Cis-urocanic acid attenuates histamine receptor-mediated activation of adenylate cyclase and increase in intracellular Ca2+

UVB irradiation causes suppression of delayed hypersensitivity. Various photoreceptors and mediators of these changes have been proposed, one of which is cis-urocanic acid formed from the naturally occurring trans-urocanic acid in the epidermis on exposure to UV irradiation. The mechanism by which cis-urocanic acid alters the immune system is not fully clarified, but it acts through different mechanisms, perhaps via histamine or histamine-like receptors. Histamine stimulation of keratinocytes induces activation of adenylate cyclase leading to an accumulation of cyclic AMP and an increase in intracellular Ca2+. Thus we investigated the effects of cis-urocanic acid on these transmembrane signaling systems in keratinocytes. Normal human keratinocytes were cultured in serum-free KGM medium. Cyclic AMP was measured by radioimmunoassay. Alterations in intracellular Ca2+ in single living keratinocytes were measured using an inverted fluorescence microscope and an ARGUS-200/CA digital imaging system. Cis-urocanic acid itself did not induce adenylate cyclase activation in cultured normal human keratinocytes. Cis-urocanic acid inhibited histamine-induced cyclic AMP accumulation. It did not affect keratinocyte growth, and did not induce an increase in intracellular Ca2+, but did attenuate the histamine-induced increase in intracellular Ca2+ but not that induced by epinephrine. Cis-urocanic acid acts on keratinocytes via modulation of the effects of histamine.

[Telomerase activity in esophageal carcinoma and lesions unstained with Lugol's solution]

Telomerase is a specific enzyme required for the replication of telomeres. Its activity is detected in almost human cancers. We examined in esophageal carcinoma and lesions unstained with Lugol's solution telomerase activity by using telomeric repeat amplification protocol (TRAP) assay. Telomerase activity was detected in all 22 esophageal carcinomas, regardless of histopathological findings. In unstained lesions, telomerase activity was detected in 15 of 22; 10 squamous cell carcinomas, four dysplasia, one regenerative epithelium, no telomerase activity was found in seven; four normal esophageal epithelia, two Barrett's esophagi, one regenerative epithelium. These results suggest that telomerase activity may be a useful molecular marker for the diagnosis of esophageal carcinoma and of the early esophageal carcinoma in area unstained with Lugol's solution.

[Spinal cord stimulation therapy at an early stage for unresponsive patients with hypoxic encephalopathy]

Recently, spinal cord stimulation (SCS) has been used for the treatment of patients in prolonged coma. However, the results of SCS in unresponsive patients with hypoxic encephalopathy at the chronic stage have not been satisfactory. Considering these circumstances, we began SCS from one month after the onset of hypoxic encephalopathy and evaluated its effect. Twelve patients (5 males and 7 females) with hypoxic encephalopathy, ranging in age from 7 to 72 years, were treated with SCS. The causes of hypoxia were acute cardiac failure in 4, automobile exhaust gas poisoning in 2, and asthma, pneumothorax, anaphylaxis, asphyxia, drowning and hypotension during aortic surgery in one patient each. One month after the onset, an electrode for electrical stimulation was implanted in the epidural space at the C2-C4 level under general anesthesia. The spinal cord was stimulated for 8 hours each day, starting on the day after implantation, and was continued for 3 months. Magnetic resonance imaging (MRI), cerebral blood flow (CBF) measurement using xenon-computed tomography (Xe-CT), and measurement of auditory evoked potential (AEP) and somatosensory evoked potential (SEP) were carried out 3 weeks after the onset for presurgical evaluation. Among the 12 patients, 7 (58%) showed clinical improvement, beginning within two weeks after starting stimulation. They were able to communicate with others and to express their emotion. However, disturbance of writing, picture drawing and calculation were not improved by stimulation. From presurgical evaluation, cases in which SCS therapy was effective had the following features: 1) No hemorrhagic infarction in the basal ganglia was demonstrable by MRI. 2) Mean hemispheric CBF measured by the Xe-CT method exceeded 25 ml/100 g per min. 3) The mean increase in hemispheric CBF 20 min after acetazolamide administration exceeded 5 ml/100 g per min. 4) An N20 peak was evident on the median nerve SEP, SCS appears to be an effective supplementary for unresponsive patients with hypoxic encephalopathy at the subacute stage, in addition to rehabilitation and drug therapy.

Cerebral blood volume in the sleep measured by near-infrared spectroscopy

We investigated the relationship between hemodynamic changes in the cortex measured by near-infrared spectroscopy (NIRS) and the polysomnographic changes during sleep. Four healthy male volunteers participated in the study. Near-infrared spectroscopy measuring and polysomnographic recordings were done simultaneously during sleep. In many case, oxy-hemoglobin (oxy-Hb) decreased and deoxy-hemoglobin (deoxy-Hb) increased during the transition from wakefulness to sleep, and oxy-Hb increased toward deep sleep. Oxy-Hb and deoxy-Hb had larger fluctuations during REM sleep than those during non-REM sleep. During REM sleep, oxy-Hb often showed a lower level and deoxy-Hb showed a higher level than those during the preceding and following non-REM sleep.

Nodular localized cutaneous amyloidosis: further demonstration of monoclonality of infiltrating plasma cells in four additional Japanese patients

Nodular localized cutaneous amyloidosis (NLCA) is a disorder characterized by deposition of amyloid derived from immunoglobulin light chains. We used semi-nested polymerase chain reaction (PCR) to analyse archival paraffin-embedded sections from a previous patient and from four additional, previously reported patients with NLCA to determine whether involvement of monoclonal plasma cells is a universal feature of this condition. The semi-nested PCR analysis revealed one or two amplified bands, around 100-120 bp, for all five cases of NLCA, although the yields varied from case to case. These results suggest that clonal expansion of plasma cells in NLCA may occur locally.

Validation of transgenic mice carrying the human prototype c-Ha-ras gene as a bioassay model for rapid carcinogenicity testing

Carcinogenicity testing is indispensable for identifying environmental carcinogens and for evaluating the safety of drugs in the process of development. Conventional 2-year rodent bioassays are one of the most resource-consuming tests in terms of animals, time, and costs. Development of rapid carcinogenicity testing systems that can assess carcinogenicity within a short period has become a social demand and is essential to improve efficacy in the identification of environmental carcinogens as well as in the development of new drugs. In this review we introduce the rapid carcinogenicity testing system using transgenic (Tg) mice carrying the human prototype c-Ha-ras gene, namely rasH2 mouse (CB6F1-TgHras2 mouse is the same mouse). The studies have been conducted to validate the rasH2 mouse as a model for the rapid carcinogenicity testing system. Our current validation studies revealed that rasH2 mice are able to detect various types of mutagenic carcinogens within 6 months. The rasH2 mice may also be able to detect various nonmutagenic carcinogens. The validation studies also revealed that rasH2 mice are generally much more susceptible to both mutagenic and nonmutagenic carcinogens than control non-Tg mice. No significant tumor induction has been observed in rasH2 mice with either mutagenic or nonmutagenic noncarcinogens. More rapid onset and higher incidence of more malignant tumors can be expected with a high probability after treatment with various carcinogens in the rasH2 mice than in control non-Tg mice. The rasH2 mouse appears to be a promising candidate as an animal model for development of a rapid carcinogenicity testing system.

Immunohistochemical analysis of TrkA neurotrophin receptor expression in human non-neuronal carcinomas

The Trk family of tyrosine protein kinase receptors plays a significant role in the development and maintenance of neural tissues. It has been recently shown that Trk receptors are also expressed by a wide range of normal non-neuronal tissues in humans in a cell type-specific manner. In the present study, the expression patterns of TrkA in 337 non-neuronal invasive carcinomas of 15 different human tissues were investigated immunohistochemically. Overall, 133 (39%), 101 (30%) and 103 (31%) tumors exhibited strong, moderate and no TrkA immunoreactivity, respectively. Esophageal and thyroid carcinomas expressed high levels of TrkA, whereas the levels in gastric and colon cancers were low. TrkA expression was detected not only in carcinomas originating from TrkA-positive normal counterpart tissues, including the esophagus, breast, lung and uterus, but also in those from TrkA-negative tissues/cells of the thyroid, liver and ovary. Immunostaining for nerve growth factor-beta, the specific ligand for TrkA, in esophageal and breast carcinomas demonstrated its immunoreactivity in stromal fibroblasts and some TrkA-expressing tumor cells. These results suggest that paracrine/autocrine regulation via stromal/tumoral NGF-tumoral TrkA interaction may be involved in the growth of certain non-neuronal carcinomas.

MEG covariance difference analysis: a method to extract target source activities by using task and control measurements

A method is proposed for extracting target dipolesource activities from two sets of evoked magnetoencephalographic (MEG) data, one measured using task stimuli and the other using control stimuli. The difference matrix between the two covariance matrices obtained from these two measurements is calculated, and a procedure similar to the MEG-multiple signal classification (MUSIC) algorithm is applied to this difference matrix to extract the target dipole-source configuration. This configuration corresponds to the source-configuration difference between the two measurements. Computer simulation verified the validity of the proposed method. The method was applied to actual evoked-field data obtained from simulated task-and-control experiments. In these measurements, a combination of auditory and somatosensory stimuli was used as the task stimulus and the somatosensory stimulus alone was used as the control stimulus. The proposed covariance difference analysis successfully extracted the target auditory source and eliminated the disturbance from the somatosensory sources.

[Selective extraction of organotin from biological sample by supercritical fluid extraction]

The preliminary separation and concentration of organotin compounds from the matrix of biological samples is necessary, due to the very low content of organotin and the fat included in samples will largely interfere the analysis of organotins. In this work, supercritical fluid extraction (SFE) for the preliminary separation and concentration of organotin has been studied. Pure CO2 was used as mobile phase. The extractives can be used to supercritical fluid chromatographic (SFC) analysis of organotins. The model sample was prepared by adding diphenyltin (DPT) to soya powder. The effects of the pressure and temperature on SFE were investigated. A small amount of fat was also extracted together with organotins. Extract was injected into SFC system, in which a Kapcell Pak ODS column was used for separation of organotin and fat. The effect of pressure on the extraction percentage of DPT and fat was investigated at 40 degrees C. At lower pressure (10-15 MPa), a maximum extraction efficiency (63%) was attained for DPT, while the fat is extracted only 28.3%. The increase in temperature is advantageous for the selective extraction of DPT. However, the extraction efficiency of DPT decreased as the extraction temperature was increased. When a lower pressure (10 MPa) and a higher temperature (50 degrees C) were used, the organotin (DPT) was extracted up to a maximum (59.9%) within 30 min, while fat was extracted only 4.9%.

1,25-Dihydroxyvitamin D3 and a new analogue, 22-oxacalcitriol, modulate proliferation and interleukin-8 secretion of normal human keratinocytes

Vitamin D3 is a new therapeutic agent for psoriasis. Hyperproliferation of epidermis and over-secretion of IL-8 by keratinocytes are the characteristic features of psoriasis. The present study was conducted to determine whether a new vitamin D3 analogue, 22-oxacalcitriol, could be effective in inhibiting the proliferation and IL-8 secretion of normal human epidermal keratinocytes. Cell proliferation was measured colorimetrically by the MTS assay. IL-8 secretion was measured with ELISA. Proliferation of cultured normal human epidermal keratinocytes was inhibited in the presence of 1,25-dihydroxyvitamin D3 at the concentrations of 1 x 10(-8) to 1 x 10(-6) M and 22-oxacalcitriol at concentrations of more than 1 x 10(-9) M at 48 h. IL-8 secretion from normal human epidermal keratinocytes was augmented by TNF-alpha, or synergistically by TNF-alpha and IFN-gamma. 1,25-Dihydroxyvitamin D3 and 22-oxacalcitriol inhibited cytokine-stimulated IL-8 production dose dependently after 24 h incubation without inhibition of cell proliferation. 1,25-Dihydroxyvitamin D3 and 22-oxacalcitriol are considered to inhibit the proliferation of keratinocytes directly and indirectly with inhibition of the secretion of IL-8 from keratinocytes. The inhibition of IL-8 secretion from keratinocytes by vitamin D3 could modulate the behaviour of immunocompetent cells infiltrating in the skin.

Noise covariance incorporated MEG-MUSIC algorithm: a method for multiple-dipole estimation tolerant of the influence of background brain activity

This paper proposes a method of localizing multiple current dipoles from spatio-temporal biomagnetic data. The method is based on the multiple signal classification (MUSIC) algorithm and is tolerant of the influence of background brain activity. In this method, the noise covariance matrix is estimated using a portion of the data that contains noise, but does not contain any signal information. Then, a modified noise subspace projector is formed using the generalized eigenvectors of the noise and measured-data covariance matrices. The MUSIC localizer is calculated using this noise subspace projector and the noise covariance matrix. The results from a computer simulation have verified the effectiveness of the method. The method was then applied to source estimation for auditory-evoked fields elicited by syllable speech sounds. The results strongly suggest the method's effectiveness in removing the influence of background activity.

[Neoadjuvant chemotherapy and concurrent radiochemotherapy for advanced esophageal carcinoma potentially invading adjacent structures]

Advanced esophageal carcinoma invades adjacent structures, and its resection without residual tumor is difficult. Preoperative chemotherapy and combined modality therapy are being tried to improve survival in patients with T4 esophageal carcinoma. For these cases, chemotherapy with 5-fluorouracil and cisplatin (FP) is known to be not so effective. For 17 patients with T4 esophageal carcinoma in 2 institutes, treated primarily with chemotherapy with 5-fluorouracil, cisplatin and adriamycin (FAP), the response rate was 76%. Operation was performed in all of them after 2-3 courses of FAP, and curative resection without resection of adjacent structure was carried out in 14 cases (82%). Treatment with FP concurrent with more than 50Gy of radiation (CRT) was effective for patients with T4 esophageal carcinoma, its response rate was 72.80% in Japanese literature, and resectability rate was 37-48% after treatment. All of our 3 cases had partial response, but resection was not performed because patients refused surgery. Phase II trial of neoadjuvant chemotherapy followed by concurrent chemotherapy plus high-dose radiation therapy was carried out for 45 patients with clinical stage T1-4N0-1M0 in an attempt to improve the result of concurrent chemoradiation in America (RTOG), and the overall median survival was 20 months. But this treatment will not be used, because treatment-related death was seen in 10%. We think that FAP and CRT are the most effective neoadjuvant therapy in patients with T4 esophageal carcinoma. If curative resection is possible after treatment, operation should be done to improve prognosis.

[Functional MRI using interleaved EPI]

One of main purposes of functional MRI is to identify functional map on human brain. We considered spatial resolution was a important factor and investigated influences of it on signal changes and activated region size. Functional images were acquired with Echo-Planar imaging (EPI) and interleaved EPI (IEPI). IEPI is superior in spatial resolution but inferior in signal to noise ratio (SNR) to EPI. As a result of Student's t-test analysis, activated region sizes of IEPI reduced to less than half those of EPI while IEPI had larger signal increase than EPI. We confirmed that the reduction was caused by low SNR and our estimation analysis could prevent it.

Rescue by cytokines of apoptotic cell death induced by IL-2 deprivation of human antigen-specific T cell clones

The control of cell survival and cell death is of central importance in tissues with high cell turnover such as the lymphoid system. We have examined the effect of cytokines on IL-2 deprivation-induced apoptosis of human antigen-specific T helper clones with different cytokine production profiles. We found that IL-2, interferon-alpha (IFN-alpha), and IFN-beta inhibited IL-2 deprivation apoptosis in Th0, Th1, and Th2 clones. We also found that IL-2 protects T cell clones from IL-2 deprivation apoptosis accompanying active proliferation and enhanced expression of P53, Rb and Bcl-xL proteins. In contrast, IFN-alpha/beta rescued T cell clones from apoptosis without active proliferation, and expression of apoptosis-associated proteins tested so far was unaffected. This may be due to the fact that T cells treated with IL-2 contained those located in S + G2/M phases of the cell cycle, whereas the vast majority of T cells treated with IFN-alpha/beta were located in G0/G1 phase. IFN-alpha/beta specifically induced tyrosine phosphorylation and translocation into nucleus of signal transducers and activators of transcription (STAT) 2 protein in the T cell clones. In addition, over-expression of STAT2 by transfection of the cDNA prevented apoptosis of the T cell clones. Our present study shows that IFN-alpha and -beta mediate anti-apoptotic effect through other pathways than that of IL-2 in growth factor deprivation apoptosis.

[High performance liquid chromatographic determination of reducing sugars in fruit juices with laser resonance Raman detection]

A liquid chromatographic method using semi-microcolumn separation combined with laser resonance Raman detection was developed for the determination of monosaccharides in fruit juices. Reducing sugars (galactose, glucose, mannose, arabinose, xylose and ribose) were derivatized with 4-dimethylaminoazobenzene-4'-sulfonyl (DABSYL) hydrazine. The derivatives of the monosaccharides exhibited strong resonance Raman scattering at 1136 cm(-1) when Ar+ laser emission line 488.0 nm was used. A semi-microcolumn Inertsil ODS-2 (250 mm x 1.5 mm i.d.) was used to the separation of the monosaccharide derivatives. The saccharides eluted within 25 min. However the excess DABSYL hydrazine was retained strongly with a retention time of about 60 min. In order to reduce the longer analysis time, the excess DABSYL hydrazine was removed by adding glyoxylic acid and then Na2CO3 aqueous solution when the derivation reaction was finished. As a result, the analysis time was reduced to about a half of its initial run time. The sensitivity of resonance Raman detection greater two orders of magnitude than refractive index (RI) detection. The detection limit of glucose is 10 ng (5.5 pmol). The high selectivity of Raman detection came from the facts that only the interested compounds in a given sample was derived with the Raman labeling reagent and that only the characteristic Raman bands of the derivatives were selectively detected. In this work, in spite of the coexisting large quantities of organic acids in fruit juice, the determined values of glucose agreed well with those obtained by RI detection without any derivatization procedure.

[Somatotopical mapping of the human somatosensory cortex with echo-planar MRI]

The somatotopical organization of the somatosensory cortex was analyzed. Echo-planar imaging was used to obtain functional images, and magnetic field strength was 1.5T. Natural stimulation at a frequency of 3 Hz (scrubbing or tapping) was applied to one of the three cutaneous areas: toes, fingertips, and tongue tip. The focal bands which show the significant signal increases were located on the contralateral post-central gyrus, and these changes of signal intensity originate from the cortical parenchyma because there were no major veins in the central sulcus. The focal bands which respond to each stimulation sites were anatomically distinct and located medially-to-laterally in the order of toes, fingertips, and tongue tip.

beta-Adrenergic stimulation induces activation of protein kinase C and inositol 1,4,5-trisphosphate increase in epidermis

Epidermal keratinocytes express beta 2-adrenergic receptors on the cell membrane. The binding of the agonists to the beta 2-adrenergic receptors regulates activation of adenylate cyclase. This transmembrane signaling system has been regarded to be one of the important pathways for the functions of keratinocytes. We previously reported that beta-adrenergic stimulation induced a transient increase of intracellular Ca2+ in normal human epidermal keratinocytes. Thus we investigated the effects of epinephrine on another transmembrane signaling system, the phosphatidyl-inositol signal transduction pathway in pig epidermis. Treatment of pig pure epidermis with epinephrine resulted in a transient increase in inositol 1,4,5-trisphosphate with a peak at 30 s. Epinephrine induced translocation of protein kinase C from cytosol to the membrane fraction. The activation of protein kinase C, translocation of protein kinase C from cytosol to the membrane fraction, was confirmed using the beta-adrenergic agonist isoproterenol. Moreover, the effect of epinephrine on the activation of protein kinase C was inhibited by preincubation with propranolol, a beta-adrenergic antagonist. The increase in inositol 1,4,5-trisphosphate and translocation of protein kinase C by epinephrine are consistent with the view that beta-adrenergic stimulation induces turnover of inositol phospholipid in pig epidermis.

Effects of mild hypothermia on nitric oxide synthesis following contusion trauma in the rat

The exact mechanism of hypothermic cerebroprotection after traumatic brain injury (TBI) is not fully understood. The present study was conducted to investigate the effects of mild hypothermia on trauma-induced synthesis of nitric oxide (NO), which has been implicated in the pathogenesis of ischemic brain damage associated with glutamate neurotoxicity. Cerebral contusion was created in the rat parietal cortex by a weight-drop method, and extracellular concentrations of the NO end products nitrite and nitrate were measured using in vivo brain microdialysis and capillary electrophoresis under normothermic (37 degrees C) and mild hypothermic (32 degrees C) conditions. In normothermic animals, the level of NO end products increased markedly 10 min after contusion, reaching a maximum level at 20 min. In the hypothermic rats, such increases were absent. Although it is unknown whether endothelial NO synthase, neuronal NO synthase, or both caused the elevation of the NO end products seen in the normothermic animals, the present results indicate that inhibition of NO synthesis may play a part in hypothermic cerebroprotection following TBI.

[Laboratory diagnosis of congenital thrombophilia]

We examined the incidence of thrombophilia in deep vein thrombosis (DVT). Of 38 cases, we found 4 cases of protein C abnormality, 2 cases each of protein S abnormality and lupus anticoagulant, 1 case of antithrombin III abnormality. The total incidence was 23.7%, whereas only 2 cases (6.2%) of plasminogen abnormality were found among 32 healthy individuals. The incidence of thrombophilia was apparently higher among patients with DVT than that of healthy subjects, although the incidence of Japanese DVT was lower than that of Caucasian DVT, as previously reported. By SSCP analysis in one case of protein C abnormality, we demonstrated an abnormality of exon 9-3. To establish laboratory diagnosis of thrombophilia, it is recommended that (1) severe liver diseases, DIC, and oral anticoagulant be ruled out, (2) abnormality be confirmed by repeated examination, (3) family study determine inheritance mode, if possible. It was strongly suggested that laboratory examination of thrombophilia should be routinely applied to cases of venous thrombosis including DVT, not only for diagnostic interest but also for appropriate treatment of these cases.

[A case of adenocarcinoma of the reconstructed bladder following ileocystoplasty]

We experienced a case of adenocarcinoma occurring in the reconstructed bladder 38 years after ileocystoplasty. The patient was a 48-year-old woman, who had undergone ileocystoplasty and left nephrectomy at the age of 10 for the treatment of tuberculous contracted bladder and left renal tuberculosis. She had often suffered from right pyelonephritis following the operation. She visited our hospital for work-up of a high value of carcinoembryonic antigen (CEA). The findings of cystoscopy, cystogram and urine cytology showed a malignant tumor of the reconstructed bladder. Then, we performed total cystectomy and right ureterostomy. The histopathological examination showed that the tumor was an adenocarcinoma which developed mainly from the ileal segment of the reconstructed bladder.