Residues in the 1A rod domain segment and the linker L2 are required for stabilizing the A11 molecular alignment mode in keratin intermediate filaments

Both analyses of x-ray diffraction patterns of well oriented specimens of trichocyte keratin intermediate filaments (IF) and in vitro cross-linking experiments on several types of IF have documented that there are three modes of alignment of pairs of antiparallel molecules in all IF: A11, A22 and A12, based on which parts of the major rod domain segments are overlapped. Here we have examined which residues may be important for stabilizing the A11 mode. Using the K5/K14 system, we have made point mutations of charged residues along the chains and examined the propensities of equimolar mixtures of wild type and mutant chains to reassemble using as criteria: the formation (or not) of IF in vitro or in vivo; and stabilities of one- and two-molecule assemblies. We identified that the conserved residue Arg10 of the 1A rod domain, and the conserved residues Glu4 and Glu6 of the linker L2, were essential for stability. Additionally, conserved residues Lys31 of 1A and Asp1 of 2A and non-conserved residues Asp/Asn9 of 1A, Asp/Asn3 of 2A, and Asp7 of L2 are important for stability. Notably, these groups of residues lie close to each other when two antiparallel molecules are aligned in the A11 mode, and are located toward the ends of the overlap region. Although other sets of residues might theoretically also contribute, we conclude that these residues in particular engage in favorable intermolecular ionic and/or H-bonding interactions and thereby may play a role in stabilizing the A11 mode of alignment in keratin IF.

Cyclooxygenase (COX) 1 and 2 in normal, inflamed, and ulcerated human gastric mucosa

BACKGROUND AND AIMS

Constitutive cyclooxygenase (COX) 1 is believed to mediate prostaglandin dependent gastric protection. However, gastric mucosa contains cells capable of expressing inducible COX-2. We therefore investigated COX-1 and COX-2 expression, localisation, and activity in normal and abnormal human gastric mucosa.

METHODS

COX-1 and COX-2 distribution was investigated by light and electron microscopic immunohistochemistry and by western blot analysis, and their contribution to prostaglandin (PG)E(2) synthesis using selective enzyme inhibitors.

RESULTS

There was strong parietal cell COX-1 and COX-2 immunoreactivity in all sections and isolated cells, with macrophage and myofibroblast reactivity in some sections. Immunostaining was specifically abolished by antigen absorption. Western blot analysis confirmed COX-1 and 2 expression. COX-1 and COX-2 immunostaining was increased in Helicobacter pylori gastritis, particularly the mid glandular zone and lamina propria inflammatory cells. This was associated with increased ex vivo PGE(2) synthesis (62.4 (13.5) pg/mg v 36.3 (15.5) pg/mg in uninflamed mucosa; p=0. 017) which was significantly inhibited by COX-1 but not COX-2 inhibition. Increased COX-2 immunostaining in macrophages, endothelial cells, and myofibroblasts (with reduced epithelial expression) was seen at the rim of ulcers.

CONCLUSION

COX-2, as well as COX-1, is expressed by normal human gastric mucosa and is increased at the rim of ulcers. Although both are increased with H pylori, COX-1 contributes more than COX-2 to gastric PGE(2) production.

Coiled-coil trigger motifs in the 1B and 2B rod domain segments are required for the stability of keratin intermediate filaments

Many alpha-helical proteins that form two-chain coiled coils possess a 13-residue trigger motif that seems to be required for the stability of the coiled coil. However, as currently defined, the motif is absent from intermediate filament (IF) protein chains, which nevertheless form segmented two-chain coiled coils. In the present work, we have searched for and identified two regions in IF chains that are essential for the stability necessary for the formation of coiled-coil molecules and thus may function as trigger motifs. We made a series of point substitutions with the keratin 5/keratin 14 IF system. Combinations of the wild-type and mutant chains were assembled in vitro and in vivo, and the stabilities of two-chain (one-molecule) and two-molecule assemblies were examined with use of a urea disassembly assay. Our new data document that there is a region located between residues 100 and 113 of the 2B rod domain segment that is absolutely required for molecular stability and IF assembly. This potential trigger motif differs slightly from the consensus in having an Asp residue at position 4 (instead of a Glu) and a Thr residue at position 9 (instead of a charged residue), but there is an absolute requirement for a Glu residue at position 6. Because these 13 residues are highly conserved, it seems possible that this motif functions in all IF chains. Likewise, by testing keratin IF with substitutions in both chains, we identified a second potential trigger motif between residues 79 and 91 of the 1B rod domain segment, which may also be conserved in all IF chains. However, we were unable to find a trigger motif in the 1A rod domain segment. In addition, many other point substitutions had little detectable effect on IF assembly, except for the conserved Lys-23 residue of the 2B rod domain segment. Cross-linking and modeling studies revealed that Lys-23 may lie very close to Glu-106 when two molecules are aligned in the A(22) mode. Thus, the Glu-106 residue may have a dual role in IF structure: it may participate in trigger formation to afford special stability to the two-chain coiled-coil molecule, and it may participate in stabilization of the two-molecule hierarchical stage of IF structure.

Microvascular obstruction and left ventricular remodeling early after acute myocardial infarction

BACKGROUND

The presence of microvascular obstruction (MO) within infarcted regions may adversely influence left ventricular (LV) remodeling after acute myocardial infarction. This study examined whether the extent of MO directly alters the mechanical properties of the infarcted myocardium.

METHODS AND RESULTS

Seventeen dogs underwent 90 minutes of balloon occlusion of the left anterior descending coronary artery, followed by reperfusion. Gadolinium-enhanced perfusion MRI and 3D-tagging were performed 4 to 6 and 48 hours (8 animals) and 10 days (9 animals) after reperfusion. Early increase in LV end-diastolic volume (from 42+/-9 to 54+/-14 mL, P<0.05) between 4 to 6 and 48 hours after reperfusion was predicted by both extent of MO (r=0.89, P<0.01) and infarct size (r=0.83, P<0.01), defined as MRI hypoenhanced and hyperenhanced regions, respectively. Multivariate analysis demonstrated that extent of MO had better and independent value to predict LV volume than overall infarct size. A strong inverse relationship existed between magnitude of first principal strain (r=-0.80, P<0.001) and relative extent of MO within infarcted myocardium. Also, infarcted myocardium involved by extensive areas of MO demonstrated reductions of circumferential (r=-0.61, P<0.01) and longitudinal (r=-0.53, P<0. 05) stretching. Furthermore, significant reductions of radial thickening (9+/-6% versus 14+/-3%, P<0.01) occurred in noninfarcted regions adjacent to infarcts that had increased (>35%) amounts of MO.

CONCLUSIONS

In the early healing phase of acute myocardial infarction, the extent of MO in infarcted tissue relates to reduced local myocardial deformation and dysfunction of noninfarcted adjacent myocardium. Such strain alterations might explain the increased remodeling observed in patients with large regions of MO.

[Electroporation of sperm to introduce foreign DNA into the genome of Pinctada maxima (Jameson)]

Gene transfer was investigated in marine molluscs via electroporated sperm. Sperm of P. maxima (J.) was incubated with linear "all-fish" growth hormone gene (pCAgcGH and pCAgcGHc) for 30 min. Then, mature eggs were in-vitro fertilized with the sperm cells treated with electroporation at 10 kV and 2(7) pulses of six cycles. DNA was extracted from spat and analyzed by PCR and southern blot. The results indicated that the foreign DNA had been transferred into the genome of experimental molluscs. The transgenetic ration was 5.6%, 20% and 50% when 2 micrograms/mL, 6 micrograms/mL and 18 micrograms/mL of foreign DNA was used, respectively. It is suggested that the transferred efficiency is correlated with the amount of the foreign DNA.

Effects of fenoterol and ipratropium on respiratory resistance of asthmatics after tracheal intubation

We have studied the effects of a beta-agonist, fenoterol, and a cholinergic antagonist, ipratropium, on post-intubation total respiratory system resistance (Rrs) in asthmatics who developed increased Rrs after tracheal intubation. Sixteen stable asthmatics in whom Rrs increased after intubation were allocated randomly to receive either 10 puffs of fenoterol (group F) or 10 puffs of ipratropium (group IB) via a metered dose inhaler 5 min after intubation. Anaesthesia was induced and maintained with propofol i.v. Rrs was recorded before treatment and again 5, 15 and 30 min after treatment. Rrs decreased significantly from pretreatment values by mean 53 (SD 8)%, 53 (7)% and 58 (6)% at 5, 15 and 30 min, respectively, in group F, but declined by only 12 (6)%, 15 (4)% and 17 (5)% in group IB. At all times after treatment, patients in the fenoterol group had significantly lower Rrs values than those in the ipratropium group. We conclude that increased Rrs after tracheal intubation in asthmatics can be reduced effectively by treatment with fenoterol. A secondary finding of our study was that even after induction of anaesthesia with propofol, patients with a history of asthma may develop high Rrs.

The mutant growth hormone-releasing hormone (GHRH) receptor of the little mouse does not bind GHRH

The little mouse is a dwarf strain characterized by low levels of GH, pituitary hypoplasia, and an unresponsiveness to treatment with exogenous GHRH. The defect has been mapped to a missense mutation in the GHRH receptor gene that abolishes the function of the receptor, but the mechanism of this inactivation is unknown. Receptor function might be affected at the level of protein expression, maturation and processing, localization to the cell surface, ligand binding, or signaling. In this study, Western blots, using antiserum raised against the GHRH receptor and immunoprecipitation analysis of epitope-tagged receptors, demonstrate that both wild-type and mutant receptor proteins are expressed at equivalent levels in transfected cells. Immunofluorescence analysis of intact and permeabilized cells expressing the epitope-tagged receptors suggests that wild-type and little mouse receptors are similarly localized to the cell surface. A species homologous binding assay was developed and used to show that 125I-mouse GHRH binds with high affinity to the wild-type mouse receptor but not to the little mutant receptor. Consistent with this, the mutant receptor fails to stimulate intracellular cAMP accumulation. Our results demonstrate that the little mutation does not dramatically affect the expression level, glycosylation, or cellular localization of the receptor protein but that it blocks specific GHRH binding, and therefore, signaling does not take place.

Magnetic resonance imaging in acute myocardial infarction

Advances in magnetic resonance imaging (MRI) have led to more widespread utilization of this diagnostic imaging modality in the diagnosis of coronary artery disease. With MRI, the complexity and heterogeneity of myocardial infarcts can be demonstrated. By using this technique, much insight has been gained into the pathophysiologic mechanisms of acute coronary thrombosis and reperfusion. MRI has significant diagnostic potential, particularly if one can combine studies of myocardial function, perfusion, and sodium metabolism with the noninvasive assessment of coronary anatomy and epicardial coronary artery blood flow.

A high molecular weight intermediate filament-associated protein in BHK-21 cells is nestin, a type VI intermediate filament protein. Limited co-assembly in vitro to form heteropolymers with type III vimentin and type IV alpha-internexin

BHK-21 fibroblasts contain type III vimentin/desmin intermediate filament (IF) proteins that typically co-isolate and co-cycle in in vitro experiments with certain high molecular weight proteins. Here, we report purification of one of these and demonstrate that it is in fact the type VI IF protein nestin. Nestin is expressed in several fibroblastic but not epithelioid cell lines. We show that nestin forms homodimers and homotetramers but does not form IF by itself in vitro. In mixtures, nestin preferentially co-assembles with purified vimentin or the type IV IF protein alpha-internexin to form heterodimer coiled-coil molecules. These molecules may co-assemble into 10 nm IF provided that the total amount of nestin does not exceed about 25%. However, nestin does not dimerize with types I/II keratin IF chains. The bulk of the nestin protein consists of a long carboxyl-terminal tail composed of various highly charged peptide repeats. By analogy with the larger neurofilament chains, we postulate that these sequences serve as cross-bridgers or spacers between IF and/or other cytoskeletal constituents. In this way, we propose that direct incorporation of modest amounts of nestin into the backbone of cytoplasmic types III and IV IFs affords a simple yet flexible method for the regulation of their dynamic supramolecular organization and function in cells.

Phenotypic and functional characterisation of myofibroblasts, macrophages, and lymphocytes migrating out of the human gastric lamina propria following the loss of epithelial cells

BACKGROUND

The basement membrane of human colonic mucosa contains numerous discrete pores. We have recently shown that following loss of the surface epithelium, many cells migrate out of the colonic lamina propria via basement membrane pores.

AIMS

To characterise cells migrating out via basement membrane pores of the human gastric lamina propria, following loss of the surface epithelium.

METHODS

Fresh human gastric mucosal samples were completely denuded of epithelial cells and placed in culture. Tissue samples were studied by electron microscopy (EM) and cells by EM, FACS analysis, immunohistochemistry, and reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

EM showed numerous discrete pores (0. 65-8.29 microm in diameter) in the subepithelial basement membrane. During culture of mucosal samples denuded of epithelial cells, lymphocytes, macrophages, and myofibroblasts migrated out of the lamina propria via the basement membrane pores. The lymphocytes were predominantly CD45RO+ and CD69+ T cells. Macrophages were shown to express cyclooxygenase (COX) 1 and 2 enzymes. Myofibroblasts were established in culture and, despite prolonged culture and passage, retained their phenotype. They expressed mRNA and protein for COX 1 and 2 enzymes and their release of prostaglandin E2 was inhibited by selective COX 1 and 2 inhibitors.

CONCLUSIONS

Lamina propria cells migrating out of cultured denuded gastric mucosal samples have been characterised phenotypically and functionally. Such cells would be suitable for studies of their interactions with epithelial cells and also with Helicobacter pylori and its products.

Quantification and time course of microvascular obstruction by contrast-enhanced echocardiography and magnetic resonance imaging following acute myocardial infarction and reperfusion

OBJECTIVES

We aimed to validate contrast-enhanced echocardiography (CE) in the quantification of microvascular obstruction (MO) against magnetic resonance imaging (MRI) and the histopathologic standards of radioactive microspheres and thioflavin-S staining. We also determined the time course of MO at days 2 and 9 after infarction and reperfusion.

BACKGROUND

Postinfarction MO occurs because prolonged ischemia produces microvessel occlusion at the infarct core, preventing adequate reperfusion. Microvascular obstruction expands up to 48 h after reperfusion; the time course beyond 2 days is unknown. Though used to study MO, CE has not been compared with MRI and thioflavin-S, which yield precise visual maps of MO.

METHODS

Ten closed-chest dogs underwent 90-min coronary artery occlusion and reperfusion. Both CE and MRI were performed at 2 and 9 days after reperfusion. The MO regions by both methods were quantified as percent left ventricular (% LV) mass. Radioactive microspheres were injected for blood flow determination. Postmortem, the myocardium was stained with thioflavin-S and 2,3,5-triphenyltetrazolium chloride.

RESULTS

Expressed as % total LV, MO by MRI matched in size MO by microspheres using a flow threshold of <40% remote (4.96+/-3.52% vs. 5.32+/-3.98%, p=NS). For matched LV cross sections, MO by CE matched in size MO by microspheres using a flow threshold of <60% remote (13.27+/-4.31% vs. 13.5+/-4.94%, p=NS). Both noninvasive techniques correlated well with microspheres (MRI vs. CE, r=0.87 vs. 0.74; p=NS). Microvascular obstruction by CE corresponded spatially to MRI-hypoenhanced regions and thioflavin-negative regions. For matched LV slices at 9 days after reperfusion, MO measured 12.94+/-4.51% by CE, 7.11+/-3.68% by MRI and 9.18+/-4.32% by thioflavin-S. Compared to thioflavin-S, both noninvasive techniques correlated well (CE vs. MRI, r=0.79 vs. 0.91; p=NS). Microvascular obstruction size was unchanged at 2 and 9 days (CE: 13.23+/-4.11% vs. 12.69+/-4.97%; MRI: 5.53+/-4.94% vs. 4.68+/-3.44%; p=NS for both).

CONCLUSIONS

Both CE and MRI can quantify MO. Both correlate well with the histopathologic standards. While MRI can detect regions of MO with blood flow <40% of remote, the threshold for MO by CE is <60% remote. The extent of MO is unchanged at 2 and 9 days after reperfusion.

DNA short tandem repeat profiling of Chinese population in Taiwan determined by using an automated sequencer

We performed a population study on a Taiwan population using a set of nine short tandem repeat (STR) loci and the amelogenin locus. Allele and genotype frequencies of the STR systems D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820 were determined by polymerase chain reaction followed by automated sequencer analysis. A total of 80 alleles could be observed, using all systems, in a population of 500 individuals. No new intermediate fragments were found in these systems. Allele frequencies showed no deviation from the Hardy-Weinberg equilibrium. The mean exclusion power (MEP) ranged from 0.294 for TPOX to 0.711 for FGA (the combined MEP was > 0.999), the discriminating power (DP) ranged from 0.782 for TPOX to 0.964 for FGA, (the combined DP was > 0.99999999949).

Prognostic significance of microvascular obstruction by magnetic resonance imaging in patients with acute myocardial infarction

BACKGROUND

The extent of microvascular obstruction during acute coronary occlusion may determine the eventual magnitude of myocardial damage and thus, patient prognosis after infarction. By contrast-enhanced MRI, regions of profound microvascular obstruction at the infarct core are hypoenhanced and correspond to greater myocardial damage acutely. We investigated whether profound microvascular obstruction after infarction predicts 2-year cardiovascular morbidity and mortality.

METHODS AND RESULTS

Forty-four patients underwent MRI 10 +/- 6 days after infarction. Microvascular obstruction was defined as hypoenhancement seen 1 to 2 minutes after contrast injection. Infarct size was assessed as percent left ventricular mass hyperenhanced 5 to 10 minutes after contrast. Patients were followed clinically for 16 +/- 5 months. Seventeen patients returned 6 months after infarction for repeat MRI. Patients with microvascular obstruction (n = 11) had more cardiovascular events than those without (45% versus 9%; P=.016). In fact, microvascular status predicted occurrence of cardiovascular complications (chi2 = 6.46, P<.01). The risk of adverse events increased with infarct extent (30%, 43%, and 71% for small [n = 10], midsized [n = 14], and large [n = 14] infarcts, P<.05). Even after infarct size was controlled for, the presence of microvascular obstruction remained a prognostic marker of postinfarction complications (chi2 = 5.17, P<.05). Among those returning for follow-up imaging, the presence of microvascular obstruction was associated with fibrous scar formation (chi2 = 10.0, P<.01) and left ventricular remodeling (P<.05).

CONCLUSIONS

After infarction, MRI-determined microvascular obstruction predicts more frequent cardiovascular complications. In addition, infarct size determined by MRI also relates directly to long-term prognosis in patients with acute myocardial infarction. Moreover, microvascular status remains a strong prognostic marker even after control for infarct size.

Evoked facial nerve EMG and brainstem auditory evoked potential monitoring in cerebellopontine angle tumor resection

BACKGROUND

The preservation of normal nerve function or identification of nerve route is critical in some surgeries of cerebellopontine angle tumors. Over the last 5 years, intraoperative facial nerve electromyogram (EMG) and brainstem auditory evoked potential (BAEP) were applied for evaluation of facial nerve integrity and brainstem function in patients while undergoing resection of cerebellopontine angle (CPA) tumor. This report represents the retrospective analysis of our results.

METHODS

The inhalational anesthesia with 1-1.5% isoflurane in pure O2 was used. Muscle relaxation was maintained with continuous infusion of atracurium. The degree of muscle relaxation was aimed at a T4/T1 ratio of train-of-four response more than 20% of the adductus pollicis upon ulnar nerve stimulation at the wrist. In 236 patients suffering from CPA tumor without facial palsy, the EMG of the mentalis muscle ipisilateral to the tumor was obtained through stimulation of the facial nerve. The stimulation was applied with a nerve finder, which delivered an electrical stimulation of a single 2 mamp direct current. The EMG finding was compared with the clinical result. In 198 patients, BAEP was used to monitor the brainstem function during tumor resection. In case of intact hearing the BAEP was taken ipsilateral to the operation side and in case with total hearing loss contralateral BAEP to operation side was used. For BAEP stimulation, 90 db click sound stimulation with frequency of 11.26 Hz was applied to both ears. BAEP signals were obtained and recorded at the mastoid region of either side in reference to the vertex. The EMG and BAEP signals were recorded and saved to an evoked potential monitor.

RESULTS

In facial nerve EMG monitoring, there were two false positive and no false negative tests. Except for the two false positive tests, the postoperative clinical results in the other cases were compatible with the intraoperative facial nerve EMG findings. In BAEP monitoring, there were twenty-eight positive tests.

CONCLUSIONS

The low incidence of false negative test suggests that facial nerve EMG is valuable in detection of facial nerve function in CPA tumor resection. Intraoperative BAEP abnormality is possibly useful in identifying postoperative brainstem dysfunction.

Dislodgment of catheter during arterial cannulation: a case report

Invasive blood pressure monitoring is important in medical practice, especially for hemodynamic monitoring of the critically ill. Catheter dislodgment is a rarely reported complication. We herein report a catheter dislodgment complication during the procedure of arterial cannulation.

Comparative effects of thiopentone and propofol on respiratory resistance after tracheal intubation

To compare the effects of propofol and thiopentone on tracheal intubation-induced bronchoconstriction, 37 patients were allocated randomly to anaesthesia with either thiopentone 4 mg kg-1 followed by a 15-mg kg-1 h-1 continuous infusion or propofol 3 mg kg-1 followed by a 9-mg kg-1 h-1 continuous infusion. Intubation was facilitated by vecuronium 0.1-0.2 mg kg-1. Respiratory system resistance (Rrs) was measured by a CP-100 pulmonary function monitor, 5 min after intubation. The 5-min post-intubation Rrs values were significantly lower in the propofol group (8.5 (SD 1.5) cm H2O litre-1 S-1) than in the thiopentone group (10.9 (3.2) cm H2O litre-1 S-1). Thirty minutes after commencing isoflurane-nitrous oxide anaesthesia, Rrs declined by 17.5 (SEM 3.6)% from baseline in the thiopentone group, but by only 1.6 (2.6)% in the propofol group. We conclude that the dose of propofol administered provided more protection against tracheal intubation-induced bronchoconstriction than an induction dose of thiopentone.

Isoflurane anesthesia does not add to the bronchodilating effect of a beta 2-adrenergic agonist after tracheal intubation

This double-blind study investigates whether isoflurane/N2O anesthesia adds to the bronchodilating effect of the beta 2-adrenergic agonist, fenoterol, after an endotracheal tube (ETT)-induced increase in airway resistance. Forty-five patients with ASA physical status I-II were randomly assigned to two groups: fenoterol-treated patients (n = 23) were given three metered-dose inhaler puffs (600 micrograms) of fenoterol 10 min before induction of anesthesia and placebo-treated patients (n = 22) received three puffs of an aerosol containing no medication. Anesthesia was induced with thiopental and vecuronium intravenously. Respiratory system resistance (Rrs) was measured using a CP-100 pulmonary function monitor 5 min after endotracheal intubation. Inhalation anesthesia was then begun using 50% N2O in O2 with end-tidal 1.3% isoflurane. Rrs measurements were repeated at 5, 15, and 30 min after the initiation of inhalation anesthesia. Postintubation Rrs was significantly lower in the fenoterol-treated patients than in the placebo-treated patients. Rrs declined by a mean of 17.1% after 30 min of inhalation anesthesia in the placebo-treated patients but declined by only 1.4% in the fenoterol-treated patients (P < 0.05 for fenoterol provides protection versus placebo). Our results confirm that fenoterol provides protection against ETT-induced increase of airway resistance. However, isoflurane, while a potent bronchodilator, does not add to the effect of fenoterol.

Silicone intubation with tissue glue anastomosis in the treatment of congenital nasolacrimal duct obstruction

BACKGROUND AND OBJECTIVE

To evaluate the advantages of tissue glue application for the anastomosis of silicone intubation in congenital nasolacrimal duct obstruction.

PATIENTS AND METHODS

Patients with congenital nasolacrimal duct obstruction were treated with silicone intubation with the aid of tissue glue for end-to-end anastomosis. The recurrence rate, complications, and the need for general anesthesia at tube removal were recorded.

RESULTS

The silicone tubes for all 18 eyes studied were removed smoothly on an outpatient basis. Early extrusion was noted in 3 eyes. No recurrence of epiphora was noted in any eye after more than 6 months of follow-up.

CONCLUSION

Tissue glue anastomosis is a beneficial modification that avoids the need for general anesthesia during stent removal in children and allows removal to be easily performed in an outpatient clinic.

Inhaled fenoterol pretreatment attenuates airway resistance response to endotracheal intubation

BACKGROUND

Endotracheal intubation may induce vagal mediated bronchoconstriction. As fenoterol possesses bronchodilation effects, we studied the efficacy of fenoterol pretreatment on the increased resistance of total respiratory system (Rrs) caused by reflex bronchoconstriction in endotracheal intubation.

METHODS

Fifty patients were randomly allocated into two groups; group A (n = 25) with fenoterol inhaled and group B (n = 25) with placebo inhaled 10 min before induction. Patients were induced with sodium thiopental and vecuronium and resistance was measured 2 and 5 min after intubation with a Bicore pulmonary function monitor. Suctioning of the airway was performed 1 min before each measurement. Patients were further categorized into four conditions by smoking history and the presence of sputum in the suctionings. Condition I included patients that were smokers with no sputum collected. Condition II had non-smokers with no sputum collected. Condition III had patients with sputum collected but with no smoking history and condition IV were patients who had sputum collected and had a smoking history.

RESULTS

Patient who received fenoterol have significant lower total respiratory after intubation than those receiving placebo. There were no significant differences in post-intubation Rrs between smokers and non-smokers. Patients with sputum had the highest resistance after intubation with the placebo group. Heart rate and blood pressure were augmented in both groups.

CONCLUSIONS

Fenoterol pretreatment produced lower post-intubation Rrs after intubation when compared with the placebo group suggesting of a protective effect in vagal mediated bronchoconstriction.

[Squamous cell carcinoma originating from ovarian dermoid cyst--report of three cases]

We report three cases of squamous cell carcinoma originating from ovarian dermoid cysts. All patients were postmenopausal with the chief complaints of lower abdominal pain and palpable masses found by themselves. Two of them had diabetes mellitus. The tumor sizes were all more than 10 cm. The diagnoses were made by histological examination of tissues removed at surgery. Two cases were categorized into the FIGO stage IIIc and one in stage Ia. Sonographic findings were characterized by a large adnexal mass with mixed components. An elevated serum squamous cell carcinoma antigen was found in the two cases of advanced stage and one of them also had an elevated serum CA-125 level. All reported cases were unilaterally involved without ascites at laparotomy, while omental lymph nodes metastases were noted in the two cases of advanced stage. One of the patients in the advanced stage died six months after surgery and radiation therapy due to recurrence. The other patient in the advanced stage refused further treatment even though recurrence was found five months after surgery and chemotherapy. There was no evidence of recurrence in the early stage case during the two years of follow-up.

Endotracheal lidocaine instillation in pediatric anesthesia

The purpose of this study is to evaluate the effectiveness of lidocaine administered via the endotracheal tube in suppressing cough reflex during anesthetic recovery in children. Fifty ASA class I-II children, aged from 1-5 years old undergoing elective abdominal or urogenital surgery were randomly assigned into two groups. 2% lidocaine 1.5 mg/kg (1ml = 20mg) was administered in group B while normal saline (N/S) 0.1 ml/kg was used in group A (control group). Either one of the agents was instilled into the endotracheal tube right before the end of operation. Airway responses and other associated phenomena were recorded during the recovery period. Recovery condition was categorized into a two-grade categories, namely "good", and "poor" to denote the quality of recovery. Recovery conditions differ significantly between the control group and the experimental group. In group A, 3 patients were classified as the "good" grade but 22 patients were categorized in the "poor" grade. Group B (lidocaine 1.5 mg/kg) has a much better recovery condition than the control group, there were 19 in the "good" grade and only 6 in the "poor" grade. The experimental group treated with 2% lidocaine presented a significantly better recovery than the control group. This effective suppression of the cough reflex might be due to the local anesthetic effect exerted by lidocaine. For the sake of safety all patients were closely followed up at the post anesthesia room until the return of consciousness and laryngeal reflexes. In conclusion, we found that 2% lidocaine 1.5 mg/kg given intratracheally via the endotracheal tube could attenuate cough response during recovery in pediatric anesthesia.

Hypervolemic therapy prevents volume contraction but not hyponatremia following subarachnoid hemorrhage

Hyponatremia is common following subarachnoid hemorrhage and has alternatively been attributed to either the inappropriate secretion of antidiuretic hormone or natriuresis causing intravascular volume contraction. We prospectively studied body sodium and intravascular volume regulation in 19 patients, beginning within 3 days after acute aneurysmal subarachnoid hemorrhage occurred, in order to determine the impact of hypervolemic therapy on both hyponatremia and volume contraction and to ascertain whether humoral factors account for hyponatremia. Serial measurements of plasma arginine vasopressin, atrial natriuretic factor, renin activity, aldosterone, and catecholamines were correlated with body sodium and fluid balance, change in blood volume, serum sodium concentration, and osmolality. Six patients (32%) developed hyponatremia, but only 2 had a negative sodium balance. In most patients, levels of atrial natriuretic factor were elevated, while plasma renin activity and aldosterone concentrations were generally suppressed. Plasma arginine vasopressin levels were not suppressed during hypo-osmolality and did not correlate with serum osmolality in hyponatremic patients. Only 1 patient had a decrease in blood volume, which was associated with marked rises in aldosterone and plasma renin activity, but normal serum sodium and plasma atrial natriuretic factor levels. We conclude that following subarachnoid hemorrhage: (1) Hypervolemic therapy prevents volume contraction but not hyponatremia, (2) humoral factors may favor both sodium loss and water retention, and (3) arginine vasopressin regulation is disturbed and may contribute to hyponatremia.

Mechanisms regulating neurohypophysial blood flow and function during isotonic volume expansion

Regional cerebral and neurohypophysial blood flow responses to isotonic extracellular fluid volume expansion were studied in pentobarbital-anesthetized dogs using radiolabeled microspheres. Measurements were made at baseline and after increasing pulmonary capillary wedge pressure by 8 +/- 2 mmHg. Plasma arginine vasopressin (AVP) decreased by 50%, and neural lobe blood flow (NLBF) decreased by 47%. Blood flow through median eminence and other brain regions was unchanged. We investigated potential mechanisms responsible for the NLBF changes. Following control vagotomy, AVP concentration increased during the first hour and then returned to control values for hours 2 and 3, whereas NLBF was unchanged for the first hour and fell after 2 and 3 h. Vagus section abolished the decrease in NLBF but not the AVP response to volume expansion. The contribution of left atrial and pulmonary baroreceptors to this response was tested by inflation of a balloon in the left atria to produce a 13 +/- 1 mmHg rise in atrial pressure. This led to a 20% reduction in NLBF, a 35% reduction in AVP concentration, and a 270% increase in plasma atrial natriuretic factor (ANF). However, ANF release does not account for the NLBF changes, since intravenous ANF infusion had no effect on NLBF or AVP concentration. These data suggest that the NLBF response to volume expansion is mediated by the vagus with input from multiple cardiopulmonary baroreceptors.

Two-color immunofluorescence and flow cytometric analysis of lamina propria lymphocyte subsets in ulcerative colitis and Crohn's disease

By using two-color immunofluorescence with fluorescein isothiocyanate (FITC) and phycoerythrin (PE)-labelled monoclonal antibodies and multiparameter flow cytometry, we investigated lamina propria lymphocyte subsets of patients with ulcerative colitis (UC) and Crohn's disease (CD). Leu-3/Leu-2 (CD4/CD8) ratio of lamina propria lymphocytes (LPL) of CD (mean +/- SD: 1.9 +/- 0.8, P less than 0.01) was significantly decreased compared with controls (3.3 +/- 1.1), because of an increased number of CD8+ lymphocytes. The majority of lamina propria CD4+ cells were CD4+, Leu-8- and CD4+, CD45R- both in controls and IBD tissue. Many lamina propria T lymphocytes were activated, expressing HLA-DR antigen not only in IBD but also in controls. NK cells defined by CD16 and CD 56 (3.0 +/- 1.4%, P less than 0.01) were significantly decreased in patients with UC compared with controls (6.5 +/- 3.0%). A low proportion of B cells in the intestinal mucosa expressed Leu-8 antigen and CD23 antigen. The proportion of activated B cells of LPL was high in IBD mucosa as well as normal mucosa. These findings suggest that local activation of B cells leads to the loss of the expression of Leu-8 antigen and CD23.