Intrathecal Nicorandil and Small-Dose Morphine Can Induce Spastic Paraparesis After a Noninjurious Interval of Spinal Cord Ischemia in the Rat

We investigated the interaction between nicorandil, a K(+)ATP channel opener, and morphine on motor function after a noninjurious interval of spinal cord ischemia in the rat. Spinal ischemia was induced by aortic occlusion for 6 min with a balloon catheter in Sprague-Dawley rats. All animals received intrathecal (IT) injection of morphine (1-60 microg) 1 h after ischemia. In addition to IT injection of morphine, group M (control), group MN (combination of morphine and nicorandil), and group MNG (combination of morphine, nicorandil, and glibenclamide) received IT saline, nicorandil (10 microg), and both glibenclamide (10 microg) and nicorandil (10 microg) after 150 min of reperfusion, respectively. A quantal bioassay for the effect of IT morphine on neurological function after ischemia was performed to calculate 50% effective dose values (ED50) for inducing paraparesis at 3 h of reperfusion. The ED50 in group M and group MN was 15.1 +/- 4.9 microg and 2.9 +/- 1.0 microg of IT morphine, respectively (P < 0.05). In Group MNG, the dose-response curve shifted back to the right and the ED50 for inducing paraparesis was 11.6 +/- 4.7 microg of IT morphine. The present study demonstrates that IT small-dose morphine combined with nicorandil induces spastic paraparesis after noninjurious interval of spinal cord ischemia in the rat.

Mu and delta, but not kappa, opioid agonists induce spastic paraparesis after a short period of spinal cord ischaemia in rats

BACKGROUND

Intrathecal (IT) morphine given after a short interval of aortic occlusion in a rodent model induced transient spastic paraparesis via opioid receptor-predicted actions in spinal cord. To determine the role(s) of spinal opioid receptor subtypes we investigated whether IT administration of various selective opioid receptor agonists can induce paraparesis following a short period of spinal cord ischaemia in rats.

METHODS

In Sprague-Dawley rats implanted with an IT catheter, spinal cord ischaemia was induced for 6 min using an intraaortic balloon. Mu ([D-Ala2, N-Me Phe4, Gly-ol5] enkephalin), kappa (U50488H) or delta ([D-Pen(2,5)] enkephalin) selective agonists were injected intrathecally 30 min after reperfusion. A separate group of animals was used to investigate the dose-response effect on this motor dysfunction. For this purpose, three doses of mu, kappa, or delta agonists were injected intrathecally after ischaemia. After IT injection, recovery of motor function was assessed periodically using the motor deficit index (0=complete recovery; 6=complete paraplegia).

RESULTS

IT administration of mu and delta but not kappa agonists produced dose-dependent effects in the induction of spastic paraparesis. In addition, this spasticity induced by IT mu and delta agonists was reversed completely by IT naloxone and naltrindole, respectively.

CONCLUSION

These results suggest that the effect of various opioids on motor function after a short period of spinal cord ischaemia depends upon individual opioid receptor subtypes.

Unanticipated full stomach at anesthesia induction in a type I diabetic patient with asymptomatic gastroparesis

We encountered a case of unanticipated full stomach at anesthesia induction, despite a 12-h fasting period, in a type I diabetes patient with diabetic neuropathy presenting for elective vitrectomy for proliferative diabetic retinopathy. The patient had ingested seaweed 24 h prior to the surgery, and it was later found in the aspirated gastric content. Gastrointestinal dysfunction due to diabetic neuropathy and the high fiber content of the ingested seaweed are the probable causes of unanticipated full stomach in our case.

Changes in Helicobacter pylori status in patients with rheumatoid arthritis under non-steroidal anti-inflammatory drugs

BACKGROUND

The role of Helicobacter pylori infection in rheumatoid arthritis (RA) patients during treatment with non-steroidal anti-inflammatory drugs (NSAID) is still unclear.

METHODS

By means of endoscopy and biopsy, gastroduodenal lesions and H. pylori status were repeatedly examined in 88 RA patients at intervals ranging from 26 to 49 months. Histology and culture were applied to determine H. pylori status. Serial changes in gastroduodenal lesions and histologic score for mucosal atrophy were compared among groups classified by initial and second H. pylori status.

RESULTS

There were 28 patients with continuously positive H. pylori infection (CP group), 33 patients with continuously negative H. pylori infection (CN group), 7 patients in whom H. pylori status became negative (PN group), and 20 patients in whom H. pylori status could not be determined (UD group). Age, duration and species of NSAID, disease activity of RA, gastroprotective drugs applied and the prevalence of gastroduodenal mucosal lesions were not different among the groups at either the initial or the second examination. In the PN group, the score for mucosal atrophy at the second examination was significantly lower than at the initial examination, whereas no difference was found for the CP, CN and UD groups. Overall, histologic score for mucosal atrophy was higher in H. pylori-positive patients than in H. pylori-negative patients at both initial and second examination.

CONCLUSIONS

In RA patients using NSAIDs, H. pylori infection may not affect the course of gastroduodenal lesions and activity of RA, but the infection contributes to mucosal atrophy.

Inflammatory myoglandular colorectal polyps: a case series of nine patients

Inflammatory myoglandular polyp is an uncommon benign colorectal polyp. We treated nine cases of histologically verified inflammatory myoglandular polyp. The polyps were identified as a pedunculated protrusion located in the distal part of the large intestine. On colonoscopy, eight polyps had a smooth, spherical, and hyperemic surface, accompanied by a patchy mucous exudate. Magnification endoscopy revealed a rugged surface composed of smooth nodules. These colonoscopic findings corresponded to hyperplastic glands with occasional cystic dilation and inflamed stroma with proliferation of smooth-muscle fibers. Inflammatory myoglandular polyp appears to be a distinctive clinical entity, with a unique appearance on colonoscopy.

Intrathecal administration of morphine, but not small dose, induced spastic paraparesis after a noninjurious interval of aortic occlusion in rats

We sought to investigate the dose-response relationship for the effect of intrathecal morphine on the transient spastic paraparesis after short-lasting spinal ischemia in rats. Spinal ischemia was induced by aortic occlusion for 6 min with a balloon catheter in rats previously implanted with an intrathecal catheter for drug delivery. After ischemia, the animals were allowed to recover, and 3, 10, or 30 microg of morphine or saline was injected intrathecally at 30 min after reperfusion. In a separate group, the quantal bioassay for the effect of intrathecal morphine on neurological function after ischemia was performed to calculate 50% effective dose values for inducing paraparesis at 2 h of reperfusion. Subsequently, histopathology of the spinal cord was assessed at 48 h of reperfusion. Intrathecal injection of 30 or 10 micro g of morphine, but 3 micro g of neither morphine nor saline, caused a progressive development of hindlimb spasticity. The 50% effective dose values for inducing paraparesis were 16.1 +/- 1.5 microg in assessing behavioral analysis at 2 h after intrathecal morphine. Histopathological analysis of spinal cords in the 30- microg group revealed the presence of dark-staining alpha-motoneurons in lumbosacral segments. We conclude that spinal administration of a large dose of morphine after transient aortic occlusion may be associated with a potential risk of paraparesis and the corresponding development of neurological dysfunction. Careful attention should be paid when intrathecal morphine is used for pain control after thoracoabdominal aortic aneurysm repair.

IMPLICATIONS

Spinal administration of large-dose morphine after transient aortic occlusion may be associated with a potential risk of irreversible spinal neuronal degeneration and the corresponding development of neurological dysfunction.

Propofol reduces spinal motor neuron excitability in humans

IMPLICATIONS

We investigated in humans whether changes in spinal motor neuron excitability correlate with the predicted propofol concentration (Cpt) achieved by a target-controlled infusion system. Propofol suppressed F-wave persistence in a Cpt-dependent manner, indicating that propofol depresses spinal motor neuron excitability at clinically relevant concentrations.

Helicobacter pylori infection in rheumatoid arthritis: effect of drugs on prevalence and correlation with gastroduodenal lesions

OBJECTIVE

The aim of this study was to investigate the impact of Helicobacter pylori infection on clinical features in patients with rheumatoid arthritis (RA) under medication with non-steroidal anti-inflammatory drugs.

METHODS

One hundred and eighty-four patients with RA were tested for the presence of H. pylori infection. Clinical features and gastroduodenal lesions were compared between H. pylori-positive and -negative patients.

RESULTS

One hundred and thirteen patients were positive and 71 patients were negative for H. pylori. The age, severity of RA, prevalence of gastrointestinal symptoms and gastroduodenal lesions and the class of gastroprotective drugs were not different between the two groups. Reflux oesophagitis was less frequent and sulphasalazine was less frequently administered in the H. pylori-positive group.

CONCLUSIONS

The severity of RA, prevalence of gastroduodenal lesions other than reflux oesophagitis and the application of gastroprotective drugs do not seem to depend upon H. pylori infection in RA patients. Sulphasalazine may be protective against H. pylori infection.

Electrolytic partial fluorination of organic compounds. 55. Highly regio- and stereoselective anodic monofluorination of 2,3-dihydrochroman-4-one and chromone derivatives

Anodic monofluorination at the position alpha to the oxygen atom of the (E)-3-benzylidene-2,3-dihydrochroman-4-one derivatives was successfully carried out to provide the corresponding 2-fluorochromanones selectively. This is the first regioselective electrochemical fluorination of fused-type, oxygen-containing heterocyclic compounds. Anodic fluorination of a chromone derivative also gave a similar fluorinated chromanone stereoselectively.

Difference in degree of mucosal atrophy between elevated and depressed types of gastric epithelial tumors

BACKGROUND

The significance of atrophy in the background mucosa and Helicobacter pylori infection in the morphogenesis of gastric epithelial tumors has not yet been investigated.

METHODS

The degree of mucosal atrophy, as determined by a histological analysis and the serum pepsinogen (PG) levels, and H. pylori status were investigated in patients with elevated adenoma (EA group; n = 40), elevated early cancer of intestinal type (ECI group; n = 30), depressed early cancer of intestinal type (DCI group; n = 37) and depressed early cancer of diffuse type (DCD group; n = 33), and the findings were then compared to those in 91 controls.

RESULTS

At all sites of the stomach, the histologic score of atrophy was higher in the EA group and in the ECI group than in the controls. In the DCI group, the histologic score of atrophy in the antrum was higher than in the controls, but no such difference in the score was found in the DCD group. The PG I/II ratios in the EA, ECI and DCI groups were significantly lower than in the controls, and the value was also different between the ECI and DCI groups. While H. pylori prevalence was higher in all groups than in the controls, a logistic regression analysis which included the grade of atrophy as a determinant revealed the infection to be an independent associated factor for the DCD group.

CONCLUSIONS

The difference in the background mucosal atrophy seems to contribute to different macroscopic types in gastric epithelial tumors. This seems to be the case especially for cancer of intestinal type.

Electroytic partial fluorination of organic compounds. 52. Regio- and diastereoselective anodic fluorination of thiazolidines

Anodic fluorination of N-benzoyl, N-acethyl-, and N-formylthiazolidine derived from L-cysteine was carried out in dimethoxyethane (DME) and acetonitrile containing various supporting fluoride salts using an undivided cell. Highly regioselective fluorination proceeded to provide the corresponding 5-monofluorinated thiazolidine derivatives in good yields in DME, and the diastereoselectivitiy was moderate to high regardless of the supporting fluoride salts. The diastereoselectivitiy of the fluorination was greatly affected by the bulkyness of the subsitituent on the nitrogen atom, and N-benzoylthiazolidine gave much higher diastereoselectivity compared with N-formyl derivative. The fluorination of the thiazolidines was not achieved by commercially available fluorinating reagents such as N-fluoropyridinium salts.

Electrolytic partial fluorination of organic compounds. 54. Anodic mono- and trifluorination of thiochroman-4-one derivatives and the factors affecting product selectivity

Anodic fluorination of (E)-3-benzylidene-2,3-dihydrothiochroman-4-one and 3-benzyl-1-thiochromone derivatives under a variety of electrolytic conditions was found to provide selectively or exclusively the same fluorinated products: (E)-3-benzylidene-2,3-dihydro-2-fluorothiochroman-4-ones. In addition, di- and trifluorinated derivatives were also obtained depending on the starting heterocycles and electrolytic conditions. The factors affecting the product selectivity were also examined.

The interaction of somatosensory evoked potentials between mixed-sensory nerves and sensory-sensory nerves

The interactions between two different nerves occur by occlusion or inhibition when two nerves share the synaptic connections. In our previous study, we have demonstrated that posterior tibial nerve and peroneal nerve sensory inputs interact with each other, i.e., preceding stimulus to one nerve suppresses the somatosensory evoked potential (SEP) of the other nerve when two stimuli are delivered in close sequence. The course of suppression follows two phases; the first one occurring at short interstimulus intervals (ISIs) of the two nerves less than 10 msec, and the second one being at around 30 msec ISI after partial recovery following the first suppression phase. In that study, we have postulated that the second phase suppression was equivalent for the movement induced "gating" mechanism. In this study, the interactions of mixed nerve (posterior tibial) and sensory nerve (sural), and also sensory (sural) and sensory (saphenous) nerves were examined. We found that the mixed nerve (posterior tibial) exerted similar dual phases of suppression (as was seen in posterior tibial--peroneal nerve study) on to the sural nerve SEP, but the reverse was not true. Also the sensory and sensory nerve interactions were not mutually equal; the sural nerve stimulation caused two phases suppression but the reverse condition did not show significant suppression. The above findings suggest (1) interference input from the sensory nerve to the mixed nerve is much weaker than the reverse condition, and (2) sensory and sensory nerves interactions occur but two nerves' interference inputs are not necessarily equal and one could dominant the other.

A study of mismatch negativity in newborns

BACKGROUND

Although newborns are presumed to have cognitive ability, studies on the objective cognitive ability of neonates are making little progress.

METHODS

We gave auditory and visual stimuli to newborns whose conceptional age ranged from 35 to 43 weeks and recorded the mismatch negativity (MMN) that is said to reflect the process by which stimuli are detected automatically. We compared the waveform and latency of the MMN.

RESULTS

The mismatch negativity waveform in newborns was similar to that of adults. The MMN latency tended to shorten with an advance in conceptional age and was especially shortened between 36 and 37 weeks of fetal life. In some newborns whose clinical course indicated a possibility of their having cognitive dysfunction, the MMN latency was prolonged.

CONCLUSIONS

Newborns also have cognitive ability and MMN is useful for objectively evaluating the cognitive ability in newborns.

[Hopkins syndrome: oral prednisolone was effective for the paralysis]

We describe here a 5-year-old girl who presented flaccid paralysis of the left upper limb after recovery from bronchial asthma. T2-weighted magnetic resonance imaging of the cervical cord revealed a focal high intensity area in the left anterior horn at the C6-C7 level. She was treated with oral prednisolone, and paralysis resolved within two months. Thirty cases of Hopkins syndrome have been reported so far, but its cause remains unknown. Early administration of prednisolone might ameliorate paralysis in this syndrome.

Electrolytic partial fluorination of organic compounds. 42.(1) marked solvent effects on regioselective anodic monofluorination of 4-oxo-2-pyrimidyl sulfides

Regioselective anodic monofluorination of 4-oxo-2-pyrimidyl sulfides was investigated under various electrolytic conditions. Anodic fluorination was successfully carried out using Et(4)NF.4HF in dimethoxyethane (DME) to provide the corresponding alpha-fluorinated products in good yields. In contrast, acetonitrile (MeCN) was not suitable for the anodic fluorination due to the severe anode passivation during the electrolysis. A mixed solvent of DME and MeCN was found to be also effective for the fluorination, and the product yield increased with an increase of the ratio of DME to MeCN. The superiority of DME can be explained mainly in terms of the suppression of the anode passivation and enhancement of the nucleophilicity of the fluoride ions. Such marked solvent effects on the anodic fluorination were discussed in detail.

Motor-evoked potentials in a child recovering from transverse myelitis

We describe a 13-year-old female, with an inability to walk because of transverse myelitis, who demonstrated progressive recovery of both motor function and motor- evoked potentials (MEP). At 4 weeks after onset, amplitudes of MEP were decreased, latencies were prolonged, and cortical somatosensory-evoked potentials (SEP) were absent. At 6 and 12 weeks, MEP revealed progressively higher amplitudes and shorter latencies. SEP also recovered. MEP and SEP recovery paralleled clinical recovery. MEP in response to transcranial magnetic stimulation may provide guidance regarding recovery from spinal cord disorders in children.

[Diagnosis of ulcerative colitis--barium enema examination]

Barium enema is useful especially for differential diagnosis of right sided type or segmental type of ulcerative colitis from other inflammatory bowel diseases. Compared with endoscopical examination, it provides more objective informations about the range of affected colon which is necessary for the choice of treatment strategy to the reluctant case. However, as preparation procedures may cause aggravation of ulcerative colitis, an unnecessary barium study should be avoided. Even the case in remission stage, it is advisable to add 40 to 60 mg of water-soluble predonisolone to barium solution. Roentogenographic diagnosis of ulcerative colitis is not difficult, in so far as two major points are properly evaluated. The first is the presence or absence of haustration, and the second is mucosal surface of the colon, namely, multiple ulcers or erosions distributing diffusely and continuously in active stage, or granular mucosa and disarray of network pattern of colonic mucosa in remission stage.

Helicobacter pylori and mucosal atrophy in patients with gastric cancer: a special study regarding the methods for detecting Helicobacter pylori

We assessed the sensitivities of several methods for detecting Helicobacter pylori (culture, histology, rapid urease test, and serology), and evaluated the H. pylori positivity considering the degree of atrophy in the background mucosa in 202 gastric cancer patients and 101 controls. The positivity of H. pylori determined by culture (81%) was significantly higher than that determined by serology (62%) in gastric cancer patients (P < 0.001). The positivities of H. pylori determined by biopsy and/or serology in intestinal (84%) and diffuse (95%) types of gastric cancer were higher than that observed in controls (54%) (P < 0.001). Intestinal-type gastric cancer tended to occur in the atrophic mucosa, in which H. pylori positivity was not different from that in controls after adjusting for the degree of atrophy, whereas diffuse-type gastric cancer was observed more often in the nonatrophic mucosa, in which H. pylori positivity was higher than that in controls even after adjusting for the degree of atrophy.

Lack of tolerance in peripheral opioid analgesia in mice

We recently developed a sensitive peripheral analgesic test in mice. Bradykinin, a representative pain-producing substance, when given subcutaneously through a polyethylene tube into the plantar of the limb connected to a transducer, induced a flexor reflex response, in a dose dependent manner. When morphine, a mu-opioid receptor agonist, was added to the plantar through another polyethylene tube, bradykinin-induced responses were completely abolished in a naloxone-reversible manner. These peripheral analgesic effects were also observed with DAMGO, another mu-opioid receptor agonist, and U-69,593, a kappa-opioid receptor agonist, but not DSLET, a delta-opioid receptor agonist. When morphine was given subcutaneously to the back, a potent analgesia in the tail pinch test was observed. Repeated administrations of morphine once per day for 5 days showed a marked tolerance or reduction in morphine analgesia on the 6th day, while there was no significant reduction in the peripheral analgesia of morphine. These findings suggest that tolerance to morphine analgesia is mediated through synaptic plasticity in the central nervous system, but not through a receptor desensitization at the level of the single cell.