Actions of remimazolam on inhibitory transmission of rat spinal dorsal horn neurons

Remimazolam is an ultra-short benzodiazepine that acts on the benzodiazepine site of γ-aminobutyric acid (GABA) receptors in the brain and induces sedation. Although GABA receptors are found localized in the spinal dorsal horn, no previous studies have reported the analgesic effects or investigated the cellular mechanisms of remimazolam on the spinal dorsal horn. Behavioral measures, immunohistochemistry, and in vitro whole-cell patch-clamp recordings of dorsal horn neurons were used to assess synaptic transmission. Intrathecal injection of remimazolam induced behavioral analgesia in inflammatory pain-induced mechanical allodynia (six rats/dose; p < 0.05). Immunohistochemical staining revealed that remimazolam suppressed spinal phosphorylated extracellular signal-regulated kinase activation (five rats/group, p < 0.05). In vitro whole-cell patch-clamp analysis demonstrated that remimazolam increased the frequency of GABAergic miniature inhibitory post-synaptic currents, prolonged the decay time (six rats; p < 0.05), and enhanced GABA currents induced by exogenous GABA (seven rats; p < 0.01). However, remimazolam did not affect miniature excitatory post-synaptic currents or amplitude of monosynaptic excitatory post-synaptic currents evoked by Aδ- and C-fiber stimulation (seven rats; p > 0.05). This study suggests that remimazolam induces analgesia by enhancing GABAergic inhibitory transmission in the spinal dorsal horn, suggesting its potential utility as a spinal analgesic for inflammatory pain.

Delayed paraparesis after posterior spinal fusion for congenital scoliosis: a case report

INTRODUCTION

Although multimodal intraoperative neuromonitoring (IONM), which has high sensitivity and specificity, is typically performed during spinal deformity surgery, neurological status may deteriorate with delay after surgical maneuvers. Here, we report a rare case of delayed postoperative neurological deficit (DPND) that was not detected by IONM during posterior spinal fusion (PSF) for congenital scoliosis.

CASE PRESENTATION

A 14-year-old male presented with congenital scoliosis associated with T3 and T10 hemivertebrae. Preoperative Cobb angle of proximal thoracic (PT) and main thoracic (MT) curves were 50° and 41°, respectively. PSF (T1-L1) without hemivertebrectomy was performed, and the curves were corrected to 31° and 21° in the PT and MT curves, respectively, without any abnormal findings in IONM, blood pressure, or hemoglobin level. However, postoperative neurological examination revealed complete loss of motor function. A revision surgery, release of the curve correction by removing the rods, was immediately performed and muscle strength completely recovered on the first postoperative day. Five days postoperatively, PSF was achieved with less curve correction (36° in the PT curve and 26° in the MT curve), without postoperative neurological deficits.

DISCUSSION

Possible mechanisms of DPND in our patient are spinal cord ischemia due to spinal cord traction caused by scoliosis correction and spinal cord kinking by the pedicle at the concave side. Understanding the possible mechanisms of intra- and postoperative neural injury is essential for appropriate intervention in each situation. Additionally, IONM should be continued to at least skin closure to detect DPND observed in our patient.

Omega-conotoxin MVIIA reduces neuropathic pain after spinal cord injury by inhibiting N-type voltage-dependent calcium channels on spinal dorsal horn

Spinal cord injury (SCI) leads to the development of neuropathic pain. Although a multitude of pathological processes contribute to SCI-induced pain, excessive intracellular calcium accumulation and voltage-gated calcium-channel upregulation play critical roles in SCI-induced pain. However, the role of calcium-channel blockers in SCI-induced pain is unknown. Omega-conotoxin MVIIA (MVIIA) is a calcium-channel blocker that selectively inhibits N-type voltage-dependent calcium channels and demonstrates neuroprotective effects. Therefore, we investigated spinal analgesic actions and cellular mechanisms underlying the analgesic effects of MVIIA in SCI. We used SCI-induced pain model rats and conducted behavioral tests, immunohistochemical analyses, and electrophysiological experiments (in vitro whole-cell patch-clamp recording and in vivo extracellular recording). A behavior study suggested intrathecal MVIIA administration in the acute phase after SCI induced analgesia for mechanical allodynia. Immunohistochemical experiments and in vivo extracellular recordings suggested that MVIIA induces analgesia in SCI-induced pain by directly inhibiting neuronal activity in the superficial spinal dorsal horn. In vitro whole-cell patch-clamp recording showed that MVIIA inhibits presynaptic N-type voltage-dependent calcium channels expressed on primary afferent Aδ-and C-fiber terminals and suppresses the presynaptic glutamate release from substantia gelatinosa in the spinal dorsal horn. In conclusion, MVIIA administration in the acute phase after SCI may induce analgesia in SCI-induced pain by inhibiting N-type voltage-dependent calcium channels on Aδ-and C-fiber terminals in the spinal dorsal horn, resulting in decreased neuronal excitability enhanced by SCI-induced pain.

Surfactant-Free Decellularization of Porcine Aortic Tissue by Subcritical Dimethyl Ether

Porcine aortic tissue was decellularized by subcritical dimethyl ether (DME) used as an alternative to the surfactant sodium dodecyl sulfate. The process included three steps. For the first step, lipids were extracted from the porcine aorta using subcritical DME at 23 °C with a DME pressure of 0.56 MPa. Next, DME was evaporated from the aorta under atmospheric pressure and temperature. The second step involved DNA fragmentation by DNase, which was primarily identical to the common method. For the third step, similar to the common method, DNA fragments were removed by washing with water and ethanol. After 3 days of DNase treatment, the amount of DNA remaining in the porcine aorta was 40 ng/dry-mg, which was lower than the standard value of 50 ng/mg-dry. Hematoxylin and eosin staining showed that most cell nuclei were removed from the aorta. These results demonstrate that subcritical DME eliminates the need to utilize surfactants.

Ethanol-free antisolvent crystallization of glycine by liquefied dimethyl ether

Liquefied dimethyl ether (DME) was employed as an antisolvent to crystallize glycine from its aqueous solution. The proposed method can be performed at 20–25 °C and has the potential to reduce the energy consumption of drying or crystallizing using ethanol. α-Glycine crystals were successfully obtained from glycine aqueous solutions by mixing in liquefied DME, which was easily removed from the crystals by decompression. Contact with a liquefied DME/water mixture and small γ-glycine crystals resulted in the α-glycine converting to γ-glycine. This was only observed for saturated glycine solutions. We speculated that this conversion occurs via a solution-mediated transition. Pure liquefied DME is not capable of promoting solvent-mediated transitions, so saturated glycine solutions treated with the pure antisolvent can give α-glycine as the sole product.

Lipid emulsion injection-induced reversal of cardiac toxicity and acceleration of emergence from general anesthesia after scalp infiltration of a local anesthetic: a case report

Background

A scalp block or wound infiltration of local anesthetic is thought to effectively control post-craniotomy pain. However, it can result in local anesthetic toxicity (LAST), which is difficult to distinguish from brain damage due to the surgical procedure when emergence from general anesthesia is delayed. Lipid rescue (infusion of a lipid emulsion) is a widely accepted treatment for LAST.

Case presentation

A 64-year-old man underwent surgical resection of a glioma in the brainstem. While still under general anesthesia, and before suturing of the wound, he received a 20-mL scalp infusion of ropivacaine 0.75%. His emergence from anesthesia was delayed, his respiration was suppressed, and premature ventricular contractions occurred; all of which are symptoms of LAST. Injection of a 20% lipid emulsion rapidly alleviated these symptoms. Interestingly, the blood concentration of ropivacaine increased after lipid rescue.

Conclusions

The increase in ropivacaine concentration in the blood after lipid rescue suggests that the intravenously administered lipid emulsion absorbed the ropivacaine from the intoxicated brain and heart tissue. This finding is consistent with the lipid sink theory as a mechanistic explanation of lipid rescue.

Generating Approximate Solutions to the TTP using a Linear Distance Relaxation

In some domestic professional sports leagues, the home stadiums are located in cities connected by a common train line running in one direction. For these instances, we can incorporate this geographical information to determine optimal or nearly-optimal solutions to the n-team Traveling Tournament Problem (TTP), an NP-hard sports scheduling problem whose solution is a double round-robin tournament schedule that minimizes the sum total of distances traveled by all n teams. We introduce the Linear Distance Traveling Tournament Problem (LD-TTP), and solve it for n=4 and n=6, generating the complete set of possible solutions through elementary combinatorial techniques. For larger n, we propose a novel "expander construction" that generates an approximate solution to the LD-TTP. For n congruent to 4 modulo 6, we show that our expander construction produces a feasible double round-robin tournament schedule whose total distance is guaranteed to be no worse than 4/3 times the optimal solution, regardless of where the n teams are located. This 4/3-approximation for the LD-TTP is stronger than the currently best-known ratio of 5/3 + epsilon for the general TTP. We conclude the paper by applying this linear distance relaxation to general (non-linear) n-team TTP instances, where we develop fast approximate solutions by simply "assuming" the n teams lie on a straight line and solving the modified problem. We show that this technique surprisingly generates the distance-optimal tournament on all benchmark sets on 6 teams, as well as close-to-optimal schedules for larger n, even when the teams are located around a circle or positioned in three-dimensional space.

Region-specific expression and hormonal regulation of the first exon variants of rat prolactin receptor mRNA in rat brain and anterior pituitary gland

Recent studies have revealed the occurrence of five first exon variants of the rat prolactin receptor mRNA, suggesting that multiple promoters direct prolactin receptor transcription in response to different regulatory factors. In the present study, regional expression of these first exon variants, as well as two prolactin receptor subtypes generated by alternative splicing, was examined in the brains and anterior pituitary glands of female rats. Expression of the long-form was detected in the choroid plexus, hypothalamus, hippocampus, cerebral cortex and anterior pituitary gland, whereas the short form was detected only in the choroid plexus. E1-3 mRNA, a first exon variant, was detected in the choroid plexus, hypothalamus, and anterior pituitary gland, whereas E1-4 was detected only in the choroid plexus. Other variants were not detectable by the polymerase chain reaction protocol employed in this study. Ovariectomy increased the short form in the choroid plexus and the E1-3 expression in the choroid plexus and pituitary gland, but changes in the long-form and E1-4 expression were minimal. Replacement of oestrogens and prolactin suggest that oestrogens down-regulate E1-3 expression in the choroid plexus and pituitary gland, and that the negative effect of oestrogen is mediated by prolactin in the pituitary gland. The present results revealed the region-specific promoter usage in prolactin receptor mRNA transcription, as well as the involvement of oestrogens in the regulation of E1-3 mRNA expression in the brain and pituitary gland.

Abdominal aortic aneurysm with left-sided inferior vena cava. Report of a case

The combination of abdominal aortic aneurysms and congenital anomalies of the inferior vena cava and its tributaries, such as double inferior vena cava, left-sided inferior vena cava, circumaortic renal collar, and retroaortic renal vein, are very rare but of clinical importance to vascular surgeons since these conditions can increase the difficulty of aneurysm resection as well as the risk of venous injury and subsequent excessive bleeding. This report describes a case of an abdominal aortic aneurysm with a left-sided inferior vena cava, and reviews of the incidence, diagnosis, and treatment of these conditions.

Possible participation of outer mitochondrial membrane cytonchrome B5 in steroidogenesis in zona glomerulosa of rat adrenal cortex

Outer mitochondrial membrane cytochrome b5 (OMb) originally found in rat liver is an isoform of cytochrome b5 (b5) of the endoplasmic reticulum. In contrast to accumulated data on the physiological roles of b5, functions of OMb have not been well characterized except for its involvement in regeneration of ascorbic acid [i.e., in a semidehydroascorbate reductase (SDAR) system]. By using highly specific antibodies against rat OMb, we found immunohistochemically that OMb in the rat adrenal gland was most abundant in the zona glomerulosa (zG) among the three cortical zones, and the expression level was enhanced on angiotensin II-stimulation. SDAR activity was found in zG and inhibited by anti-OMb antibody. Moreover, the increase in plasma aldosterone concentration under Na+ -deficiency was suppressed by limited ascorbic acid (Asc) availability in rat mutants unable to synthesize Asc, while plasma corticosterone concentration was not affected. These data suggest that OMb, present abundantly in zG, participates in aldosterone formation in zG of rat under angiotensin II-stimulation through regeneration of Asc.

[Recurrent right atrial myxoma five years after removal of left atrial myxoma; report of a case]

A 41-year-old man had undergone resection of a left atrial myxoma 5 years previously. Echocardiography revealed a new mass in the right atrium. Because of had increased in size gradually, removal of the right atrial mass involving full-thickness resection of the fossa ovalis was performed. Cardiac myxoma has the potential for heterotopic recurrence.

Measles virus infection in the placenta of monozygotic twins

We report a case of monozygotic twins whose mother was infected with measles at 19 weeks' gestation. One of the twins died in utero at 32 weeks' gestation. The placenta of the stillbirth showed massive fibrin deposition, and some residual trophoblasts contained many inclusion bodies positive for measles virus antigen. Fetal organs and cells other than a few splenic lymphocytes showed no evidence of measles virus infection. The placenta of the surviving infant showed focal intervillous fibrin deposits, and only a few syncytiotrophoblasts were positive for measles virus antigen. At present, 7 months after the delivery, the surviving infant has not developed any sign of measles virus infection. Postpartum course of the mother has been uneventful, although high titers of serum anti-measles virus IgM persisted for 6 months after delivery. This case is informative in the following respects: the villous trophoblasts had diagnostic inclusion bodies and ultrastructural evidence of measles virus infection, the degree of viral involvement within the monochorionic placenta was uneven, both of the twins were virtually free from measles virus infection despite the marked involvement of the placenta, and measles virus infection had persisted in the monochorionic placenta for approximately 13 weeks.

A prospective clinical study on inhaled nitric oxide therapy for neonates in Japan

BACKGROUND

This is the first report about a prospective clinical investigation to study the efficacy and safety of nitric oxide (NO) inhalation in infants with persistent pulmonary hypertension of the newborn (PPHN) in Japan.

METHODS

Patients in the present study had to meet the following entry criteria: (i) they had to be younger than 7 days of age; (ii) they had to have evidence of PPHN as defined by echocardiograph; (iii) they had to have severe systemic hypoxemia under mechanical ventilation at 100% oxygen supplementation; and (iv) they had to have a failure to respond to conventional therapies. Patients were excluded from this trial if they had any of the following: hypoplastic lung, structural cardiac lesions or severe multiple anomalies.

RESULTS

Nitric oxide inhalation therapy was performed in 68 infants who had severe PPHN at 18 hospitals between May 1995 and May 1997. At birth, 21 of 68 infants (31%) weighed less than 1,500 g and 39 infants weighed more than 2,500 g. The diagnoses associated with PPHN were as follows: 27 infants had meconium aspiration syndrome, 15 infants had dry lung syndrome, nine infants had congenital diaphragmatic hernia, six infants had respiratory distress syndrome, three infants had pneumonia and eight infants had other diagnoses. The mean oxygenation index (OI) before NO inhalation therapy in 68 infants was 43.2; 55 infants (81%) had good responses.

CONCLUSIONS

These results may be valuable for further randomized controlled and double-blind trials in Japan to evaluate whether NO inhalation therapy is more effective than conventional therapy in infants with severe PPHN.

Blockade of the extracellular signal-regulated kinase pathway induces marked G1 cell cycle arrest and apoptosis in tumor cells in which the pathway is constitutively activated: up-regulation of p27(Kip1)

Constitutive activation of the ERK pathway is associated with the neoplastic phenotype of a relatively large number of human tumor cells. Blockade of the ERK pathway by treatment with PD98059, a specific inhibitor of mitogen-activated protein (MAP) kinase/ERK kinase (MEK), completely suppressed the growth of tumor cells in which the pathway is constitutively activated (RPMI-SE and HT1080 cells). Consistent with its prominent antiproliferative effect, PD98059 induced a remarkable G(1) cell cycle arrest, followed by a modest apoptotic response, in these tumor cells. Selective up-regulation of p27(Kip1) was observed after PD98059 treatment of RPMI-SE and HT1080 cells. Overexpression in RPMI-SE cells of either a kinase-negative form of MEK1 or wild-type MAP kinase phosphatase-3 also induced up-regulation of p27(Kip1). The up-regulation of p27(Kip1) correlated with increased association of p27(Kip1) with cyclin E-cyclin-dependent kinase (CDK) 2 complexes, a concomitant inhibition of cyclin E-CDK2 kinase activity, and a consequent decrease in the phosphorylation state of retinoblastoma protein, which would culminate in the marked G(1) cell cycle arrest observed in these tumor cells. These results suggest that the complete growth suppression that follows specific blockade of the ERK pathway in tumor cells in which the pathway is constitutively activated is mediated by up-regulation of p27(Kip1).

Terminal warm blood cardioplegia improves the recovery of myocardial electrical activity. A retrospective and comparative study

OBJECTIVE

The effect of terminal warm blood cardioplegia was analyzed in 191 patients undergoing either coronary artery bypass grafting (CABG) or prosthetic heart valve replacement between Jan. 1990 and Dec. 1995.

METHODS

Patients were subdivided into 3 historical cohorts based on the method of myocardial protection: Group A (n = 106), multidose cold crystalloid glucose-potassium cardioplegia, alone; Group B (n = 37), cold crystalloid glucose-potassium cardioplegia plus terminal warm blood cardioplegia, Group C (n = 48), cardioplegia induction with cold crystalloid glucose-potassium cardioplegia, maintenance with multidose cold blood cardioplegia, and terminal warm blood cardioplegia.

RESULTS

Of patients undergoing CABG, 5.6% of group A, 70.4% of group B, and 86.7% of group C spontaneously resumed sinus rhythm after aortic declamping, as did 9.1% of group A, 60.0% of group B, and 55.6% of group C of patients undergoing prosthetic heart valve replacement. The incidence of spontaneous recovery was significantly better in groups B and C than in group A (p < 0.05). Over 90% of patients without terminal warm blood cardioplegia developed ventricular fibrillation or tachycardia requiring electrical cardioversion (p < 0.05). Postoperatively, patients without terminal warm blood cardioplegia required temporary epicardial pacing more frequently than those with terminal warm blood cardioplegia (p < 0.05). In patients undergoing prosthetic heart valve replacement, groups B and C, the incidence of postoperative atrial fibrillation was significantly lower than in group A.

CONCLUSION

Terminal warm blood cardioplegia thus promoted better postoperative electrophysiological cardiac recovery.

Specific activation of the p38 mitogen-activated protein kinase signaling pathway and induction of neurite outgrowth in PC12 cells by bone morphogenetic protein-2

Bone morphogenetic protein (BMP)-2 has the capacity to induce the neuronal differentiation of PC12 cells. Unlike nerve growth factor, however, BMP-2 failed to induce the activation of the 41-/43-kDa mitogen-activated protein (MAP) kinase pathway in these cells. In contrast, BMP-2 characteristically induced the sustained activation of the p38 MAP kinase pathway. Pretreatment of PC12 cells with SB203580 inhibited the BMP-2-induced neurite outgrowth formation in a dose-dependent manner; this inhibition coincided well with the ability of SB203580 to inihibit the BMP-2-induced activation of the p38 MAP kinase pathway. Overexpression in PC12 cells of wild-type MAP kinase kinase (MKK)-6 enhanced the BMP-2-induced activation of p38 MAP kinase, whose activation correlated well with the ability of these cells to induce neurite outgrowth in response to BMP-2. Transient expression of kinase-negative forms of MKK3/6 inhibited the formation of neurite outgrowth in response to BMP-2. Furthermore, expression of constitutively active forms of MKK3/6 induced neurite outgrowth without BMP-2 stimulation, and SB203580 inhibited this induction. These results clearly indicate that activation of the p38 MAP kinase pathway is necessary for BMP-2-induced neuronal differentiation of PC12 cells. Our results also suggest that activation of the p38 MAP kinase pathway alone can induce the neuronal differentiation of PC12 cells.

Constitutive activation of the 41-/43-kDa mitogen-activated protein kinase signaling pathway in human tumors

The 41-kDa and 43-kDa mitogen-activated protein (MAP) kinases play a pivotal role in the mitogenic signal transduction pathway and are essential components of the MAP kinase cascade, which includes MAP kinase kinase (MEK) and Raf-1. As aberrant activation of signal transducing molecules such as Ras and Raf-1 has been linked with cancer, we examined whether constitutive activation of the 41-/43-kDa MAP kinases is associated with the neoplastic phenotype of 138 tumor cell lines and 102 primary tumors derived from various human organs. Constitutive activation of the MAP kinases was observed in 50 tumor cell lines (36.2%) in a rather tissue-specific manner: cell lines derived from pancreas, colon, lung, ovary and kidney showed especially high frequencies with a high degree of MAP kinase activation, while those derived from brain, esophagus, stomach, liver and of hematopoietic origin showed low frequencies with a limited degree of MAP kinase activation. We also detected constitutive activation of the 41-/43-kDa MAP kinases in a relatively large number of primary human tumors derived from kidney, colon and lung tissues but not from liver tissue. Many tumor cells, in which point mutations of ras genes were detected, showed constitutive activation of MAP kinases, however, there were also many exceptions to this observation. In contrast, the activation of the 41-/43-kDa MAP kinases was accompanied by the activation of Raf-1 in the majority of tumor cells and was completely associated with the activation of MEK and p90rsk in all the tumor cells examined. These results suggest that the constitutive activation of 41-/43-kDa MAP kinases in tumor cells is not due to the disorder of MAP kinases themselves, but is due to the disorder of Raf-1, Ras, or some other signaling molecules upstream of Ras.

[Mitral valve replacement for three cases of hypertrophic obstructive cardiomyopathy--surgical treatment]

Three patients with obstructive cardiomyopathy underwent surgical treatment. Mitral valve replacement was performed in all three cases and myectomy of hypertrophic septal muscle was performed in one case. The pressure gradients between the left ventricle and the aorta was less than 10 mmHg in all cases after surgery, Clinical symptoms strikingly improved in three cases. An accurate surgical treatment could be achieved by choosing either myotomy-myectomy, mitral valve replacement or both in the setting of individual condition of each patients.

Activation of the 41/43 kDa mitogen-activated protein kinase signaling pathway is required for hepatocyte growth factor-induced cell scattering

Hepatocyte growth factor (HGF) markedly induced the spreading, dissociation and scattering of Madin-Darby canine kidney epithelial cells (MDCK) and human stomach adenocarcinoma cells (TMK1). Scattering of MDCK and TMK1 cells was induced by 12-O-tetradecanoyl-phorbol-13-acetate (PMA) and epidermal growth factor (EGF), respectively. In all these agent-stimulated cells, rapid activation of Raf-1, MAP kinase/ERK kinase (MEK), 41/43 kDa MAP kinases and p90rsk was commonly observed. In contrast, PMA neither induced the scattering nor activation of all these kinases in TMK1 cells. Pretreatment of MDCK and TMK1 cells with 2-(2-amino-3-methoxyphenyl) choromone (AMPC), a specific inhibitor of MEK, selectively inhibited the HGF-, PMA- and EGF-stimulated activities of MEK, 41/43 kDa MAP kinases and p90rsk in a dose dependent manner. AMPC-pretreatment, however, did not affect HGF-, PMA- or EGF-induced activation of Raf-1, nor HGF-induced activation of phosphatidylinositol 3-kinase in these cells. Importantly, HGF-, PMA- and EGF-induced scattering of MDCK and TMK1 cells was inhibited at doses of AMPC similar to those that gave comparable levels of inhibition of the activities of MEK, 41/43 kDa MAP kinases and p90rsk. These results suggest that activation of the 41/43 kDa MAP kinase signaling pathway is required for the motility response of MDCK and TMK1 cells induced by agents such as HGF, PMA and EGF.

[High-dose methylprednisolone-containing chemotherapy in advanced invasive thymoma--report of three cases]

During the period from May, 1995 to August, 1996, three patients with Stage III or IVa invasive thymoma received chemotherapy consisting of cisplatin, doxorubicin and methylprednisolone (1000 mg on days 1 through 5, and 500 mg on days 6 and 7). The first case, a 55-year-old woman, who underwent extended thymectomy 7 years ago, was found to have a recurrent tumor in the left pleural cavity. The second case, a 38-year-old man, who had first operation 3 years ago, developed recurrent tumor in the right pleural cavity. These two patients were treated with the above regimen as the primary mode of therapy. The third case, a 61-year-old woman, had a thymoma with direct invasion to right upper lobe. The same chemotherapy regimen was employed as the induction chemotherapy. All patients showed a major response to treatment with only a small amount of tumor remaining. The effectiveness of chemotherapy in the treatment of malignant tumors has been recently reported to be at least partly due to induction of apoptosis. Steroids are known to induce apoptosis in normal thymic cells, and thus steroid in chemotherapy regimen against invasive thymoma may enhance the effect of anti-cancer drugs through the induction of apoptosis.

Constitutive activation of mitogen-activated protein (MAP) kinases in human renal cell carcinoma

Mitogen-activated protein kinases (MAPKs) play a pivotal role in the mitogenic signal transduction pathway and are essential components of the MAPK cascade, which includes MEK (also known as MAP kinase kinase), Raf-1, and Ras. In this study, we examined whether constitutive activation of the MAPK cascade was associated with the carcinogenesis of human renal cell carcinomas in a series of 25 tumors and in corresponding normal kidneys. Constitutive activation of MAPKs in tumor tissue, as determined by the appearance of phosphorylated forms, was found in 12 cases (48%), and this activation was confirmed by a direct in vitro kinase assay of immunoprecipitate using myelin basic protein as the substrate. The phosphorylation of MEK and of Raf-1, as monitored by a mobility shift in SDS-PAGE, which is reportedly associated with the activation of these kinases, occurred in 9 of 18 cases (50%) and in 6 of 11 cases (55%) respectively. The activation of MAPKs was correlated with MEK activation (P = 0.0045) and with Raf-1 activation (P = 0.067). Furthermore, overexpression of MEK was found in 13 of 25 cases (52%) by Western blot analysis, and this overexpression was associated significantly with MAPK activation (P = 0.034). No mutations were noted in H-,K-, or N-ras genes by PCR direct sequencing in any of the 25 tumor samples. Of the patients studied, 8 of 18 (44%) stage pT2 patients and four of six (67%) stage pT3 patients showed MAPK activation. The single stage pT1 patient did not evidence MAPK activation. Furthermore, one of seven (14%) grade 1 patients, 9 of 13 (69%) grade 2 patients, and two of five (40%) grade 3 patients showed MAPK activation (grade 1 versus grades 2 and 3, P = 0.046). Our results suggest that constitutive activation of MAPKs may be associated with the carcinogenesis of human RCCs.

[A case of left atrial myxoma with remarkable elevation of serum alkaline phosphatase level]

A 53-year-old woman was admitted suffering from high grade fever. Laboratory findings revealed leukocytosis, high CRP, high erythrocyte sedimentation rate and remarkable elevation of serum alkaline phosphatase level. Echocardiogram demonstrated left atrial tumor which was later diagnosed as myxoma. Although remarkable elevation of serum alkaline phosphatase level often indicates malignant disease, tumor makers were normal level and whole body computerized tomography couldn't detect other noncardiac diseases. Because of patient's deterioration due to sustained high grade fever, the left atrial tumor was excised. After the excision of the left atrial myxoma, patient's clinical signs and symptoms disappeared, and the serum alkaline phosphatase level was gradually normalized. We conclude that the cause of remarkable elevation of serum alkaline phosphatase level was the left atrial myxoma.

[Three cases of adult intrapulmonary sequestration]

Three cases of adult intrapulmonary sequestration were presented. They were all females ranging from 22 to 49-year-old (mean age 35 yrs.). Chest X-rays showed abnormal shadows in the right or left lower lobe. Aortograms showed aberrant arteries in each cases, and the diagnosis of pulmonaly sequestration was made preoperatively. Lobectomies were performed in all cases because of recurrent bronchopulmonary infections. We could not classify our cases based on Pryce's classification by unclear margins between sequestrated lungs and normal pulmonary tissues. All cases had no histories of infantile bronchopulmonary infections which supported the theory of acquired origin.

[A case of penetrating chest injury with tension hemothorax by gunshot]

The patient, a 36-year-old male, was admitted with massive hemoptysis. He had two gunshot wounds in the right lateral abdomen and supraclavicular fossa. His chest X-ray showed right tension hemothorax. Emergency thoracotomy and laparotomy were performed. Massive bleeding from the right pulmonary artery (A4+5), lacerations in the diaphragm and injuries of the liver were found. We performed right middle lobectomy, S3 segmentectomy and plication of the diaphragm and liver. He was discharged uneventfully.

[Pulmonary arteriovenous fistula with Rendu-Osler-Weber disease and its HLA typing--a review and report of 87 cases of fistula]

Seven cases with pulmonary arteriovenous fistula (PAVF) in our hospital were reviewed on clinical data and HLA antigens. Furthermore, 80 reported cases of PAVF in Japan were summarized about the association with Rendu-Osler-Weber disease (Osler disease). Thirty-six (41%) of the total 87 cases had Osler disease. Fistulas were single in 46 cases and multiple in 41; unilateral in 56 and bilateral in 31. Operations were performed in 61 cases, embolizations in 8 and no therapy in 18. The frequency of the bilateral fistulas and multiple ones was significantly higher in cases with Osler disease (n = 36) than in those without Osler disease (n = 51) (p < 0.025). In our 7 cases, 6 had Osler disease. Aggregation of platelets was decreased in one case. Contralateral fistulas were recurred in another case 8 years after surgery. Three cases with Osler disease had the HLA halotype A26Bw6Bw61 which did not coincide with that in previous reports. We concluded that various HLA halotypes might exist in Osler disease.

[A case of malignant fibrous histiocytoma of the pulmonary artery]

We presented a rare case of primary pulmonary artery sarcoma. A 27-year-old female was admitted with fever and back pain. Her chest X-ray showed right pleural effusion and infiltrate in the right lower lobe. Enhanced chest CT scan and pulmonary angiogram showed an intraluminal filling defect of the pulmonary trunk. She was operated on under cardiopulmonary bypass. Following the incision of the pulmonary trunk, a polypoid soft yellowing mass was exposed. The local tumor resection and the right pneumonectomy were performed. Histological and immunohistochemical studies of the tumor revealed malignant fibrous histiocytoma. She made a good recovery but died of distant metastases 10 months after surgery.

[Cardiac surgery in hemodialysis patients]

Five hemodialysis patients have undergone cardiac procedures between March 1986 and August 1992. These cases include two coronary artery bypass operations and three valve replacements. The average time on dialysis prior to surgery was 67 months and all patients were in NYHA grade 3 or 4. All patients were dialyzed two or three consecutive days before surgery. Intraoperative extracorporeal ultrafiltration method (ECUM) was used in all patients. In one patients hemodialysis was also performed intraoperatively in addition to ECUM. All patients received platelet transfusions after cardiopulmonary bypass because of known platelet dysfunction and coagulation problems in renal failure patients. Our first patient, who had been dialyzed on operative day using regional heparinization, returned operating room for bleeding on the first postoperative day, then in another four patients hemodialysis was begun on the first or second postoperative day using nafamostat mesilate as anticoagulant. No perioperative deaths occurred and all patients remain alive with a mean follow-up of 28 months. In summary, cardiac surgery can be successfully carried out on five chronic hemodialysis patients, hemodialysis can be performed safely on early postoperative day, and nafamostat mesilate is a useful anticoagulation agent to prevent postoperative bleeding complications.

Tc-99m-methylene diphosphonate (Tc-99 MDP) and Ga-67 concentration in soft tissue malignant fibrous histiocytoma (MFH): case report

A case of calcifying soft tissue malignant fibrous histiocytoma (MFH) which showed a concentration of Tc-99m MDP and Ga-67 citrate, is presented. Tc-99m MDP and Ga-67 citrate scintigraphies of the thigh mass were correlated with conventional radiography, computed tomography (CT) and angiography.

[Effects of NIK-228 on gastric acid secretion in rats using the congo red sprayed method]

We have reported the antiulcer activities of a new compound that we named NIK-228 (3-hydroxy-methyl-2-methylimidazo [2, 1-b] benzothiazole). In the present report, we studied the antisecretory effects of NIK-228 on basal and stimulated gastric acid secretion using the Congo red sprayed method. Male Wistar rats (200 to 250 g) were used after 24 hr of fasting (without water). NIK-228, atropine and cimetidine were administered orally or intravenously 1 hr before operation for Congo red spraying. NIK-228 (100 mg/kg, p.o.), atropine (5 mg/kg p.o.) and cimetidine (100 mg/kg, p.o.) all inhibited basal gastric acid secretion. Oral administration of NIK-228 and atropine inhibited gastrin, 2-deoxy-D-glucose (2-DG) and bethanechol-induced acid secretion, but didn't inhibit histamine-induced acid secretion. Cimetidine inhibited all of histamine, gastrin, 2-DG and bethanechol-induced acid secretion. In vagotomized rats, oral and intravenous administration of atropine both inhibited bethanechol-induced acid secretion, but NIK-228 was not inhibited. These results suggested that antisecretory effects of NIK-228 were caused by the central vagal systems.

[Effects of 3-hydroxymethyl-2-methylimidazo [2, 1-b] benzothiazole (NIK-228) on gastric acid secretion and various experimental peptic ulcers in rats]

We examined the antisecretory and antiulcer activities of NIK-228 in rats. Male Wistar rats (200 to 250 g) were used under 24 to 48 hr fasted (without water) conditions. NIK-228 and famotidine were administered orally 1 hr before pylorus ligation, stress or each ulceration inducer. Both NIK-228 (10 to 100 mg/kg) and famotidine (0.3 to 3 mg/kg) dose-dependently inhibited gastric secretion in pylorus ligated rats. Water-immersion stress-, indomethacin- or pylorus ligation (Shay)-induced gastric ulcers were dose-dependently inhibited by NIK-228 (10 to 100 mg/kg), but only water-immersion stress and indomethacin induced ulcers were dose-dependently inhibited by famotidine (0.03 to 3 mg/kg). Ethanol- and 0.6 N HCl-induced gastric lesions were remarkably inhibited by NIK-228 (ED50 = 2.7 and 5.6 mg/kg), but tended to be inhibited also by famotidine (0.3 to 3 mg/kg). Cysteamine-induced duodenal ulcer was inhibited significantly by NIK-228 (30, 100 mg/kg) or famotidine (3 mg/kg). NIK-228 may produce its antiulcer effects via antisecretory and cytoprotective effects. These results suggest that NIK-228 has antisecretory and antiulcer activities.

[Successful management of mycotic abdominal arteriovenous fistula complicated with infective endocarditis--a case report]

A 56-year-old man, who had been febrile for one month, suddenly had severe left foot pain. He also became dyspneic. Embolic occlusion of left femoral artery as well as severe acute aortic regurgitation due to Staphylococcus endocarditis was demonstrated by arteriography and echocardiography. The patient underwent emergency aortic valve replacement and above knee amputation of left foot at the same time. Postoperatively he continued to be hypotensive and, at 6th postoperative day, abdominal vascular bruit was first observed. Aortography revealed left common iliac aneurysm with an arterio-venous fistula. The aneurysm was excised and venous opening of the fistula was oversewn. Aortic end was reconstructed with bifurcated prosthetic graft. Antibiotic therapy was continued 6 weeks. His postoperative course was uneventful.

[Concomitant coronary artery bypass and cholecystectomy: a case report]

A case is reported in which simultaneous surgical correction of coronary atherosclerosis and cholelithiasis was performed. A 71-year-old man was admitted with severe stable angina and right hypochondrial dull pain. Coronary angiograms disclosed severe triple vessel disease, and abdominal echography demonstrated gallstone. He underwent bypass of left anterior descending, diagonal, obtuse marginal, and right coronary arteries with autogenous saphenous vein on cardiopulmonary bypass. The procedure was followed immediately by cholecystectomy. His postoperative course was uneventful.

[Right ventricular function in retrograde cardioplegia for myocardial protection--an experimental study]

Anterior cardiac veins which are the main drainage vessels of the right ventricle drain directly into the right atrium. Therefore, the right ventricular wall may not be perfused effectively during open heart surgery by the use of retrograde cardioplegic method resulting in postoperative right ventricular dysfunction. Seventeen mongrel dogs were subjected to this study and were placed on cardiopulmonary bypass using a conventional heart-lung machine. Total aortic cross-clamping time was 60 minutes in all dogs. In Group I (n = 6), 4 degrees C St. Thomas' Hospital solution (15 ml/kg body weight) was injected into the aortic root by the use of a syringe. Cardioplegic solution was replenished every 20 minutes with a half of the initial dose (7.5 ml/kg body weight). Group II (n = 6) were the dogs with the retrograde cardioplegia in which 4 degrees C St. Thomas' Hospital solution (15 ml/kg body weight) was given retrogradely from the coronary sinus by the drip method at the height of 60 cm, and the replenishing dose and interval of cardioplegia were the same as Group I. Group III (n = 5) was the dogs treated with retrograde cardioplegia identical to Group II and the combined use of topical cooling with ice-slush. The hearts were resuscitated after 60 minutes of aortic cross-clamping. Right ventricular functions such as cardiac output, right atrial pressure, right ventricular end-diastolic pressure, right ventricular max dp/dt, and shortening fraction of the right ventricle were measured 15, 30, 45, and 60 minutes after cardiac resuscitation respectively. In Group II, right atrial pressure was significantly elevated from the control value 15 and 30 minutes after cardiac resuscitation. On the other hand, all indices of right ventricular functions in Group III showed insignificant changes. The present experimental study demonstrated the retrograde cardioplegic method could produce right ventricular perfusion resulting in right ventricular dysfunction early after cardiac resuscitation. This deleterious effect however could be prevented by the combined use of topical cooling of the right ventricle with ice-slush.