Sequestration analysis for RNA polymerase I transcription factors with various deletion and point mutations reveals different functional regions of the mouse rRNA gene promoter.

We compared the ability of various deletion and substitution mutants of the mouse rRNA gene promoter to bind essential factors required for accurate transcription initiation by RNA polymerase I. Different amounts of a competitor template were first incubated with a mouse cell extract containing the whole complement of factors and RNA polymerase I, and then a tester template was added for the second incubation. Transcription was started by adding nucleoside triphosphates (one labeled), and the accurate transcripts were determined on a gel. The results indicated that the ability of 5' deletion mutants to sequester essential factors decreased almost concurrently with the impairment of in vitro transcription activity, whereas when the promoter sequence was removed from the 3' side, the transcription activity decreased earlier and more drastically than the sequestration ability. Similar, though not identical, results were obtained by preincubation with fraction D separated on a phosphocellulose column, indicating that the major factor which was sequestered was TFID, the species-dependent transcription initiation factor that binds first to the promoter in the initiation reaction (H. Kato, M. Nagamine, R. Kominami, and M. Muramatsu, Mol. Cell. Biol. 6:3418-3427, 1986). Compilation of the data suggests that a region inside the 5' half of the core promoter (-40 to -1) is essential for the binding of TFID. The 3' half of the promoter (-1 to downstream) is not essential for the binding of TFID but is highly important for an efficient transcription initiation. A strong down-mutant with a one-base substitution at -16 (G to A) had a reduced ability to bind to TFID, whereas a null mutant with a single base substitution at -7 (G to A) showed a binding ability similar to that of the wild-type promoter when tested with whole-cell extract. This null mutant, however, could not sequester the TFID well when incubated with fraction D alone, suggesting that the binding of TFID with this mutant is unstable in the absence of another factor(s) present in cell extract. The factor is not TFIA, which binds after TFID, because the addition of fraction A containing TFIA did not cause TFID to bind to the mutant. The availability of different mutants having lesions at different steps of transcription initiation will provide a powerful tool for the dissection of the initiation reaction of the RNA gene.

New 434-specific DNA binding protein copurified with the 434 tof protein from lambda imm434cI dv carrier cells of Escherichia coli.

A tof-like protein that has 434-specific DNA binding activity has been copurified with the 434 tof protein from lambda imm434cI dv carrier cells. The apparent molecular weight of the new 434-specific DNA binding protein is 9,000 to 9,500, a little higher than that of the 434 tof protein, as estimated by SDS gel electrophoresis. Amino acid analysis revealed the protein to be an arginine-rich component whereas the 434 tof protein is a lysine-rich component. The specific binding reaction of the new protein to lambda imm434dv DNA is distinct from that of the 434 tof protein in respect to the sigmoid shape of the binding curve and to the temperature dependency. This suggests that the specific binding to lambda imm434dv DNA observed with the new protein is due not to a trace of the 434 tof protein contaminating the new protein preparation but rather to the new protein itself. The NH2-terminal 11 residues of the new 434-specific DNA binding protein were sequenced by manual Edman degradation. This technique revealed that the new protein is not a fragment of the 434 tof, cII, or O protein or an NH2-terminal fragment of the cI repressor. The origin and the physiological roles of the new 434-specific DNA binding protein remain unknown.

Role of positive airway pressure on pulmonary acinar perfusion heterogeneity.

Perfusion of the pulmonary acinus has been shown to be generally homogeneous, but there is a significant component that is heterogeneous. To investigate the contribution of the alveolar septal capillary network to acinar perfusion heterogeneity, the passage of fluorescent dye boluses through the subpleural microcirculation of isolated dog lung lobes was videotaped using fluorescence microscopy. As the videotapes were replayed, dye-dilution curves were recorded from each of the tributary branches of Y-shaped venules that drained single acini. For each Y-shaped venule, the mean appearance time difference between the pair of tributary branches was calculated from the dye curves. When the complex septal capillary networks were derecruited by high positive airway pressure, venular perfusion became proportionally more homogeneous. This result shows that septal capillary resistance and pathlength differences are important contributors to intra-acinar perfusion heterogeneity.

The role of cGMP in the anti-aggregating properties of BY-1949, a novel dibenzoxazepine derivative.

The anti-aggregatory activity of a novel agent, BY-1949, 3-methoxy-11-methyldibenz (b,f) (1,4) oxazepine-8-carboxylic acid, was examined using rabbit platelets. Oral administration of BY-1949 (10 or 30 mg/kg) inhibited platelet aggregation induced by ADP, collagen, and arachidonate in a dose-related fashion. In in vitro studies, however, neither BY-1949 nor its major metabolites inhibited platelet aggregation, even at a concentration similar to that attained in plasma in vivo. With regard to the anti-aggregatory action of BY-1949, biochemical analysis revealed that BY-1949 preferentially augmented cyclic GMP (cGMP) formation, via inhibition of phosphodiesterase activity, without altering cyclic AMP (cAMP) formation. Furthermore, the in vitro anti-aggregatory activity was significantly enhanced when the platelets were concomitantly treated with nitric oxide (NO). Based on these results, it is suggested that the in vivo anti-aggregatory effects of BY-1949 are at least partly elicited via platelet/endothelium interactions, in which cGMP plays a pivotal role.

Errors in reporting cancer and other conditions by persons in a prospective study.

The hospital records of 553 men were compared with their medical histories obtained by interviews after hospitalization. Forty men had documentation of cancer in their hospital records stated that they had the specific condition. However, 21 other cancer patients did not give a positive history of their documented disease and 4 who stated that they had a malignancy did not have cancer according to their hospital records. In contrast to cancer, respondents overreported surgery for peptic ulcer and colorectal polypectomy. The greatest extent of agreement between the hospital record and the medical interview was noted for surgical patients with gallbladder disease; all 43 of these patients gave a positive history for this condition.

Heart failure in 3 patients with acromegaly: echocardiographic assessment.

We evaluated 3 patients with acromegaly who developed heart failure. Heart failure appeared to be due to acromegalic cardiomyopathy in 2 patients who did not have hypertension or evidence of coronary artery disease, and it was possibly due to acromegalic cardiomyopathy combined with familiar hypertrophic cardiomyopathy in 1 patient. The common echocardiographic findings in the present three cases were: 1) enlargement of the left atrium, 2) markedly dilated left ventricular cavity with diffuse hypokinesis, 3) decrease of indices of the left ventricular systolic function, and 4) no evidence of left ventricular hypertrophy. Echocardiographic findings in acromegaly with congestive heart failure resemble those of idiopathic dilated cardiomyopathy.

Assessment of reflection pulse wave in patients with cardiomyopathy: evaluation of noninvasive measurement of wave intensity.

OBJECTIVE: We assessed the reflection pressure wave using noninvasive measurement of wave intensity (WI) in patients with cardiomyopathy. METHODS AND RESULTS: Subjects included 8 patients with hypertrophic cardiomyopathy (HCM group) and 10 patients with dilated cardiomyopathy (DCM group). Twelve healthy subjects were used as a control group. By using a combined Doppler and echo-tracking system, changes in vascular diameter (dD) and blood flow velocity (dV) were recorded simultaneously at the common carotid artery and dD x dV was measured as WI. In the components of WI, the positive component of early systolic phase (FE) and the negative component following FE (B) were significantly reduced in the DCM group. There was a significant positive correlation between FE and B in all 3 groups. The appearance time of B was significantly shorter in the HCM group and significantly longer in the DCM group compared with the control group. CONCLUSIONS: It was suggested that the value of the reflection pressure wave was influenced by the left ventricular contractility, and that the effect of the reflection pressure wave appeared earlier in patients with HCM and later in patients with DCM compared with the control subjects.

[Effect of nitroglycerin and nicardipine on ICG excretion during halothane anesthesia].

We evaluated the effect of nitroglycerin and nicardipine on ICG excretion during halothane anesthesia in man. Induced hypotension with nitroglycerin during halothane anesthesia produced a significant prolongation in ICG excretion. No such significant prolongation occurred in the patients who received nicardipine. The results suggest that a reduction in hepatic blood flow during anesthesia may be much less in patients who receive halothane with nicardipine than in those who receive halothane with nitroglycerin.

[Effect of isoflurane and enflurane on ICG-clearance].

We performed ICG-test (indo-cyanine green test) during surgery to study the effect of isoflurane and enflurane on ICG clearance in human. When the systolic arterial pressure (SAP) was maintained at 70% of the preoperative base line value, a significant decrease in ICG clearance occurred in the patients who received enflurane. Isoflurane, on the contrary, did not cause such a decrease in the ICG clearance. We conclude that isoflurane may restore either the blood flow to the liver or the liver function and the liver may remove ICG from the blood much better under isoflurane than under enflurane.

[Perioperative blood glucose levels in children].

The perioperative blood glucose (BG) level may represent autonomic responses to various stresses by anesthesia and surgery. We studied the effects of regional blocks combined with general anesthesia on the BG response in pediatric patients. We could not find any significant differences in BG levels between blocked and non-blocked patients. However, BG levels of the children who had been hysterical or crying during the induction of anesthesia were significantly higher than those of the children who had been calm or sleeping. Forty healthy children, aged 1-3 yrs who were scheduled for elective urological surgery were studied. Anesthesia was induced with halothane in oxygen. The anesthesiologist recorded the children's attitude before and during the induction of anesthesia, and described as "calm or asleep (Calm-group), and hysterical or crying (Crying-group)". Patients were assigned randomly to two groups as follow; Group A (n = 20): receiving nerve blocks, Group B (n = 20): without the blocks. The anesthesia was maintained with 1-2.5% halothane in oxygen required to maintain the hemodynamic parameters within 10% of baseline value before surgery. Both groups received lactated-Ringer's solution during the study period. The venous BG levels were determined 5 times, i.e. immediately after asleep, 5, 15, 30 minutes after skin incision and at the conclusion of surgery. BG levels were compared between groups using Mann-Whitney Test. There was no significant difference in BG levels between Group A and B throughout the study period. But BG values of Crying-group (n = 9) were significantly higher than those of Calm-group (n = 31) during perioperative period.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effect of the prone position on ICG excretion during normotensive or hypotensive isoflurane anesthesia].

We evaluated the effect of prone position on ICG excretion during normotensive and hypotensive isoflurane anesthesia. In supine position, either normotensive or hypotensive anesthesia produced no significant prolongation in ICG excretion. In prone position, however, both normotensive and hypotensive anesthesia caused a significant prolongation in the excretion. The results suggest that prone position decreases the hepatic blood flow or hepatic function during isoflurane anesthesia.

[Effect of dopamine administration on ICG-disappearance rate during prone position anesthesia].

We evaluated the effect of dopamine administration (3 micrograms.kg-1.min-1) on ICG-disappearance rate during prone position in 10 patients undergoing elective spinal cord surgery. Anesthesia was maintained with isoflurane and 50% nitrous oxide in oxygen. ICG-disappearance rate was determined at 3 points, i.e., the day before surgery, during prone position and during the administration of dopamine. Systolic arterial pressure showed no significant difference before and during dopamine administration. ICG-disappearance rate during prone position was significantly lower than the preoperative value. However, ICG-disappearance rate showed no significant difference during dopamine administration and preoperative period. We conclude that dopamine administration may attenuate the depressant effect of the prone position on the hepatic blood flow.

[ICG-disappearance rate during sevoflurane- or neurolept anesthesia].

We evaluated the effect of sevoflurane or neuroleptanesthesia on ICG-disappearance rate in 22 patients undergoing elective extra-abdominal surgery. We divided the patients into three groups, i.e., SN-group (n = 8), SH-group (n = 8) and NLA-group (n = 6). Systolic arterial pressure (SAP) in the patients of SN-group or SH-group was maintained with sevoflurane at about 100% or 70% of the preoperative value respectively. There was no significant difference in SAP between SN-group and NLA-group. In SN-group and NLA-group, there was no significant difference in the ICG-disappearance rate between the values during anesthesia and those during preoperative period. In SH-group, however, it was significantly lower than the preoperative value. We conclude that, when normal systolic arterial pressure can be maintained, sevoflurane or neuroleptanesthesia has little effect on the liver function and hepatic blood flow. Sevoflurane anesthesia with 70% of preoperative SAP, however, may depress the liver function and hepatic blood flow.

[Interaction of halothane and PGE1 on ICG excretion].

We performed ICG-test during surgery to study the effect of halothane on ICG excretion in humans. We also evaluated the effect of PGE1 on ICG excretion concomitantly used during halothane anesthesia. A significant decrease in ICG clearance occurred in the patients who received only halothane to reduce the systolic arterial pressure (SAP) to 70% of the preoperative value. The reduction in SAP induced by PGE1 together with halothane, however, did not decrease the ICG clearance rate. We conclude that halothane may decrease the hepatic blood flow, but PGE1 may neutralize the effect of halothane, and maintain the hepatic blood flow in man.

[Anesthesia for a patient with Bloom's syndrome].

Bloom's syndrome (BS) is a rare autosomal recessive disorder. The disease is due to chromosome breakage and recombination. The principal features of the syndrome are short stature of prenatal onset, a photosensitive telangiectasic erythema of the face and a marked predisposition to the development of malignant diseases. We are unaware of any previous report of the anesthetic management of a BS patient. In this paper, we reported the anesthetic experience of a male patient (37-yr-old, 26 kg, 136 cm) with Bloom's syndrome who underwent emergency laparotomy. The awake laryngoscopy was carried out, but we could not see the vocal cord directly. The trachea was blindly intubated and anesthesia was induced and maintained with fentanyl, vecuronium and enflurane in 100% oxygen. In a BS patient we should pay attention to potential difficulties with mask fit and laryngoscopy.

[Effect of deliberate hypotension with PGE1 on PaO2 in pediatric patients].

We compared the effect of deliberate hypotension with PGE1 on PaO2 between pediatric and adult patients. Seven children, aged 3-9 yrs and 10 adults, aged 35-65 yrs who were scheduled for elective head and neck surgeries were studied. Anesthesia was maintained with enflurane, 50% N2O in oxygen and supplemental infusion of fentanyl. Ventilation was controlled to maintain PaCO2 at 35-40 mmHg. Hypotension was induced with continuous infusion of PGE1 and the systolic blood pressure was maintained at 70% of the presurgical value. Blood gases were measured three times, i.e. before, during, and after hypotension. The hypotension in adults caused a significant reduction in PaO2. In children, on the contrary, PaO2 was not affected by the hypotension. The results suggest that intrapulmonary shunting is smaller in children than in adults during PGE1-induced hypotension.

[The CO2 absorption capacity and color indication of a newly developed soda lime (Wakolime)].

The CO2 absorption capacity and the color change of ethyl violet (color indicator) of Wakolime A (newer type). Wakolime (older type), and Sorb 800 were studied under the clinical anesthetic condition. A two chamber canister was filled with soda lime and anesthetic gas flowed upward through the canister at the rate of 4 ml.min-1. The wall temperature of each chamber was measured with surface temperature sensing device. After 30 hours of use, the colored soda lime in the first chamber was examined with a color analyzer. The change of wall temperature indicated that the CO2 absorption capacity of Sorb 800 was the largest and that of Wakolime was the smallest among the three. The indicator color of both Wakolime A and Sorb 800 was clearer and of more vivid violet than that of Wakolime, which was dull and grayish. These results indicated that Wakolime A is superior in the CO2 absorption capacity and color indication to Wakolime.

[Anesthetic care of a patient intoxicated with thinner].

This is a report of a 28 year old male who underwent emergency laparotomy. He had a history of asthma and chronic abuse of thinner (toluene), and he stabbed himself after acute intoxication by the drug. Anesthesia was induced and maintained by halothane and oxygen. Vecuronium was used for muscle relaxation. Abnormal EKG was seen during perioperative period: A-V dissociation and incomplete RBBB. After emergence from anesthesia, so called "flash back" phenomenon was observed but this was controlled by diazepam. Since the chronic abuse of toluene causes organic changes in many vital organs, we must take special precautions when we anesthetize a patient with thinner intoxication: (1) toluene has a negative inotropic effect and also delays the S-A and A-V conduction rate, which may potentiate the cardiac effect of inhalation anesthetics; (2) toluene causes liver damages; and (3) the patient may experience "flash back" phenomenon.

[Liquid crystal thermography; a reliable method for detecting soda lime exhaustion].

The dynamic and functional state of soda lime can be more precisely assessed by measuring changes in wall temperatures of the absorption chambers rather than observing color change of the soda lime granules. We demonstrated in this report that the liquid crystal thermometer is an inexpensive and reliable measuring device for this purpose.

[Outcomes of primary angioplasty in patients aged 85 years old and older who have acute myocardial infarction].

Outcomes of primary angioplasty in 6 elderly patients with acute myocardial infarction who were admitted to the hospital between July of 1994 and June of 1997 were reviewed retrospectively. Emergency coronary angiography was done in 7 of 16 patients (44%) who were at least 85 years old and primary angioplasty was done in 6 patients (38%). Dilatation was successful in all 6 patients. Congestive heart failure occurred in 4 patients and cardiogenic shock occurred in 1 patient, but no patient died during hospitalization. Blood transfusion and surgical resection were done in 1 patient because of a giant hematoma and pseudoaneurysm at the puncture site. Although the creatinine level increased after angioplasty in all 6 patients, dialysis therapy was not needed. All patients were alive and none had angina at follow-up (mean follow-up period = 16.5 months). Primary angioplasty was successful in patients at least 85 years old; both short-term and long-term outcomes were good. Primary angioplasty should be considered to be an effective treatment for acute myocardial infarction in people 85 years old and older.