Electron-bombarded ⟨110⟩-oriented tungsten tips for stable tunneling electron emission

A clean tungsten (W) tip apex with a robust atomic plane is required for producing a stable tunneling electron emission under strong electric fields. Because a tip apex fabricated from a wire by aqueous chemical etching is covered by impurity layers, heating treatment in ultra-high vacuum is experimentally known to be necessary. However, strong heating frequently melts the tip apex and causes unstable electron emissions. We investigated quantitatively the tip apex and found a useful method to prepare a tip with stable tunneling electron emissions by controlling electron-bombardment heating power. Careful characterizations of the tip structures were performed with combinations of using field emission I-V curves, scanning electron microscopy, X-ray diffraction (transmitted Debye-Scherrer and Laue) with micro-parabola capillary, field ion microscopy, and field emission microscopy. Tips were chemically etched from (1) polycrystalline W wires (grain size ∼1000 nm) and (2) long-time heated W wires (grain size larger than 1 mm). Heating by 10-40 W (10 s) was found to be good enough to remove oxide layers and produced stable electron emission; however, around 60 W (10 s) heating was threshold power to increase the tip radius, typically +10 ± 5 nm (onset of melting). Further, the grain size of ∼1000 nm was necessary to obtain a conical shape tip apex.

Communicating by electrolarynx with a blind tetraplegic spinal cord injury patient on mechanical ventilation in the ICU

STUDY DESIGN

Single-subject case.

OBJECTIVES

To describe the atypical presentation of communication with a blind tetraplegic spinal cord injury patient on a respirator using an electrolarynx.

SETTING

Critical care center in Osaka, Japan.

METHODS

A 53-year-old blind man with tetraplegic spinal cord injury was admitted to our center. It was difficult for him to express his desires and to communicate with others about his severe condition and other details of his care. We began to use an electrolarynx to communicate with this patient because he could move his mouth.

RESULTS

With use of the electrolarynx, the patient gradually became better able to speak fluently by electrolarynx on the first day of use. The electrolarynx allowed us and his family to communicate with him. He was pleased with the improvement in communication.

CONCLUSION

An electrolarynx is a useful method for communicating with blind tetraplegic spinal cord injury patients on mechanical ventilation.

[Oozing type left ventricular rupture: report of three cases]

Two cases of postinfarction oozing type left ventricular rupture and a case of oozing type left ventricular rupture due to catheter perforation for left ventriculography are reported. The technique used to repair the rupture is fibrin glue-oxycellulose fixation method. The post operative course of three cases were uneventful. But left ventricular aneurysm remained in two cases.

[A left subclavian arterial aneurysm caused by fibromuscular dysplasia: a case report]

A 70-year-old man complained left supraclavicular pulsatile tumor. Angiography and CT revealed the left subclavian arterial aneurysm that was just behind the clavicle. The aneurysm was resected through a cross-clavicle incision and an 8 mm Hemashield graft was implanted. The pathological study showed change of fibromuscular dysplasia. The post-operative course was uneventful.

[Two case reports of recurrent mediastinitis with chronic mediastinal fistula successfully treated with muscle flap re-transposition]

We experienced two cases of recurrent poststernotomy mediastinitis with chronic mediastinal fistula. Both cases had already received muscle flaps for post operative mediastinitis. However, chronic mediastinal fistula appeared after nine months in the first case, and eleven months in the second case. We removed the infected tissue and the predgets, which were used on the ascending aorta. Then closed the wound by the muscle flap closure. The chronic fistula were closed, and the functional and cosmetic results were excellent.

Inhibition of trypsin, plasmin, thrombin and kallikrein by various esters of guanidino- and amidino-acids

Inhibitory effects of various phenolic esters of trans-4-guanidinomethylcyclohexanecarboxylic acid, amidino-piperidine-4-alkanoic acids or trans-4-amidinocyclohexane-4-alkanoic acids on trypsin, thrombin, plasmin and pancreatic kallikrein were examined. Their inhibitory effects were strongly affected by the acid portion and phenolic group constituting the esters. The effects of the acidic portion and phenolic group on the inhibitory effect varied with each protease; they were most effective on thrombin and plasmin and least effective on kallikrein. The inhibitory effect of these esters on trypsin was affected mainly by acid portion.

Antibacterial effects of esters of guanidino- and amidino-acids trypsin inhibitors

Inhibitory effects of various esters of trans-4-guanidinomethylcyclohexanecarboxylic acid and the 4-tert- butylphenyl esters of amidinopiperidine-4-alkanoic, trans-4- amidinocyclohexanealkanoic, trans-4-guanidinoethylcyclohexanecarboxylic and trans-4-guanidinocyclohexanealkanoic acids, all trypsin inhibitors, on the growth of E. coli, B. subtilis, S. aureus and S. epidermidis were examined. 4-tert-Butylphenyl esters strongly inhibited the growth of E. coli and the order of the inhibitory effects correlated with that for the inhibitory effects on proteinase In, which appears immediately before initiation of DNA synthesis in E. coli and closely correlates with the onset of DNA synthesis. No correlation was observed between the inhibitory effects and Ki values for trypsin. The 4-tert-butylphenyl esters also strongly inhibited B. subtilis, S. aureus and S. epidermidis, and the order, of the inhibitory effects on these bacteria roughly coincided with that on E. coli. The order of the inhibitory effects of each ester, on these bacteria was S. epidermidis > S. aureus > B. subtilis > E. coli. Among the esters examined, the biphenyl ester of trans-4-guanidinoethylcyclohexanecarboxylic acid was the most inhibitory on these four bacteria and proteinase In. Hydrolysis of tert-butyloxycarbonyl-L-valyl-L-prolyl-L-arginine 4-methylcoumarin-7-amide, which is a substrate for proteinase In, in crude extracts of E. coli, B. subtilis and S. epidermidis was examined. The order of this activity in these bacteria was E. coli > B. subtilis > S. epidermidis.

Effects of various esters of trans-4-guanidinomethylcyclohexanecarboxylic acid, trypsin inhibitors, on the growth of Bacillus subtilis

Various aromatic esters of trans-4-guanidinomethylcyclohexanecarboxylic acid (GMCHA), trypsin inhibitors, strongly inhibited the growth of Bacillus subtilis 558 and their effects were markedly affected by the species of substitution on the phenyl nucleus of the GMCHA phenyl esters. 4-tert-Butylphenyl ester of GMCHA (GMCHA-OPhtBu), a representative of various GMCHA esters, dose-dependently inhibited the growth of B. subtilis and DNA, RNA and protein syntheses in the cells. The growth inhibition was preceded by suppressive effect of GMCHA-OPhtBu on DNA synthesis. These results suggested the possible involvement of a trypsin-like proteinase in DNA synthesis. A trypsin-like proteinase was partially purified from B. subtilis 558 by DEAE-cellulose column chromatography, ammonium sulfate fractionation and successive chromatographies on Sephadex G-200, phenyl-Sepharose CL-4B, L-arginine-Sepharose 4B and Sephadex G-200 columns. The properties were compared with those of proteinase In, which momentarily appears just before the onset of DNA synthesis and seems to participate in the initiation of DNA replication, and which was purified from E. coli K-12 IAM 1264. The properties of the proteinase from B. subtilis 558 were similar to proteinase In, however, the molecular mass (110000) was different from that of the latter (66000). Various GMCHA esters strongly inhibited the proteinase activity and the order of the effects was closely correlated with that on the cell growth. The proteinase was tentatively called subtilis proteinase In.

Increased levels of tumor necrosis factor and interleukin 1 in bronchoalveolar lavage fluids from pigs infected with Mycoplasma hyopneumoniae

We examined the levels of tumor necrosis factor (TNF)-alpha and interleukin-1 (IL-1) in bronchoalveolar lavage fluids (BALF) from pigs experimentally infected with Mycoplasma hyopneumoniae using biological assays with WEHI-164 cells and D10.G4.1 cells, respectively. Increased TNF-alpha and IL-1 in BALF were found in infected pigs with gross and/or microscopic lesions. A time-course study suggested TNF-alpha and IL-1 to be persistently elevated in infected pigs. Their presence in BALF would thus appear to be associated with the development of pneumonic lesions in M. hyopneumoniae infected pigs.

Experimental pneumonia of pigs infected with Aujeszky's disease virus and Actinobacillus pleuropneumoniae

Experimental infections were induced out to examine whether Aujeszky's disease virus (ADV) infection in pigs results in a severe pneumonia by Actinobacillus pleuropneumoniae. Intranasal inoculation of ADV (10(6.9) median tissue culture infective dose/head) in 4-month-old primary specific-pathogen-free pigs was followed by the inoculation of A. pleuropneumoniae type 1 (10(3.1) or 10(5.1) colony-forming-units/head). The pigs inoculated with ADV alone developed clinical signs of Aujeszky's disease but not pneumonia, and those inoculated with A. pleuropneumoniae (10(3.1) CFU/head) alone did not develop clinical symptoms and lung lesions. Whereas all the pigs inoculated dually with ADV and A. pleuropneumoniae (10(3.1) CFU/head) showed severe or very severe clinical symptoms and moderate or severe pneumonia and one of them died. The pigs inoculated with A. pleuropneumoniae (10(5.1) CFU/head) alone had severe clinical symptoms and one of the 2 pigs died acutely. Furthermore, all of the 3 pigs inoculated with ADV and A. pleuropneumoniae (10(5.1) CFU/head) showed clinical symptoms and moderate or severe pneumonic lesions and one pig died of disease. It was concluded that the clinical symptoms of A. pleuropneumoniae became severer by concomitant infection with ADV.

Effect of trans-4-guanidinomethylcyclohexanecarboxylic acid 4-tert-butylphenyl ester, a trypsin inhibitor, on the growth of various strains of Escherichia coli

Similarly to Escherichia coli K-12 IAM 1264, trans-4- guanidinomethylcyclohexanecarboxylic acid 4-tert-butylphenyl ester (GMCHA-OPhtBu), a trypsin inhibitor, had a strong inhibitory effect on the growth of various strains of E. coli K-12, such as W 3350, AB 1157, JM 103, W 3110, C 600r-m- and C 600r+m+, preceded by suppressive effects of GMCHA-OPhtBu on DNA synthesis in these strains, although the inhibitory effects varied from strain to strain. These results suggested the possible involvement of a trypsin-like proteinase in DNA synthesis. A trypsin-like proteinase was partially purified from E. coli K-12 AB 1157 by ammonium fractionation and successive chromatographies on DEAE-cellulose, Sephadex G-100 and arginine-Sepharose 4B columns. The properties were compared with those of proteinase In, which instantly appears just before the onset of DNA synthesis and seems to participate in the initiation of DNA replication, and which was purified from E. coli K-12 IAM 1264. The proteinase from E. coli K-12 AB 1157 was identified with proteinase In. These results suggest that proteinase In must be widely distributed in various E. coli strains and plays a pivotal role in the onset of DNA replication.

[A case of quadricuspid aortic valve associated with mitral regurgitation]

A case of a 60-year-old man associated with quadricuspid aortic valve and mitral regurgitation is reported. The aortic valve consisted of three larger cusps and a small accessory cusp situated between the right and the non-coronary cusps. The aortic regurgitation resulted from malcoaptation of the four cusps and the mitral regurgitation resulted from annulus dilatation and thickening of the anterior leaflet. The surgical treatment was performed successfully by the aortic and mitral valve replacements with St. Jude Medical valves. The patient is doing well fifteen months postoperatively. Sixteen Japanese cases of quadricuspid aortic valve which were corrected surgically are reviewed.

A trypsin inhibitor trans-4-guanidinomethylcyclohexanecarboxylic acid 4-tert-butylphenyl ester suppresses the onset of DNA synthesis in Escherichia coli cells synchronized by phosphate starvation

trans-4-Guanidinomethylcyclohexanecarboxylic acid 4-tert-butylphenyl ester (GMCHA-OPh'Bu), a trypsin inhibitor, dose-dependently inhibited the growth of Escherichia coli K-12 IAM1264. Growth inhibition was preceded by dose- and time-dependent inhibition of DNA synthesis. These results strongly suggested participation of a trypsin-like proteinase in DNA synthesis. To clarify this suggestion, the effects of GMCHA-OPh'Bu on the doubling time and on the uptake of [methyl-3H]thymidine into DNA were examined with E. coli K-12 IAM1264 synchronized by a modified version of phosphate starvation. The synchrony lasted for two or three cycles with a doubling time of 55 min and a cell division period of 15 min. The cell cycle of E. coli was divided into three periods, cell division period (P), the period between cell division and initiation of chromosome replication (Q) and the period between initiation of chromosome replication and cell division (R). The R period was subdivided into two periods, R1 in which the rate of thymidine uptake into DNA was increasing, and R2 in which it was constant. The addition of GMCHA-OPh'Bu at the R1 period did not affect the already-initiated round of cell division, however, it retarded the next round. The addition at P, Q or R2 retarded the cell division in the same round, causing prolongation of the R1 period. A sharp and momentary appearance of trypsin-like proteinase activity peaked at the Q/R1 boundary in one cell cycle, and inhibition of the activity prolonged the R1 period.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case who developed mechanical pulsus alternans after Bentall's operation for annuloaortic ectasia]

Left ventricular pulsus alternans developed immediately after Bentall's operation in a 37-year-old patient with Marfan's syndrome accompanied by severe left heart failure due to annuloaortic ectasia. Echocardiographic examination suggested that this symptom was caused by alternating contractility based on left ventricular myocardial failure. Left heart failure disappeared early after operation, but pulsus alternans persisted until 7 months after operation, when EDVI decreased from 225 ml/m2 to 113 ml/m2.

Effects of synthetic trypsin inhibitors on the growth of Escherichia coli

The inhibitory effects of various aromatic esters of trans-4-guanidinomethylcyclohexanecarboxylic acid (GMCHA), potent trypsin inhibitors, on the growth of Escherichia coli were examined and the effects were compared with those of well known synthetic trypsin inhibitors. Various GMCHA esters strongly inhibited the growth of E. coli and their effects were markedly affected by the species and position of substitution on the phenyl nucleus of the GMCHA phenyl esters. No correlation was observed between the effects on the growth of E. coli and Ki's for trypsin. Inhibitory effects of benzamidine, phenylmethane sulfonylfluoride and diisopropyl fluorophosphate were less than 10% at 200 microM. 4-tert-Butylphenyl ester of GMCHA (GMCHA-OPhtBu), a representative of various GMCHA esters, dose-dependently inhibited the growth of E. coli and the growth inhibition was preceded by a dose- and time-dependent inhibition of DNA synthesis. Tosyl-L-lysine chloromethyl ketone (TLCK) and pentamidine isethionate, potent trypsin inhibitors, also dose-dependently inhibited the growth of E. coli and the DNA synthesis. However, their effects were transient and disappeared after a short while. These results indicate that the effects of TLCK and pentamidine isethionate differ from those of GMCHA esters. GMCHA-OPhtBu and pentamidine isethionate also inhibited RNA and protein synthesis.

Purification and characterization of proteinase In, a trypsin-like proteinase, in Escherichia coli

We previously found a trypsin-like proteinase which momentarily appears immediately before DNA synthesis in the cell cycle of Escherichia coli synchronized by phosphate starvation and which is closely related to the initiation of DNA replication (Kato, M., Irisawa, T., Morimoto, Y. and Muramatu, M., unpublished results). The proteinase was named proteinase In. It was purified approximately 2880-fold with a recovery of 15%. The isolated enzyme appeared homogeneous by gel filtration and electrophoresis. Its molecular mass was estimated by analytical gel filtration and SDS/PAGE as approximately 66 kDa. The isoelectric point of proteinase In is 4.9 and its optimal pH is approximately 9. Although protein In hydrolyzes fluorogenic substrate for trypsin, its hydrolytic activity seems markedly affected by amino-acid sequence lying towards the N-terminal from the P1 (lysine, arginine) residue. The proteinase does not hydrolyze N2-benzoyl-D,L-arginine-4-nitronanilide and fluorogenic substrates for chymotrypsin and elastase. The proteinase activity is inhibited by leupeptin, antipain and 4-nitrophenyl 4-guanidinobenzoate, but the effects of tosyl-L-lysine chloromethane, diisopropylfluorophosphate, benzamidine and pentamidine isethionate on the proteinase activity are weak or not inhibitory. Its activity is strongly affected in the presence of NaCl and KCl, and at a concentration of 1.5 M, these increase the activity 14-fold and 13-fold, respectively, above that without salt. Proteinase In was strongly inhibited by various esters of trans-4-guanidinomethylcyclohexanecarboxylic acid, and their inhibitory effects were roughly correlated with those on growth of E. coli. Proteinase activity was found in the cytoplasmic fraction.

[A case of Marfan's syndrome that required emergency Bentall's operation due to acute dissecting aortic aneurysm (DeBakey type II) following surgery of abdominal aortic aneurysm]

Graft replacement was performed in a 29-year-old man for an abdominal aortic aneurysm associated with Marfan's syndrome. Since the dissecting aortic aneurysm (DeBakey type II) accompanied by disruption of the right coronary artery developed 74 days after operation, the emergency Bentall's operation was successfully carried out with bypassing of the right coronary artery using a saphenous vein graft. Fifteen Japanese cases operated on for abdominal aortic aneurysm associated with Marfan's syndrome are reviewed, and the problems concerning surgery of abdominal aortic aneurysm and Bentall's operation are discussed.

[A case of surgical repair for combined septal perforation and cardiac rupture after myocardial infarction]

The successful surgical repair of the combination of septal perforation and cardiac rupture after myocardial infarction was underwent on a 73-year-old man. Complete correction could be performed under the fibrillated heart state employing cardiopulmonary bypass, resulted in the early postsurgical cardiac performance.

[Results of surgical repair by muscle flap closure for poststernotomy mediastinitis]

Between 1984 and 1991, 30 patients developed poststernotomy mediastinitis after cardiac or mediastinal operations. Sixteen of these patients were treated with debridement and open drainage or primary closure following mediastinal irrigation (drainage group). Fourteen patients were treated with debridement, and delayed or primary wound closure by the technique of pectoral or rectus abdominus muscle flap mobilization (muscle flap group). The purpose of this study was to compare the results of the different treatment of poststernotomy mediastinitis. Although the pre- and perioperative profile, complications and risk factors for mediastinal infection were the same, the mortality of muscle flap group was significantly lower than that of drainage group (Fisher exact probability test, p < 0.05). Pulmonary function of the patients who received muscle flap mobilization did not decrease from the function before surgery, despite the defect of sternal bony stabilization. We conclude that muscle flap mobilization may be a superior method as the treatment for poststernotomy mediastinitis after cardiac operations, and may not decrease respiratory function of the patients.

[Clinical backgrounds of six cases of childhood tuberculosis]

Clinical backgrounds of six children who entered Matsue National chest Hospital due to pulmonary tuberculosis and tuberculous pleuritis were investigated and the following results were obtained. 1) Of six children five had not received BCG vaccination. 2) There were two children who developed tuberculosis after the completion of chemoprophylaxis. 3) None was detected by the examination of the household of the source cases. 4) Both patients and doctors were responsible for the delay in detecting the source, which ranged between five and seventeen months in total. 5) Among the source cases there were two patients who were smear-negative but culture-positive. In view of the above observations it is suggested that BCG vaccination is important for the prevention of tuberculosis in children and that follow-up examinations should be continued after the completion of chemoprophylaxis. It should also be emphasized that early detection of the source case is imperative for the prevention of tuberculosis.

[Subdural hematoma following surgery of an aneurysm of the diverticulum of the ductus arteriosus with partial cardiopulmonary bypass]

The patient was a 72-year-old man, who had an aneurysm of the descending thoracic aorta with left recurrent laryngeal nerve palsy identified by preoperative examination. Thoracotomy revealed an aneurysm of a diverticulum of the ductus arteriosus measuring 2.7 X 3.4 cm. The aneurysm was excised under partial cardiopulmonary bypass and the defect of the aortic wall was repaired with a Dacron patch. Two days after surgery, he developed mild deterioration of consciousness and right hemiparesis. An acute subdural hematoma which covered the left frontal, parietal, and temporal lobes was found by CT examination. Craniotomy was performed 16 days after the previous surgery, and 100 g of hematoma was removed. Following craniotomy, complete recovery of cerebral function was observed. This appears to be a valuable report of a patient who developed acute subdural hematoma following surgery of aneurysms of the descending thoracic aorta with partial cardiopulmonary bypass.

[Successful mitral valve replacement for infective endocarditis in pregnancy]

A 27 weeks' pregnant women exhibited infective endocarditis due to alpha-streptococcus. As echocardiography showed vegetations on both mitral leaflets, cesarean section was performed at 35 weeks' gestation and a healthy male infant weighing 2,430 g was delivered. Antibiotic therapy was continued for fever after the cesarean section but macrohematuria and Osler's nodes developed. Emergency mitral valve replacement was performed successfully despite the presence of active infective endocarditis. She was discharged after completion of a 10-week course of antibiotic therapy.