatment with DXR-TSL lacking PEG or with free DXR, reaching 7.0-8.5 DXR micrograms/g tumor (approximately 2 times or 6 times higher than that of DXR-TSL or free DXR, respectively). Furthermore, the combination of DXR-PEGTSL and hyperthermia effectively retarded tumor growth and increased survival time.(ABSTRACT TRUNCATED AT 250 WORDS)

Current topic: human placental Fc receptors

Human immunoglobulin G (IgG) Fc receptors are important in the materno-fetal relationship. Three classes of IgG Fc receptors are recognized which generate multiple isoforms, most of which are expressed in different cellular components of human placenta at different times during pregnancy. Although the distinct biological functions of Fc gamma R phenotypes expressed in human placenta are still unknown, recent data provide evidence for an important association between the Fc gamma R phenotype and transcytosis of IgG in the placenta. Selective transfer of maternal IgG across the placenta provides passive immunity to the fetus during the period when its own immune system is gaining protective potential. Furthermore, placenta-specific macrophages may contribute through Fc gamma R-mediated phagocytosis to the protection of the fetus from either infection or maternal immune attack against paternally inherited fetal antigens. Ontogeny and expression of various isoforms of Fc gamma R subtypes may be the key to the elucidation of the transport mechanism of maternal IgG to the fetus, in addition to the determination of the mechanisms of placental protection of the fetus against the maternal immune system.

[The studies on the mechanism of platelet activation induced by exogenous arachidonic acid with special reference to intraplatelet Ca2+ mobilization]

It has been reported that the dose-response curves for exogenous arachidonic acid (AA)-induced human platelet aggregation and secretion are biphasic. Low concentration (0.5-10 microM) and high concentration (30 microM-50 microM) of AA increase both platelet aggregation and secretion. In contrast, middle concentration (10 microM-20 microM) of AA reduces the both phenomena. This mechanism, however, has not been elucidated in detail. Since calcium ion has been reported to act as an important second messenger for platelet activation, intracellular Ca2+ concentration ([Ca2+]cyt) using fura-2 and aequorin, the plasma membrane-bound Ca2+ using chlortetracycline(CTC), and Ca2+ flux across the plasma membrane using 45Ca2+, in human platelet suspensions were measured in the presence and/or in the absence of external Ca2+. Cyclic AMP, inhibitory substance of platelet activation, was also measured. The increase of [Ca2+]cyt induced by low concentration of AA was mainly derived from intracellular Ca2+ storage site via thromboxane A2-phospholipase C and the increase of [Ca2+]cyt induced by high concentration of AA was mainly derived from both membrane bound Ca2+ and influx of extracellular Ca2+. The membrane bound Ca2+ release was induced by the direct effect to the plasma membrane of AA in a dose dependent manner, and it was suggested that CTC molecules were not bound to the cytoplasmic organella membrane but only to the plasma membrane. [Ca2+]cyt measured using aequorin method was thought to reflect the change in the concentration of Ca2+ area directory under the plasma membrane. The time course of intracellular 45Ca2+ flux suggested that the plasma membrane Ca2+ pump might operate in AA-stimulated platelets. Inhibition of increase of [Ca2+]cyt, and the decrease of platelet aggregation observed in 10-20 microM AA stimulation were related to the increase of cyclic AMP level. These results support the clinical usefulness of drugs that increase the cyclic AMP level in platelet.

Pyrazolopyridine derivative acts as a novel cyclooxygenase inhibitor: antiplatelet effect in aged patients with ischemic stroke

OBJECTIVE

To examine the antiplatelet effect of a novel pyrazolopyridine derivative (KC-764) in geriatric patients with ischemic stroke.

DESIGN

Randomized clinical trial of three graded dose levels.

SETTING

A geriatric clinic attached to a nursing home.

PATIENTS

Fifteen patients with a history of cerebral infarction with a mean age of 75 +/- 5 years (range, 65-83). Patients were divided into three groups and administered 10, 20, or 40 mg/day KC-764 for 8 weeks.

MEASUREMENTS

Platelet aggregation induced by arachidonate, ADP, collagen and platelet-activating factor. Plasma or serum levels of thromboxane B2 and 6-ketoprostaglandin F1 alpha.

MAIN RESULTS

Platelet aggregation was inhibited by KC-764 administration and returned to the control level after discontinuation. Although plasma thromboxane B2 levels were markedly decreased, plasma 6-ketoprostaglandin F1 alpha was not affected. However, the dose of 10 mg/day was not sufficient to maintain an effective plasma level of KC-764. There were no side effects or changes in laboratory findings.

CONCLUSIONS

We confirmed that KC-764 at a dose of 20 to 40 mg/day is an effective antiplatelet agent and a good candidate for a trial to see if it is feasible for long-term use for the prevention of ischemic stroke in high-risk patients.

Loss of biological activity of human chorionic gonadotropin (hCG) by the amino acid substitution on the "CMGCC" region of the alpha-subunit

In order to study the bioactive sites of the glycoprotein hormones, we have prepared five point mutants on the CMGCC (Cys28-Met29-Gly30-Cys31-Cys32) region of the human alpha-subunit by using site-directed mutagenesis. Each mutant human chorionic gonadotropin (hCG) agr; cDNA and a wild-type hCG beta cDNA were transcribed by T3 RNA polymerase, and the mixture of the hCG alpha mRNA and hCG beta mRNA was microinjected into Xenopus laevis oocytes. All five mutant hCGs produced in oocyte culture supernatants were detected as immunoreactive forms by enzyme immunoassay. In contrast, four mutants (Cys28-->Tyr28, Gly30-->Arg30, Ala30, Asp30) were devoid of biological activity in vitro bioassay using the production of testosterone with mouse Leydig cells. These results indicate that the CMGCC region in the alpha-subunit, particularly the cysteine residue at position 28 and the glycine residue at position 30, plays an important role in the biosynthesis of glycoprotein hormones.

A Clostridium perfringens vector for the selection of promoters

A promoter selection vector for Clostridium perfringens genes was constructed from a C. perfringens-Escherichia coli shuttle vector, pJIR418. The plasmid carries a promoterless chloramphenicol acetyltransferase gene (catP), derived from pIP401, downstream of the multiple cloning sites of pUC18. When a promoter region of the phospholipase C gene was inserted into one of the cloning sites, derivatives of C. perfringens strain 13 carrying the resultant plasmid acquired resistance to chloramphenicol. This plasmid should be useful reporter system for C. perfringens genes.

Pharmacological characteristics of hyperambulation induced by the sigma ligand (+)-3-PPP in rats

(+)-3-(3-Hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP), a sigma ligand, at doses above 3 mg/kg (s.c.) increased the ambulatory activity of rats, while the (-) isomer of 3-PPP with low affinity for sigma receptors, did not significantly modify the ambulatory activity at 10 and 30 mg/kg (s.c.). The ambulation-increasing effect of (+)-3-PPP was prevented by the sigma receptor antagonists BMY 14802 and rimcazole or the sigma/dopamine D2 antagonist haloperidol. The (+)-3-PPP effect was also attenuated by pretreatment with the monoamine depletor reserpine or the tyrosine hydroxylase inhibitor alpha-methyltyrosine, but was not affected by the tryptophan hydroxylase inhibitor p-chlorophenylalanine. Moreover, the (+)-3-PPP effect was antagonized by the dopamine D2 antagonist sulpiride, whereas pretreatment with the 5-HT1A agonist 8-OH-DPAT and the alpha-adrenoceptor antagonist phenoxybenzamine did not exert any significant effect. These results indicate that sigma receptors are involved in the neuronal mechanism(s) of hyperambulation induced by (+)-3-PPP, and the sigma system may exert both a presynaptic action and a dopamine D2 receptor-mediated action to increase the central dopaminergic function.

PF1018, a novel insecticidal compound produced by Humicola sp

A new insecticidal compound PF1018 was isolated from the culture broth of Humicola sp. It exhibited insecticidal activity against a wide range of critical pest species. The structure of PF1018 was determined to be (7aS)-2-((2E)-1-hydroxy-3-((1S,3aR,4R,5R,7aR)-3a,4,5,7 a-tetrahydro-1,3,5,7- tetramethyl-5,1-((3S)-(Z)-2,3-dimethylpropeno)-1H-inden-4-yl )-2- propenylidene)pyrrolizidine-1,3-dione, by NMR spectral analyses coupled with X-ray crystallographic analysis and chemical degradation study.