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ACADEMIC CHANGES IN NEW ZEALAND
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apnoeic period, starting when the PaCO2 and PaO2 were normal, resulted in a build-up of CO2 and a lowering of PaO2 which eventually stimulated the sluggish respiratory centre, the subsequent hyperpnoeic phase correcting the blood gases so that apnoea once again followed. Brown and Plum report that all their patients had
respiratory alkalosis with maximal PaC02 coinciding with peak dyspnaea and minimal PaC02 with the beginning of the apnoeic phase. They found that, compared with normal subjects, there wasan enhanced respiratory response to PaC02 resulting in a rapid blowing-off of CO2 in the hyperpnceic phase, and this led to the subsequent apnoeic phase. With the decrease of the PaCO2 the pH rose and as a result of the Bohr effect$the relative oxygen saturation rose. The PaO2, however, remained low because of the alkalosis and, whereas normally the carotid body receptors provide little ventilatory stimulation, this was not so in patients with C.S.R., in whom the hyperapnoeic phase continued even when the PaCO2 had fallen to
low levels.
Karp et al.9 found in the hyperventilation phase a decreased arteriovenous oxygen difference, compared with that of the apnoeic phase, from which they deduce that in the hyperventilation phase cerebral blood-flow is increased. They point out that this decreased arteriovenous oxygen difference is unlikely to indicate reduced oxygen utilisation by the brain, because they recorded in the hyperventilation phase a correspondingly increased mental alertness, more normal electroencephalographic tracings. Moreover, they found a decreased cerebral circulation-time. Relating the changes in the arterial blood-gas tensions to the ventilatory and apnoeic phases of c.s.R., they suggest that the hypoxaemia and increase in the PaCO2 in the ventilatory phase are probably responsible for cerebral vasodilatation and hence increased cerebral blood-flow. They conclude that the varying blood-flow may be one more manifestation of the phasic activity in the central nervous system responsible for c.s.R. BRITISH EMPIRE CANCER CAMPAIGN
THE report for 1960 of the British Empire Cancer describes the work in some forty institutes financed either wholly or partly by grants totalling almost Sl.000,000. Two main themes emerge: chemotherapy with various alkylating agents, and radiotherapy with associated work in radiobiology and radiation chemistry.
Campaign 10
From the clinical point of view there is little that is the use of alkylating agents; but the intensive fundamental research now in progress may eventually lead to improvements in the selectivity and effectiveness of compounds of this type.
new on
As regards radiotherapy, a great deal of interest is centred on the effect of oxygen tension on the response of An extensive normal and neoplastic cells to X rays. investigation on the long-term effects of a single wholebody irradiation in mice is reported from the department of physics at St. Bartholomew’s Hospital, London. Leukaemia accounted for the largest percentage increase of disease, with pulmonary tumours sharing the largest decrease. These changes in incidence are due to changes in the time of onset; and, with correction for this change in time, the percentage incidence of all causes of death is Bohr, C., Hasselbalch, K., Krogh, A. Arch. Physiol. skand. 1904, 16, 402. Karp, H. R., Sieker, H. O., Heyman, A. Amer. J. Med. 1961, 30, 861. 10. Issued by the British Empire Cancer Campaign, 11, Grosvenor Crescent, London, S.W.1. 8. 9.
the same in the irradiated mice as in the controls. It is concluded that radiation shortens life, not by inducing specific diseases, but by bringing all causes of death forward in time without altering the relative risks, and it is suggested that radiation is a common causal factor in a wide variety of diseases, rather than a specific carcinogen. Other carcinogens may possibly act in a similar fashion, by accelerating the development of neoplasms rather than by producing them. On the vexed question of the correlation between medical X rays and leukaemia. Dr. Alice Stewart reports that there are two distinct xtiological varieties of leukaemia, only one of which is numerically important in childhood. This type occurs in children who are especially prone to pneumonia and other pyogenic infections-which explains a previous finding that in the leuksemic group studied pneumonia was given as a reason for X rays more often than in other groups. It is suggested that there is a premalignant defect in the genes which control the development of the reticulo-endothelial system, and that the abnormal stem cells derived from these genes undergo further changes and become malignant. Before the of antibiotics these children have died of discovery might pneumonia. Nowadays, if the infection is survived, the children may die of leukaemia. The second type of leuksemia in children ? rare and may be caused by irradiation in utero. Reports from several centres suggests that stalemate has been reached as far as the endocrine treatment of cancer is concerned. Enough large series of patients have been studied to provide a clear idea about the clinical usefulness of the various forms of such treatment, but there is still little direct experimental evidence concerning the mechanisms by which these affect the course of the disease. Emmens and his colleagues in Sydney report that the most potent antioestrogen so far found in their work is dimethyl stilboestrol and a clinical trial of the effectiveness of this compound in mastitis is in progress. The overall impression from the report is that there is no sign of a fundamental discovery which holds out any promise of a new era in the treatment of cancer. Rather, the impression is one of inching forward by vast. and painful effort. ACADEMIC CHANGES IN NEW ZEALAND
THE University of New Zealand is to disappear at the end of this year, and, in preparation for this honourable dissolution, it has already handed over its examining powers to its component institutions the University of Otago at Dunedin, the University of Canterbury, the Victoria University of Wellington, and the University of Auckland. The University of Auckland has been designated as the seat of New Zealand’s second medical school-there is already one at Dunedin-and Sir Douglas Robb, F.R.C.S., has been elected chancellor. As yet the Government has not authorised the launching of the school, but the university has lately set up a faculty of medicine to coordinate existing postgraduate facilities and to prepare the way. A steering committee has been studying the problem for over two years, and the Auckland Medical Research Foundation, set up in 1957, will be of great assistance. Mr. A. C. H. BELL has been re-elected president of the Royal College of Obstetricians and Gynxcologists.
apnoeic period, starting when the PaCO2 and PaO2 were normal, resulted in a build-up of CO2 and a lowering of PaO2 which eventually stimulated the sluggish respiratory centre, the subsequent hyperpnoeic phase correcting the blood gases so that apnoea once again followed. Brown and Plum report that all their patients had
respiratory alkalosis with maximal PaC02 coinciding with peak dyspnaea and minimal PaC02 with the beginning of the apnoeic phase. They found that, compared with normal subjects, there wasan enhanced respiratory response to PaC02 resulting in a rapid blowing-off of CO2 in the hyperpnceic phase, and this led to the subsequent apnoeic phase. With the decrease of the PaCO2 the pH rose and as a result of the Bohr effect$the relative oxygen saturation rose. The PaO2, however, remained low because of the alkalosis and, whereas normally the carotid body receptors provide little ventilatory stimulation, this was not so in patients with C.S.R., in whom the hyperapnoeic phase continued even when the PaCO2 had fallen to
low levels.
Karp et al.9 found in the hyperventilation phase a decreased arteriovenous oxygen difference, compared with that of the apnoeic phase, from which they deduce that in the hyperventilation phase cerebral blood-flow is increased. They point out that this decreased arteriovenous oxygen difference is unlikely to indicate reduced oxygen utilisation by the brain, because they recorded in the hyperventilation phase a correspondingly increased mental alertness, more normal electroencephalographic tracings. Moreover, they found a decreased cerebral circulation-time. Relating the changes in the arterial blood-gas tensions to the ventilatory and apnoeic phases of c.s.R., they suggest that the hypoxaemia and increase in the PaCO2 in the ventilatory phase are probably responsible for cerebral vasodilatation and hence increased cerebral blood-flow. They conclude that the varying blood-flow may be one more manifestation of the phasic activity in the central nervous system responsible for c.s.R. BRITISH EMPIRE CANCER CAMPAIGN
THE report for 1960 of the British Empire Cancer describes the work in some forty institutes financed either wholly or partly by grants totalling almost Sl.000,000. Two main themes emerge: chemotherapy with various alkylating agents, and radiotherapy with associated work in radiobiology and radiation chemistry.
Campaign 10
From the clinical point of view there is little that is the use of alkylating agents; but the intensive fundamental research now in progress may eventually lead to improvements in the selectivity and effectiveness of compounds of this type.
new on
As regards radiotherapy, a great deal of interest is centred on the effect of oxygen tension on the response of An extensive normal and neoplastic cells to X rays. investigation on the long-term effects of a single wholebody irradiation in mice is reported from the department of physics at St. Bartholomew’s Hospital, London. Leukaemia accounted for the largest percentage increase of disease, with pulmonary tumours sharing the largest decrease. These changes in incidence are due to changes in the time of onset; and, with correction for this change in time, the percentage incidence of all causes of death is Bohr, C., Hasselbalch, K., Krogh, A. Arch. Physiol. skand. 1904, 16, 402. Karp, H. R., Sieker, H. O., Heyman, A. Amer. J. Med. 1961, 30, 861. 10. Issued by the British Empire Cancer Campaign, 11, Grosvenor Crescent, London, S.W.1. 8. 9.
the same in the irradiated mice as in the controls. It is concluded that radiation shortens life, not by inducing specific diseases, but by bringing all causes of death forward in time without altering the relative risks, and it is suggested that radiation is a common causal factor in a wide variety of diseases, rather than a specific carcinogen. Other carcinogens may possibly act in a similar fashion, by accelerating the development of neoplasms rather than by producing them. On the vexed question of the correlation between medical X rays and leukaemia. Dr. Alice Stewart reports that there are two distinct xtiological varieties of leukaemia, only one of which is numerically important in childhood. This type occurs in children who are especially prone to pneumonia and other pyogenic infections-which explains a previous finding that in the leuksemic group studied pneumonia was given as a reason for X rays more often than in other groups. It is suggested that there is a premalignant defect in the genes which control the development of the reticulo-endothelial system, and that the abnormal stem cells derived from these genes undergo further changes and become malignant. Before the of antibiotics these children have died of discovery might pneumonia. Nowadays, if the infection is survived, the children may die of leukaemia. The second type of leuksemia in children ? rare and may be caused by irradiation in utero. Reports from several centres suggests that stalemate has been reached as far as the endocrine treatment of cancer is concerned. Enough large series of patients have been studied to provide a clear idea about the clinical usefulness of the various forms of such treatment, but there is still little direct experimental evidence concerning the mechanisms by which these affect the course of the disease. Emmens and his colleagues in Sydney report that the most potent antioestrogen so far found in their work is dimethyl stilboestrol and a clinical trial of the effectiveness of this compound in mastitis is in progress. The overall impression from the report is that there is no sign of a fundamental discovery which holds out any promise of a new era in the treatment of cancer. Rather, the impression is one of inching forward by vast. and painful effort. ACADEMIC CHANGES IN NEW ZEALAND
THE University of New Zealand is to disappear at the end of this year, and, in preparation for this honourable dissolution, it has already handed over its examining powers to its component institutions the University of Otago at Dunedin, the University of Canterbury, the Victoria University of Wellington, and the University of Auckland. The University of Auckland has been designated as the seat of New Zealand’s second medical school-there is already one at Dunedin-and Sir Douglas Robb, F.R.C.S., has been elected chancellor. As yet the Government has not authorised the launching of the school, but the university has lately set up a faculty of medicine to coordinate existing postgraduate facilities and to prepare the way. A steering committee has been studying the problem for over two years, and the Auckland Medical Research Foundation, set up in 1957, will be of great assistance. Mr. A. C. H. BELL has been re-elected president of the Royal College of Obstetricians and Gynxcologists.