Peptidic p-nitroanilide substrates of interleukin-1β-converting enzyme

Peptidic p-nitroanilides are useful colorimetric substrates for enzymes. With the aim of developing a convenient, quantitative assay for inhibitors of interleukin-1β-converting enzyme (ICE), we have explored three approaches to the synthesis of peptidic p-nitroanilides relevant to this enzyme. The first approach involved a late stage oxidation of a p-aminoanilide such as CbzValAlaAsp(β-tert-butyl)-p-(t-Boc-amino)anilide. The second and third approaches used the preformed amino acid p-nitroanilides HAsp-p-nitroanilide hydrochloride and HAsp(7beta;-tert-butyl)-p-nitroanilide which were coupled iteratively with preactivated amino acid derivatives or with an appropriate peptide, respectively. While each approach had it merits and limitations, all three produced p-nitroanilides that were substrates for ICE.     

Genetic Epidemiology in Child Psychiatric Nursing Tourette's Syndrome as a Model

Recent discoveries in the field of molecular biology and increased attention to genetic epidemiology have stimulated renewed interest in the genetics of psychiatric disorders. Tourette's syndrome, a neuropsychiatric disorder characterized by motor and phonic tics, is used as a model to describe the research strategies employed in the genetic epidemiology of child psychiatric disorders. The relevance of genetic research findings to child psychiatric nursing is also discussed.     

The Radiology of Bronchial Atresia Radiographic,CT and Bronchography Correlation

We examined two patients with bronchial atresia. Both cases involved the left upper lobe: the anterior and the lingular segments respectively. Mucoid impaction and hyperinflation seen with radiography or computed tomography (CT) are typical findings. Bronchography in conjunction with bronchoscopy is an efficient means to confirm the atretic segment as well as the patency of the proximal bronchi respectively.     

Aggregation and Surface Properties of Synthetic Double-chain Non-ionic Surfactants in Aqueous Solution

Double-chain non-ionic surfactants have been synthesized with the general formula 2C_nMPEG₇₅₀, where n is the number of carbons in the alkyl chains and 750 is the molecular weight of the monomethoxypolyoxyethylene (MPEG) head group. The aggregation and surface properties in dilute aqueous solution (<1.0% w/w) of surfactants with n = 8, 10 and 12 have been determined. Each of the surfactants formed clear, foaming, non-birefringent solutions. Total-intensity light scattering indicated the presence of micelles with aggregation numbers of 36, 68 and 74 for the 2C₈, 2C₁₀ and 2C₁₂ surfactants, respectively, whereas photon-correlation studies yielded radii, assuming spherical aggregates, of 59–103 Å. Surface-tension measurements gave critical micelle concentrations for the surfactants in the range 1–15–7–24 × 10^?6 m; these, as expected, decreased when the number of carbon atoms in the alkyl chains was increased. Such studies are important in the design of new surfactants as vehicles for drug delivery because it is imperative to be able to predict the type of aggregate formed by a surfactant.     

Lumbar Facet Joint Block: A Simplified Technique

Lumbar facet joint arthropathy is now recognized as an important cause of lumbago and sciatica. Intra-articular block with local anaesthetics and steroids can confirm symptomatic facet arthropathy. A simplified technique for lumbar facet joint block is described to facilitate safe and rapid intra-articular therapy.     

The Automatic Implantable Cardioverter-Defibrillator

The automatic implantable cardioverter-defibrillator is an electronic device designed to monitor the heart continuously, to identify malignant ventricular tachyarrhythmias, and then to deliver effective countershock to restore normal rhythm. There are two defibrillating electrodes which are also used for waveform analysis; one is located in the superior vena cava, the other is placed over the cardiac apex. A third bipolar right ventricular electrode serves for rate counting and R-wave synchronization. When ventricular fibrillation occurs, a 25 joule pulse is delivered; when ventricular tachycardia faster than a preset rate is detected, the discharge is R-wave synchronized. The device can recycle three times if required. Special batteries can deliver over 100 shocks or provide a 3-year monitoring life. Implantation of the device is made either through a thoracotomy or by a subxiphoid approach. Thus far, the device has been implanted in 160 patients with a follow-up of 42 months. Acceleration of ventricular tachycardia to a faster rhythm or to ventricular fibrillation occurred only rarely and is dealt with most successfully through recycling. Actuarial analysis of the initial 52 patients has indicated 22.9% one-year total mortality, a 52% decrease from the 48% mortality that would be expected in the same group of patients without the device: the mortality attributed to arrhythmias was only 8.5%. In conclusion, the automatic cardioverter-defibrillator can reliably identify and correct potentially lethal ventricular tachyarrhythmias, leading to a substantial increase in survival in properly selected high-risk patients.     

Electrophysiologic Properties of Cimetidine in Man

Severe bradycardia has been reported with the use of cimetidine. This observation has been explained by histamines' known action in increasing the contraction rate of the spontaneously beating right atrium, strips of ventricular muscle, and whole heart of guinea pigs. Histamine can also produce cardiac arrhythmias in animals. There is evidence for H2 receptors in the heart. Black and his associates have shown that the characteristic effect of histamine on isolated guinea pig atrium could be selectively blocked by anti-H2 drugs. Thus cimetidine probably can produce a sinus bradycardia by blocking the H2-receptor site in the heart. Recently Engel and Luck reported that 300 mgs of intravenously administered cimetidine did not affect heart rate, sinus node recovery time, or sinoatrial conduction time. These workers concluded that there is insufficient evidence to demonstrate that cimetidine caused appreciable sinus node dysfunction in man. In view of the disparity in these reports, we investigated the effects of 300 mgs of intravenously administered cimetidine on the human conduction system.     

The relationship of the basophil to blood histamine in man

Data are presented correlating 22 determinations of the histamine content of blood in patients with chronic granulocytic leukemia with (1) the basophils (2) the other myeloid granulocytes. Expressing the histamine in each caseon the basis of the amount in 10⁸ granulocytes, there is a readily evident positivecorrelation with the basophil percentage and a negative correlation with thepercentage of other myeloid elements. This is strikingly apparent in instanceswhere blood with a very high percentage of basophils was analyzed. The dataindicate that in chronic granulocytic leukemia, the basophil is predominantlyand, perhaps exclusively, responsible for the marked elevations in blood histamine. Inferentially, it appears probable that this cell type, though small innumbers, may be the principal carrier of histamine in non-leukemic blood.

Submitted on April 26, 1954 Accepted on May 24, 1954     

Intrathoracic Pressure as a Tourniquet Technic to Tamponade Bleeding Esophageal Varices

The authors' report observations on 79 cases of esophagovariceal bleeding in which ten cases were subjected to an intrathoracic tourniquet maneuver of increasing intrathoracic pressure. All esophagovariceal bleeding ceased following the maneuver. An established maneuver safety limit (holding mean transmural CVP to no higher than 4.0 cm H2O) insured cardiac output maintenance and guaranteed against maneuver-generated morbidity. The authors conclude the cessation of the bleeding from esophageal varices observed is the combined result of tourniquet-tamponade by direct venous air compression on the bleeding varices as well as general esophageal compression.     

A DECADE INDECADENT

This paper attempts to analyse the relationship between the pulp and paper industry in Australia, and State forestry. Victorian conditions are taken as an example.

The industry has an interest, at least equal to the State forestry authorities, in sustained yield forestry, and at the same time it can play an important role in assisting the State to work towards management for sustained yield. In many of the forests which have been cut for mill logs during the past decade, the volume of cull wood, both standing and on the ground, has often presented a serious obstacle to the establishment and development of satisfactory regeneration. The ability of the pulp and paper industry to utilize much of this material is of great potential value to State forestry.

The amount and type of this logging residue that can be used is limited by the economic conditions and disadvantages which handicap the Australian industry. Recent work shows that wood quality in relation to the quality of the finished product also exercises an economic, as well as a technical influence.

Because of these factors it is essential for the industry to have a substantial amount of high quality wood in its raw material furnish, and this introduces the novel concept of management of State forests primarily for pulpwood production. At first sight, this prospect may appear most undesirable to many State foresters, but there are several considerations which make it at least worth thinking about, if not attractive.