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This study investigated the ability of a protein F vaccine to reduce macroscopic evidence of lung damage and preserve pulmonary function in immunized animals in a rat model of chronic pulmonary infection caused by Pseudomonas aeruginosa . Other membrane protein F of P aeruginosa was purified by extraction from polyacrylamide gels of cell envelope proteins of the PAO1 immunotype 7 strain. Rats were immunized intramuscularly with either 25 μg of the purified protein F or bovine serum albumin on days 0 and 14 and then challenged on day 28 via intratracheal inoculation of agar beads containing cells of an immunotype 3 clinical isolate of P aeruginosa . Also, included was a noninfected control group which received only sterile agar beads. On day 35, the lungs were excised, pulmonary compliance measured, and the lungs examined macroscopically for the presence and severity of lesions. The protein F-immunized rats had a significant (p L =0.12±0.008), whereas C L of protein F-immunized rats (n=12, C L =0.17±0.006) was similar to that of noninfected control rats (n=5, C L =0.15±0.008). This study demonstrated that a protein F vaccine has the ability to decrease macroscopic lung lesions from infection and preserve pulmonary function in actively immunized rats upon subsequent challenge with P aeruginosa in this model of chronic lung infection.

The incidence of conjoined twins is rare, occurring in one in 50-80,000 live births. The rarity of the occurrence presents quite a management challenge. The first case in New Zealand of successfully separated thoraco-omphalagus twins, presenting top-to-tail, is described.

The keynote address at the Congress of the SA Society of Psychiatrists in 1994 1 , was delivered by Professor J.L. Cummings, on Neuropsychiatry-the state of the science. He said that structural imaging with CT and MRI and functional imaging using PET and SPECT, have greatly increased our knowledge of which parts of the brain, are affected in the various forms of neuropsychiatric disorders. He went on to say that Schizophrenia is associated with increased brain ventricular size and specific atrophy of the frontal lobes... (in schizophrenia). We have also begun to realise the importance of the frontal lobes with the basal ganglia and the thalamus, and then project back to the frontal lobes... in neuropsychiatry we are largely talking about system syndromes, and are not looking for a schizophrenic centre or a depression centre. At the SA Congress of Biological Psychiatry in 1991, Andreassen 2 had presented an important description of monovular-discordant-for-schizophrenia twins' brain studies by PET (Positron Emission Tomography) which suggested a high probability that schizophrenia might be a developmental disorder resultant upon a toxic or viral prior disorder. We report upon three siblings in a family, from whose kitchen food stores multiple mycotoxins were isolated. 3

Pleural effusion may result from many disorders, some of them serious. Fortunately, this body fluid is easily accessible, and knowledge of its characteristics is an important tool in diagnosing the underlying disease. The authors describe radiographic and laboratory tests to use in determining the source of the problem.

1. The effects of vagal stimulation and applied acetylcholine were compared on sinus venosus preparations of the toad, Bufo marinus, in which beating had been inhibited by adding the organic calcium antagonist nifedipine. 2. Bath-applied acetylcholine and vagal stimulation each caused membrane hyperpolarizations which were abolished by hyoscine. 3. Whereas the hyperpolarization that accompanied vagal stimulation was largely unaffected by barium ions, that produced by bath-applied acetylcholine was almost abolished. 4. Caesium ions also prevented the hyperpolarization produced by bath-applied acetylcholine but potentiated the responses to vagal stimulation. 5. The membrane resistance of arrested sinus venosus cells was found to be higher during vagal stimulation than in the absence of stimulation. In contrast when a similar hyperpolarization was produced by adding acetylcholine, the membrane resistance was found to be lower than in control solution. 6. The results are discussed in relation to the idea that neuronally released acetylcholine causes membrane hyperpolarization by suppressing inward current flow and applied acetylcholine acts to increase outward current flow.

Interleukin-1 (IL-1), a modulatory protein with immune and inflammatory functions, is spontaneously released by tissue macrophages in lower concentrations compared with peripheral blood monocytes. Conversely, in idiopathic pulmonary fibrosis, sarcoidosis, and certain inflammatory diseases, increased amounts of IL-1 are released by alveolar macrophages (AM). We examined IL-1 production by AM from patients with adult respiratory distress syndrome (ARDS) and compared it with that in patients with severe pneumonia requiring assisted ventilation, patients with pneumonia requiring parenteral antibiotics, and healthy control subjects. In vitro, ARDS AM released significantly more total IL-1 and IL-1 beta than did ARDS AM in patients with pneumonia and in control subjects. Moreover, after stimulation of these cells with 10 micrograms/ml of lipopolysaccharide (LPS), ARDS AM significantly increased release of IL-1 and IL-1 beta. AM from patients with severe pneumonia also released greater amounts of both IL-1 and IL-1 beta as fresh explants and after LPS stimulation when compared with control subjects. Incubation of AM with 250 U/ml human interferon-gamma (gamma IFN) was associated with less IL-1 beta release. However, stimulating AM from patients with ARDS and severe pneumonia with gamma IFN plus LPS enhanced the release of IL-1 beta compared with that in patients with pneumonia and in control subjects. ARDS AM released significantly more IL-1 beta than did all of the other groups. These results demonstrate that AM from patients with ARDS are capable of releasing significantly greater amounts of IL-1, which may be related to the progression of acute lung injury.

1. Intracellular recordings were made from pacemaker cells lying in the sino-atrial node of guinea-pigs. 2. Low-frequency vagal stimulation slowed the rate of generation of pacemaker action potentials; high-frequency stimulation stopped the generation of action potentials. 3. During vagal stimulation the rate of diastolic depolarization was reduced with the action potential otherwise unchanged: when the heart stopped the membrane potential of pacemaker cells settled to a value positive of the maximum diastolic potential. 4. In contrast, added acetylcholine caused membrane hyperpolarization and shortened the duration of action potentials. 5. The effects of both added acetylcholine and vagally released acetylcholine were abolished by hyoscine. 6. It is suggested that neurally released acetylcholine acts to change the balance between inward and outward current flow during diastole by modifying the properties of existing voltage-dependent channels. In contrast added acetylcholine appears to activate a different set of receptors which increase the potassium conductance of pacemaker cells.

The 899 offspring of Natal Indian diabetic couples are compared with the general Indian population. Diabetes was present in 25% of offspring aged 40– 49 as against 14.7% of the general population. The ratio of offspring diabetics to population diabetics diminished with age, suggesting that the genetic influence affects mainly age of onset of diabetes. “Old” and “young” diabetic couples had a similar proportion of diabetic children. Another similar comparison could be made between an inbred Tamil Indian family in Cape Town and the general population of Cape Hindus. More young diabetics were obese than old diabetics, in3 different racial groups and in both “clinic” and “survey” diabetics, whereas in the general population obesity is more common over age 40. Overweight may be a more important diabetes risk factor in young than in old people.

A study has been made of catecholamine stores that may be involved in cardiac regulation in the shark Heterodontus portusjacksoni. The anatomy of the anterior chromaffin bodies associated with the sympathetic chain is described. A fluoresent histochemical study shows that the chromaffin cells contain a monoamine, probably noradrenaline. The chromaffin cells have a fine structure comparable to that of chromaffin cells in other vertebrates. The heart is devoid of histochemically-demonstrable chromaffin cells or adrenergic nerve fibres, with the exception of a very sparse adrenergic innervation of the sinus venosus. It is argued that adrenergic control of the heart in Heterodontus might occur via amines released from the anterior chromaffin masses into the blood in the posterior cardinal sinus, which is then aspirated directly into the heart.

1. The effects of vagal stimulation and applied acetylcholine were compared on the isolated sinus venosus preparation of the toad, Bufo marinus. 2. The effects of applied acetylcholine and of low-frequency, or short bursts of high-frequency vagal stimulation were abolished by hyoscine. 3. When intracellular recordings were made from muscle cells of the sinus venosus, it was found that applied acetylcholine caused bradycardia and a cessation of the heart beat which was associated with membrane hyperpolarization and a reduction in the duration of the action potentials. Much of the effect of acetylcholine can be attributed to it causing an increase in potassium conductance, gK. 4. When slowing was produced by low-frequency vagal stimulation, only a small increase in maximum diastolic potential was detected. During vagal arrest the membrane potential settled to a potential positive of the control maximum diastolic potential. 5. In the presence of barium, much of the bradycardia associated with vagal stimulation persisted. Although the bradycardia produced by added acetylcholine also persisted in the presence of barium, the effects of acetylcholine that could be attributed to an increase in gK were abolished. 6. Addition of caesium ions produced bradycardia with membrane potential changes similar to those seen during vagal stimulation. 7. The results are discussed in relation to the idea that neuronally released acetylcholine reduces inward current flow during diastole. In contrast applied acetylcholine as well as reducing inward current flow during diastole also increases outward current flow by increasing gK.

Two groups of Indian “connubial off-spring” (children of diabetic couples) were investigated with standard oral and triamcinolone-augmented glucose tolerance tests (GTT); 110 in Durban and 20 in Cape Town together with smaller control groups. In Cape Town there was no appreciable difference between offspring and controls, but in Durban 14 of 76 offspring with normal standard GTT yielded diabetic augmented GTTs. Offspring with “border-line” standard GTT were usually “diabetic” on the augmented GTT, while in those with diabetic standard GTTs the blood glucose levels were generally unaltered by triamcinolone. Further analysis indicated that triamcinolone augmentation produced “diabetic” tests only in subjects with rather high (though still not diabetic) standard GTTs. A high triamsinolone test appeared no more discriminatory than a high-normal or borderline standard GTT. Triamcinolone tests were abnormal particularly among the older offspring whose standard GTTs were normal (though none was over 49).

It is the purpose of this paper to present a case in which a patient with no obvious systemic disease and not receiving any antibiotic or corticosteroid therapy developed oesophageal candidiasis. This led to complete obstruction to the passage of solids and fluids, needing direct removal of the obstruction. We should like to emphasize the signs of this condition through X-ray investigations of the oesophagus, which have been already described

RANDALL1 noted that the perfusion of water containing the teleost Tinca tinca with ethyl m-aminobenzoate (MS 222) caused an increase in heart and respiration rates. Although these increases did not correlate significantly, he concluded that there was probably some connexion between the cardiac and the respiratory centres in the central nervous system.