Degradation pathways of cyclic alkanes in Rhodococcus sp. NDKK48.

The degradation pathways for cyclic alkanes (c-alkanes) in Rhodococcus sp. NDKK48 were investigated. Strain NDKK48 used dodecylcyclohexane as a sole carbon and energy source, and five metabolites in the dodecylcyclohexane degradation pathway were detected by gas-chromatography/mass spectra. The metabolites were identified as cyclohexanecarboxylic acid, cyclohexylacetic acid, 1-cyclohexene-1-acetic acid, 4-dodecylcyclohexanol, and 4-dodecylcyclohexanone. The strain degrades dodecylcyclohexane via a ring oxidation pathway and an alkyl side chain oxidation pathway. Cyclohexanecarboxylic acid was further oxidized to muconic acid via 1-cyclohexene-1-carboxylic acid and benzoic acid, and the muconic acid was finally used by strain NDKK48 for growth. Methylcyclohexane and cyclohexane were co-oxidized with hexadecane by strain NDKK48. Methylcyclohexane was degraded via a ring oxidation pathway, and the degradation pathway contained part of the Baeyer-Villiger oxidation for ring cleavage. Cyclohexane was also degraded by the same pathway as methylcyclohexane. Thus, strain NDKK48 has two pathways for the complete degradation of c-alkanes.

Differential screening-selected gene aberrative in neuroblastoma protein modulates inflammatory pain in the spinal dorsal horn.

Differential screening-selected gene aberrative in neuroblastoma (DAN) belongs to a novel gene family that includes the Xenopus head-inducing factor, Cerberus and the dorsalizing factor, Gremlin. It has been suggested that members of this family control diverse processes in growth, development and the cell cycle.Here, we demonstrate that the DAN protein is produced in the small neurons of the dorsal root ganglion and is transported to the nerve terminals in the spinal dorsal horn in adult rats. Furthermore, intrathecal injection of an antibody to the DAN protein suppressed inflammatory pain caused by the introduction of complete Freund's adjuvant or carrageenan into the rat hindpaw. The amount of mRNA for DAN in dorsal root ganglion neurons and of its expressed protein in the spinal dorsal horn were both increased in inflammatory models.Together, these data suggest that the DAN protein may be a novel neuromodulator in primary nociceptive nerve fibers.

Gut transit time after ileal pouch-anal anastomosis using a radiopaque marker.

PURPOSE: The aim of this study was to determine the contribution of gastrointestinal motility to bowel function and the pathogenesis of pouchitis after ileal pouch-anal anastomosis. METHODS: Gastrointestinal transit time was assessed by a radiopaque marker technique in 32 patients with ulcerative colitis. RESULTS: Small intestinal transit time and pouch emptying time were 4.1 +/- 2 hours and 4.1 +/- 2.5 hours, respectively. There was no significant difference in pouch emptying time between patients with and without pouchitis. When only patients with acute pouchitis that responded to metronidazole were analyzed, there was a trend toward a prolonged pouch emptying time compared with those without pouchitis (P = 0.095). Whole gut transit time was inversely correlated with 24-hour stool frequency in patients without pouchitis (r = -0.63, P < 0.005). In the analysis of regional transit time, only small intestinal transit time was inversely correlated with 24-hour stool frequency (r = -0.472, P < 0.05). Significant prolongation of small intestinal transit time was demonstrated in patients over a period of 41 months (the median time) after ileostomy closure compared with those whose pouches had been functioning for 6 to 41 months (5.4 +/- 1.7 hours vs. 3.1 +/- 1.3 hours, P < 0.005). CONCLUSIONS: There was an association between small intestinal motility and bowel frequency. Further investigation is necessary in the pathogenesis of acute pouchitis regarding the relationship between delayed pouch emptying and subsequent development of mucosal inflammation.

Spinal N-acetyl-alpha-linked acidic dipeptidase (NAALADase) inhibition attenuates mechanical allodynia induced by paw carrageenan injection in the rat.

N-Acetylated-alpha-linked acidic dipeptidase (NAALADase) hydrolyzes N-acetyl-aspartyl-glutamate (NAAG) to liberate N-acetyl-aspartate and glutamate. NAAG is a putative neurotransmitter and acts as a mixed agonist/antagonist on N-methyl-D-aspartate (NMDA) receptors and acts as an agonist on the metabotropic glutamate receptor 3 (mGluR3). In the present study, we examined the role of spinal NAALADase in the maintenance of mechanical allodynia induced by carrageenan injection, skin incision and mild thermal injury using 2-(phosphonomethyl)pentanedioic acid (2-PMPA), a specific NAALADase inhibitor, in rats. Mechanical allodynia was induced by injection of 2 mg carrageenan into the paw (carrageenan model), by creating a 1-cm longitudinal skin incision of the plantar aspect of the foot (post-operative model), or by application of thermal stimulation (52.5 degrees C) for 45 s to the hind paw (mild thermal injury model). 2-PMPA was administered intrathecally at the time when the maximum mechanical allodynia occurred. Mechanical allodynia was assessed by the measurement of mechanical threshold using von Frey filaments. The mechanical threshold was measured 5, 15, 30, 60 and 90 min after the drug administration. In the carrageenan model, 100 microg of 2-PMPA attenuated the level of mechanical allodynia. 2-PMPA had no effect on the level of mechanical allodynia in both the post-operative pain model and the mild thermal injury model. These data suggested that the inhibition of spinal NAALADase alleviated mechanical allodynia induced by paw carrageenan injection.

Primary leptomeningeal lymphoma.

Primary leptomeningeal lymphoma is a rare disorder, and the neuroradiological characteristics or the complication of this rare disorder have not been well reported. We reported herein a patient with a primary leptomeningeal lymphoma who has complication with subdural hematoma. The patient complained of headache and vomiting. Neurological examination revealed progressive cranial nerve palsy. Cerebrospinal fluid examination disclosed monoclonal proliferation of atypical B-lymphocytes. Cranial computed tomographic scans showed a left frontal mass with convex form to the brain parenchyma. T1-weighted magnetic resonance (MR) images disclosed subacute subdural hematoma. However, proton-weighted MR images showed high signal intensity in subarachnoid space, which suggested leptomeningeal lymphoma. He underwent craniotomy, and the diagnosis of leptomeningeal lymphoma complicated with subdural hematoma was confirmed. Systemic examinations disclosed no lymphomatous lesions except for leptomeningus, and the diagnosis of primary leptomeningeal lymphoma was established. We suggested that subdural hematoma was associated with primary leptomeningeal lymphoma in this patient. Cerebrospinal fluid examination and proton-weighted MR imaging should be performed when progressive neurological abnormalities are found in patients with subdural hematoma.

Antagonism of ORLI receptor produces an algesic effect in the rat formalin test.

The authors investigated the role of endogenously released nociceptin (also known as orphanin FQ) spinal and supraspinal nociceptive transmission during the rat formalin test by examining the effect of intrathecal and intracerebroventricular injection of J-113397, a non-peptidyl ORL1 receptor selective antagonist. When J-113397 was injected intrathecally or intracerebroventricularly 10 min before the formalin injection, it enhanced the agitation behavior induced by paw formalin injection. This suggested that paw formalin injection induced nociceptin release in the spinal cord and the supraspinal brain sites, that this endogenously released nociceptin produced an analgesic effect and that J-113397 antagonized this analgesic effect of nociceptin and produced an algesic effect in the rat formalin test.

Involvement of PACAP receptor in primary afferent fibre-evoked responses of ventral roots in the neonatal rat spinal cord.

The role of PACAP receptor in nociceptive transmission was investigated in vitro using maxadilan, a PACAP receptor selective agonist and max.d.4, a PACAP receptor selective antagonist. Potentials, from a ventral root (L3 - L5) of an isolated spinal cord preparation or a spinal cord - saphenous nerve - skin preparation from 0 - 3-day-old rats, were recorded extracellularly. In the isolated spinal cord preparation, single shock stimulation of a dorsal root at C-fibre strength induced a slow depolarizing response lasting about 30 s (slow ventral root potential; slow VRP) in the ipsilateral ventral root of the same segment. Bath-application of max. d.4 (0.01 - 3 microM) inhibited the slow VRP in a concentration-dependent manner. In the spinal cord - saphenous nerve - skin preparation, application of capsaicin (0.1 microM) to the skin evoked a depolarization of the ventral root. This response was also depressed by max.d.4 (1 microM). Application of maxadilan evoked a long-lasting depolarization in a concentration-dependent manner in the spinal cord preparation. In the presence of max.d.4 (0.3 microM), the concentration response curve of maxadilan was shifted to the right. Reverse transcription-polymerase chain reaction (RT - PCR) experiments demonstrated the existence of PACAP receptor and VPAC(2) receptor in the neonatal rat spinal cord and [(125)I]-PACAP27 binding was displaced almost completely by maxadilan and max.d.4, but not by vasoactive intestinal peptide (VIP). These data indicate that PACAP receptor is dominantly distributed in the neonatal rat spinal cord. The present study suggests that PACAP receptor may play an excitatory role in nociceptive transmission in the neonatal rat spinal cord.

Inhibition of spinal N-acetylated-alpha-linked acidic dipeptidase produces an antinociceptive effect in the rat formalin test.

N-acetyl-aspartyl-glutamate is a putative neurotransmitter and acts as a weak agonist at the N-methyl-D-aspartate receptor. N-acetyl-aspartyl-glutamate also acts as an agonist at the metabotropic glutamate receptor 3. N-acetyl-aspartyl-glutamate is hydrolyzed by N-acetylated-alpha-linked acidic dipeptidase to liberate N-acetyl-aspartate and glutamate. Recently, a specific inhibitor of N-acetylated-alpha-linked acidic dipeptidase, 2-(phosphonomethyl)pentanedioic acid, has been reported. In the present study, we examined the effect of i.t. administered 2-(phosphonomethyl)pentanedioic acid in the rat formalin test (a model of inflammatory pain) and the rat hot plate test. In the formalin test, drugs were administered 10min before (pre-treatment study) or 7min after (post-treatment study) the formalin injection. The paw formalin injection induces biphasic flinching (phase 1: 0-2min; phase 2: 10-60min) of the injected paw. In the pre-treatment study, i.t. administered 2-(phosphonomethyl)pentanedioic acid depressed both phases 1 and 2 flinching behavior in a dose-dependent manner but 2-(phosphonomethyl)pentanedioic acid had no effect on the flinching behavior in the post-treatment study. In the pre-treatment study, the potency of 2-(phosphonomethyl)pentanedioic acid in depressing the phase 2 response is greater than that in depressing the phase 1 response. Intrathecal injection of 2-(phosphonomethyl)pentanedioic acid had no effect in the hot plate test. We suggest that N-acetylated-alpha-linked acidic dipeptidase plays an important role in spinal nociceptive transmission and that inhibition of spinal N-acetylated-alpha-linked acidic dipeptidase produces an antinociceptive effect during the rat formalin test but not during the hot plate test.

Generation of pro-inflammatory and anti-inflammatory cytokines in the gut in zymosan-induced peritonitis.

In major systemic inflammation such as severe peritonitis, various pro-inflammatory cytokines, such as TNF-alpha, IL-1 beta and IL-6, play important roles in the development of multiple organ dysfunction syndrome (MODS). The purpose of this study was to investigate the outflow of pro-inflammatory and anti-inflammatory cytokines from the efferent mesenteric lymphatic vessels under peritonitis. Mesenteric lymph samples were collected from adult male rats at 2, 4, 6, 8 and 10 hr after an intraperitoneal injection of zymosan at a dosage of 0.1 mg/g (non-lethal dose) or 0.5 mg/g (lethal dose). Blood samples were obtained at 10 hr after zymosan administration. The amounts of drained TNF-alpha and IL-6 in the lymph peaked at 2-4 hr and 4-8 hr after zymosan administration, respectively. The amounts of drained IL-10 in the lymph gradually increased until 10 hr. The amounts of drained TNF-alpha and IL-10 in the mesenteric lymph were significantly correlated with the dosage of zymosan. In conclusion, under intraperitoneal inflammation, pro-inflammatory cytokines (TNF-alpha and IL-6) increased in the mesenteric lymph and were drained into circulation. IL-10, one of the anti-inflammatory cytokines, also increased in the mesenteric lymph after several hours' delay and its increase was remarkable in several inflammations. These findings suggested that the gut might be one of the pro-inflammatory and anti-inflammatory cytokine-generating organs under peritonitis. The lymph-drained amounts of each cytokine under peritonitis are considered to differ with the time or severity of inflammation, which may cause different conditions in patients due to the imbalance of pro-inflammatory and anti-inflammatory cytokines.

Anti-allodynic effects of oral COX-2 selective inhibitor on postoperative pain in the rat.

PURPOSE: To examine the effect of a cyclooxygenase (COX)-2 inhibitor on the maintenance of mechanical allodynia induced by skin incision (an animal model of postoperative incident pain) in the rat. Also, to compare the effect of a COX-2 inhibitor with that of a nonselective COX-1 and COX-2 inhibitor and B2 receptor antagonist. METHODS: A 1 cm longitudinal skin incision was made in the plantar aspect of the foot. JTE522 (1-100 mg x kg(-1)), a COX-2 inhibitor, indomethacin (1-30 mg x kg(-1)), a nonselective COX-1 and COX-2 inhibitor, or FR173657 (10 and 100 mg x kg(-1)), a bradykinin B2 receptor antagonist, was administered orally five minutes after the end of the surgery. The level of mechanical allodynia was assessed by measuring the frequency of foot withdrawal in response to the application of a 12.5 g on Frey filament at 2, 4, 6, 8 and 24 hr after the drug administration. RESULTS: Oral administration of JTE522 or indomethacin attenuated the maximum response frequency in a dose-dependent manner at a dose between 1 and 30 mg x kg(-1) (P < 0.05). Oral FR 173657, (100 mg x kg(-1)), had no effect on the maximum response frequency. CONCLUSION: These data indicated that a COX-2 inhibitor attenuated the level of mechanical allodynia in the rat model of postoperative pain.

A brief course of colon preparation with oral antibiotics.

We carried out a prospective clinical trial of colon preparation with a regimen of oral antibiotics starting on the day before surgery. The patients were assigned to one of two groups consisting of either a mechanical preparation alone group (group 1, 45 cases) or a mechanical bowel preparation with oral antibiotics group (group 2, 38 cases). Group 2 received kanamycin and metronidazole three times on the day before surgery. Cefmetazole was administered for 3 consecutive days as prophylaxis in both groups. In a study using intraoperative mucosal swabs, the rates of group 2 patients with cultures yielding anaerobes or Gram-negative bacteria were significantly lower than those of group 1. There were no significant differences in the rates of patients with cultures yielding fungi or Gram-positive organisms. The positive culture rate in the peritoneal fluid of group 1 was also higher than that of group 2 (40%, 16%, P < 0.05). The surgical site infection rate was 18% in group 1 and 13% in group 2. Organisms isolated from the sites of postoperative infections were not identical with those from the peritoneal fluid. This relatively brief course preparation minimized the emergence of resistant strains. However, in spite of the colonic bacterial burden and the intraoperative inoculation in the patients with mechanical cleansing alone, their incidence of subsequent infections was comparable to that of patients who were administered oral antibiotics provided that the prophylactic antibiotic was administered for 3 days after surgery.

Baicalin, the predominant flavone glucuronide of scutellariae radix, is absorbed from the rat gastrointestinal tract as the aglycone and restored to its original form.

When baicalin was orally administered to conventional rats, it was detected in their plasma for 24 h after administration, but baicalein, the aglycone of baicalin, was not detected. However, when baicalin was given to germ-free rats, only a small amount of baicalin was detected in their plasma within 2 h after the administration, its AUC0-lim (the area under the concentration-time curve from 0 to last determination time) being 12.0% of that in conventional rats. Subsequently, a considerable amount (55.1 +/- 6.2%) of baicalin was recovered from the gastrointestinal tract even 4 h after administration. When baicalein was orally administered to conventional rats, however, baicalin appeared rapidly in their plasma at an AUC0-lim value similar to that obtained after oral administration of baicalin, despite the absence of baicalein in plasma. When intestinal absorption was evaluated by the rat jejunal loop method, baicalein was absorbed readily, but only traces of baicalin were absorbed. Moreover, in conventional rats a small amount (13.4 +/- 3.1%) of baicalin and an appreciable amount (21.9 +/- 3.4%) of baicalein were recovered from the gastrointestinal tract even 4 h after oral administration of baicalin, but only a small amount (3.93 +/- 1.43%) of baicalein was detected in the intestinal tract 1 h after administration of baicalein. Baicalin was transformed to baicalein readily by the rat gastric and caecal contents. When baicalin was administered orally to conventional rats, an appreciable amount of baicalein was recovered in their gastrointestinal tracts. Moreover, baicalein was efficiently conjugated to baicalin in rat intestinal and hepatic microsomes. These results indicate that baicalin itself is poorly absorbed from the rat gut, but is hydrolysed to baicalein by intestinal bacteria and then restored to its original form from the absorbed baicalein in the body.

The role of the spinal opioid receptor like1 receptor, the NK-1 receptor, and cyclooxygenase-2 in maintaining postoperative pain in the rat.

UNLABELLED: Postoperative incident pain is not easily treated with opioids. Mechanical hyperalgesia induced by skin incision in rats is one of the animal models of postoperative incident pain. It is thought that mechanical hyperalgesia is maintained by the sensitization of spinal dorsal horn neurons. The NK-1 receptor, the opioid receptor like1 (ORL1) receptor, and cyclooxygenase (COX)-2 reportedly are involved in the development of spinal sensitization. In this study, we clarified the role of the NK-1 receptor, the ORL1 receptor, and COX-2 in the maintenance of mechanical hyperalgesia induced by skin incision. A 1-cm longitudinal incision was made through skin and fascia of the plantar aspect of the right foot in the rat. Four hours after the skin incision, significant mechanical hyperalgesia developed. An ORL1 receptor agonist (nociceptin), NK-1 receptor antagonists (CP-96,345 and FK888), and COX-2 inhibitors (NS398 and JTE522) were administered intrathecally 4 h after the skin incision. An ORL1 receptor agonist and NK-1 receptor antagonists, but not COX-2 inhibitors, significantly attenuated the level of mechanical hyperalgesia induced by the skin incision. These findings suggest that the spinal ORL1 receptor and the NK-1 receptor play an important role in maintaining the mechanical hyperalgesia induced by skin incision. IMPLICATIONS: Intrathecal injection of an NK-1 receptor antagonist and an ORL1 receptor agonist may be effective for the treatment of postoperative incident pain.

Differential effects of intrathecally administered morphine and its interaction with cholecystokinin-B antagonist on thermal hyperalgesia following two models of experimental mononeuropathy in the rat.

BACKGROUND: Cholecystokinin-B receptor activation has been reported to reduce morphine analgesia. Neuropathic pain is thought to be relatively refractory to opioids. One possible mechanisms for a reduced effect of morphine on neuropathic pain is the induction of cholecystokinin in the spinal cord by nerve injury. The authors evaluated the role of the spinal cholecystokinin-B receptor on morphine analgesia in two rat neuropathic pain models: chronic constriction injury and partial sciatic nerve injury. METHODS: A chronic constriction injury is created by placing four loosely tied ligatures around the right sciatic nerve. A partial sciatic nerve injury was created by tight ligation of one third to one half of the right sciatic nerve. All drugs were injected intrathecally 7 and 11 days after the nerve injury. The effect of the drugs was reflected in the degree of paw withdrawal latency to thermal nociceptive stimulation. The paw withdrawal latencies of injured and uninjured paws were measured 5, 15, 30, and 60 min after the drugs were injected. RESULTS: In the chronic constriction injury model, intrathecal morphine increased the paw withdrawal latencies of injured and uninjured paws. PD135158, a cholecystokinin-B receptor antagonist, potentiated the analgesic effect of morphine on injured and uninjured paws. In the partial sciatic nerve injury model, the effect of morphine on the injured paw was less potent than that on the uninjured paw, and PD135158 potentiated the morphine analgesia in the uninjured paw and had only a minor effect on the morphine analgesia in the injured paw. CONCLUSIONS: The effectiveness of morphine for thermal hyperalgesia after nerve injury depends on the type of nerve injury. The role of the cholecystokinin-B receptor in morphine analgesia in thermal hyperalgesia after nerve injury also depends on the type of nerve injury.

The effectiveness of perineal rectosigmoidectomy for the treatment of rectal prolapse in elderly and high-risk patients.

We report herein on the follow-up of ten consecutive patients who underwent perineal rectosigmoidectomy, and discuss the indications, surgical technique, and outcomes of this procedure. The median age of the patients was 79 years, with a range of 26 to 85 years, and eight patients had complicating medical conditions. Of five patients who underwent this procedure for a recurrent prolapse after another type of perineal procedure, four had previously undergone the Thiersch operation combined with the Gant-Miwa technique. The mean length of the excised rectum and sigmoid colon was 22.1 cm. Pain was minimal or absent in all patients and oral intake was commenced after 2 days. There were no mortalities, but anastomotic leakage occurred in one patient. The mean follow-up period was 3.5 years. Only one patient developed recurrent rectal prolapse 24 months after the operation. Of seven patients who underwent concomitant levatoroplasty for incontinence, five became fully continent within 3 weeks after the operation, while the remaining two improved after 2 months. We propose that perineal rectosigmoidectomy is indicated for patients who have suffered an early recurrence of prolapse after another transperineal repair; elderly or high-risk patients with incontinence; male patients; and patients with an incarcerated or gangrenous prolapsed rectal segment.

Effect of nocistatin and its interaction with nociceptin/orphanin FQ on the rat formalin test.

Nocistatin is a 17 amino acid peptide and is processed from prepronociceptin. Nocistatin does not bind to the nociceptin receptor, but nocistatin blocks allodynia induced by nociceptin/orphanin FQ. In this study, we examined the effect of intrathecal nocistatin and its interaction with nociceptin/orphanin FQ in the rat formalin test and the hot plate test. Intrathecal nocistatin attenuated the formalin induced phase 1, but not phase 2, flinching behavior. Coadministration of nocistatin with nociceptin/orphanin FQ did not block the analgesic effect of nociceptin/orphanin FQ. Nocistatin had no effect on the hot plate test. These data suggest that nocistatin produces analgesic effect in the formalin test, but not in the hot plate test, and that the mechanisms underlying the analgesic effect of nocistatin is complex.

Nociceptin/orphanin FQ: role in nociceptive information processing.

Recently, opioid receptor like1 (ORL1) receptor was identified. The ORL1 receptor is a G protein coupled receptor and the sequence of the ORL1 receptor is closely related to that of the opioid receptors. Nociceptin/orphanin FQ has been identified as a potent endogenous agonist of the ORL1 receptor and the sequence of nociceptin/orphanin FQ is closely related to that of dynorphin A. Nociceptin/orphanin FQis not active at the classical opioid receptors, such as mu, kappa and delta receptors. The distribution of prepronociceptin mRNA is distinct from that of the opioid peptide precursor. Mice lacking the ORL1 receptor showed no significant differences in nociceptive threshold compared with wild mice. The role of nociceptin/orphanin FQ on nociceptive transmission is unclear. Intracerebroventricular (i.c.v.) injection of nociceptin/orphanin FQ produced hyperalgesia and allodynia and antagonized morphine analgesia. On the other hand, intrathecal injection of low dose nociceptin/orphanin FQ produces allodynia, but high dose of nociceptin/orphanin FQ produces an analgesic effect. Although we do not fully understand the mechanisms that produce the difference between the effect of i.c.v. injection of nociceptin/orphanin FQ and that of intrathecal injection of nociceptin/orphanin FQ, we believe that spinal ORL1 receptor may be the next receptor which should be targeted by drugs designed for the treatment of pain.

Prediction for the development of postoperative infections in the operation of esophageal cancer compared with gastric surgery.

The purpose of this study was to assess the point at which the postoperative infection has occurred in order to decide upon the proper duration of prophylactic antibiotic use. Another goal of this study was to determine whether prediction for the development of postoperative infections in major surgery such as esophagectomy should be the same as that in routine gastroenterological surgery. Twenty-five patients who underwent transthoracic esophagectomy and 127 patients who underwent gastrectomy were studied. On the third day after gastric surgery, the body temperature of patients who developed an infection was higher than that of the patients who did not develop an infection. The relative changes in peripheral white blood count (WBC), and C-reactive protein (CRP) concentration on the third and fourth days were more predictive of the development of infection than the absolute values. Almost all patients with systemic inflammatory response syndrome (SIRS) on the third day after gastric surgery developed an infection. On the other hand, the incidence of SIRS in patients who did not develop an infection was high on both the third and fourth days after esophageal surgery. It was nearly impossible to predict who would develop an infection in esophageal surgery. The high incidence of postoperative infections, and their significant consequences justify planned successive postoperative antibiotic use in esophageal surgery.