Bone morphogenetic protein 1 is an extracellular processing enzyme of the laminin 5 gamma 2 chain

Epithelial cells maintained in culture medium containing low calcium proteolytically process laminin 5 (alpha3beta3gamma2) within the alpha3 and gamma2 chains (). Experiments were designed to identify the enzyme(s) responsible for the laminin 5 processing and the sites of proteolytic cleavage. To characterize the nature of laminin 5 processing, we determined the N-terminal amino acid sequences of the proteolytic fragments produced by the processing events. The results indicate that the first alpha3 chain cleavage (200-l65 kDa alpha3) occurs within subdomain G4 of the G domain. The second cleavage (l65-l45 kDa alpha3) occurs within the lIla domain, 11 residues N-terminal to the start of domain II. The gamma chain is cleaved within the second epidermal growth factor-like repeat of domain Ill. The sequence cleaved within the gamma2 chain matches the consensus sequence for the cleavage of type I, II, and III procollagens by bone morphogenetic protein-1 (BMP-1), also known as type I procollagen C-proteinase (). Recombinant BMP-1 cleaves gamma2 in vitro, both within intact laminin 5 and at the predicted site of a recombinant gamma2 short arm. alpha3 is also cleaved by BMP-1 in vitro, but the cleavage site is yet to be determined. These results show the laminin alpha3 and gamma2 chains to be substrates for BMP-1 in vitro. We speculate that gamma2 cleavage is required for formation of the laminin 5-6 complex and that this complex is directly involved in assembly of the interhemidesmosomal basement membrane. This further suggests that BMP-1 activity facilitates basement membrane assembly, but not hemidesmosome assembly, in the laminin 5-rich dermal-epidermal junction basement membrane in vivo.

Interaction among NMDA receptor-, NMDA glycine site- and AMPA receptor antagonists in spinally mediated analgesia

PURPOSE

The NMDA (N-methyl-D-aspartate) receptor antagonists and the NMDA glycine site antagonists given alone have minimal effects on acute nociception. In contrast, the AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptor antagonists have a major role in acute nociception. We investigated the interactions among these three antagonists in acute nociception.

METHODS

Sprague-Dawley rats (250-300 g) were implanted with chronic lumbar intrathecal catheters and were tested for their thermal withdrawal response using the hot plate test after intrathecal administration of AP-5 (NMDA receptor antagonist), ACEA 1021 (NMDA glycine site antagonist), or ACEA 2085 (AMPA receptor antagonist). The combinations of these three agents were also tested.

RESULTS

Intrathecal administration of ACEA 2085 had a dose dependent analgesic effect while intrathecal AP-5 or ACEA 1021 could not induce dose dependent effect. Co-administration of AP-5 10 microg and ACEA 2085 intrathecally showed no changes in the thermal response latency compared with ACEA 2085 alone. ACEA 1021, 12 microg, and AP-5 showed left-ward shift of the dose effect curve only with small doses of AP-5 (1 microg, 3 microg). Only the smallest dose of ACEA 2085 (0.1 ng) with ACEA 1021 12 microg induced antinociception compared with that of ACEA 2085 alone.

CONCLUSIONS

The combination of the NMDA glycine site antagonist and low doses of the NMDA receptor antagonist or the AMPA receptor antagonist increased the analgesic effect on acute thermal nociception with increased side effects, while the NMDA receptor antagonist and the AMPA receptor antagonist had no such interaction.

In vivo detection of human vascular endothelial growth factor promoter activity in transgenic mouse skin

We have generated transgenic mice expressing green fluorescent protein (GFP) driven by 2.453-kb (-2,362 to +91) of the 5'-upstream region of the human vascular endothelial growth factor (VEGF) promoter to monitor changes of VEGF gene transcription in situ. Neonatal transgenic mice exhibited GFP-derived fluorescence in tissues that have been previously reported to express VEGF mRNA expression, including lung, cartilage, and brain. In normal skin during postnatal development, moderate fluorescence was observed in the upper epidermis and, more prominently, in the outer root sheath keratinocytes of hair follicles. Strong up-regulation of GFP fluorescence was observed in the hyperplastic epidermis of the wound edge at 48 hours after wounding, whereas little GFP fluorescence was detected in the dermis. In situ hybridization confirmed an identical expression pattern of VEGF mRNA in these wounds. Topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA) induced strong VEGF-GFP expression in suprabasal epidermis. Little or no fibroblast-derived fluorescence was seen both in the wound model and after TPA application. By confocal laser microscopy, increased GFP fluorescence was detectable in the epidermis of intact mouse ear skin as early as 6 hours after topical TPA treatment. Importantly, GFP fluorescence was also measurable in the skin of living transgenic mice. These results resolve the present controversy regarding the ability of VEGF-GFP transgenic mouse models to correctly reflect established patterns of VEGF expression, and show the model to be a powerful tool for the in vivo monitoring of VEGF gene expression.

[General anesthesia for a patient with Cornelia de Lange syndrome]

Cornelia de Lange syndrome involves anomalies in cardio-vascular and musculo-skeletal systems, and mental retardation. In addition, a patient with this syndrome shows a peculiar look. A 22-year-old woman with Cornelia de Lange syndrome underwent general anesthesia twice. She has a small mouth, thin lips, a short neck, short limbs, and stiffness of the neck and some joints associated with slight mental retardation. She was scheduled for arthroscopy and then for rotational acetabular osteotomy and valgus osteotomy. The maximum distance between the upper and lower incisors was 34 mm, when she opened her mouth. Anesthesia was induced with sevoflurane increased slowly to 7.0% in oxygen 6 l.min-1 in both procedures. After the administration of 4% lidocaine 3.5 ml into the pharynx, orotracheal intubation was attempted, but was not successful. Then blind naso-tracheal intubation was performed successfully under spontaneous respiration under sevoflurane-oxygen inhalation. The induction of anesthesia with sevoflurane under spontaneous respiration was useful for blind naso-tracheal intubation in a case with difficult intubation such as in Cornelia de Lange syndrome.

[Combined intercostal nerve block and epidural anesthesia in a patient with severe aortitis syndrome]

A 74-year-old woman with aortitis syndrome was scheduled for mastectomy. Her left vertebral artery was totally occluded and left carotid arteries, left subclavia artery and bilateral common renal arteries were occluded. For anesthesia a catheter was inserted into the epidural space between T3 and T4. Lidocaine 80 mg (2%, 4 ml) was administered epidurally. Then intercostal nerve block was performed with bupivacaine 15 mg (0.5%, 3 ml) at T3 and T4 level. Local infiltration of lidocaine 50 mg (1%, 5 ml) was added. During the surgery, hemodynamics were stable and no neurological symptom was observed. Epidural anesthesia alone might be sufficient for anesthesia if higher concentration of local anesthetic was used. However, to avoid hemodynamic change, we used 1% lidocaine and added intercostal nerve block. We conclude that combined intercostal nerve block and epidural anesthesia was useful for a patient with severe aortitis syndrome in oder to monitor consciousness to detect cerebral ischemia and to avoid hemodynamic instability.

Involvement of bradykinin in acute exercise-induced increase of glucose uptake and GLUT-4 translocation in skeletal muscle: studies in normal and diabetic humans and rats

Acute exercise induces glucose uptake in skeletal muscle in vivo, but the molecular mechanism of this phenomenon remains to be identified. In this study, we evaluated the involvement of bradykinin in exercise-induced glucose uptake in humans and rats. In human studies, plasma bradykinin concentrations increased significantly during an ergometer exercise (20 minutes) in 8 healthy normoglycemic subjects and 6 well-controlled type 2 diabetic patients (mean hemoglobin A1c [HbA1c], 6.4% +/- 0.6%), but not in 6 poorly controlled type 2 diabetics (mean HbA1c, 11.6% +/- 2.6%). In rat studies, plasma bradykinin concentrations also significantly increased after 1 hour of swimming in nondiabetic and mildly diabetic (streptozotocin [STZ] 45 mg/kg intravenously [IV]) rats, but not in rats with severe diabetes (STZ 65 mg/kg IV). Glucose influx (maximum velocity [Vmax]) and GLUT-4 translocation in skeletal muscle of nondiabetic rats significantly increased after 1 hour of swimming, but these increases were abrogated by subcutaneous infusion of bradykinin B2 receptor antagonist HOE-140 (400 microg x kg(-1) x d(-1)). Insulin-stimulated tyrosine phosphorylation and phosphatidylinositol (PI) 3-kinase activity in response to insulin injection (20 U/kg IV) in the portal vein were significantly attenuated in exercised rats pretreated with HOE-140 compared with saline-treated exercised rats. Our results suggest that plasma bradykinin concentrations increase in response to acute exercise and this increase is affected by blood glucose status in diabetic patients. Moreover, the exercise-induced increase in bradykinin may be involved in modulating exercise-induced glucose transport through an increase of GLUT-4 translocation, as well as enhancement of the insulin signal pathway, during the postexercise period in skeletal muscle, resulting in a decrease of blood glucose.

Role of carbohydrate antigens sialyl Lewis (a) (CA19-9) in bronchoalveolar lavage in patients with pulmonary fibrosis

BACKGROUND

It has been reported that carbohydrate antigen sialyl Lewis (a) (CA19-9) levels are elevated in serum as well as in bronchoalveolar lavage fluid (BALF) of patients with pulmonary fibrosis. However, the biological significance of CA19-9 is unclear.

OBJECTIVE

The purpose of the present study was to evaluate correlations between CA19-9 levels in BALF and several biochemical as well as clinical parameters in patients with pulmonary fibrosis. In addition, biological functions of CA19-9 were also examined.

METHODS

We studied 24 patients with a diagnosis of pulmonary fibrosis: 16 with idiopathic pulmonary fibrosis (IPF) and 8 with pulmonary fibrosis associated with a collagen vascular disorder (PF-CVD). In BALF, carbohydrate antigens sialyl Lewis (a) (CA19-9), elastase: alpha(1)-proteinase inhibitor complex (E-PI), hepatocyte growth factor (HGF), LDH, IgG, IgA, albumin, and cell differentiation were measured. We also evaluated the effects of CA19-9 on neutrophil functions.

RESULTS

CA19-9/albumin levels in BALF significantly correlated with HGF/albumin, elastase/albumin, LDH/albumin, total number of alveolar macrophages, and total number of neutrophils. Purified CA19-9 had a chemotactic activity for neutrophils. In addition, neutrophil chemotactic activity to C5a, fMLP, and interleukin 8 was significantly stimulated after incubation with purified CA19-9. Furthermore, CA19-9 increased the expression of CD15s on neutrophils.

CONCLUSIONS

Our data demonstrated (i) CA19-9 in BALF correlated with other markers of inflammation in pulmonary fibrosis, and (ii) CA19-9 can modify neutrophil functions. These results suggest that CA19-9 may play a role in the process of lung injury in patients with pulmonary fibrosis.

Bradykinin enhances insulin receptor tyrosine kinase in 32D cells reconstituted with bradykinin and insulin signaling pathways

We have previously shown that bradykinin potentiated insulin-induced glucose uptake through GLUT4 translocation in canine adipocytes and skeletal muscles. The aim of this study was to determine the molecular mechanism of bradykinin enhancement of the insulin signal. For this purpose, 32D cells, which express a limited number of insulin receptors and lack endogenous bradykinin B2 receptor (BK2R) or insulin receptor substrate (IRS)-1 were transfected with BK2R cDNA and/or insulin receptor cDNA and/or IRS-1 cDNA, and analyzed. In 32D cells that expressed BK2R and insulin receptor (32D-BKR/IR), bradykinin alone had no effect on the phosphorylation of the insulin receptor, but it enhanced insulin-stimulated tyrosine phosphorylation of the insulin receptor. In 32D cells that expressed BK2R, insulin receptor and IRS-1 (32D-BKR/IR/IRS1), bradykinin also enhanced insulin-stimulated tyrosine phosphorylation of the insulin receptor and IRS-1. An increase in insulin-stimulated phosphorylation of IRS-1 by treatment with bradykinin in 32D-BKR/IR/IRS1 cell was associated with increased binding of 85 kD subunit of phosphatidylinositol 3 (PI 3)-kinase and increased IRS-1 associated PI 3-kinase activity. These effects of bradykinin were not observed in 32D cells which lack the expression of BK2R (32D-IR/IRS1) or insulin receptor (32D-BKR/IRS1). Furthermore, tyrosine phosphatase activity against insulin receptor beta-subunit in plasma membrane fraction of 32D-BKR/IR cells was significantly reduced by bradykinin, suggesting that the effect of bradykinin was in part mediated by inhibition of protein tyrosine phosphatase(s). Our results clearly demonstrated that bradykinin enhanced insulin-stimulated tyrosine kinase activity of the insulin receptor and downstream insulin signal cascade through the BK2R mediated signal pathway.

[A case of Collet-Sicard syndrome caused by skull base metastasis of prostate carcinoma]

A case of Collet-Sicard Syndrome caused by skull base metastasis of prostate carcinoma is reported. A fifty-five years old man presenting multiple lymph node and bone metastases of prostate carcinoma was treated with LH-RH agonist and Flutamide, which induced transient decrease in serum PSA levels and size of lymph node metastases. After 8 months of the treatment, the patient started complaining headache, dysphagia and dysarthria. Brain CT and MRI demonstrated a soft tissue mass replacing left pyramidal bone and occipital bone around left jugular foramen. The tumor was diagnosed as skull base metastasis of the prostate carcinoma and was treated with 50Gy of radiation. The symptom improved after the radiation but died of the disease in 4 months. The autopsy revealed the skull base metastasis of the prostate carcinoma and the tumor was proved to be poorly differentiated adenocarcinoma, which was positively stained by anti-PSA antibody. The case showed cranial nerve palsy of IX to XII, which is usually called Collet-Sicard syndrome. This is the third case report of Collet-Sicard syndrome caused by the skull base metastasis of prostate carcinoma, and it is the first case in Japan.

Hepatocyte growth factor is a predominant chemoattractant for gingival epithelial cells produced by radicular cyst-derived fibroblast-like cells

To clarify whether fibroblasts could be involved in the pathogenesis of periodontal pocket formation, the chemotactic activity of radicular cyst-derived fibroblast-like cell (RCF)-conditioned medium (RCF-CM) for gingival epithelial cells was examined using a modified Boyden chamber assay. RCF-CM possessed significant chemotactic activity, which was decreased markedly by treatment with anti-human hepatocyte growth factor (HGF) antibody. Furthermore, the chemotactic activity of RCF-CM was well correlated with HGF content. These results show that the RCF secrete an HGF-like factor, and suggest that such a factor derived from periodontal fibroblasts might play a role in epithelial apical migration in periodontitis.

Interaction between intrathecal morphine and glutamate receptor antagonists in formalin test

The analgesic interaction between intrathecally administered morphine and the NMDA receptor antagonist, ((+/-)-2-amino-5-phosphonopentanoic acid; AP-5), the NMDA receptor glycine site antagonist, (5-nitro-6,7-dichloro-2,3-quinoxaline dion; ACEA 1021), or the AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) receptor antagonist (ACEA 2752) in the formalin test was investigated with a rat model of chronic lumbar intrathecal catheterization. After obtaining dose-response curves for each agent, combinations of morphine and AP-5, ACEA 1021 or ACEA 2752 were tested for their effect on the number of flinches in the formalin test and for associated side-effects, such as motor disturbances, flaccidity, and agitation/allodynia. Using isobolographic analyses, a potent analgesic synergy was observed with decreased side-effects between morphine and ACEA 2752 or AP-5. ACEA 1021 increased the analgesic effect of low-dose morphine. Spinal mu-opioid receptor activation and NMDA or AMPA receptor antagonism showed a synergistic antinociception against tonic pain. These results suggest an important direction in the management of inflammatory pain.

Is protease inhibitor a choice for the treatment of pre- or mild disseminated intravascular coagulation?

OBJECTIVE

To investigate the effect of a protease inhibitor, gabexate mesylate, on patients with pre- or mild disseminated intravascular coagulation (DIC) in comparison with a control group receiving no anticoagulation therapy.

DESIGN

Prospective, randomized, controlled study.

SETTING

General intensive care unit at a general hospital.

PATIENTS

Adult patients (40) with a DIC score between 6 and 8 (pre- or mild DIC).

INTERVENTIONS

In 20 patients, gabexate mesylate (2 mg/kg/hr) was administered as 2 mL/hr in saline (treated group) and in another 20 patients, saline (2 mL/hr; control group) was administered during the study (7 days).

MEASUREMENTS AND MAIN RESULTS

The following variables were determined at the time of admission to the intensive care unit before treatment and 1, 3, 5, and 7 days thereafter: platelet count, antithrombin III activity, serum or plasma concentrations of fibrinogen, fibrin degradation product, D-dimer, fibrin monomer, thrombin-antithrombin III complex, and plasmin-plasmin inhibitor complex, prothrombin time ratio, and DIC score. Two patients in the treated group and four in the control group were excluded from the study because they died during the study; therefore, 34 patients were analyzed. The measured variables of coagulation and fibrinolysis were not significantly different between the two groups, except for the D-dimer on day 3 (the treated group showed a higher concentration). D-dimer concentration and DIC score went down more quickly in the control group than the treated group, but not significantly. The mortality rate at 1 month was 40% (8 of 20) in the treated group and 35% (7 of 20) in the control group, without any differences between the two groups.

CONCLUSIONS

In a limited number of patients (n = 34), gabexate mesylate (2 mg/kg/hr) could not inhibit coagulation or fibrinolysis and gabexate mesylate could not improve the DIC score or mortality rate in pre- or mild DIC.

[Coronary artery spasm during vascular surgery]

A 56-year-old male with arteriosclerosis obliterans was scheduled for aorto-biiliac artery bypass graft surgery. He had episodes of chest pain lasting for several minutes. Preoperative electrocardiogram (ECG) and myocardiac scintigram showed no abnormal findings. Anesthesia was induced with thiopental 225 mg, fentanyl 100 micrograms and tracheal intubation was facilitated with vecuronium 10 mg. Anesthesia was maintained with O2 2 l.min-1, N2O 4 l.min-1, sevoflurane 0.5-1% and epidural injection of 1% mepivacaine 6-10 ml.hr-1. Nitroglycerin was infused at a rate of 0.125 microgram.kg-1.min-1. During surgery, a transient elevation of the ST segment occurred three times in lead II of the ECG. For the first episode with decrease in blood pressure at declamping the external iliac artery, administration of phenyrephrine 100 micrograms improved ST segment elevation in ECG. For the second event with a slight decrease in blood pressure, an increased dose of nitroglycerin decreased ST segment elevation. The third incident with increased blood pressure and heart rate was alleviated by decreasing the dose of dopamine. Postoperative ECG and serum creatine kinase level were within normal limits. These three episodes of ST segment elevation might be due to coronary spasms induced by decreased blood pressure or increased blood pressure and heart rate.

Mechanism-based inactivation of human dihydropyrimidine dehydrogenase by (E)-5-(2-bromovinyl)uracil in the presence of NADPH

Purified recombinant human dihydropyrimidine dehydrogenase (hDPD) was incubated with (14)C-labeled (E)-5-(2-bromovinyl)uracil ([(14)C]BVU) in the presence of NADPH to investigate a possible mechanism in the 18 patient deaths caused by interactions of 5-fluorouracil prodrugs with the new oral antiviral drug, sorivudine. BVU is formed from sorivudine by gut flora and absorbed through intestinal membrane. hDPD, a rate-limiting enzyme for the catabolism of 5-fluorouracil and endogenous pyrimidines in the human, was NADPH dependently radiolabeled and inactivated by [(14)C]BVU. Two radioactive tryptic fragments, I and II, isolated from radiolabeled hDPD were found by complete amino acid sequencing to originate from a common regional amino acid sequence located at positions 656 (Lys) to 678 (Arg) for I and positions 657 (Ser) to 678 (Arg) for II. However, only Cys(671), which should be present in the peptides, was not identified by amino acid sequencing. Mass spectrometric analysis of the tryptic fragments indicated that the sulfhydryl group of Cys(671) in the hDPD was modified with 5, 6-dihydro-5-(2-bromoethylydenyl)uracil (BEDU), a putative allyl bromide type of reactive molecule, to form a sulfide bond with loss of hydrogen bromide. The Cys(671) sulfide bearing the debrominated BEDU had a 5,6-dihydrouracil ring highly strained by the exocyclic double bond at the 5-position, so that it underwent facile hydrolytic ring fission with alkali and heated acid treatments. A new proposal is also made for the amino acid sequence of the pyrimidine-binding domain, including Cys(671), of DPD in the human and other species.

[In vitro activity of faropenem against beta-lactamase producing clinical isolates]

Each 20 strains of beta-lactamase producing methicillin susceptible Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Haemophilus influenzae, Moraxella (Branhamella) catarrhalis, and Bacteroides fragilis group were used as the test strains. Drug susceptibility of these strains to faropenem (FRPM), cefdinir, cefditoren, cefcapene, cefteram, cefaclor, and ampicillin was determined by an agar dilution method according to the NCCLS guideline M100-S9. beta-Lactamase activity of the test strains was determined by a spectrophotometric method. In the present study, FRPM was highly active against beta-lactamase-producing strains, and no close correlation was found between the MICs of FRPM for the test strains and their beta-lactamase activities. These results suggest that FRPM has potential in successful application for the treatment of infectious diseases with various types of bacterial pathogens including beta-lactamase producing strains.

[The necessity and the efficacy of the second administration of midazolam for sedation during spinal anesthesia]

We investigated the necessity of the second additional administration of intravenous midazolam for sedation during spinal anesthesia and the adequate dose if necessary. Fifty patients with ages between 35 to 70 years for spinal anesthesia were administered midazolam 0.05 mg.kg-1 intravenously during surgery. Thirty-four patients opened their eyes spontaneously and to these patients midazolam 1 mg was administered every three minutes until patients closed their eyes. All 34 patients closed their eyes with 1 mg of midazolam. Patients opened their eyes again at 47 +/- 16 minutes (mean +/- SD) after the first dose (0.05 mg.kg-1) and at 24 +/- 14 minutes after the second dose (1 mg). The decreases in blood pressure, heart rate and percutaneous arterial oxygen saturation after the administration of midazolam were less after the second administration than those after the first one. The percent of patients with amnesia was larger in the patients with only first administration than those with the second dose. These results suggest that the additional dose of midazolam is not necessary after intravenous midazolam 0.05 mg.kg-1 until patients open their eyes and the additional 1 mg is useful even after patients have opened their eyes.

Comparison of the pharmaceutical properties of sustained-release gel beads prepared by alginate having different molecular size with commercial sustained-release tablet

Spherical alginate gel beads containing pindolol were prepared using three types of sodium alginate with different molecular size. The rate of gelation of sodium alginate in calcium chloride solution was in the range of 1.0 to 1.3 h-1 among the used three alginates, but the amount of water squeezed from the alginate gel beads during gelation increased from 5 to 40% with increasing molecular size of the alginate. The beads prepared were similar in diameter (1.2 mm after drying), weight (0.9 mg/bead), calcium content (27-29 micrograms/bead) and pindolol content (40-45%). Pindolol was rapidly released from all the alginate gel beads at pH 1.2 owing to the high solubility of pindolol, in spite of non-swelling of beads. On the other hand, pindolol release from alginate gel beads at pH 6.8 was dependent on the swelling of the beads and was significantly depressed compared to drug powder. Interestingly, the release rate of pindolol and the swelling rate of beads were markedly slow for gel beads prepared by low molecular size alginate. However, when the alginate gel beads were administered orally to beagle dogs, the serum levels of pindolol showed sustained-release profiles, depending on the molecular size of the alginate. The in vivo absorption of pindolol from alginate gel beads did not reflect their in vitro release profiles, because of a physical strength of beads in the intestinal tract. Furthermore, the in vivo and in vitro release of pindolol from alginate gel beads were compared with a commercial sustained-release tablet, Carvisken showed a rapid release of 50% of content in pH 1.2 fluid and residual 50% of pindolol were easily dissolved at pH 6.8. Although the release characteristics of pindolol from Carvisken and the alginate gel beads were completely different, the serum levels of pindolol in human volunteers were comparable.

N-Glycans protect proteins from protease digestion through their binding affinities for aromatic amino acid residues

It was previously revealed [Yamaguchi, H., Nishiyama, T., and Uchida, M. (1999) J. Biochem. 126, 261-265] that N-glycans of both the high-mannose and complex types have binding affinity for aromatic amino acid residues. This study shows that free N-glycans protect proteins from protease digestion through their binding affinities for the aromatic amino acid residues exposed on protein molecules. Protease digestion of bovine pancreatic RNase A and bovine a-lactalbumin was depressed in solutions (1 mM or so) of free N-glycans of both the high-mannose and complex types. The increasing order of the protective effects of the N-glycans paralleled that of their affinities for aromatic amino acid residues; and the presence of aromatic amino acids practically abolished the protective effects of the N-glycans. The N-glycans also depressed the protease digestion of metallothionein, an aromatic amino acid-free protein, in agreement with the observation that the N-glycans also interact with the solvent-exposed aromatic amino acid residues of the proteases. Thus it seems probable that the N-glycans protect proteins from protease digestion by steric hindrance attributable to their binding affinity for the solvent-exposed aromatic amino acid residues of both substrate proteins and proteases.

Tagged mutagenesis and gene-trap in the moss, Physcomitrella patens by shuttle mutagenesis

The moss, Physcomitrella patens has been used as a useful material in many fields, because of its simple body plan, ease of gene targeting, and other reasons. Although many mutants have been reported, no method to isolate the corresponding genes was reported. We developed a gene tagging and gene-trap system in P. patens by using the shuttle mutagenesis technique, which has been used in the budding yeast. In 5264 tagged lines, 203 mutants with altered developmental or morphological phenotypes were obtained. In 129 of 4757 gene-trap lines, beta-glucuronidase (GUS) activity was detected in some tissue. Although multiple copies of a tag were detected in many tagged lines by Southern analyses, most copies are likely integrated at the same locus according to PCR analyses.

Comparison of infrared thermometer with thermocouple for monitoring skin temperature

OBJECTIVE

To test the hypothesis that the infrared thermometer (Genius) is comparably useful with thermocouples that are routinely used for skin temperature monitoring.

DESIGN

Prospective, controlled, not blinded study.

SETTING

Operating room of a university hospital.

SUBJECTS

Ten healthy male volunteers.

INTERVENTIONS

Volunteers were minimally clothed and were initially warmed by a forced air warmer until they became vasodilated at the finger and the foot for approximately 30 mins. Subsequently, they were kept in the room with no blanket.

MEASUREMENTS AND MAIN RESULTS

Skin temperatures were measured continuously with the Mon-a-Therm thermocouple and were also measured with the Genius thermometer just before and after the warming and subsequently every 10 mins for 70 mins. Forearm and finger-tip skin temperatures and skin-surface temperature gradients (from arm to finger and from calf to toe) measured by the Genius thermometer were compared with those measured by the Mon-a-Therm thermocouple using linear regression and Bland and Altman statistics. Forearm temperature and finger-tip temperature ranged from approximately 31 degrees to approximately 36.5 degrees C (87.8-97.7 degrees F) and approximately 22.5 degrees to approximately 36 degrees C (72.5-96.8 degrees F), respectively. Gradients (from arm to finger and from calf to toe) ranged from approximately -3 degrees to approximately 10 degrees C (26.6-50.0 degrees F) and approximately -3 degrees to approximately 11 degrees C (26.6-51.8 degrees F), respectively. Correlations between the temperatures measured by the Genius thermometer and those by the Mon-a-Therm thermocouple were similar and reliable. The correlation coefficients were as follows: 0.78 at forearm, 0.97 at finger-tip, and 0.97 at skin-surface temperature gradients.

CONCLUSIONS

The infrared thermometer with a special probe is useful to measure the change of skin-surface temperatures and to evaluate the severity of shock in patients.

Importance of disulfide bridge formation on folding of phospholipase D from Streptomyces antibioticus

The effects of redox conditions on the folding of phospholipase D (PLD) of Streptomyces antibioticus were investigated. Although the enzyme was very stable even in the presence of 1.0 M guanidinehydrochloride (Gdn-HCl), the coexistence of dithiothreitol (DTT) and Gdn-HCl inactivated the enzyme completely. The inactivated enzyme recovered its activity by dialysis in which DTT was removed prior to Gdn-HCl, whereas its activity was not recovered when Gdn-HCl was removed prior to DTT. In vitro protein synthesis was used for further analyses of the folding process. Active PLD was synthesized in the absence of DTT. The activity increased as the protein synthesis proceeded. In contrast, inactive PLD was synthesized in the presence of DTT. The inactive PLD could not be effectively activated by simple removal of the reductant, while incubation with Gdn-HCl and subsequent removal of DTT followed by that of Gdn-HCl was a much more effective method for the synthesis of active enzymes. From these results, it is suggested that: (i) PLD contains disulfide bridge(s), which is (are) necessary for maintaining its tertiary structure, (ii) correct formation of the disulfide bridge(s) is a critical step in the early stage of the (re)folding process, and (iii) the disulfide bridge(s) further facilitate the folding process, resulting in the synthesis of the active enzymes with the correct structure.

Reproducibility of the drug effects over time on chronic lumbar epidural catheterization in rats

Chronically implanted epidural catheters lead to a reaction that impedes drug action. The purpose of this study in a rat model with chronically implanted epidural catheters was to investigate the change in opiate activity and histology over time with this model. A skin incision of 1-2 cm was made at the T 13 level on the back of male Sprague-Dawley rats under halothane anesthesia. Muscles were dissected bluntly from the vertebrae, and the intervertebral ligament was cut to insert an epidural catheter (polyethylene tube, outer diameter of 0.14 mm) 2-cm caudally. The longer portion of the catheter was passed through a trocar subcutaneously to exit the dorsal neck area. One, two, and six days after catheterization, the effects of morphine on thermal stimulation using the hot-box test and histology were investigated. Analgesic effects of morphine 6 days after catheterization were significantly less than those on the first and second days. Histologically, evidence of inflammation around the catheter was noted as early as 4 h after catheterization. Pericatheter fibrosis was severe after 2 days. We conclude that this model of chronic epidural catheterization in the rat evoked a histologically defined, pharmacodynamically significant, local reaction 2 to 6 days after catheter implantation.

IMPLICATIONS

A rat model with chronically implanted epidural catheters should be used for testing the analgesic effects of drugs within two days after catheterization.

Cerebrovascular carbon dioxide reactivity during general anesthesia: a comparison between sevoflurane and isoflurane

We compared cerebrovascular carbon dioxide reactivity during the administration of sevoflurane and isoflurane anesthesia by measuring cerebral blood flow velocity (CBFV) as an indirect measurement of cerebral blood flow. Thirty patients, 20-70 yr old, undergoing lower abdominal surgery and without known cerebral or cardiovascular system disease, were randomly assigned to either sevoflurane or isoflurane treatment groups. Anesthesia was induced with thiopental 5 mg/kg IV and maintained with either sevoflurane or isoflurane in 67% nitrous oxide and oxygen. The CBFV and pulsatility index (PI) of the left middle cerebral artery were monitored with transcranial Doppler. The P(ETCO)2 was increased stepwise from 20 to 50 mm Hg by changing the respiratory rate with a constant tidal volume. At every 5-mm Hg stepwise change in P(ETCO)2, CBFV and PI were recorded. CBFV increased with increasing P(ETCO)2. CBFV was significantly smaller in the isoflurane group at P(ETCO)2 = 20-40 mm Hg than in the sevoflurane group. The rate of change of CBFV with changes in CO2 was larger in the isoflurane group than in the sevoflurane group. PI was constant over time and was not different between groups. In conclusion, hypocapnia-induced reduction of intracranial pressure might be more effective during the administration of isoflurane than sevoflurane.

IMPLICATIONS

Changes in cerebral blood flow caused by the changes of carbon dioxide tension are greater during the administration of isoflurane anesthesia compared with sevoflurane anesthesia. Attempts to decrease intracranial pressure by decreasing carbon dioxide tension may be more successful during isoflurane than sevoflurane anesthesia administration.

The systemically administered competitive AMPA receptor antagonist, YM872, has analgesic effects on thermal or formalin-induced pain in rats

A new competitive alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor antagonist, (2,3-dioxo-7-[1H-imidazol-1-yl]-6-nitro-1,2,3,4-tetrahydro-1-quinoxal inyl) acetic acid (YM872) has analgesic effects on acute thermal- and formalin-induced nociception by intrathecal administration. The purpose of this study was to determine the analgesic effects of systemically administered YM872 in both acute thermal- and irritant-induced pain. Sprague-Dawley rats were tested for tail withdrawal response by the tail flick test and for paw flinches by formalin injection after intraperitoneal administration of YM872. The tail flick latency increased dose-dependently with a 50% effective dose value of 156.3 microg. The number of flinches in both first and second phases of the formalin test decreased with increasing the dose of YM872. The 50% effective dose values were 1.0 microg in the first phase and 38.7 microg in the second phase. Transiently, intraperitoneal administration of 1 and 10 mg of YM872 induced motor disturbance and 10 mg induced loss of pinna reflex. We conclude that intraperitoneal administration of YM872 had analgesic effects on both acute thermal- and formalin-induced nociceptions in rats. Transient motor disturbance and loss of pinna reflex occurred only with large doses.

IMPLICATIONS

Intraperitoneally administered YM872, a new alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor antagonist, had analgesic effects on thermal- and formalin-induced pain in rats. Larger doses induced transient motor disturbance and loss of pinna reflex mediated in the brain.

[High-dose chemotherapy with peripheral blood stem cell autotransplantation for patients with poor-risk testicular germ cell tumors--pilot study of the Japan Blood Cell Transplantation Study Group]

The efficacy and toxicity of a single cycle of high-dose chemotherapy with peripheral blood stem cell autotransplantation (PBSCT) in patients with poor-risk testicular germ cell tumors (GCT) enrolled in the Japan Blood Cell Transplantation Study Group was investigated. Previously untreated poor-risk testicular GCT patients were treated with BEP therapy (cisplatin, etoposide and bleomycin) with or without high-dose chemotherapy (carboplatin, etoposide and ifosphamide) followed by PBSCT. Patients were qualified for a change to high-dose chemotherapy if elevated serum tumor markers (human chorionic gonadotropin-beta, alpha-fetoprotein and lactate dehydrogenase) was observed after 3 cycles of BEP therapy. Eighteen patients were treated with BEP therapy alone and 16 with BEP and high-dose chemotherapy. At the completion of high-dose chemotherapy, all tumor markers had returned to normal in 6 patients. Among them, 1 had only teratoma found at resection and 5 had carcinoma resected. Nine patients who had persistent elevation of any tumor marker were treated with high-dose chemotherapy or another anticancer drug. Thirteen are alive (81%) and 9 (56%) are continuously disease-free at a median follow up of 11 months. The median time from PBSCT to a granulocyte count > 500/microL was 9.5 days and to a platelet count > 50,000/microL was 13 days.