Improved translational efficiency of subtilisin YaB gene with different initiation codons in Bacillus subtilis and alkalophilic Bacillus YaB

The ale gene specifying the subtilisin YaB produced by alkalophilic Bacillus YaB, has an unusual start codon UUG. Changing this codon to AUG and GUG increased expression of the ale gene in B. subtilis DB104 and in an ale deficient mutant strain YaB-DEC4. The relative translational efficiency order of the three initiation codons is AUG > GUG > UUG in B. subtilis DB104 and in YaB-DEC4. These data suggest that the preferred initiation codon is AUG for ale gene expression in Bacillus.

The efficacy of intrathecal coadministration of morphine and bupivacaine for labor analgesia

BACKGROUND

Intrathecal (i.t.) opioids can provide labor analgesia, but the onset of pain relief is slow. Bupivacaine has the beneficial property of less motor blockade than other local anesthetics. This study retrospectively examined the efficacy of concomitant use of i.t. morphine and bupivacaine for labor pain relief.

METHODS

Fifty five nulliparas who requested analgesia in the active phase (IA group) prior to a cervical dilation 3.9 +/- 0.6 cm and received i.t. morphine 0.5 mg and 0.1% bupivacaine 2.5 mg served as the treatment group, and 88 similar nulliparas who did not request and receive analgesia served as the control group.

RESULTS

The mean onset time of analgesia was 2.6 +/- 0.5 min, the duration was 4-12 h and 93% of parturients did not request additional analgesia after a single injection of i.t. morphine and bupivacaine. The active phase of the first and second stages of labor in the treatment group were significantly longer [318 +/- 214 min vs. 176 +/- 120 min; 74 +/- 29 min vs. 37 +/- 26 min]. Frequency of instrument-assisted vaginal delivery was higher compared with the control group (30.9% vs. 14.1%). However, there were no significant differences in the rate of cesarean section and the Apgar scores of newborns at 1 min and 5 min between the treatment and control group. The major side effects of the treatment group included pruritus (48%), nausea (40%), vomiting (37%), somnolence (27%), shivering (27%), urinary retention (21%), hypotension (15%), and bradycardia (13%). Most of the side effects were mild and could be alleviated by naloxone. Neither post-spinal headache nor respiratory depression was noted.

CONCLUSIONS

Our results showed that a single injection of i.t. morphine and bupivacaine provided rapid onset and effective analgesia with manageable side effects and without major complications. Thus, i.t. morphine and bupivacaine provides an alternative to epidural analgesia for most women in labor.

NitroG-L-arginine methyl ester reduces the minimal alveolar concentration of isoflurane in rabbits

BACKGROUND

Recently, some studies suggested that nitric oxide (NO) plays a role as a mediator in the central nociceptive pathways and is possibly involved the mechanisms of anesthesia and wakefulness. Inhibition of the L-arginine-NO pathway in the central nervous system may result in an anesthetic, analgesic, or sedative effect. The aim of the present study was to evaluate the effects of the nitric oxide synthase inhibitor (NOSI), nitroG-L-arginine methyl ester (L-NAME), on the threshold for isoflurane anesthesia in rabbits.

METHODS

Sixteen New Zealand rabbits were randomly divided into two groups, with eight rabbits in each group. In the study group, a dose of L-NAME 30 mg/kg was injected i.v. daily as pretreatment on three consecutive days, and the fourth dose of L-NAME was given 30 min before the study began. Normal saline was given to the control group. Data of minimal alveolar concentration (MAC), blood pressure (BP), and heart rate (HR) were collected from both groups. Vital signs, such as EtCO2, O2 saturation, and temperature, were maintained within the normal range. All data were described as mean +/- SEM. Statistical analysis was performed using Student's t-test, where p < 0.05 was considered significant.

RESULTS

MAC of isoflurane in the control group was 1.90 +/- 0.12%. MAC of the L-NAME group was 1.70 +/- 0.22%, significantly lower than the control group (p < 0.05).

CONCLUSIONS

Our preliminary result shows that the MAC of isoflurane in animals treated with L-NAME was lower than that in the control group. It is suggested that inhibition of the nitric oxide pathway may enhance the effect of isoflurane.

Spectral analysis of a thalamus-to-cortex seizure pathway

Physiological evidence has shown that the anterior thalamus (AN) and its associated efferents/afferents constitute an important propagation pathway for one animal model of generalized tonic-clonic epileptic seizures. In this study we extend and confirm the support for AN's role by examining neuroelectric signal indicators during seizure episodes. We show that the electroencephalogram (EEG) recorded from AN is highly coherent with the EEG derived from the cortex (CTX). By removing the effects of another thalamic nucleus, posterior thalamus (PT)-unaffiliated with the tract linking AN to cortex-partial coherence analysis leaves the CTX/AN coherence undiminished. The most robust band of strong CTX-AN coherence is centered around the spike-wave pacing frequency of 1-3 Hz. Partial-multiple coherence analysis techniques are used to remove the possible signal contribution from hippocampus in addition to PT. The CTX-AN coherence still remains undiminished in the low-frequency bands. Conclusive evidence from coherence studies and other spectral measures reaffirm the special role of the AN in the propagation of seizure activity from subcortex to cortex.

Enhanced deoxyribonucleic acid damage and repair but unchanged apoptosis in uterine leiomyomas treated with gonadotropin-releasing hormone agonist

OBJECTIVE

Our purpose was to investigate the histopathologic changes in uterine leiomyomas in cell proliferation, proliferating cell nuclear antigen expression, angiogenesis, and apoptosis after treatment with gonadotropin-releasing hormone agonist.

STUDY DESIGN

Fifteen consecutive patients who had undergone gonadotropin-releasing hormone agonist treatment before surgery and 44 patients who did not were studied. The volumes of myomas were determined ultrasonographically, and in patients receiving gonadotropin-releasing hormone agonist therapy measurements were done again after administration of the gonadotropin-releasing hormone agonist to evaluate the response to treatment. Paraffin sections were stained with hematoxylin and eosin, PC 10 for proliferating cell nuclear antigen expression, MIB 1 for measurement of cell proliferation, ApopTag for apoptosis, and factor VIII for quantitation of microvessel density. A deoxyribonucleic acid fragmentation test was also done on nine cases with available frozen tissues.

RESULTS

Most of the leiomyomas showed substantial expression of proliferating cell nuclear antigen. Gonadotropin-releasing hormone agonist therapy further induced significant overexpression of proliferating cell nuclear antigen (p = 0.0004, chi 2 test). All three leiomyomas that failed to respond to therapy showed less proliferating cell nuclear antigen staining compared with the good responders. In contrast, data from MIB 1 immunostaining showed that < 0.3% of leiomyoma cells were proliferating. However, positive-staining cells were more frequently detected in the treatment group (0.075% +/- 0.091% vs 0.002% +/- 0.010%, p = 0.0002, Mann-Whitney U test). Apoptosis developed spontaneously in leiomyoma cells independent of gonadotropin-releasing hormone agonist therapy. No significant change in apoptosis but a significant increase in microvessel density was observed in the treatment group compared with the control group.

CONCLUSION

Enhanced deoxyribonucleic acid damage or repair with cell growth arrest may be responsible for the action of gonadotropin-releasing hormone agonist in shrinking uterine leiomyomas. Moreover, the extent of proliferating cell nuclear antigen expression seems to be associated with the response to gonadotropin-releasing hormone agonist therapy.

DAP-kinase loss of expression in various carcinoma and B-cell lymphoma cell lines: possible implications for role as tumor suppressor gene

DAP-kinase is a novel calmodulin dependent serine/threonine kinase that carries ankyrin repeats and the death domain. It was recently isolated, by a functional selection approach of gene cloning, as a positive mediator of programmed cell death. In this study the expression of DAP-kinase was examined in the cell lines derived from various human neoplasms. DAP-kinase mRNA and protein expression were below the limit of detection in eight out of ten neoplastic derived B-cell lines. In six out of 14 examined bladder carcinoma, in three out of five renal cell carcinoma, and in four out of ten tested breast carcinoma cell lines, the DAP-kinase protein levels were below detection limits or lower than 1% compared to the positive cell lines. Interestingly, DAP-kinase expression could be restored in some of the negative bladder carcinoma and B-cell lines by treatment of cells with 5'-azadeoxycytidine that causes DNA demethylation. The high frequency of loss of DAP-kinase expression in human tumor cell lines, and the occasional involvement of methylation in this process raise the possibility that this novel mediator of cell death may function as a tumor suppressor gene.

Uterine leiomyosarcoma has deregulated cell proliferation, but not increased microvessel density compared with uterine leiomyoma

OBJECTIVE

To investigate the differences of biological aggressiveness in terms of proliferating cell nuclear antigen (PCNA) expression, cell proliferation, and microvessel density between uterine leiomyosarcoma and leiomyoma.

STUDY DESIGN

All patients with uterine leiomyosarcoma undergoing surgery at National Cheng Kung University Hospital were eligible. Forty-four patients with uterine myoma were also studied as the benign counterpart. The paraffin-embedded slides were stained with hematoxylin and eosin to confirm the presence of tumor and to quantitate mitoses, PC 10 for measurement of PCNA expression, MIB 1 for measurement of cell proliferation, and factor VIII for quantitation of microvessel density. The immunohistochemical findings of the slides were correlated with clinocopathologic findings of the patients, and the data were analyzed by either chi2 or unpaired t test.

RESULTS

Six patients with uterine leiomyosarcoma and 44 patients with uterine leiomyoma were studied. Statistically significant higher mean levels of PCNA and MIB 1 were observed in uterine leiomyosarcoma compared with those of uterine myoma (for PCNA expression, P = 0.0001; for MIB 1, 11.61 +/- 11.42% vs 0.45 +/- 0.21%, P < 0.0001). No significant difference of microvessel density was observed between these two groups (65.73 +/- 48.62 vs 41.97 +/- 28.20, P = 0.084). Among the six patients with leiomyosarcoma, two patients with a higher percentage of MIB 1-positive tumor cells died of recurrent disease. In contrast, two patients with lower MIB 1 counts were disease-free for 3 years or more.

CONCLUSION

Deregulated cell growth in uterine leiomyosarcoma may account for the biological aggressiveness of this tumor. Furthermore, the percentage of MIB 1-positive tumor cells seems to be associated with the prognosis or extent of uterine leiomyosarcoma.

Subsequent reproduction and obstetric outcome after methotrexate treatment of cervical pregnancy: a review of original literature and international collaborative follow-up

The case reports of 22 patients with cervical pregnancies treated by methotrexate (MTX) administration and published in English literature between 1983 and 1995 were reviewed, by either original paper review or follow-up under international collaboration, to determine the subsequent reproductive performance and obstetric outcomes. Out of 22 cases, 18 (78%) MTX chemotherapy attempts succeeded with complete remission and four (22%) failed. Of the 13 women who wished to conceive and could be followed for at least 3 years, nine succeeded in having live births without congenital malformations, one spontaneously aborted and three suffered infertility. In general, MTX chemotherapy alone or combined with adjuvant methods such as subsequent cervical curettage or cervical tamponade, or intracervical potassium chloride injection, appears to be a convenient and effective method for the treatment of the majority of cervical pregnancies before 12 weeks gestation, and has not been shown to have detrimental effects on subsequent reproductive capacities, obstetric outcomes and progeny health for those cases with successful preservation of the uteri.

Acquired tracheomalacia--a case report

Tracheomalacia is a condition characterized by weakness of the tracheal walls and supporting cartilage. It may be congenital, occurring in association with other lesions, such as vascular ring, tracheoesophageal fistula, dyschondroplasia, congenital cysts or tumors, or it may be acquired, most commonly as a result of protracted endotracheal intubation and less often of irradiation, trauma or neoplasm. We present a case of acquired tracheomalacia in a 15-year-old boy, a victim of Proteus syndrome (hemihypertrophy, subcutaneous tumors, and macrodactyly), who had congenital scoliosis with secondary chronic restrictive pulmonary disease, for which he was admitted to our hospital for surgical correction of the spine. Unfortunately, his conditions, particularly of respiratory, worsened after the operation, which called for an emergent tracheostomy. During the procedure, high airway pressure and CO2 retention developed, and an extreme narrowing of the tracheal lumen was revealed by fiberoptic bronchoscopy. Acquired tracheomalacia was diagnosed. The probable mechanisms, diagnostic tests, and treatments of tracheomalacia are hereunder discussed.

Evidence for two tumor suppressor loci associated with proximal chromosome 9p to q and distal chromosome 9q in bladder cancer and the initial screening for GAS1 and PTC mutations

The most common genetic alteration identified to date in bladder cancer is loss of heterozygosity (LOH) of chromosome 9, suggesting the presence of possible tumor suppressor genes on this chromosome. We attempted to map the location of these genes by analyzing 69 primary transitional cell carcinomas of the bladder with a panel of microsatellite markers for LOH on chromosome 9. Monosomy 9 (defined by LOH of all informative markers analyzed on 9p and 9q) was detected in 26 of 69 (38%) tumors, and 22 of 69 (32%) tumors showed subchromosomal deletions. Twelve tumors (17%) demonstrated partial LOH of chromosome 9 and indicated two distinct regions of LOH. Eight tumors showed distal allelic loss of 9q with a minimal region of common deletion flanked proximally by marker GSN on 9q33. Six tumors showed proximal allelic loss of 9p and 9q with a minimal area of common deletion flanked by markers D9S970 on 9p12 and D9S283 on 9q21. Two tumors showed loss of both the distal region of 9q and the proximal region of 9p and 9q, which were separated by a possible 6-44 cM of retained genetic material. The proximal minimal area of common deletion excluded 9q22.3-q31 to where two putative tumor suppressor genes, the nevoid basal cell carcinoma syndrome and multiple self-healing squamous epithelioma (ESS1) genes, have been mapped. The growth arrest-specific gene (GAS1), a candidate tumor suppressor gene, was included within the proximal minimal region. We evaluated the GAS1 gene for its potential role in bladder cancer using single-strand conformational polymorphism to screen for mutations in GAS1 in 10 bladder cancer cell lines and 14 primary bladder tumors. A polymorphism at codon 88 was noted in one primary bladder tumor, but no other abnormalities were found, suggesting that another potential tumor suppressor gene important to bladder cancer resides in these minimally deleted regions. Because the nevoid basal cell carcinoma syndrome gene has long been speculated to be a putative tumor suppressor gene in bladder cancer and this gene has recently been characterized as the human homologue of the Drosophila patched gene (PTC), 20 primary bladder tumors with chromosome 9q LOH were screened for mutations in PTC using single-strand conformational polymorphism and heteroduplex analysis. No alterations were found in any of the samples analyzed. Furthermore, 4 of 37 noninvasive papillary (Ta) tumors demonstrated loss of all 9q markers with retention of 9p, whereas no Ta tumor showed loss of 9p with retention of all 9q markers, suggesting that LOH of 9q is the earlier event in bladder tumorigenesis. In summary, our results indicate two tumor suppressor loci associated with proximal chromosome 9p to q and distal chromosome 9q that may be important in bladder cancer. GAS1 and PTC do not seem to be frequently mutated in bladder cancer.

Restriction of substrate specificity of subtilisin E by introduction of a side chain into a conserved glycine residue

Substitution of the conserved Gly127 for residues having a side chain markedly changed the substrate specificity of subtilisin E from Bacillus subtilis. The crystallographic findings suggested that Gly127 is responsible for accepting even the large P1 substrates, and the marked change of specificity was attributed to the introduction of a side chain in this position. To test this hypothesis, Gly127 was replaced with 3 non-charged amino acids, Ala, Ser and Val. When assayed with synthetic peptide substrates, all mutants purified from the periplasmic space in Escherichia coli showed a marked preference for small P1 substrate up to 150-fold relative to the wild-type. The kinetic data and molecular modeling analysis suggest that large hydrophobic P1 residues were unable to access the binding pocket due to steric hindrance.

Multivariate analyses of the relationship between umbilical cord length and obstetric outcome

To investigate the clinical significance of umbilical cord length in human pregnancies, 1087 deliveries at Kaohsiung Chang Gung Memorial Hospital from May 1995 to August 1995 were studied. Our data showed that male fetuses had longer cord length than female and vertex presentation had longer cord length than breech presentation. The cord length and placental weight were significantly related to the birth weight. We found that: 1) only intrauterine growth retardation was associated with the increased risk of fetal distress; 2) secondary arrest of labor and advanced gestational age were correlated with meconium stain; and 3) birth weight and presence of meconium stain were correlated with the secondary arrest (p < 0.05). However, there was no significant correlation between umbilical cord length and fetal well-being. As a result of multivariate analyses, we conclude that the umbilical cord length does not significantly correlate with either maternal age, gestational age (> or = 28 weeks), parity fetal outcome or intrauterine fetal well-being. Birth weight is the only characteristic that is correlated with cord length.

Shortening and superlon-wrapping the downstream tube can increase the useful range of the blood warmer

BACKGROUND

Hypothermia occurs frequently in clinical anesthesia. Many apparatus were introduced to keep intravenous fluid warm. But at low to medium flow rates little effects have been achieved because of heat lost along the tube. Superlon, an industrial heat-preserving material widely used in air conditioning to prevent temperature change, has never been used in the blood warmer.

METHODS

The study was performed in three groups group I using standard (120 cm) unwrapped tube (Animac AM-4 set), group II using a shortened downstream tube (60 cm), and group III using the downstream tube which was further wrapped with superlon (Super LTD). The blood warmer used was identical in all 3 groups. We recorded the fluid temperatures at different points downstream at various flow rates. The values were then compared among groups.

RESULTS

The fluid temperatures before entering the warmer were around 20 degrees C and 37 degrees C at the 2 cm post-warmer points at various flow rates. The end point temperatures rose with flow rates and were the highest in group III and lowest in group I at each flow rate (p < 0.01). In group III the temperature could be kept above 32 degrees C at a very low flow rate (150 ml/h) and above 35 degrees C at 300 ml/h. In group I, 1,000 to 2,000 ml/h were needed to keep the same temperature.

CONCLUSIONS

These refinements increase the useful range of the Animac AM-4 warmer and make it useful in pediatric rapid fluid resuscitation and current fluid management. Moreover, they are easy to set up, inexpensive, and can be applied to any kind of blood warmers.

Relationship of uterine perfusion to outcome of intrauterine insemination

This prospective study was undertaken to evaluate the prognostic value of uterine perfusion on the day of human chorionic gonadotropin administration in patients who were undergoing intrauterine insemination. Uterine perfusion was evaluated by measuring the pulsatility index of the ascending branch of the uterine arteries on the day of administration of human chorionic gonadotropin. No pregnancy occurred when the pulsatility index of the ascending branch of the uterine arteries was more than 3. The fecundity rate was 18% when the pulsatility index was less than 2 and was 19.8% when the pulsatility index was between 2 and 3 (not significant). The continuing pregnancy rate was 18% when the pulsatility index was less than 2, compared with 12.1% when the pulsatility index was between 2 and 3 (P < 0.05). Our data suggest that the measurement of uterine perfusion on the day of human chorionic gonadotropin administration may have predictive value regarding fecundity and the continuation of pregnancy in intrauterine insemination.

Modification of mitomycin C-induced clastogenicity by Terminalia catappa L. in vitro and in vivo

The water extract of the leaves of Terminalia catappa L. was tested for inhibition of mitomycin C-induced micronuclei in CHO-K1 cells. The simultaneous and pre-treatment of CHO-K1 cells with T. catappa extract (75 and 150 micrograms/ml) significantly (P < 0.05) suppressed mitomycin C-induced micronuclei. Furthermore, gastric intubation of T. catappa extract (4.8 and 24 mg/animal per day) to male ICR mice for 8 days significantly (P < 0.01) reduced mitomycin C-induced micronuclei in peripheral blood. In addition, T. catappa dose dependently inhibited lipid peroxidation in vitro and TPA-induced hydrogen peroxide formation in human mononuclear leukocytes. The anticlastogenic effects of T. catappa in vitro and in vivo may be attributed to its antioxidative potential.

[Post-obstructive pulmonary edema following extubation--report of two cases]

Pulmonary edema may develop in healthy patients after anesthesia. It usually results from upper airway obstruction which may be caused by laryngospasm or aspiration. Increased inspiratory effort following airway obstruction significantly produces negative intrathoracic pressure that may lead to pulmonary edema. We reported two cases of post-obstructive pulmonary edema following extubation. They were essentially healthy young males, one of whom received urethroplasty and the other received pulmonary blebectomy. Their hemodynamic and ventilatory conditions had been kept stable during surgery. Upper airway obstruction followed by pulmonary edema developed immediately after extubation, which was successfully treated without any sequelae.

Replantation of ring avulsion of index, long, and ring fingers

The salvage rate of degloved amputation of the fingers is as low as 50%. This case report consists of a multiple-finger degloving amputation characterized by intact tendons, pulleys, and bone, but avulsed neurovascular bundles. After replantation, the range of motion of the fingers was nearly full. Protective-to-light touch sensation was obtained with transpositional digital nerve transfers. Grasp strength was 80% that of the uninjured side. In addition to good functional recovery, the aesthetic appearance obtained by replantation of the degloved skin was far better than that obtained by other reconstruction methods. A first web space flap was used to release a flexion contracture of the proximal interphalangeal joint of the middle finger.

Intratumoral blood flow in uterine myoma correlated with a lower tumor size and volume, but not correlated with cell proliferation or angiogenesis

OBJECTIVE

To investigate the correlation of intratumoral blood flow in uterine myoma with cell proliferation, angiogenesis, tumor size, and tumor volume.

METHODS

Thirty-nine patients who had been scheduled for surgery because of symptomatic uterine myomas were evaluated by transvaginal sonography and color Doppler ultrasound before surgery. The largest dimension of each tumor and the volumes of myomas were determined ultrasonographically. Pulsatility index (PI) was determined by color Doppler ultrasound according to the maximum systolic, end-diastolic, and the mean flow velocities measured within the uterine nodules. After surgery, the paraffin-embedded slides containing representative leiomyoma tissues were stained with hematoxylin and eosin, proliferating cell nuclear antigen for measurement of cell proliferation, and factor VIII for quantitation of microvessel density. The ultrasonographic findings were correlated postoperatively with pathologic findings, and the data were analyzed by simple linear regression and Fisher r to z transformation.

RESULTS

Simple regression analysis of the intratumoral PI values on the sizes of myomas showed a negative correlation (r = -0.47, P = .003; n = 39), whereas a less significant correlation between PI values and tumor volumes was observed (r = -0.42, P = .008). In contrast, no statistically significant correlation was observed between the intratumoral PI values and the values of the proliferating cell nuclear antigen index (r = 0.10, P = .547) or microvessel density counts (r = 0.18, P = .282).

CONCLUSION

The intratumoral blood flow by transvaginal color Doppler ultrasound correlated with a reduced tumor size and tumor volume, but did not correlate with cell proliferation or angiogenesis.

Purification and characterization of a glycerol oxidase from Penicillium sp. TS-622

A novel extracellular glycerol oxidase was purified 39-fold from wheat bran culture of a soil-isolated Penicillium strain TS-622 with an overall yield of 3%. The addition of Triton X-100 into the extraction buffer improved the extraction yield by 90 times, indicating that the enzyme is bound to the cell surface. The molecular weight of this enzyme was 400,000 as determined by size-exclusion high-performance liquid chromatography. The optimum pH was from 6 to 7 and the optimum temperature was 45 degrees C. This enzyme showed high specificity toward dihydroxyacetone and glycerol. It was inhibited by KCN, NaN3, and hydroxylamine.

Clonal analysis of bilateral breast cancer

Forty-nine pairs of bilateral breast tumors (41 synchronous and 8 asynchronous cases) were examined for X-chromosome inactivation status and p53 mutations to address the issue of their clonality. Among 12 cases that were informative for the trinucleotide repeat polymorphism in exon 1 of the androgen receptor gene on the X chromosome, 3 cases were found to have different alleles of the locus inactivated in the right and left breast tumors, indicating that the two tumors arose from distinct transformed cells. Thirteen tumors (13%) from 11 women (22%) contained somatic mutations in exons 5-8 of the p53 gene. In two cases, both breast tumors harbored p53 mutations, but the specific mutations were not identical. Seven synchronous and two asynchronous cases had p53 mutations in one tumor only. A germ line p53 mutation at codon 248, one of the most common p53 mutations in Li-Fraumeni syndrome, was observed in one case. Immunohistochemical analysis of p53 protein with a monoclonal antihuman p53 antibody showed concordant positivity between the right and left tumors in three bilateral breast cancer cases. Our results suggest that at least some bilateral breast tumors originate from distinct cells, but that some bilateral breast tumors may be related through a common p53 abnormality.

A comparison of the effect of halothane on N-methyl-D-aspartate and non-N-methyl-D-aspartate receptor-mediated excitatory synaptic transmission in the hippocampus

Halothane depresses synaptic transmission in the rat brain. First we determined the concentration of halothane which decreased the amplitude of the population spike recorded in the CA1 region of the hippocampus to 50% of the control value (105 +/- 4.9 micrograms/mL [0.53 mM] halothane). Hippocampal glutamate receptors are divided into N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionate (AMPA) and kainate (non-NMDA) subtypes. The NMDA and non-NMDA receptors were blocked with (+/-)-2-amino-5-phosphonopentanoic acid (AP5) (30 microM), and 6,7-dinitroquinoxaline-2,3-dione (DNQX) (10 microM), respectively, to allow observation of the effects of halothane on the NMDA and non-NMDA receptors, respectively. gamma-Aminobutyric acid type A (GABAA) receptors were blocked in all studies with picrotoxin (PTX) (40 microM). When the non-NMDA receptors were blocked a halothane concentration of 38.1 +/- 5.6 mg/mL was required to produce a further 50% decrease in population spike amplitude. When NMDA receptors were blocked with AP5 or only GABAA receptors were blocked the halothane concentrations needed to produce 50% block were higher than needed for the control (160.8 +/- 17.8 and 190.2 +/- 12.1 microgram/mL, respectively). These studies indicate that the NMDA receptors are more sensitive to the effects of halothane than the non-NMDA receptors.

Purification and partial characterization of an alkaline lipase from Pseudomonas pseudoalcaligenes F-111

An extracellular alkaline lipase of alkalophilic Pseudomonas pseudoalcaligenes F-111 was purified to homogeneity. The apparent molecular weight determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 32,000, and the isoelectric point was 7.3. With p-nitrophenyl esters as its substrates, the enzyme shows preference for C12 acyl and C14 acyl groups. It was stable in the pH range of 6 to 10, which coincides with the optimum pH range.

Inhibitory effect of propofol on sympathetic neurotransmission results in changes of plasma neuropeptide Y in rats

1. The effects of propofol on sympathetic neurotransmission and changes of plasma level of neuropeptide Y-like immunoreactivity (NPY-ir) were investigated in rats. 2. Intraperitoneal injection of propofol into rats lowered the systemic blood pressure and plasma NPY-ir in a dose-dependent manner. 3. Decrease of plasma NPY-ir induced by propofol was not modified in adrenalectomized rats. In the activation of adrenergic neurotransmission by a ganglionic nicotinic agonist, elevation of plasma NPY-ir was also reduced by propofol indicating the direct effect on peripheral adrenergic nerve terminals. 4. Plasma level of NPY-ir reversed in parallel with the recovery of anaesthesia induced by propofol. After an intracerebroventricular injection of propofol into the rats, both the lowering of plasma NPY-ir and the induction of anaesthesia were observed. Thus, a central nervous system effect of propofol can also be considered in its effect on plasma NPY-ir. 5. The data suggest that propofol has the ability to lower plasma NPY-ir in rats through an inhibition of adrenergic neurotransmission via central nervous pathway and/or peripheral nerve terminal blockade.

Contiguous patches of normal human mammary epithelium derived from a single stem cell: implications for breast carcinogenesis

Tissue clonality can be assessed in females by analyzing the methylation status of polymorphic DNA markers on X-linked genes because extensive de novo methylation of one allele at the preimplantation stage is associated with its permanent inactivation. We applied X chromosome inactivation toward understanding human breast morphogenesis by examining the nonmalignant breast epithelium from two reduction mammaplasties and a mastectomy. We found that entire lobules and large ducts of normal breast tissue have the same X chromosome inactivated, suggesting that they are derived from the same stem cell. The regions of inactivation of a particular X chromosome do not extend over an entire breast, so that ducts and lobules with opposite chromosomes inactivated are present within a single breast. Potential relevance of these observations for malignant transformation is discussed.

Immunohistochemical detection of Bcl-2 protein in small cell carcinomas

The expression of Bcl-2 protein in 29 small cell carcinomas (SCCs; 6 surgical and 15 biopsy specimens obtained from various organs, 7 metastatic lymph nodes, and 1 metastatic liver tissue) was investigated by immunohistochemical technique. Negative staining was observed in only two cases (7%). The majority of Bcl-2-positive tumors had > 95% positive cells, with a moderate staining intensity. A combined small-cell lung cancer showed discordant staining results between two different histology types. No correlations of Bcl-2 immunoreactivity with p53 expression and clinical staging were found. Our findings suggest that Bcl-2 expression may play a certain role in the early phases of SCC tumorigenesis, or that it may solely be a succeeding property directly derived from the tumor progenitor cells. As the Bcl-2 protein was present in most cases, it is not a useful prognostic or treatment marker for the cancer.

Production and characterization of keratinase of a feather-degrading Bacillus licheniformis PWD-1

The keratinase produced by Bacillus licheniformis PWD-1 was induced by feather powder. Maximal enzyme production could be achieved by culturing in a medium containing 1% hammer-milled feather powder (100 mesh) at 45 degrees C for 30 h. Maximal growth of PWD-1 was achieved at 50 degrees C, and maximal enzyme induction was at 45 degrees C. The molecular mass and isoelectric point of this enzyme were 31.4 kDa and 8.5, respectively. This enzyme was stable from pH 5 to 12. The optimal reaction pHs for feather powder and casein were 8.5 and 10.5 to 11.5, respectively. The optimal reaction temperature was 50 degrees C to 55 degrees C. The relative activity of this enzyme toward casein, feather powder, keratin, elastin, and collagen was 100:52:41:18:7, and 100:56:32:3 for Suc-AAPL-pNA, Suc-AAPF-pNA, Suc-AAPM-pNA, and Suc-AAVA-pNA (Suc, succinyl; pNA, p-nitrophenylanilide).

Predictive value of endometrial sonography in ovulation induction for intrauterine insemination

This prospective study was undertaken to evaluate the prognostic value of the endometrial sonographic pattern on the day of human chorionic gonadotropin (hCG) administration in patients who underwent intrauterine insemination. The endometrial sonographic patterns were classified as homogenous, hyperechogenic (A), intermediate isoechogenic (B) and multiple-layered "triple-line" (C). Type A had no pregnancies, whereas type B had a 20% fecundity rate and type C had a 21.1% fecundity rate. The continuing pregnancy rate was 10% in type B, as compared to 19.3% in type C. The data suggest that the endometrial sonographic pattern on the day of hCG administration may be of predictive value regarding fecundity and continuing pregnancy in the intrauterine insemination cycle.

Cerebral microvascular reactivity to carbon dioxide during isoflurane anesthesia as assessed by laser-Doppler flowmetry

BACKGROUND

To determine the effects of carbon dioxide on the cerebral microcirculation during isoflurane anesthesia.

METHODS

We studied 10 rabbits using laser Doppler flowmetry on the parietal cortex. After surgical preparation, the end-tidal concentration of isoflurane was maintained at one MAC (2.05%). Mean arterial pressure, rectal temperature and hematocrit were kept constant. The arterial carbon dioxide tension (PaCO2) was randomly adjusted to three levels: 20-25 mmHg (hypocapnia); 35-40 mmHg (normocapnia); and 45-50 mmHg (hypercapnia). Cerebral blood flow (CBF) was measured after target PaCO2 had been achieved.

RESULTS

CBF at normocapnia was 27.4 +/- 13.5 (mean +/- SD) ml/100 gm/min, which increased to 42.4 +/- 14.3 ml/100 g/min (p < 0.01) and decreased to 15.3 +/- 7.5 ml/100 g/min (p < 0.05) at hypercapnia and hypocapnia respectively. The slopes of CBF versus PaCO2 were 1.60 +/- 0.63 ml/100 g/min/mmHg from normocapnia to hypercapnia and -0.79 +/- 0.51 ml/100 g/min/mmHg from normocapnia to hypocapnia. The corresponding percentage of alteration in CBF on the respective change of PaCO2 was 7.2 +/- 5.1 and -3.0 +/- 1.2%/mmHg.

CONCLUSIONS

These data indicate that the changes of the cerebral microvascular blood flow reflect the CO2 effects during isoflurane anesthesia.

Mosaicism in human epithelium: macroscopic monoclonal patches cover the urothelium

Previous studies of chimeric animals and human tissues have shown the clonal nature of organ development, giving clues as to the normal development of organs and also to abnormal developments, such as atheromatous plaques. The clonal nature of bladder cancer in female patients has been demonstrated, but little has been known of the clonal development of the normal urothelium. Using an X chromosome inactivation analysis of cells microdissected from histologic slides from the female human bladder, macroscopic urothelial patches of monoclonality were detected. These patches are about 120 mm.2 in size, contain about 2 x 10(6) cells each and reflect the presence of coherent cellular families composed of stem cells and their differentiated derivatives. The large size of these patches was surprising when compared with previously reported patch sizes in other organ systems. The patches most probably are composed of the descendants of the original founder cells, which would suggest that only 200 to 300 cells participated in the formation of the urothelium. The limited number of stem cells, each giving rise to millions of cells may provide an explanation for the "field defect" that is often referred to in the pathogenesis of bladder cancer, as different cell patches may possess different predispositions to tumorigenesis.

Cerebral effects of nitrous oxide during isoflurane-induced hypotension in the pig

We have studied the effects of nitrous oxide on cerebral blood flow (CBF), cerebral blood flow velocity (CBFV) and intracranial pressure (ICP) during isoflurane-induced hypotension in 10 pigs. CBF was measured using laser Doppler flowmetry, CBFV in the right middle cerebral artery was calculated using Doppler ultrasound and ICP was measured using an extradural ICP monitor. Each animal was studied under four conditions, examined sequentially: (i) mean intra-arterial pressure (MAP) 85 mm Hg, maintained with isoflurane, (ii) MAP 50-55 mm Hg, induced by isoflurane only, (iii) MAP 85 mm Hg, maintained with isoflurane and 50% nitrous oxide, and (iv) MAP 50-55 mm Hg, induced by isoflurane and 50% nitrous oxide. No significant differences were noted between conditions with respect to ICP. There was a significant difference in CBF during condition (ii) compared with (i) (mean 75(SD 21) vs 100(0)%) and during condition (iv) compared with (iii) (90(26) vs 109(13)%). Animals under condition (iv) exhibited a 20% reduction in CBFV compared with those under condition (iii) (57 vs 69 cm s-1). For animals under normotensive conditions, addition of nitrous oxide to isoflurane resulted in a 16% increase in CBFV (69 vs 60 cm s-1). Comparing isoflurane-induced hypotension ((ii) vs (iv)), there was no statistical difference in either CBF or CBFV on addition of 50% nitrous oxide. The correlation between changes in CBF and CBFV was not significant. We conclude that the use of nitrous oxide during isoflurane-induced hypotension has no significant effect on CBF, CBFV or ICP compared with the use of isoflurane alone.

Cardiotoxin II from Taiwan cobra venom, Naja naja atra. Structure in solution and comparison among homologous cardiotoxins

The three-dimensional structure in solution of cardiotoxin II, a membrane toxin from the venom of Taiwan cobra, Naja naja atra, was determined using 1H nuclear magnetic resonance spectroscopy and molecular modeling based on the hybrid distance geometry/dynamic simulated annealing technique. A complete sequence-specific proton assignment was obtained, and the secondary structures of the protein were determined from information on nuclear Overhauser effect connectivities, coupling constants, and hydrogen exchange were confirmed using the main-chain-directed strategy. Twelve simulated annealing structures found to be within a single family were selected based on the condition of distance constraint violation less than 0.02 nm and the dihedral angle violation less than 4 degrees. The average atomic root mean square deviation between the selected structures and their geometric average are 0.079 nm for the backbone atoms and 0.137 nm for all heavy atoms; they are 0.044 nm and 0.117 nm, respectively, when considering the secondary structural residues only. The molecule adopts a compact structure consisting of three major loops emerging from a globular head. These loops contain five strands to form double- and a triple-stranded antiparallel beta sheets. Comparisons are made between this structure and those of its homologous cardiotoxins in order to derive further information on their structural variations.

Hyponatremia and syndrome of inappropriate antidiuretic hormone secretion in adult spinal surgery

STUDY DESIGN

Patients undergoing spinal surgery were monitored for sodium balance, fluid type, and volume input and output during surgery and for the first 3 postoperative days.

OBJECTIVE

To prospectively document the true incidence of the syndrome of inappropriate antidiuretic hormone secretion and hyponatremia, and identify risk and protective factors for the development of the syndrome of inappropriate antidiuretic hormone secretion after spinal surgery.

METHODS

Data on medical history, surgical procedure, estimated blood loss, and volumes and types of intraoperative and postoperative fluids were collected on 116 consecutive spinal surgery patients during March to July 1992.

RESULTS

One hundred one spinal operations in 96 patients were evaluated. There were 48 males and 48 females, with a mean age of 52 years (range, 16 to 90 years). Hyponatremia developed in 45 (44.6%) patients. The etiology of hyponatremia was the syndrome of inappropriate antidiuretic hormone secretion in seven patients (6.9%), hypovolemia in 19 patients (18%), and other causes in six patients.

CONCLUSIONS

Spine patients are at risk for hyponatremia and the syndrome of inappropriate antidiuretic hormone secretion. The incidence of the syndrome of inappropriate antidiuretic hormone secretion was 6.9%. Serum sodium should be monitored postoperatively. Patients who undergo a revision operation have an approximately two to four times greater risk of being affected by the syndrome of inappropriate antidiuretic hormone secretion than those who have primary surgery.

Solution conformation of enopeptin A, a depsipeptide antibiotic, using 2D NMR and restrained molecular dynamics studies

Studies on the solution conformation of the cyclic depsipeptide antibiotic enopeptin A have been carried out using 2D NMR and molecular modelling techniques. The proton resonances of the antibiotic in DMSO-d6 have been assigned by the use of TOCSY and ROESY experiments. The interproton distance information obtained from the ROESY experiments have been used as the basis for elucidating the probable structures in solution. The restrained molecular dynamics technique was applied to calculate the structures in solution, and six resultant structures with fewer distance constraint violations were obtained that satisfy the experimental restraints very well. The conformation of the cyclic moiety of the molecules is well defined whereas the aliphatic chain segment is disordered.

Mutational spectrum in the p53 gene in bladder tumors from the endemic area of black foot disease in Taiwan

An elevated risk of bladder cancer has been reported in the endemic region of 'black foot disease' on the southwest coast of Taiwan and may be related to high arsenic levels in artesian well water. Thirteen urothelial tumors from this endemic region were examined for mutations in exons 5-8 of the p53 gene to identify the effects of possible exogenous factors at the DNA level. DNA was extracted from archival tissue after microdissection of tumors and analyzed by PCR-SSCP (polymerase chain reaction-based single strand conformation polymorphism), followed by direct sequencing. Eight cases (62%) showed mutations and 9 of the 10 point mutations observed were transitions. The type and position of the mutations were not significantly different when compared with the spectra of p53 mutations previously reported for transitional cell carcinomas (TCCs). However, two of the mutations were CGC-->CAC base changes at codon 175, a mutational hotspot for many tumor types but previously unreported in TCCs except in cases associated with inflammatory agents. Three of the tumors examined were found to contain double mutations, a relatively rare mutagenic event in human cancers. Our results suggest that the agents responsible for the high risk of bladder cancer in the black foot disease region may operate through an inflammation-based mechanism which increases the amount of DNA damage per mutagenic event.

Propofol does not reduce infarct volume in rats undergoing permanent middle cerebral artery occlusion

As propofol has been reported to have effects similar to those of thiopentone on cerebral blood flow, intracranial pressure and cerebral metabolic rate, we postulated that it might also have a protective effect on focal cerebral ischemia. This experiment was designed to test whether or not propofol can alter infarct volume resulting from permanent focal cerebral ischemia in rats. Forty-five rats were randomly assigned to three groups, all of which received xylaxine (5 mg kg-1 im) and ketamine (100 mg kg-1 ip) anesthesia. Rectal temperatures were controlled at 36-37 degrees C. A right temporal craniotomy was performed and the middle cerebral artery (MCA) was ligated with a 10-O suture. Both common carotid arteries (CCAs) were then occluded for 60 minutes using aneurysm clips. In Group 1 rats (n = 15), normal saline (1 ml kg-1 i.v.) was given right after MCA and CCAs ligation. In Group 2 rats (N = 15), propofol (10 mg kg-1 i.v. bolus) was given right after MCA and CCAs ligation. In Group 3 rats (n = 15), continuous intravenous infusion of propofol (16 mg kg-1 hr-1) was given for four hours following MCA and CCAs ligation, during which time mean arterial pressure was maintained approximately 90 mmHg. Twenty-four hours after ischemia, the brains were removed, frozen, sectioned and stained with 2% 2,3,5-triphenyltetrazolium chloride. The cross-sectional area of infarction on each brain slice was measured using computer imaging analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of focal ischemic brain injury on tail-flick latency in the rat

Tail-flick latency (TFL), a measure of response threshold to pain, was investigated in rats with focal ischemic brain injury resulting from middle cerebral artery occlusion (MCAO) as compared to sham and non-operative (non-op) groups on the 1st, 7th, 14th, 21st and 28th days following surgery or anesthesia. No significant differences were observed between MCAO and sham groups postoperatively, indicating focal ischemic insult induced by this model had no significant influence on TFL. Increased sensitivity to TFL in early postoperative period was shown when compared sham or MCAO with non-op group. The correlation between TFL and the time from surgery was statistically significant on the 1st and 7th days in sham group and the 1st, 7th and 14th days in MCAO group. We conclude that the focal ischemic injury resulting from middle cerebral artery occlusion that has no obvious neurologic effects does not alter pain threshold; however, surgical procedure increases postoperative sensitivity to pain stimulation.

Idiopathic autoimmune hemolytic anemia during pregnancy

A case of idiopathic autoimmune hemolytic anemia occurring during the third trimester of pregnancy is presented. The hemolytic process was quite severe in the mother but responded to steroid therapy. A healthy baby without evidence of hemolysis was delivered uneventfully through the vagina. We postulate the mechanism of the discuss the clinical picture, management of the disease and the possible effect on the fetus.

Two molecular pathways to transitional cell carcinoma of the bladder

Noninvasive transitional cell carcinomas of the bladder can have two distinct morphologies suggesting they contain different genetic alterations. Papillary transitional cell carcinomas (T(a) tumors) are often multifocal and only occasionally progress, whereas flat tumors (carcinomas in situ, CIS), frequently progress to invasive disease. We examined 216 bladder tumors of various stages and histopathologies for two genetic alterations previously described to be of importance in bladder tumorigenesis. Loss of heterozygosity of chromosome 9 was observed in 24 of 70 (34%) T(a) tumors but was present in only 3 of 24 (12%) CIS and dysplasia lesions (P = 0.04). In contrast, only 1 of 36 (3%) T(a) tumors contained a p53 gene mutation compared to 15 of 23 (65%) CIS and dysplasias (P < 0.001), a frequency comparable to that observed in muscle invasive tumors (25 of 49; 51%). The presence of p53 mutations in CIS and dysplasia could explain their propensities to progress since these mutations are known to destabilize the genome. Analysis of several tumor pairs involving a CIS and an invasive cancer provided evidence that the chromosome 9 alteration may in some cases be involved in the progression of CIS to more invasive tumors, in addition to its role in the initiation of T(a) tumors. However, the CIS and secondary tumor were found to contain different genetic alterations in some patients suggesting divergent progression pathways. Bladder carcinogenesis may therefore proceed through two distinct genetic alteration pathways responsible for generating superficial tumors with differing morphologies and pathologies.

Fibula osteoseptocutaneous flap for reconstruction of composite mandibular defects

The fibula osteoseptocutaneous flap is a versatile method for reconstruction of composite-tissue defects of the mandible. The vascularized fibula can be osteotomized to permit contouring of any mandibular defect. The skin flap is reliable and can be used to resurface intraoral, extraoral, or both intraoral and extraoral defects. Twenty-seven fibula osteoseptocutaneous flaps were used for composite mandibular reconstructions in 25 patients. All the defects were reconstructed primarily following resection of oral cancers (23), excision of radiation-induced osteonecrotic lesions (2), excision of a chronic osteomyelitic lesion (1), or postinfective mandibular hypoplasia (1). The mandibular defects were between 6 and 14 cm in length. The number of fibular osteotomy sites ranged from one to three. All patients had associated soft-tissue losses. Six of the reconstructions had only oral lining defects, and 1 had only an external facial defect, while 18 had both lining and skin defects. Five patients used the skin portion of the fibula osteoseptocutaneous flaps for both oral lining and external facial reconstruction, while 13 patients required a second simultaneous free skin or musculocutaneous flap because of the size of the defects. Four of these flaps used the distal runoff of the peroneal pedicles as the recipient vessels. There was one total flap failure (96.3 percent success). There were no instances of isolated partial or complete skin necrosis. All osteotomy sites healed primarily. The contour of the mandibles was good to excellent.

Purification and characterization of L-aminoacylase from Alcaligenes denitrificans DA181

The L-aminoacylase produced intracellularly by Alcaligenes denitrificans DA181 was purified to homogeneity. This enzyme had an apparent molecular weight of 80,000, and was composed of two subunits of identical molecular weight. Its isoelectric point was pH 5.1. The optimal reaction temperature and pH were 65 degrees C and 8.0, respectively. This enzyme showed specificity toward N-acetyl-derivative of hydrophobic L-amino acids with N-acetyl-L-valine as the favored substrate, followed by N-acetyl-L-alanine.

Continuous succinylcholine infusion and phase II block in short surgical procedures

The study was designed to observe continuous succinylcholine infusion and phase II block in short surgical procedures (duration < 90 min). The characteristics of neuromuscular blockade produced by continuous succinylcholine infusion were observed in 15 adult patients anesthetized with nitrous-oxide-isoflurane (0.7% end tidal concentration) and fentanyl, and were compared with the single-dose technique (n = 13) in recovery time. Ulnar nerve was stimulated supramaximally with repeated train-of-four (interval = 10 sec, frequency = 2 Hz) via surface electrodes at the wrist using an electromyographic monitor (Datex, Relaxograph, Finland). The infusion rate was adjusted to maintain the height of the first twitch (T1) in each train of four at 5-10% of control twitch height. The mean duration of infusion was 50.74 +/- 18.06 minutes. The steady state infusion rate required to maintain 90% to 95% twitch depression was 83.5 +/- 21.4 micrograms/kg/min. Five patients developed phase II block (T4/T1 < 0.5) designated as IB. The other ten did not develop phase II block as IA. Recovery times (T1 = 10.50%, 10-100%) between IA and IB were not statistically significantly different. The recovery time of train-of-four fade (T1 = 10% to T1 = 100% and train of four > 75%) was 5.73 +/- 0.43 minutes. However, recovery times between continuous infusion group and single dose group were significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Microsatellite instability in bladder cancer

Somatic instability at microsatellite repeats was detected in 6 of 200 transitional cell carcinomas of the bladder. Instabilities were apparent as changes in (GT)n repeat lengths on human chromosome 9 for four tumors and as alterations in a (CAG)n repeat in the androgen receptor gene on the X chromosome for three tumors. Single locus alterations were detected in three tumors, while three other tumors revealed changes in two or more loci. In one tumor we found microsatellite instability in all five loci analyzed on chromosome 9. The alterations detected were either minor 2-base pair changes or larger (> 2 base pairs) alterations in repeat length. All six tumors were low stage (Ta-T1), suggesting that these alterations can occur early in bladder tumorigenesis.

Prolonged fasting in pediatric outpatients does not cause hypoglycemia

Two hundred and thirty healthy children scheduled for receiving elective minor surgery were assigned into 4 different groups. Group I (small infant group) included 27 infants of age from 1 to 3 months (2.0 +/- 0.6 months), Group II (infant group) included 42 infants age from 3 to 12 months (7.4 +/- 2.8 months), Group III (pre-school children group) included 122 patients of age from 1 to 6 years (3.1 +/- 1.4 years). The remained 39 cases of age older than 6-years-old (8.0 +/- 1.5 years) were collected in group IV (old children group). All studied children were starved for at least 4, 6, or 8 hours in infants, pre-school children, and old children group, respectively, pre-operatively. The fasting time and fasting blood glucose levels of the 4 groups were 6.7 +/- 1.4 hours and 109.0 +/- 22.9 mg% in group I, 7.7 +/- 2.3 hours and 98.6 +/- 18.0 mg% in group II, 10.4 +/- 2.9 hours and 96.9 +/- 24.7 mg% in group III, and 12.6 +/- 2.6 hours and 95.7 +/- 20.5 mg% in group IV, respectively. No one in the 230 children had blood glucose less than 40 mg% even in 5 infants who were starved for 12 hours or more. Therefore, we concluded that preoperative starvation is well tolerated than the originally expected in the infants and children. The fasting time before anesthesia can be executed safely even though the operation schedule may not be right on time.