Relationship between the administration of nicardipine hydrochloride and the development of delirium in patients on mechanical ventilation

A history of hypertension is a known risk factor for delirium in patients in intensive care units, but the effect of antihypertensive agents on delirium development is unclear. Nicardipine, a calcium channel blocker, is widely used in ICU as a treatment agent for hypertensive emergency. This study investigated the relationship between the administration of nicardipine hydrochloride and delirium development in patients under mechanical ventilation. We conducted a medical chart review of 103 patients, who were divided into two groups according to the use of nicardipine hydrochloride. The prevalence of delirium was compared with respect to factors such as age, sex, laboratory data, and medical history, by multivariate analysis. 21 patients (20.4 %) were treated with nicardipine hydrochloride in 103 patients. The treatment and non-treatment groups differed significantly in age (72 vs. 65 years) and history of high blood pressure (57% vs. 11%). Multivariate analysis revealed that patients in the treatment group developed delirium significantly less often than those in the non-treatment group (19% vs. 48%). These results suggested that treatment of high blood pressure with nicardipine hydrochloride is a possible method for preventing the development of delirium.

Teneligliptin for the treatment of type 2 diabetes

Teneligliptin, characterized by a "J-shaped" structure formed by five consecutive rings, is a novel dipeptidyl peptidase 4 (DPP IV) inhibitor for the treatment of type 2 diabetes. Teneligliptin is eliminated via excretion with a half-life of 24.2 hours in human plasma from the kidney and metabolism involving certain enzymes. Hence, dose adjustment is not required in patients with renal impairment. A pharmacokinetic/pharmacodynamic study revealed that teneligliptin inhibits DPP IV activity over 24 hours, with elevation of activated glucagon-like peptide 1 (GLP-1) levels and the resulting suppression of postprandial hyperglycemia at all three daily meals. Monotherapy for 12 weeks significantly decreased hemoglobin A1c (HbA1c), fasting blood glucose, and 2-hour postprandial blood glucose levels in patients with type 2 diabetes. The therapeutic efficacy of teneligliptin over 52 weeks was confirmed not only as monotherapy but also as add-on therapy in patients with inadequately controlled blood glucose levels with sulfonylureas or thiazolidinediones. The incidence of adverse drug reactions was approximately 10% in all clinical studies of patients with type 2 diabetes conducted in Japan. The incidence of hypoglycemia was comparable in patients receiving teneligliptin or placebo, and no serious hypoglycemia was observed. Thus, teneligliptin is a novel antihyperglycemic agent with a preferable profile in terms of long-term efficacy and safety in patients with type 2 diabetes.

Paracrine control of mesenteric perivascular axo-axonal interaction

Immunohistochemical study of rat mesenteric arteries showed dense innervation of adrenergic nerves, calcitonin gene-related peptide (CGRP)-containing nerves (CGRPergic nerves), nitric oxide-containing nerves (nitrergic nerves). Double-immunostaining revealed that most CGRPergic or nitrergic nerves were in close contact with adrenergic nerves. CGRPergic and transient receptor potential vanilloid-1 (TRPV1)-immunopositive nerves appeared in the same neurone. In rat perfused mesenteric vascular beds without endothelium and with active tone, perfusion of nicotine, or bolus injection of capsaicin and acetylcholine and periarterial nerve stimulation (PNS) lowered pH levels of out flowed perfusate concomitant with vasodilation. Cold-storage denervation of preparations abolished pH lowering induced by nicotine and PNS. Guanethidine inhibited PNS- and nicotine-, but not acetylcholine- and capsaicin-, induced pH lowering. Pharmacological analysis showed that protons were released not only from adrenergic nerves but also from CGRPergic nerves. A study using a fluorescent pH indicator demonstrated that nicotine, acetylcholine and capsaicin applied outside small mesenteric artery lowered perivascular pH levels, which were not observed in Ca(2+) free medium. Exogenously injected hydrochloric acid in denuded preparations induced pH lowering and vasodilation, which was inhibited by denervation, TRPV1 antagonists and capsaicin without affecting pH lowering. These results suggest that excitement of adrenergic nerves releases protons to activate TRPV1 in CGRPergic nerves and thereby induce vasodilation. It is also suggested that CGRPergic nerves release protons with exocytosis to facilitate neurotransmission via a positive feedback mechanism.

Overlapping free bone graft with galea-pericranium in reconstruction of the anterior skull base to prevent CSF leak and sequestrum formation

Background. Reconstruction of the skull base after resection of a tumour is important to prevent postoperative complications such as infectionsand cerebrospinal fluid (CSF) leakage. Several reconstructive methods of the anterior skull base have been reported but, their long-term results are not clear. Methods. We describe a technique used after removal of an olfactory neuroblastoma with infiltration of the skull base. The reconstructed dura was covered with a galeal patch, a replicated galeal-pericranial flap, a graft from the inner table of skull, and a vascularised galeal-pericranial flap placed on the skull base defect. All layers were fixed with fibrin glue. Conclusion. Three dimensional computed tomography (3D-CT) at bone window settings demonstrated the bone graft covered the bone defect and was not absorbed and after 11 years there have been no signs of tumour regrowth or complications.

Life-style activities in systemic lupus erythematosus

OBJECTIVE

We evaluated the life-style activities of outpatients with SLE and factors that reduce their social activities.

METHODS

SUBJECTS

SLE group = 60 patients, Control 1 = 30 healthy subjects and Control 2 = 30 patients with other autoimmune diseases. The Frenchay Activity Index (FAI), Zung's self-rating depression scale (SDS), and the Japanese version of the Philadelphia Geriatric Center morale scale-revised (MS) were compared between groups. Relation between FAI and age, disease duration, steroid dose, SDS, and MS were examined in the SLE group, Control 1, and Control 2.

RESULTS

Total scores by FAI was 28.1 +/-8.0 points in Control 1, whereas it was 26.5 +/- 5.8 points in Control 2 and 24.5 +/- 7.7 points in the SLE group. While there was no statistical difference between the SLE group and Control 2, the scores were significantly lower in the SLE group than in Control 1 (P < 0.05). In SLE patients, age, the duration of the disease, and the steroid dose had no correlation, but MS had a positive correlation (P < 0.05) and SDS had a negative correlation (P < 0.05). In Control 2, age, the duration of the disease, the steroid dose, MS and SDS had no correlation whereas there was significant negative relation between FAI and SDS in Control 1 (r= -0.516, P<0.005).

CONCLUSION

The significant relation between life-style activities and subjective well-being, and depression in SLE suggests that detection and treatment of mental status is important in improving the life-style activities of SLE patients.

Adrenomedullin facilitates reinnervation of phenol-injured perivascular nerves in the rat mesenteric resistance artery

Our previous report showed that innervation of calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-containing nerves in rat mesenteric resistance arteries was markedly reduced by topical application of phenol, and that nerve growth factor (NGF) facilitates the reinnervation of both nerves. We also demonstrated that a CGRP superfamily peptide, adrenomedullin, is distributed in perivascular nerves of rat mesenteric resistance arteries. In the present study, we investigated the influence of adrenomedullin on the reinnervation of mesenteric perivascular nerves following topical phenol treatment. Under pentobarbital-Na anesthesia, 8-week-old Wistar rats underwent in vivo topical application of phenol (10% phenol in 90% ethanol) to the superior mesenteric artery proximal to the bifurcation of the abdominal aorta. After the treatment, the animals were subjected to immunohistochemistry of the third branch of small arteries proximal to the intestine and to vascular responsiveness testing on day 7. Topical phenol treatment caused marked reduction of the density of NPY-like immunoreactive (LI)- and CGRP-LI nerve fibers in the arteries. Adrenomedullin (360 or 1000 ng/h) or NGF (250 ng/h), which was administered intraperitoneally for 7 days using an osmotic mini-pump immediately after topical phenol treatment, significantly increased the density of CGRP-LI- and NPY-LI nerve fibers compared with saline. Treatment with adrenomedullin (1000 ng/h) or NGF restored adrenergic nerve-mediated vasoconstriction and CGRP nerve-mediated vasodilation in the perfused mesenteric artery treated topically with phenol. These results suggest that adrenomedullin, like NGF, has a facilitatory effect on the reinnervation of perivascular nerves.

Innervation and functional changes in mesenteric perivascular calcitonin gene-related peptide- and neuropeptide Y-containing nerves following topical phenol treatment

We have previously shown that age-related reduction of innervation and function in mesenteric perivascular calcitonin gene-related peptide-containing vasodilator nerves takes place in spontaneously hypertensive rats. The present study was performed to investigate innervation and functional changes in perivascular calcitonin gene-related peptide- and adrenergic neuropeptide Y-containing nerves after topical treatment with phenol, which damages nerve fibers, around the rat superior mesenteric artery. Under pentobarbital-Na anesthesia, 8-week-old Wistar rats underwent in vivo topical application of phenol (10% phenol in 90% ethanol) or saline (sham rats) to the superior mesenteric artery proximal to the bifurcation of the abdominal aorta. After the treatment, the animals were subjected to immunohistochemistry of the 3rd branch of small arteries proximal to the intestine and to vascular responsiveness testing on day 3 through day 14. The innervation levels of calcitonin gene-related peptide-like immunoreactivity containing fibers and neuropeptide Y-like immunoreactivity containing fibers were markedly reduced on day 3 to day 14 and on day 5 to day 14 after the treatment, compared with those in sham-operated rats, respectively. In perfused mesenteric vascular beds isolated from phenol-treated rats, adrenergic nerve-mediated vasoconstriction and calcitonin gene-related peptide nerve-mediated vasodilation in response to periarterial nerve stimulation (2-12 Hz) were significantly decreased on day 3 and day 7. Neurogenic release of norepinephrine in phenol-treated rats on day 7 was significantly smaller that that in sham-operated rats. Nerve growth factor content in the mesenteric arteries of phenol-treated rats was significantly lower than that in sham-operated rats. Administration of nerve growth factor using osmotic mini-pumps for 7 days after the phenol treatment resulted in greater density of calcitonin gene-related peptide- and neuropeptide Y-like immunoreactivity fibers than in phenol-treated rats and restored decreased vascular responses to periarterial nerve stimulation. These results suggest that topical phenol-treatment of the mesenteric artery effectively induces functional denervation of perivascular nerves, which can be prevented or reversed by nerve growth factor treatment.

A case of systemic lupus erythematosus with giant hepatic cavernous hemangioma

A 39-year old woman with antiphospholipid antibody positive systemic lupus erythematosus (SLE) was admitted to our department because of high fever, liver dysfunction and high level of C-reactive protein. At hospitalization, there was no anemia or jaundice. A tumor was palpable in the epigastric region, and there was tenderness in this region, but no muscular defense. There were no findings which indicated disease activity of SLE. The result of abdominal ultrasonography showed that there was a giant tumor, which occupied the majority of the left lobule of the liver, and a nonuniform ultrasound image was observed inside the tumor. The result of dynamic computed tomography (CT) showed peripheral globular enhancement, and enhancement then extended to the tumor center with time. Consequently, the patient was diagnosed with multiple hepatic hemangiomas. After admission, anemia rapidly deteriorated, and platelet count tended to decline. Therefore, intratumor hemorrhage was suspected, and emergent angiography was performed. For hemostatic purposes, transcatheter arterial embolization (TAE) and extended left hepatic lobectomy were performed. In patients with autoimmune diseases such as SLE and antiphospholipid syndromes, when thrombocytopenia is observed, care should be paid to identifying its cause, considering thrombocytopenia may be induced by hemangioma, although these cases are extremely rare.

Discovery of a novel enzyme, isonitrile hydratase, involved in nitrogen-carbon triple bond cleavage

Isonitrile containing an N triple bond C triple bond was degraded by microorganism sp. N19-2, which was isolated from soil through a 2-month acclimatization culture in the presence of this compound. The isonitrile-degrading microorganism was identified as Pseudomonas putida. The microbial degradation was found to proceed through an enzymatic reaction, the isonitrile being hydrated to the corresponding N-substituted formamide. The enzyme, named isonitrile hydratase, was purified and characterized. The native enzyme had a molecular mass of about 59 kDa and consisted of two identical subunits. The enzyme stoichiometrically catalyzed the hydration of cyclohexyl isocyanide (an isonitrile) to N-cyclohexylformamide, but no formation of other compounds was detected. The apparent K(m) value for cyclohexyl isocyanide was 16.2 mm. Although the enzyme acted on various isonitriles, no nitriles or amides were accepted as substrates.

Retro-odontoid soft tissue mass associated with atlantoaxial subluxation in an elderly patient: a case report

BACKGROUND

We present the case of an elderly patient with a retro-odontoid soft tissue mass associated with atlanto-axial subluxation.

CASE DESCRIPTION

A 74-year-old man was admitted to our hospital with progressive motor weakness in his right arm and neck pain. Radiological examinations revealed atlantoaxial subluxation and diffuse degenerative changes. Cervical MRI revealed a syrinx at the C1 level and a retro-odontoid soft tissue mass that severely compressed the spinal cord. The mass was of low signal intensity on both T1- and T2-weighted images. Conservative therapy could not stop the progression of his symptoms, so posterior decompression via a laminectomy of C1 and occipitocervical fixation was performed. These procedures resulted in an improvement of his neurological condition and in reduction of the mass and the compression of the spinal cord.

CONCLUSION

The patient lacked any specific conditions that might have caused chronic atlantoaxial subluxation. The degenerative changes alone might have provoked chronic atlantoaxial subluxation and a subsequent retro-odontoid soft tissue mass. In patients with this condition, posterior fixation without direct removal of the mass should be the first choice for surgical intervention.

Centrifuge polarizing microscope. II. Sample biological applications

The rationale, design and general performance of the CPM (centrifuge polarizing microscope) were described in Part I of this study (Inoué et al. J. Microsc. 201 (2001) 341-356. In this second part, we describe observations on several biological samples that we have explored over the past two years using the CPM. As described in the first part of the study, although the CPM was basically designed as a high-extinction centrifuge polarizing microscope, it also allows observations of the specimen exposed to high centrifugal fields up to 10 500 x g (earth's gravitational acceleration) in fluorescence (532-nm excitation) and in DIC (differential interference or Nomarski contrast).

Centrifuge polarizing microscope. I. Rationale, design and instrument performance

We first describe early uses of the centrifuge for deciphering physical properties and molecular organization within living cells, as well as the development and use of centrifuge microscopes for such studies. The rationale for developing a centrifuge microscope that allows high-extinction polarized light microscopy to observe dynamic fine structures in living cells is next discussed. We then describe a centrifuge polarizing microscope (CPM) that we developed for observing fine structural changes in living cells which are being exposed to up to approximately 11 500 times earth's gravitational field (g). With the specimen housed in a rotor supported on an air spindle motor, and imaged through an external microscope illuminated by a precisely synchronized flash of less than 10 ns duration from a Nd:YAG laser, the image of the spinning object remains steady up to the maximum speed of 11 700 rev min-1, or up to approximately 11 500 x g. The image is captured, at up to 25 frames s-1, by an interference-fringe-free CCD camera that is synchronized to the centrifuge rotor. At all speeds (in 100 rev min-1 increments), the image is resolved to better than 1 microm, while birefringence of the specimen, housed in a specially designed specimen chamber that suffers low-stress birefringence and prevents leakage of the physiological solutions, is detected with a retardance sensitivity of better than 1 nm. Differential interference contrast and fluorescence images (532 nm excitation) of the spinning specimen can also be generated with the CPM. The second part of this study (Inoué et al., J. Microsc. 201 (2001) 357-367, describes several biological applications of the CPM that we have explored. Individual live cells, such as oocytes and blood cells, are supported on a sucrose or Percoll density gradient while other cells, such as cultured fibroblasts and Dictyostelium amoebae, are observed crawling on glass surfaces. Observations of these cells exposed to the high G fields (centripetal acceleration/g) in the CPM are yielding many new results that lead to intriguing questions regarding the organization and function of fine structures in living cells and related quasi-fluid systems.

Eradication of Helicobacter pylori has no effect on gastric acidity in duodenal ulcer patients--evaluation of 24-h pH monitoring

It is accepted that eradication of Helicobacter pylori leads to healing of chronic active gastritis facilitates ulcer healing and prevents ulcer recurrence in duodenal ulcer (DU) patients. However, it is not entirely known whether the eradication of the bacteria normalizes gastric acid secretion and abolishes dyspeptic symptoms after ulcer healing. This study was aimed to evaluate the intragastric acidity and dyspeptic complaints before, and 3 months after, eradication in 18 endoscopically proven H. pylori positive DU patients. Gastric pH was measured by 24-h continuous intraluminal recording, serum gastrin measurements and Congo-red tests were also performed. Dyspeptic complaints and antacid consumptions were recorded in diary cards, antisecretory therapy was not allowed after the cessation of eradication therapy. Endoscopy, H. pylori status and Congo-red tests were controlled at the 6th and 12th week, while pH measurements and serum gastrin tests were performed at inclusion and 3 months later. Three patients dropped out and in 14 out of the remaining subjects healing of DUs and successful eradication was achieved by the 6th and 12th week controls. The 24-h median pH and the percentage of 24-h pH readings under pH 3 were not changing significantly by the 3-month controls (from 1.9+/-0.5 to 1.8+/-0.4 and from 52.6+/-5.5% to 58.6+/-5%, respectively). Similarly, no significant changes were observed in serum gastrin levels and dyspeptic symptom scores (from 72+/-7 pg/ml to 56.7+/-8 pg/ml and from 2.69+/-0.4 to 1.26+/-0.3, respectively). The antacid consumption was almost stable when compared with the pre- and post-eradication periods. It was concluded that despite successful H. pylori eradication and healing of DU, intragastric acidity does not change significantly at least 3 months after the therapy. The persisting dyspeptic symptoms and the need for antacid consumption suggest that some healed ulcer patients require antisecretory therapy in the post-eradication period.

A case of hypothalamic hamartoma associated with arachnoid cyst

A 14-year-old girl presented with seizures. Radiological examinations revealed an arachnoid cyst in left middle fossa and a cystic mass in the interpeduncular cistern. The cyst was opened and the wall of the cyst and a mass were biopsied. The histological findings were characteristic of an arachnoid cyst and hamartoma, respectively. A hypothalamic hamartoma associated with an arachnoid cyst is comparatively rare; however, such a case may help clarify the genesis of this malformation.

Hydrazide synthesis: novel substrate specificity of amidase

The amidase from Rhodococcus rhodochrous J1, which hydrolyses amide to acid and ammonia, was found to catalyze the synthesis of hydrazide using hydrazine as a substrate. This is the first report on the hydrazide synthesis through enzymatic reactions. The enzyme also acted on benzoic acid in the presence of hydrazine, yielding benzoic hydrazide. Together with the finding that benzoic hydrazide was converted into benzoic acid (when it was used as a substrate in the absence of hydrazine), these unique characteristics suggest that the reaction route for the formation of the acid from the hydrazide and that of the hydrazide from the acid are reversible to each other via the acyl-enzyme. Not only aromatic hydrazides but also aliphatic hydrazides were synthesized from the corresponding amides and hydrazine.

Nitrilase catalyzes amide hydrolysis as well as nitrile hydrolysis

While amides were reported to be completely inert as substrates for all nitrilases reported to date, the nitrilase from Rhodococcus rhodochrous J1, which catalyzes the hydrolytic cleavage of the C-N triple bond in nitrile to form acid and ammonium, was surprisingly found to catalyze hydrolysis of amide to acid and ammonium stoichiometrically. This nitrilase exhibited a Km of 2.94 mM for benzamide, similar to that for benzonitrile as the original substrate (2.10 mM), but the Vmax for benzamide was six orders of magnitude lower than that for benzonitrile. Benzamide inhibited the nitrilase reaction in a reversible, apparently competitive manner. A mutant nitrilase containing alanine or serine instead of Cys165, which is essential for nitrilase catalytic activity, showed no amidase activity. This observation demonstrated that Cys165 plays a crucial role in the hydrolysis of amides as well as nitriles. Together with some reports that certain nitrilases were previously noted to produce low amounts of amide as a by-product from nitrile, the above unexpected findings suggested the existence of a common tetrahedral intermediate in the nitrilase reaction involving nitrile or amide as a substrate.

The catalytic mechanism of amidase also involves nitrile hydrolysis

The amidase from Rhodococcus rhodochrous J1, which hydrolyzes an amide to an acid and ammonium, was surprisingly found to catalyze the hydrolytic cleavage of the C-N triple bond in a nitrile to form an acid and ammonium stoichiometrically. The amidase exhibited a Km of 3.26 mM for benzonitrile in contrast to that of 0.15 mM for benzamide as the original substrate, but the Vmax for benzonitrile was about 116000 of that for benzamide. A mutant amidase containing alanine instead of Ser195, which is essential for amidase catalytic activity, showed no nitrilase activity, demonstrating that this residue plays a crucial role in the hydrolysis of nitriles as well as amides.

Identification of active sites in amidase: evolutionary relationship between amide bond- and peptide bond-cleaving enzymes

Mainly based on various inhibitor studies previously performed, amidases came to be regarded as sulfhydryl enzymes. Not completely satisfied with this generally accepted interpretation, we performed a series of site-directed mutagenesis studies on one particular amidase of Rhodococcus rhodochrous J1 that was involved in its nitrile metabolism. For these experiments, the recombinant amidase was produced as the inclusion body in Escherichia coli to greatly facilitate its recovery and subsequent purification. With regard to the presumptive active site residue Cys203, a Cys203 --> Ala mutant enzyme still retained 11.5% of the original specific activity. In sharp contrast, substitutions in certain other positions in the neighborhood of Cys203 had a far more dramatic effect on the amidase. Glutamic acid substitution of Asp191 reduced the specific activity of the mutant enzyme to 1.33% of the wild-type activity. Furthermore, Asp191 --> Asn substitution as well as Ser195 --> Ala substitution completely abolished the specific activity. It would thus appear that, among various conserved residues residing within the so-called signature sequence common to all amidases, the real active site residues are Asp191 and Ser195 rather than Cys203. Inasmuch as an amide bond (CO-NH2) in the amide substrate is not too far structurally removed from a peptide bond (CO-NH-), the signature sequences of various amidases were compared with the active site sequences of various types of proteases. It was found that aspartic acid and serine residues corresponding to Asp191 and Ser195 of the Rhodococcus amidase are present within the active site sequences of aspartic proteinases, thus suggesting the evolutionary relationship between the two.

Cloning and nucleotide sequence of fosfomycin biosynthetic genes of Streptomyces wedmorensis

The biosynthetic pathway for production of the antibiotic fosfomycin by Streptomyces wedmorensis consists of four steps including the formation of a C-P bond and an epoxide. Fosfomycin production genes were cloned from genomic DNA using S. wedmorensis mutants blocked at different steps of the biosynthetic pathway. Four genes corresponding to each of the biosynthetic steps were found to be clustered in a DNA fragment of about 5 kb. Nucleotide sequencing of a large fragment revealed the presence of ten open reading frames, including the four biosynthetic genes and six genes with unknown functions.

[Morphologic and clinical aspects of chronic gastric erosions]

Chronic erosions of the stomach are mostly papular lesions of the gastric mucosa with large base, 0.5-1 cm in diameter, often with superficial central depression covered with fibrin, less frequently without it. The typical site of lesion is the antrum the chronic erosions are here manifold, solitary forms are infrequent. In the course of 5694 gastroduodenoscopies the authors observed in 198 patients (5.2%) typical endoscopic picture of chronic erosions. In biopsy samples volcano-type lesions of the mucous membrane characteristic of the disease were found. According to the results the chronic erosions of the stomach are lesions of aspecific symptomatology, the disturbance of the mucosal barrier cannot be made probable. It is important to know the morphological characteristics of the rather frequent independent entity also for separating it from adenomas. Malignant transformation was not found in the material of the authors.