Verification of the minimal clinically important difference of the Capabilities of Upper Extremity Test in patients with subacute spinal cord injury

CONTEXT

The number of patients with cervical spinal cord injury (CSCI) is increasing, and the Capabilities of Upper Extremity Test (CUE-T) is recommended for introduction in clinical trials. We calculated the minimal clinically important difference (MCID) of the CUE-T using an adjustment model with an interval of 1 month.

DESIGN

This was a prospective study.

SETTING

This study was conducted with participants from the Chiba Rehabilitation Center in Japan.

PARTICIPANTS

The participants were patients with subacute CSCI.

INTERVENTIONS

The CUE-T and spinal cord independence measure (SCIM) III were performed twice within an interval of 1 month.

OUTCOME MEASURES

The MCID was calculated using an adjustment model based on logistic regression analysis. The participants were classified into an improvement group and a non-improvement group based on the amount of change in the two evaluations using the 10-point SCIM III MCID as an anchor.

RESULTS

There were 52 participants (56.8 ± 13.5 years old, 45 men/7 women) with complete or incomplete CSCI: 18 in the improvement group and 34 in the non-improvement group. A significant regression equation was obtained when calculating the MCID, and the total, hand, and side scores were 7.7, 2.0, and 3.7 points, respectively.

CONCLUSION

The calculated MCID of the CUE-T in this study was 7.7 points. The results of this study provide useful criteria for implementation in clinical trials. Future studies should use patient-reported outcomes, a more recommended anchor, and calculate the MCID using methods such as the patient's condition.

Anatomical Increased/Decreased Changes in the Brain Area Following Individuals with Chronic Traumatic Complete Thoracic Spinal Cord Injury

OBJECTIVES

This study aimed to investigate anatomical changes in the brain following chronic complete traumatic thoracic spinal cord injury (ThSCI) using voxel-based morphometry (VBM). That is, it attempted to examine dynamic physical change following thoracic injury and the presence or absence of regions with decreased and increased changes in whole brain volume associated with change in the manner of how activities of daily living are performed.

METHODS

Twelve individuals with chronic traumatic complete ThSCI (age; 21-63 years, American Spinal Injury Association Impairment Scale; grade C-D) participated in this study. VBM was used to investigate the regions with increased volume and decreased volume in the brain in comparison with healthy control individuals.

RESULTS

Decreases in volume were noted in areas associated with motor and somatosensory functions, including the right paracentral lobule (PCL)-the primary motor sensory area for lower limbs, left dorsal premotor cortex, and left superior parietal lobule (SPL). Furthermore, increased gray matter volume was noted in the primary sensorimotor area for fingers and arms, as well as in higher sensory areas.

CONCLUSIONS

Following SCI both regions with increased volume and regions with decreased volume were present in the brain in accordance with changes in physical function. Using longitudinal observation, anatomical changes in the brain may be used to determine the rehabilitation effect by comparing present cases with cases with cervical SCI or cases with incomplete palsy.

Pharmacological Properties of Propiverine Contribute to Improving Lower Urinary Tract Dysfunctions in Rats with Spinal Cord Injuries

Patients with spinal cord injury (SCI) usually develop lower urinary tract dysfunctions, including detrusor overactivity which is also known to be a risk factor for upper urinary tract dysfunction. Antimuscarinic agents, such as propiverine, have been used clinically for the treatment of detrusor overactivity. Also, propiverine has been known to possess antagonistic activity against L-type Ca²⁺ channels and transient receptor potential vanilloid subtype 1 (TRPV1), in addition to activity against muscarinic receptors. These mechanisms of action may contribute to improving detrusor overactivity in SCI. We therefore investigated the effects of antagonists of these mechanisms on non-voiding contraction (NVC) in SCI rats that are similar to clinical cases of detrusor overactivity, and considered whether these action mechanisms contribute to the incidence of NVC in SCI. Cystometry was performed in rats 4 weeks after spinal transection. Urinary functions were evaluated before and after intravenous administration of propiverine and specific antagonists for muscarinic receptors (atropine), L-type Ca²⁺ channels (verapamil), and TRPV1 (capsazepine). Propiverine markedly decreased the amplitude pressure of NVC in SCI rats, which was partially inhibited by atropine. Verapamil also suppressed the amplitude pressure of NVC to the same degree as propiverine. NVC disappeared almost completely after C-fiber desensitization, although capsazepine exerted no evident effects. These findings suggest that muscarinic receptors, L-type Ca²⁺ channels, and C-fiber afferent nerves contribute to the incidence of detrusor overactivity in SCI, and a drug that has multiple antagonistic effects, such as propiverine, is very effective for the treatment of lower urinary tract dysfunctions in SCI.

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging of the brain: Technique for suppression of enhancing venous signal

Purpose: Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging (BB-FSE) was performed to suppress enhancing venous signal and flow artifacts in the brain without sacrificing the T1-weighted imaging contrast.

Material and Methods: Twenty-five MR imaging sections (17 transverse and 8 coronal images) in 15 patients with various brain diseases were obtained by contrast-enhanced T1-weighted SE and BB-FSE images.

Results: In contrast-enhanced T1-weighted BB-FSE images, venous signal was significantly less and T1-weighted contrast of the brain was more evident. No differences in flow artifacts were found between the two imaging techniques. The interobserver agreements were good for the venous signal and flow artifacts using both techniques.

Conclusion: Contrast-enhanced T1-weighted BB-FSE imaging reduced the venous signal in the brain with maintaining T1-weighted contrast. This novel MR technique can be used when the suppression of enhancing venous signal is expected to improve the depiction of enhancing lesions in the brain.

Tipepidine activates VTA dopamine neuron via inhibiting dopamine D₂ receptor-mediated inward rectifying K⁺ current

We previously reported that the novel antidepressant-like effect of tipepidine may be produced at least partly through the activation of mesolimbic dopamine (DA) neurons via inhibiting G protein-coupled inwardly rectifying potassium (GIRK) channels. In this study, we investigated the action of tipepidine on DA D2 receptor-mediated GIRK currents (IDA(GIRK)) and membrane excitability in DA neurons using the voltage clamp and current clamp modes of the patch-clamp techniques, respectively. DA neurons were acutely dissociated from the ventral tegmental area (VTA) in rats and identified by the presence of the hyperpolarization-activated currents. Tipepidine reversibly inhibited IDA(GIRK) with IC50 7.0 μM and also abolished IDA(GIRK) irreversibly activated in the presence of intracellular GTPγS. Then tipepidine depolarized membrane potential and generated action potentials in the neurons current-clamped. Furthermore, the drug at 40 mg/kg, i.p. increased the number of cells immunopositive both for c-Fos and tyrosine hydroxylase (TH) in the VTA. These results suggest that tipepidine may activate DA neurons in VTA through the inhibition of GIRK channel-activated currents.

Changes in Ca(2+)/calmodulin-dependent protein kinase II activity and its relation to performance in passive avoidance response and long-term potentiation formation in mice prenatally exposed to diethylstilbestrol

We investigated the effects of prenatal exposure to diethylstilbestrol (DES), an endocrine disrupter on learning behavior and synaptic functions. Specifically, we determined the activity of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and related kinases that play an essential role in long-term potentiation (LTP) in the hippocampus in mice that were prenatally exposed to DES. Treatment with DES resulted in increased CaMKII autophosphorylation and Ca(2+)-independent activity in the hippocampus and cortex of male mice. Impaired passive avoidance correlated with this increased CaMKII autophosphorylation, as did the enhanced early phase of LTP (E-LTP) in hippocampus. These data suggest that prenatal exposure to DES induces deficits in passive avoidance responses as a result of increased CaMKII activity and hippocampal LTP.

Tri-n-butyltin-induced cytotoxicity on rat thymocytes in presence and absence of serum

Influence of fetal bovine serum (FBS) on cytotoxicity induced by tri-n-butyltin (TBT), an environmental pollutant, on rat thymocytes was examined to reveal how FBS modifies TBT cytotoxicity. As the medium FBS concentration was increased from 0 to 10%, the cytotoxicity of TBT was dose-dependently reduced when the cells were incubated with 1 microM TBT for 3 h. Almost complete inhibitions of TBT-induced changes in cell viability and population of cells with exposed phosphatidylserine (cells undergoing apoptosis) were observed when the FBS concentration was 10%. Thus, the cytotoxicity induced by 3 h incubation with TBT in FBS-free medium may be different from that in medium containing 10% FBS. However, even in presence of 10% FBS, TBT at concentrations ranging from 10 to 300 nM exerted cytotoxic action on rat thymocytes when the cells were incubated with TBT for 24 h. TBT dose-dependently increased the population of shrunken cells, of which more than 30% were stained with propidium. TBT at 30 nM or more significantly increased the population of cells with hypodiploid DNA, indicating TBT-induced apoptotic cell death. Thus, in the presence of 10% FBS, the prolonged incubation (24 h) of rat thymocytes with TBT at nanomolar concentrations induced apoptosis rather than necrosis.

Detection and characterization of focal liver lesions using superparamagnetic iron oxide-enhanced magnetic resonance imaging: comparison between ferumoxides-enhanced T1-weighted imaging and delayed-phase gadolinium-enhanced T1-weighted imaging

BACKGROUND

Double contrast magnetic resonance (MR) imaging using superparamagnetic iron oxide (SPIO) and gadolinium (Gd) is performed to detect and characterize focal liver lesions. However, this technique is a costly and lengthy process. The purpose of this study was to determine the usefulness of SPIO-enhanced MR imaging including SPIO-enhanced T1-weighted imaging in diagnosing focal liver lesions.

METHODS

Eighty-four focal liver lesions were examined with a 1.5-T MR unit. Transverse precontrast T1- and T2-weighted images and SPIO (ferumoxides)-enhanced T1- and T2-weighted images were obtained, followed by Gd-enhanced T1 -weighted imaging. The Gd set (i.e., precontrast T1- and T2-weighted and delayed-phase gadolinium-enhanced T1-weighted images) and ferumoxides set (i.e., precontrast T1- and ferumoxides-enhanced T1- and T2-weighted images) were reviewed by two independent readers.

RESULTS

More lesions were detected from the ferumoxides set than from the Gd set. Ferumoxides-enhanced T1-weighted imaging showed enhancement patterns of the lesions similar to those of delayed-phase Gd-enhanced T1-weighted imaging. The diagnoses of hepatic metastasis and cyst by the ferumoxides set were similar to those by the Gd set. However, a dynamic study may be inevitable for the diagnosis of hepatocellular carcinoma and hemangioma.

CONCLUSION

The ferumoxides set was useful for the detection of focal hepatic lesions. Ferumoxides-enhanced T1-weighted imaging may replace delayed-phase gadolinium-enhanced T1-weighted imaging in the diagnosis of hepatic metastasis and cysts.

Bradykinin activates airway parasympathetic ganglion neurons by inhibiting M-currents

The action of bradykinin on neurons acutely isolated from airway parasympathetic ganglia of rats and its mechanism were investigated using the nystatin-perforated patch-clamp recording technique. Under current clamp conditions, an application of 0.1 microM bradykinin onto rat airway ganglion neurons induced a depolarization which was accompanied by the action potential firing. Bradykinin elicited inward currents with decreasing the membrane conductance when a ganglion neuron was held at a holding potential of -40 mV. The half-maximum effective concentration was 8.9 nM. The bradykinin response was mimicked by a B(2) receptor agonist, [Hyp(3)]-bradykinin, and was inhibited by HOE-140, a B(2) antagonist, suggesting the contribution of B(2) receptors. The bradykinin-induced inward current reversed at the K(+) equilibrium potential, which shifted 56.5 mV with a 10-fold change in extracellular K(+) concentration. The application of 10(-3) M Ba(2+) induced the inward current, and bradykinin failed to evoke a further inward current in the presence of Ba(2+). Bradykinin also reduced the amplitude of M-current deactivation induced by a hyperpolarizing step from a holding potential of -25 mV to -50 mV with a half-maximum effective concentration of 16 nM. Pretreatment with pertussis toxin had no effect on the bradykinin-induced inhibition of the M-current. From these results we suggest that bradykinin may be able to depolarize the airway parasympathetic ganglion neurons of rats associated with an inhibition of M-type K(+) channels through the B(2) type of bradykinin receptors.

[Endocrine disruptors and brain estrogen receptors: the current state of behavioral, neurochemical, and molecular biological studies]

Based on epidemiological studies and animal studies, endocrine disrupters have received considerable attention as exerting disrupting actions on the developing brain. On the other hand, there has been increasing evidence that sex hormones and thyroid hormones play important roles in the development of the brain, including sexual dimorphism during the perinatal stage. Thus it seems probable that perinatal exposure to endocrine disruptors, which may have an affect on biosynthesis, transport, action, and metabolism of the hormones, may disrupt brain development enough to impair the brain functions. In this review, we introduce the current state of studies on brain disrupting actions of endocrine disruptors, addressing their actions on the estrogen system, including our own findings. The outline of the findings thus far reported are as follows: (1) Perinatal exposure to relatively low concentrations of endocrine disrupters may cause an impairment of higher brain functions, such as sexual behavior and learning behavior, (2) There seems to be sexual difference about the impairment described above, (3) Endocrine disruptors may cause an increase in volume of some nuclei, such as the sexual dimorphic nucleus of the preoptic area and locus coeruleus of the brain, (4) The disruptor might change the level of some substances that are considered to be involved in synaptic functions. Much remained to be studied about how does each finding reported link the others, and about detailed mechanisms of the disrupting actions of endocrine disruptors on the developing brain.

[Efficiency improvement of dispensing of drugs for injection by a total automatic injection dispenser system including infusion fluids and its evaluation]

For the appropriate use of drugs for injection, injection dispensing by pharmacists has been initiated at various institutions. With this movement, automatic injection dispensers have actively been developed. In our hospital, an injection order system was connected with an automatic injection dispenser in November, 1997, and this integrated system has been operating in all wards. However, the efficiency of dispensing work was not satisfactory because there were limitations in the types and volume of drugs placed in the automatic injection dispenser. Therefore, we constructed an automatic injection dispenser system that allows us to use more than 100 ml infusion fluids and also to use drugs stored in a cool place, which could not be used in the conventional system. In the new system, two trays coming from an ampoulevial line and an infusion fluid line are automatically coordinated using a discharge lifter for each patient and transported into an injection cart. After the introduction of this system, the automatic dispenser utilization rate in terms of the number of used injections increased from 52.6% to 73.3%. In addition, since the dispensing time for infusion fluids and drugs stored in a cool place, which had been collected by man power, was reduced, it became possible to pay more attention to checking for prescription.

Two members of the IgLON family are expressed in a restricted region of the developing chick brain and neural crest

The precise expression patterns of two IgLON genes, CEPU-1 and limbic system-associated membrane protein (LAMP), were studied during early embryogenesis. It was found that expression of both was localized to restricted regions of the brain and neural crest. In the developing neural tube, CEPU-1 was expressed in the isthmus and a restricted region of the hindbrain, whereas LAMP was expressed in the anterior midbrain. Most neural crest cells expressed LAMP, whereas CEPU-1 expression was limited to crest cells derived from the hindbrain. These results suggest that members of the IgLON family have important roles during embryogenesis, particularly in brain formation and differentiation.

[Intestinal permeability in Crohn's disease and effects of elemental dietary therapy]

Enteral intake of non-metabolic monosacharide and disaccharide, followed by measurement of the urinary excretion ratio of the two, is a method used to investigate intestinal permeability. L/R ratio (lactulose/1-rhamnose urinary excretion ratio) is considered an indicator of permeability of the small intestine. An increased L/R ratio is caused by mucosal disorders of the small intestine. The L/R ratio in all patients (n = 92) with Crohn's disease was 0.079 +/- 0.081 (mean +/- S.D.), which was significantly higher than the value in normal controls (0.027 +/- 0.009, n = 20, p < 0.05). In 39 patients with Crohn's disease, we assessed intestinal permeability before after treatment with an elemental diet, and during remission. The L/R ratio was 0.120 +/- 0.092, before treatment and 0.065 +/- 0.097 after treatment (p < 0.05), showing increased intestinal permeability before elemental dietary treatment. During remission, the L/R ratio was 0.035 +/- 0.028; this did not differ significantly from the value obtained after treatment. We conclude that intestinal permeability is useful for investigating disease activity in patients with Crohn's disease.

Interaction between beta-adrenergic signaling and protein kinase C increases cytoplasmic Ca2+ in alveolar type II cells

The interaction between beta-adrenergic signaling and the activation of protein kinase C in alveolar type II cell plays an important role in the regulation of surfactant secretion because the combined application of beta-adrenergic agonist with protein kinase C activator to the cells stimulates the secretion synergistically. However, the mechanisms underlying the interaction are not clear. In the present study, we examined the combined effect of terbutaline with phorbol 12-myristate 13-acetate (PMA) on cytoplasmic free Ca2+ concentration ([Ca2+]i) in rat alveolar type II cells. The combined application of terbutaline with PMA to the cells rapidly increased [Ca2+]i, although neither of them affected it by itself. Similar increases of [Ca2+]i were observed in other combinations, such as terbutaline with 1-oleoyl-2-acetyl-sn-glycerol, and forskolin with PMA. Either the removal of extracellular Ca2+ or the addition of Co2+ remarkably suppressed the increase of [Ca2+]i induced by the combination of terbutaline with PMA. In addition, Co2+ inhibited the phosphatidylcholine secretion induced by the combination of terbutaline and PMA. These results suggested that the [Ca2+]i increased as a result of the interaction between formation of cyclic AMP and activation of protein kinase C in alveolar type II cells, and that the increase in [Ca2+]i was mediated by the Ca2+ influx through the plasma membrane. This mechanism to modulate [Ca2+]i may play a role in the regulation of surfactant secretion by alveolar type II cells.

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging of the brain. Technique for suppression of enhancing venous signal

PURPOSE

Contrast-enhanced T1-weighted black-blood fast spin-echo MR imaging (BB-FSE) was performed to suppress enhancing venous signal and flow artifacts in the brain without sacrificing the T1-weighted imaging contrast.

MATERIAL AND METHODS

Twenty-five MR imaging sections (17 transverse and 8 coronal images) in 15 patients with various brain diseases were obtained by contrast-enhanced T1-weighted SE and BB-FSE images.

RESULTS

In contrast-enhanced T1-weighted BB-FSE images, venous signal was significantly less and T1-weighted contrast of the brain was more evident. No differences in flow artifacts were found between the two imaging techniques. The interobserver agreements were good for the venous signal and flow artifacts using both techniques.

CONCLUSION

Contrast-enhanced T1-weighted BB-FSE imaging reduced the venous signal in the brain with maintaining T1-weighted contrast. This novel MR technique can be used when the suppression of enhancing venous signal is expected to improve the depiction of enhancing lesions in the brain.

Investigation of the association between infection with Helicobacter pylori and with TT virus, a novel DNA virus, in patients with gastroduodenal ulcer or ulcer scar

OBJECTIVE

Recently, a novel DNA virus (TT virus; TTV) has been isolated. Enteric transmission is suggested as a route of transmission of TTV, with high prevalence of this virus infection in the general population, and age and geographical distributions of TTV prevalence very similar to those of Helicobacterpylori infection. We analysed an association between TTV and H. pylori infection in patients with gastroduodenal ulcer or ulcer scar.

METHODS

In 181 patients with a gastroduodenal ulcer or ulcer scar (102 with a gastric lesion, 60 with a duodenal lesion, and 19 with both sites involved), specimens were cultured for H. pylori and TTV infection was sought in serum by a polymerase chain reaction.

RESULTS

H. pylori infection was demonstrated in 152 patients (84.0%) and TTV was detected in 168 patients (92.8%). Patients with TTV were significantly older than those without TTV (P = 0.0001), while no age difference was observed between patients with and without H. pylori infection. No difference was apparent in the prevalence of TTV infection between patients with and without H. pylori infection, and vice versa.

CONCLUSIONS

We found no association between TTV infection and H. pylori infection in patients with peptic ulcer diseases, which is consistent with a lack of association between TTV infection and peptic ulcer. However, larger studies including surveys of the general population will be required to analyse the overall association between TTV and H. pylori.

Toxicity of methylmercury conjugated with L-cysteine on rat thymocytes and human leukemia K562 cells in comparison with that of methylmercury chloride

In order to reveal the implication of use of methylmercury chloride (MeHgCl) in in vitro study, the effects of 10 µM MeHgCl on rat thymocytes and human leukemia K562 cells were compared with those of methylmercury conjugated with L-cysteine (10 µM MeHg-Cys) using a flow cytometer and fluorescent probes to monitor cellular physiological and pathological parameters. MeHgCl hyperpolarized membranes of thymocytes, followed by depolarization within a few minutes after the application, while MeHg-Cys persistently hyperpolarized them. MeHgCl increased intracellular concentration of Ca(2+), decreased cellular content of glutathione and increased generation of superoxide anion in the cells. The effects of MeHg-Cys were much less than those of MeHgCl. MeHgCl greatly increased both numbers of the cells undergoing apoptosis and dead cells in cell suspension containing thymocytes, while this was not the case for MeHg-Cys. MeHgCl reduced the cell viability of human leukemia K562 cells and completely inhibited the cell growth. The effects of MeHg-Cys on K562 cells were less than those of MeHgCl. It can be concluded that the effects of MeHgCl on rat thymocytes and K562 cells are different from those of MeHg-Cys. The results obtained from the in vitro studies using MeHgCl may be less implicit to elucidate the mechanism of MeHg intoxication in humans and experimental animals because MeHg are present in forms of MeHg-Cys and/or MeHg-S conjugate under the in vivo conditions.

[Survey on postmortem examination to police surgeons and emergency physicians. Possibility of physicians' assist in mass-disaster]

We conducted a questionnaire survey of police surgeons and emergency physicians, inquiring about their experience of medicolegal investigation of death and their willingness to join a death investigation team in a major disaster. The questionnaire also asked about their knowledge about and interest in the forensic specialist system established by the Japanese Society of Legal Medicine. Police surgeons were generally willing to join an investigation team only if a disaster occurred in or close to their hometown, because they could not afford more than several days away from patient care. Although many of the emergency physicians were willing to join a death investigation team, they had difficulty in doing so without permission or orders from their employer or the authorities concerned. The survey found that the percentage of aged police surgeons was increasing among those surveyed. This fact, in combination with the current emphasis of postgraduate education on specialty training, threatens to cause a substantial lack of physicians available for medicolegal investigation of death. Therefore, it is urgently necessary to establish a system of training resident and emergency physicians in medicolegal investigation of death. In addition to providing postgraduate training in medicolegal investigation of death to prospective trainees who are emergency physicians at major hospitals in potential disaster-stricken areas, the medical school should incorporate forensic medicine in postgraduate training programs so that they can actively perform death investigation on disaster victims dying before or after arrival at their hospitals. Furthermore, the forensic community should make every effort to increase the number of autopsies in each department of forensic medicine and to expand the medical examiner system throughout Japan that is currently in practice only in the Metropolis of Tokyo and Yokohama, Nagoya, Osaka and Kobe Cities in order to incorporate forensic training in the postgraduate clinical training programs that will become compulsory in 2004.

Determination of pancreas injury from bloodstains using human pancreatic elastase III as a marker

A sensitive sandwich enzyme immunoassay for human pancreatic elastase III as a method to identify pancreas injuries from blood or bloodstains was evaluated. The serum levels of human elastase III from healthy adults (n=24) were estimated to be 1.15 +/- 0.6 (+/- SD) ng/ml. The recovery rates of elastase III added to normal human serum were estimated to be 96.3%. Elastase III levels in contents of various digestive organs were assayed and found to be high in the contents of the large intestine. For detection of human elastase III on weapons, samples were prepared from disposable scalpels that had been used to cut skin and skeletal muscle, and then to cut various organs. The mean ratio of elastase III to total protein (ng elastase III/mg protein) on scalpels that had been cut the pancreas (n=11) was 4956+/-3067 (+/- SD), whereas the ratios from other organs were much lower except, in case of several digestive organs. The higher elastase III levels detected in these digestive organs seemed to stem from the amount of intestinal contents adhering to the scalpels. These results suggest that determination of pancreatic elastase III in blood or bloodstains using a sandwich enzyme immunoassay is a very useful and effective tool for identification of pancreas injury in forensic practice.

Non-competitive inhibition of kainate-induced currents by diethylstilbestrol in acutely isolated mouse CA1 hippocampal neurons

The effect of a synthetic estrogen, diethylstilbestrol (DES), on kainate-induced currents was investigated in the hippocampal CA1 pyramidal neurons acutely dissociated from the mice using the nystatin-perforated patch-clamp recording configuration under voltage-clamp conditions. DES inhibited the current evoked by 100 microM kainate in a concentration-dependent manner with a half-maximum inhibitory concentration of 8.8 microM. The action of DES was voltage-independent. Since DES produced a suppression of the maximum response of the kainate concentration-response curve, the inhibition by DES of the kainate-induced current appears to be non-competitive.

A sandwich enzyme immunoassay for human pancreatic elastase III

To develop a method for the determination of pancreas injuries using a pancreas-specific antigen as a marker, human elastase III was purified from the pancreas by chromatographic methods. A rabbit anti-human elastase III antibody was prepared, and this antibody was confirmed using immunoblotting to react only with elastase III among proteins from the pancreas. A sensitive sandwich enzyme immunoassay for human elastase III was developed. The detection limit for human elastase III was 0.3 pg (10 amol) per assay. Proteins extracted from the pancreas showed the strongest response, whereas reactions of the other organs were less than the detection limit. These results suggest that a sandwich enzyme immunoassay for human elastase III is useful for the determination of pancreas injury.

Inhibition of the 5-HT(1A) receptor-mediated inwardly rectifying K(+) current by dextromethorphan in rat dorsal raphe neurones

The effect of dextromethorphan (DM) on the inwardly rectifying K(+) currents mediated by 5-HT(1A) receptors in acutely dissociated dorsal raphe (DR) neurones of rats was studied using nystatin-perforated patch and conventional whole-cell patch recording configurations under voltage-clamp conditions. DM rapidly and reversibly inhibited the K(+) currents induced by 10(-7) M 5-HT in a concentration-dependent manner with a half-maximum inhibitory concentration of 1.43 x 10(-5) M. The inhibitory effect of DM was neither voltage- nor use-dependent. DM caused a suppression of the maximum response of the 5-HT concentration-response curve, thus suggesting a non-competitive type of inhibition. In neurones perfused intracellularly with a pipette-solution containing the nonhydrolyzable GTP analog GTPgammaS, 5-HT activated K(+) currents in an irreversible manner. DM suppressed the current irreversibly activated by intracellular GTPgammaS even in the absence of the agonist. DM also inhibited the inwardly rectifying K(+) currents regulated by alpha(2)-adrenoceptors in freshly isolated rat locus coeruleus neurones. These results suggest that DM may inhibit the G-protein coupled inwardly rectifying K(+) channels, but not the neurotransmitter receptors, in the central nervous system.

Changes in mRNA expression levels of synaptic- and target tissue-specific proteins after organophosphate exposure

We examined the effects of organophosphate exposure on mRNA expression levels of synaptic- and target tissue-specific proteins in rats. We treated rats with a single dose of Disulfoton (O,O-diethyl S-2-ethylthioethyl phosphorodithioate) and used quantitative reverse transcription-polymerase chain reaction (RT-PCR) to measure the time course of changes in the levels of mRNAs encoding acetylcholinesterase (AChE), nicotinic acetylcholine receptor (nAChR), beta-enolase (MSE), and gamma-enolase (NSE) in soleus muscles and sciatic nerves. The expression levels of synaptic genes encoding AChE in both tissues were significantly decreased, with a nadir at 12h after the administration, and this down-regulation lasted for up to 30 days after administration. Similarly, the level of nAChR mRNA in soleus muscle also decreased, with a nadir at 48 h after administration and a return to 95% of that of the control levels by 30 days after administration. These results indicate that administration of organophosphate can decrease AChE and nAChR expression in the neuromuscular junction, and are suggestive of multiple mechanisms of down-regulation of both AChE and nAChR, some of which might involve alterations at the transcriptional level. The transcript level of the target tissue-specific gene encoding MSE in soleus muscle was slightly decreased, with a nadir at 48 h after administration, and was still lower than that of the control level after 30 days. In contrast, the level of the NSE transcript in sciatic nerve significantly increased within 2 h, and this up-regulation was sustained until 30 days after administration. Although the functions of either of these enolases are not completely established, up-regulation of NSE mRNA may be a marker for the nervous system abnormality following organophosphate exposure. All of these phenomena may contribute to the long-lasting neurotoxic effects observed after developmental exposure to organophosphates.

Identification of remains by sequencing of mitochondrial DNA control region

The maternity of two newborns who were murdered and abandoned >5 and 10 years were analyzed by amplification and direct sequencing of mitochondrial DNA (mtDNA) control regions. Sequences of two hypervariable segments from each femur bone sample and the blood of the putative mother showed four mutations in hypervariable region I and two mutations in addition to two nucleotide insertions in hypervariable region II compared with the reference sequence, and all sequences were identical. The genotype of these individuals is found to be relatively rare in the Japanese population, and it was strongly suggested that both sets of newborn remains really were children of the putative mother. Sexes of the remains were determined to be female and male by amplifying a segment of the X-Y homologous gene, amelogenin. These results demonstrate that sequencing of mtDNA is a useful tool for genetic identification of aged and decomposed materials.

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.

A novel method of species identification using human muscle-specific beta-enolase

A novel method of species identification using a sensitive sandwich enzyme immunoassay for human muscle-specific beta-enolase was used to analyze bloodstains and skeletal muscle. Human beta-enolase is detectable in human blood at dilutions up to 3 x 10(3) and human muscle extract (0.1 g/ml) at dilutions up to 5 x 10(6) using a sandwich enzyme immunoassay. The cross-reactivities of both blood and skeletal muscle extracts from other species were 0.01 or less. When human skeletal muscle extract was added in a final concentration of 10 mg/ml, the ratio of beta-enolase to total protein in bloodstains was approximately 1000, whereas the addition of skeletal muscle extract of other species resulted in a ratio of less than 10. Application of this method in a practical case proved that human muscle-specific beta-enolase as a marker for species identification is very effective in forensic practice.

Preferential inhibition of L- and N-type calcium channels in the rat hippocampal neurons by cilnidipine

The effect of a dihydropyridine Ca2+ antagonist, cilnidipine, on voltage-dependent Ca2+ channels was studied in acutely dissociated rat CA1 pyramidal neurons using the nystatin-perforated patch recording configuration under voltage-clamp conditions. Cilnidipine had no effect on low-voltage-activated (LVA) Ca2+ channels at the low concentrations under 10(-6) M. On the other hand, cilnidipine inhibited the high-voltage-activated (HVA) Ca2+ current (I(Ca)) in a concentration-dependent manner and the inhibition curve showed a step-wise pattern; cilnidipine selectively reduced only L-type HVA I(Ca) at the low concentrations under 10(-7) and 10(-6) M cilnidipine blocked not only L- but also N-type HVA I(Ca). At the high concentration over 10(-6) M cilnidipine non-selectively blocked the T-type LVA and P/Q- and R-type HVA Ca2+ channels. This is the first report that cilnidipine at lower concentration of 10(-6) M blocks both L-and N-type HVA I(Ca) in the hippocampal neurons.

[Unusual form of ulcerative colitis]

Segmental colitis which showed the similar findings of ulcerative colitis and right-sided colitis with back-wash ileitis has been considered as the unusual form of ulcerative colitis. Today, we have few opportunities to come across those cases, because modern diagnosis of colon disease could make differential diagnosis easily with the sense of broad spectrum of IBD. We presented three cases of segmental colitis and one case of so-called indeterminate colitis associated of carcinoma in the cecum and discussed the clinical significance for diagnosis and finding the step of studying the etiology of IBD. Especially, in the third case, thirteen years old man was showing the sign of early stage of Crohn disease with non-caseating granuloma in the biopsy specimen at first, the findings of the segmental ulcerative colitis with crypt abscess were seen after six months in the second examination. To observe the detail changes of the mucosal lesion in this kind of cases will present the new idea for studying the etiology of IBD.

Y chromosome DNA polymorphisms and their haplotypes in a Japanese population

Allele frequencies of two Y chromosome-specific short tandem repeats, locus DYS385 and DYS19, in addition to the Y Alu polymorphic (YAP) insert (DYS287) were investigated in blood samples obtained from 270 unrelated Japanese in Miyazaki Prefecture (south Japan). A total of 47 genotypes in DYS385 and 6 in DYS19 were detected, and the frequency of the YAP(+) allele was found to be 35.2% (95270). The allele distributions of each locus revealed significant differences compared with those in other populations. One hundred and twelve different haplotypes were observed in the combined 55 alleles of three loci. The gene diversity values range 0.96 for DYS385 and 0.71 for DYS19, and the combination haplotype diversity value is 0.98.

Mucolytic and antitussive effects of erdosteine

To investigate the influence of erdosteine, a new homocysteine-derived expectorant, on airway clearance we studied the effects of the drug on the viscosity of mucin, on the mucociliary transport rate in quails, on airway secretion in rats and on the cough reflex in guinea-pigs. The active metabolite of erdosteine, M1 (10 microM to 1 mM), significantly reduced the viscosity of porcine stomach mucin. Erdosteine by itself did not reduce viscosity. Erdosteine significantly promoted mucociliary transport in quails and increased airway secretion in rats. The effect was still apparent 24h after administration. Erdosteine significantly suppressed citric acid-induced cough reflexes in guinea-pigs but did not suppress mechanical stimuli-induced cough reflexes. Erdosteine suppressed the reduction of the recovery volume of bronchoalveolar lavage fluid and albumin leakage into the fluid in citric acid-exposed guinea-pigs. These results indicate that erdosteine removes sputum by reducing its viscosity, and by promoting mucociliary transport and sustained enhancement of airway secretion. It also suppressed the chemical stimulation-induced cough reflex and plasma leakage into the airway. These results suggest that erdosteine is an excellent expectorant with several modes of action.

[Composition of vascular tree using moving-table MR angiography: development and preliminary clinical experience with a semi-automated program combining stacks of MR angiographic images]

Moving-table MR angiography, combining a contrast enhanced MRA approach with table movement, has recently become available. This technique allows imaging of long, longitudinal anatomical regions of vasculature. We have developed a semi-automated program combining stacks of MRA images obtained from different image stations, and applied it to the reconstruction of vascular trees in twenty-five patients with peripheral arterial occlusive disease. Using this program, continuous vascular trees, extending from the abdominal aorta to lower leg (up to 124 cm), were semi-automatically reconstructed within two minutes from six different projection angles. Extensive vascular lesions were recognized three-dimensionally by moving image display mode.

Left ventricular function at rest and during bicycle exercise in normal subjects: assessment by ECG-gated myocardial perfusion SPET with 99Tcm-tetrofosmin

99Tcm-labelled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function using ECG-gated SPET. The aim of this study was to evaluate left ventricular performance during exercise by means of ECG-gated myocardial perfusion SPET. After the administration of 99Tcm-tetrofosmin (555-740 MBq), eight healthy volunteers aged 27-49 years underwent ECG-gated myocardial perfusion SPET at rest and during supine submaximal exercise (75 and 125 W), for 3 min each. Using ECG-gated SPET data, left ventricular end-diastolic volume (LVEDV) demonstrated a biphasic response during exercise (from 106.4 +/- 17.5 to 119.9 +/- 19.9 to 108.1 +/- 19.2 ml). In contrast, left ventricular end-systolic volume decreased gradually and significantly during exercise (from 47.1 +/- 11.9 to 41.5 +/- 8.9 to 36.1 +/- 10.1 ml; P < 0.05), and left ventricular ejection fraction continued to increase at higher workloads (from 56.1 +/- 6.0 to 63.0 +/- 2.7 to 67.0 +/- 4.3; P < 0.01) despite a fall in LVEDV. There was a progressive increase in cardiac output during exercise, which reached a peak of 7.2 +/- 0.9 l.min-1. We conclude that ECG-gated myocardial perfusion SPET can assess left ventricular function during exercise and may provide useful information for the evaluation of patients with ischaemic heart disease.

A sandwich enzyme immunoassay for human muscle-specific beta-enolase and its application for the determination of skeletal muscle injury

A sensitive sandwich enzyme immunoassay for human beta-enolase was developed and used to examine beta-enolase in blood or bloodstains as a marker for the determination of skeletal muscle injury. Human beta-enolase was purified from human skeletal muscle, and then an antibody against it was prepared. Polystyrene balls coated with rabbit anti-human beta-enolase IgG were incubated with human beta-enolase and then with anti-human beta-enolase Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene balls was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as a hydrogen donor. The detection limit for human beta-enolase was 2.6 pg (30 amol) per assay. The degree of cross-reaction of the sandwich enzyme immunoassay for other organs except for heart (1/10) was about 1/150 or less. Moreover, the localization of beta-enolase in various human tissues was examined by Northern blot analysis, and this confirmed that beta-enolase was expressed only in skeletal and cardiac muscle. Antigenic activity in bloodstains containing beta-enolase was recovered well after storage for 60 days at room temperature. The ratio of beta-enolase to total protein in bloodstains made from non-traumatic blood, nasal hemorrhage and menstrual blood, was within the normal range. In contrast, the ratio of beta-enolase in bloodstains from traumatic blood was obviously elevated (10-30 fold) in comparison with non-traumatic blood. Furthermore, the ratio of beta-enolase was proved to be higher in stains adhering to weapons that had passed through skeletal muscle, indicating that detection of beta-enolase in bloodstains could be used to distinguish crime weapons. These results suggest that beta-enolase is a useful marker for identification of skeletal muscle injury as well as for detecting the origin of bleeding.

Sequence polymorphism of mitochondrial DNA control region in Japanese

Sequence polymorphisms of the mitochondrial DNA (mtDNA) control region, hypervariable regions I and II, from 100 unrelated Japanese were determined by PCR amplification and direct sequencing. Sequences of 404 nucleotides for hypervariable region I and 379 nucleotides for region II were obtained. Variable sites (85 and 45) were revealed in region I and region II, respectively, as compared to the reference sequence, and a total of 96 different genetic patterns from both regions I and II were determined. A point mutation heteroplasmy was observed at the ratio of approximately 50:50 from one individual at the sequence position 151 showing a nucleotide transition from C to T. The probability of identity was estimated as 2.3% for region I, 3.9% for region II, and 1.1% combined for both regions. These results suggest that sequence polymorphism of mtDNA control region would be very useful in forensic practice as a marker for individual identification.

Development of a new method for simultaneously evaluating mucociliary clearance and pulmonary epithelial permeability in rabbit experiments by means of 18FDG, three-dimensional positron emission tomography and rectilinear scan

We tried to simultaneously obtain the elimination constant of mucociliary clearance and the pulmonary epithelial permeability constant after inhalation of 2-[18F]fluoro-2-deoxy-D-glucose (18FDG) solution by carrying out whole lung positron emission tomography and a rectilinear scan in rabbit experiments. The elimination constant of pulmonary epithelial permeability was obtained from the decrease in the amount of the radioactivity with time in the region of interest (ROI) confined to the lungs, trachea and tracheal cannula in the rectilinear scan. The total elimination constant of the radioactivity in the lungs was obtained from the ROI confined to the lungs in the tomography. The mucociliary clearance rate constant in the lungs was then obtained after subtracting the elimination constant of the pulmonary epithelial permeability from the total elimination constant of the 18FDG in the lungs. The mucociliary clearance constant in the trachea was calculated from the residual radioactivity in the trachea and the mucociliary clearance constant in the lungs. The mean pulmonary epithelial permeability constant was 0.0020% min(-1) obtained from the rectilinear scan. The mean mucociliary clearance constants of the lungs and the trachea were 0.0006 and 0.025% min(-1), respectively. These results indicated that the pulmonary epithelial permeability and mucociliary clearance could be evaluated simultaneously with 18FDG by using three-dimensional positron emission tomography and a rectilinear scan.

A family with Liddle's syndrome caused by a new missense mutation in the beta subunit of the epithelial sodium channel

Liddle's syndrome is an autosomal dominant form of salt sensitive hypertension caused by mutations in the beta or gamma subunit of the epithelial sodium channel. Systematic mutagenesis studies revealed that a conserved PPPXY sequence (PY motif) of the C-terminus of the alpha, beta, or gamma subunits might be involved in the regulation of the channel activity. However, only two missense mutations in the PY motif of the beta subunit have been reported to cause Liddle's syndrome. We sequenced the C-termini of the beta and gamma subunits of the epithelial sodium channel in a Japanese family clinically diagnosed as having Liddle's syndrome and found a new missense mutation in the PY motif of the beta subunit, P615S. Expression studies with P615S mutant in Xenopus oocytes resulted in an about 3-fold increase in the amiloride-sensitive sodium current compared to the wild type (p = 0.001). These findings provide further clinical evidence for the hypothesis that a conserved PY motif may be critically important for the regulation of the epithelial sodium channel.

Effects of SS320A, a new cysteine derivative, on the change in the number of goblet cells induced by isoproterenol in rat tracheal epithelium

We examined the effects of SS320A ((-)-(R)-2-amino-3-(3-hydroxypropylthio)propionic acid), a new cysteine derivative, on the change in the number of goblet cells induced by isoproterenol in rat tracheal epithelium. Four types of goblet cells were characterized in tracheal epithelium according to their size and staining affinity with Alcian blue (AB) / periodic acid Schiff (PAS). When each rat was given a single daily injection of isoproterenol (0.05 mg/kg, i.p.) for 14 days, a significant increase was observed in AB/PAS-positive cells that were recognizable as goblet cells in tracheal epithelium. When SS320A (10-100 mg/kg, p.o.) or propranolol (1 mg/kg, s.c.) was administered before each injection of isoproterenol, the increase in the number of goblet cells induced by isoproterenol was significantly inhibited. There was no difference between male and female rats with regard to this inhibitory action. On the other hand, ambroxol, bromhexine, L-cysteine ethyl ester and S-carboxymethylcysteine (100 mg/kg, p.o., respectively), which are used as expectorants, had no inhibitory effects on the isoproterenol-induced change in the number of goblet cells. Four metabolites (M1-M4) of SS320A in rats also failed to inhibit the change induced by isoproterenol. These data suggest that SS320A itself may have a beneficial effect against mucus hypersecretion in chronic respiratory diseases.

Inhibition of glycine-induced current by morphine in nucleus tractus solitarii neurones of guinea pigs

We studied the effect of morphine on the current induced by glycine in acutely dissociated nucleus tractus solitarii (NTS) neurones of guinea pigs, by use of the whole-cell patch clamp technique. Morphine inhibited 30 microM glycine-induced current (Igly), without affecting the current caused by 30 microM GABA. The effect of morphine was concentration-dependent, with a maximal effect at 1 mM, and reversible. The half-maximum inhibitory concentration of morphine was 30 microM. The effect of morphine was not depressed by naloxone, an opioid antagonist. Furthermore, the effect was not substantially affected by methiothepin, a 5-HT1 antagonist, ketanserin, a 5-HT2 antagonist and MDL-72222, a 5-HT3 antagonist. Morphine at 30 microM shifted the concentration-response curve for Igly to the right without affecting the maximum value. The effect of morphine on Igly showed no use-dependence. The results indicate that morphine inhibits Igly in the NTS neurones, and further suggest that morphine at the concentration used may act on the glycine receptor-ionophore complex, but not on the Cl-channel of the complex.

Current opinion of muco-active drug research: strategies and problems

In general, mucoactive drugs are classified into several groups. However, since many drugs have overlapping effects, it is difficult to classify the drugs into groups based on their major actions. It has been reported that many mucoactive drugs have antioxidant effects. It is reasonable to suggest that an anti-inflammatory property is crucial to demonstrate effectiveness in a clinical context. From this point of view, we have evaluated several mucoactive drugs over two decades. Of these, we will consider the following drugs with anti-inflammatory properties: sodium aceneuramate; glucocorticoids; traditional Chinese medicines; and new cysteine derivatives. On the basis of these findings, we believe that the efforts to seek for compatible actions between glucocorticoids and oriental medicines may provide new opportunities for development of ideal mucoactive drugs with specified actions, i.e. suppression of gene expression.

Effects of xanthine derivatives on phosphatidylcholine secretion in rat type II pneumocytes in the presence of activated eosinophils

We have previously reported that activated eosinophils enhanced the phosphatidylcholine (PC) secretion in type II pneumocytes. In this study, we have determined whether xanthine derivatives affect the PC secretion increased by activated eosinophils. Theophylline enhanced the increased PC secretion at 10(-5) M. 8-Phenyltheophylline dose-dependently enhanced the PC secretion. The enhanced secretion by either theophylline at 10(-5) M or 8-phenyltheophylline was suppressed by superoxide dismutase in combination with catalase. Pentoxifylline did not enhance the PC secretion increased by activated eosinophils, although it increased the PC secretion by itself. The PC secretion increased by theophylline at 10(-3) M or pentoxifylline was not suppressed by superoxide dismutase in combination with catalase. The present results suggest that xanthine derivatives increased the PC secretion in the co-culture of type II pneumocytes and activated eosinophils possibly through the inhibition of phosphodiesterases or the antagonism of adenosine receptors of the eosinophils.

Effect of human neutrophil elastase on tracheal mucociliary transport in anesthetized quails

We investigated the effect of human neutrophil elastase (HNE) on tracheal mucociliary transport in anesthetized quails. Topical application of HNE (30-300 microg/kg) to tracheal mucosa dose-dependently decreased mucociliary transport velocity (MCTV). The HNE (300 microg/kg)-induced decrease in MCTV was blocked by ONO-5046 x Na (sodium N-[2-[4-(2,2-dimethylpropionyloxy)phenyl-sulfonylamino]benzo yl]aminoacetate tetrahydrate) (3-30 mg/kg, i.m.), a specific neutrophil elastase inhibitor. Furthermore, we found that HNE increased DNA, fucose and protein contents of tracheal lavages, and the increases were also reverted by ONO-5046 Na. These results indicated that HNE decreased tracheal mucociliary transport, and the decrease may be, at least in part, ascribed to the deterioration of tracheal secretions.

Bispecific rabbit Fab'-bovine serum albumin conjugate used in hemagglutination immunoassay for beta-microseminoprotein

A polyclonal bispecific (bifunctional) antibody was prepared to develop a hemagglutination immunoassay for beta-microseminoprotein (beta-MSP), a predominant seminal protein. Three types of F(ab')2 fragments of rabbit IgG, affinity-purified anti-human red blood cell (RBC) F(ab')2 nonaffinity-purified anti-beta-MSP F(ab')2 and nonspecific (nonimmunized) F(ab')2, were mixed to obtain a F(ab')2 mixture containing 10% anti-RBC molecules and 10% anti-beta-MSP molecules. Fab' was obtained from the F(ab')2 mixture, and then reacted with maleimide-activated bovine serum albumin (BSA) at a molar ratio of 10:1. As estimated by the decrease in the maleimide content, approximately 7 Fab' molecules were introduced per one BSA molecule. The bispecific (anti-beta-MSP and anti-RBC) Fab'-BSA conjugate thus prepared was incubated successively with a human RBC suspension and with samples. In the presence of beta-MSP, RBCs become agglutinated, providing a test simple for forensic semen identification.

Differential effect of codeine on coughs caused by mechanical stimulation of two different sites in the airway of guinea pigs

We studied the difference in the effects of codeine on coughs caused by mechanical stimulation to the larynx and to the bifurcation of the trachea in lightly anaesthetized guinea pigs. Mechanical stimulation to the larynx or the bifurcation of trachea caused a stable cough response. The response was reproducible over 60 min, when stimulation was repeatedly applied at 20-min intervals. No significant difference was found between the amplitudes of the responses to mechanical stimulation of the larynx and of the tracheal bifurcation. Codeine, 10, 20 and 50 mg/kg, dose dependently depressed the coughs caused by larynx stimulation. The antitussive, however, failed to depress the cough caused by stimulation to the tracheal bifurcation, although a large dose, 50 mg/kg, significantly depressed the cough. In capsaicin-treated guinea pigs, codeine at 20 mg/kg significantly depressed the cough caused by stimulation to the tracheal bifurcation. The present results suggest that cough caused by mechanical stimulation to the larynx might be more sensitive to codeine treatment than cough caused by stimulation to the bifurcation of trachea. Furthermore, it is suggested that coughs caused by mechanical stimulation to both sites might consist of at least two components as regards their pharmacological nature.

A sandwich enzyme immunoassay for brain S-100 protein and its forensic application

A sensitive sandwich enzyme immunoassay for identification of brain S-100 protein in blood or bloodstains containing brain tissue is described. A polystyrene ball coated with rabbit anti-S-100 protein IgG was incubated with human S-100 protein, and then with anti-S-100 Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human S-100 protein was 0.6 pg (30 amol) per assay tube. The cross-reaction of this sandwich enzyme immunoassay to other organs was approximately 1/100 or less. Antigenic activity of S-100 protein in bloodstains containing brain extracts was detectable after storage for 36 days at room temperature. The ratio of S-100 protein to total protein (ng/mg) in bloodstains when brain tissue was mixed with normal human blood at concentrations of 5-500 mg/ml was approximately 100-fold those of other samples (liver, heart, intestine, and skeletal muscle). These results indicated that bloodstains mixed with brain tissue were clearly distinguishable from others. Thus, in forensic practice, measurement of S-100 protein or the ratio of S-100 protein to total protein is useful to identify blood and bloodstains containing brain tissue.

Dexamethasone increases beta 2-adrenoceptor-regulated phosphatidylcholine secretion in rat alveolar type II cells

Insufficient production of pulmonary surfactant in alveolar type II cells is relevant to many lung diseases. To cure its deficiency, glucocorticoid is commonly used in clinical areas. In the present study, we investigated the effect of dexamethasone on the secretion of phosphatidylcholine, a major phospholipid of pulmonary surfactant, in a primary culture of rat alveolar type II cells. Dexamethasone had no effect on the basal secretion rate of phosphatidylcholine. Dexamethasone augmented both the phosphatidylcholine secretion and the cyclic AMP formation increased by terbutaline. Furthermore, dexamethasone increased the number of beta-adrenoceptors and mRNA expression of beta 2-adrenoceptors in type II cells. These findings indicate that dexamethasone increases pulmonary surfactant secretion through an enhancement of beta 2-adrenoceptor gene expression.

Inhibition of glycine currents by dextromethorphan in neurones dissociated from the guinea-pig nucleus tractus solitarii

1. The effect of dextromethorphan (DM) on the current induced by glycine in acutely dissociated nucleus tractus solitarii (NTS) neurones of guinea-pigs was studied by use of the whole-cell patch clamp technique. The effect of DM on gamma-aminobutyric acid (GABA)-induced currents (IGABA) was also examined. 2. DM inhibited 30 microM glycine-induced current (IGly), without affecting the current caused by 30 microM GABA. The action of DM was concentration-dependent, with a maximum effect at 100 microM, and reversible. The half-maximum inhibitory concentration (IC50) of DM was 3.3 microM, about 85 times higher than that of strychnine. 3. DM 3 microM shifted the concentration-response curve for glycine to the right without affecting the maximum value. DM 10 microM shifted the curve even more to the right, although it was not a parallel shift. Strychnine at a concentration of 0.1 microM shifted the curve for glycine in a nearly parallel fashion. 4. The effect of 10 microM DM was slightly weak voltage-dependency, but the lower concentration of DM, 3 microM, inhibited IGly equally at -50 mV and +50 mV. The effect of 3 microM DM on IGly showed no use-dependence. Blockade by strychnine 0.1 microM showed no voltage- or use-dependence. 5. The results indicate that DM inhibits IGly in single neurones of NTS, and further suggest that DM at a low concentration may act on the glycine receptor-ionophore complex, but not on the Cl channel of the complex. However, a relatively high concentration of DM may at least partly affect the Cl- channel of the complex.

A medico-legal approach to the myocardial changes caused by transthoracic direct current countershock

The myocardial damage caused by transthoracic direct current countershock was evaluated serologically and histologically. Countershock energy of between 12 and 240 watt-second (ws) discharge was given to rabbits. Total creatine kinase (total CK) and creatine kinase-MB isozyme (CK-MB) activities in plasma were increased after the countershock, with peak values averaging 5690 IU/L (total CK) and 35 IU/L (CK-MB) within 6 h, whereas the CK-MB activity of a rabbit subjected to countershock in the femoral region was within normal range of less than 3 IU/L. Histologically, epicardial alteration was found in electrode-shaped areas which confined to the superficial epicardium in all rabbits. The heart from rabbits that died within a few minutes after countershock showed epicardial alteration in right and left ventricles, and subendocardial alteration with focal hemorrhage was evident in the left ventricle. Subendocardial necrosis and interstitial edema were also revealed in the left ventricle 72 h after countershock. These myocardial damages appeared in the transthoracic pathway between the electrodes. Thus, we conclude that the myocardial damage caused by countershock is distinguishable from heart disease in terms of the characteristic areas and measuring CK levels.