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Geography literature is rife with calls for the protection of the integrity of the discipline with specific reference to the preservation of the space-in-time perspective, and calls for the discipline to start responding to the transformation imperative of the country are also abundant. Throughout the literature, jmphasis has thus far always been on the need for geographers to ensure that their skills and research are applied and are useful in promoting the transformaion process in South Africa. It is however our opinion that the relevance and contribution of the discipline have proven unquestionable, whilst the issue of possible costs or compromises that the discipline may have to endure as a result of ensuring “usefulness” is not always discussed. It is therefore argued in this aper that we as geographers need to pledge a commitment not only to protect the integrity of the discipline (space-in-time perspective) but also to ensure that our skills, knowledge and research are used in an accountabl...

1. Batches of Aëdes (Stegomyia) aegypti which had fed on monkeys in the early febrile stage of yellow fever and which has subsequently passed the usually accepted extrinsic incubation period for the virus, failed to transmit the disease to normal monkeys in approximately fifty per cent of the experiments. During the same time over eighty per cent of blood transfers were successful. 2. The monkeys which failed to show fever following mosquito bites later proved resistant to the inoculation of blood or tissues containing virus. 3. The incubation, or afebrile, period in monkeys following the bites of infected mosquitoes varied from less than twenty-four hours to fifteen days. It averaged somewhat longer in non-fatal than in fatal infections.

These experiments indicate that, although there are quantitative differences in virulence and minor differences in behavior, the African strain and the Brazilian strains of yellow fever virus tested are immunologically the same.

It would appear that inoculation of rhesus monkeys served a diagnostic purpose in one of our cases, that of S. R. The disease was so mild that in the absence of an epidemic no clinician would have made the diagnosis without this laboratory procedure. It should be pointed out that following inoculation of liver emulsion, and sometimes even of blood, it is impossible to tell whether an early fever resulting is due to a protein reaction, to bacterial infection, or to true yellow fever. If plenty of animals are available the only safe plan is to take blood for subinoculation and for cultures, and to feed mosquitoes. Blood may be kept frozen for some time before inoculation if it is found to be necessary, or if it is desired to await the outcome of the disease in the animal bled. A combined blood and liver transfer showed the presence of virus in rhesus No. 46 twenty days after the original inoculation with kidney from the autopsy in the case of J. V. 0. The same animal had had an infected body wall and a bacteriemia. On the basis of later experience we can see some of our mistakes. In the second S. R. passage (rhesus No. 133) blood transfer should have been made at the time of initial fever, the day following inoculation. In the case of rhesus No. 60, mosquito infection from J. V. 0., transfer probably should have been made when the temperature reached 103.9 degrees F. on the fifth day. Two days later, with a fever of 104.4 degrees F., the blood appeared to be non-infective. A temperature of 104 degrees F. in monkeys is usually a safe borderline between fever and no fever, but seemingly not always. Our experience with the South American viruses so far indicates that it takes much care, patience, and an abundance of monkeys to build up and maintain a high degree of virulence.

Yellow fever virus from M. rhesus has been inoculated into a South American monkey (Cebus macrocephalus) by blood injection and by bites of infected mosquitoes. The Cebus does not develop the clinical or pathological signs of yellow fever. Nevertheless, the virus persists in the Cebus for a time as shown by the typical symptoms and lesions which develop when the susceptible M. rhesus is inoculated from a Cebus by direct transfer of blood or by mosquito (A. aegypti) transmission.

1. Saimiri sciureus has been infected with yellow fever virus, both by the inoculation of infectious blood and by the bites of infective mosquitoes. Some of the monkeys have died, showing lesions, including hepatic necrosis, suggesting yellow fever as seen in human beings and in rhesus monkeys. Virus has been transferred back to M. rhesus from infected Saimiri both by blood inoculation and by mosquito bites. The virus undoubtedly has been maintained through four direct passages in Saimiri. Reinoculations of infectious material into recovered monkeys have not given rise to invasion of the blood stream by virus. Sera from recovered animals have protected M. rhesus against the inoculation of virus. 2. It has been possible to pass the virus to and from Ateleus ater by the injection of blood or liver and by the bites of mosquitoes. The livers from two infected animals have shown no necrosis. The serum from one recovered monkey proved to be protective for M. rhesus. 3. Only three out of twelve Lagothrix lagotricha have reacted to yellow fever virus by a rise in temperature. Probably none have died as a result of the infection. In only one instance has the virus been transferred back to M. rhesus. The sera of recovered animals have had a protective action against yellow fever virus.

Information provided by Queensland pathology laboratories shows that the annual incidence of cutaneous malignant melanoma in Queensland has doubled from 16 per 100 000 population in 1966, to 32.7 per 100 000 in 1977. The incidence in males, and the males to females ratio have increased. The major sites of the tumour remain the same, except possibly for a reduction in the number of leg tumours in females in tropical Queensland. More tumours with an in-situ component of Hutchinson's melanotic freckle type are being diagnosed. The tumours diagnosed in 1977, compared with those in the Queensland Melanoma Project files from 1963 to 1969, are more superficial (Level 1 or Level 2), with nonelevated profile and smaller diameter. The findings suggest that the disease is being diagnosed and treated earlier.

The results of treatment of 729 patients with cancer of the large bowel treated at the Princess Alexandra Hospital from January 1971 to December 1980 have been analysed. The majority (540 patients or 74.1%) presented with symptoms requiring investigation, and there was an incidence of acute obstruction of 17.6% (128 patients). In just over half the patients (55.3%) there was a significant delay in diagnosis. The operative mortality rate for curative resections for both rectal and colonic cancer was 2.7%. There was no mortality in 24 curative local resections for rectal cancer. The resection rate for the whole group was 87.4% and the age corrected 5-year survival rates were Dukes' A 99.1%; Dukes' B 78.3%; and Dukes' C 32.4%. These results are compared with those reported in a retrospective study from this Hospital in 1975 and with those from other Australian and overseas centres.

From 316 patients admitted to hospital, 329 pigmented skin lesions suspected of malignant melanoma were diagnosed by urgent frozen sections prepared in the cryostat. There were three groups: about one-half were malignant melanomas, and about one-quarter each were nevi and nonmelanocytic tumors, predominantly pigmented basal cell carcinomas and basal cell papillomas. Histologic error occurred in 4 cases (1.2%), and in 2 cases of combined nevi resulted in unnecessary surgery. The recognition of combined nevi is important in avoiding error; histologic guides are mentioned. The error rate is acceptable when compared with published rates of frozen section diagnoses on a wider range of tissues. The diagnosis was withheld in 19 lesions (5.8%); the causes were superficial level of the tumor, heavy lymphocytic infiltration, partial tumor regression, and unusual cell shape and arrangement in the melanomas. In the three groups the majority of lesions was less than 15 mm maximum diameter, and had no measurable height. Nearly 40% of the melanomas were Level I and II. Most of the nevi were compound, but an important group were combined nevi. Surgical excision was apparently excessive in 16 (5%) lesions. It is concluded that frozen section diagnosis of malignant melanoma in experienced hands is reliable and is of considerable value to the surgeon.

Tests for the presence of oncornavirus-like particles in human biopsies were made by the Spiegelman simultaneous assay for 70S RNA and RNA-dependent DNA polymerase and by detection of 600–900S particles, incorporating 3H-uridine, produced by cultured biopsy cells. Thirty-one malignant melanoma biopsies from 29 patients were studied. Using the simultaneous assay, evidence of virus-like particles was found in 15/26 (58%) of melanoma biopsies, 0/3 naevi pool, 1/4 samples of skin adjacent to melanoma, 0/3 samples of normal adult skin and 0/3 prepuces. The velocity sedimentation technique was shown to be a useful screening test for oncornaviruses in studies of two virus-producing mouse cell lines (TKL-5 and WEHI-22), and was positive with 7/9 melanoma biopsies. Overall, these results are compatible with the earlier findings of similar virus-like particles in malignant melanoma cell lines, but the exact nature of the particles remains to be defined. Particules Du Type Oncornavirus Dans Des Biopsies De Cas De Melanome Malin Et De Temoins Les auteurs ont recherche la presence de particules du type oncornavirus dans des biopsies humaines au moyen de l'epreuve simultanee de Spiegelman pour l'ARN 70S et l'ADN polymerase ARN-dependante et de la detection des particules 600–900S, qui incorporent l'uridine tritiee et que produisent les cellules de biopsie en culture. Trente et une biopsies de melanome malin provenant de 29 malades ont ete etudiees. Avec l'epreuve simultanee, on a constate la presence de particules de type viral dand 15/16 biopsies de melanome (58%) et 1/4 echantillons de peau adjacente au melanome; les 3 pools de naevi, les 3 echantillons de peau normale d'adulte et les 3 echantillons de prepuce n'en contenaient pas. La technique de sedimentation rapide constitue une epreuve valable de detection des oncornavirus, comme l'ont revele les etudes portant sur deux lignees de cellules murines productrices de virus (TKL-5 et WEHI-22); elle a ete positive pour 7/9 biopsies de melanome. Dans l'ensemble, ces resultats sont compatibles avec les constatations precedentes, selon lesquelles on trouve des particules analogues dans les lignees de cellules de melanome malin, mais la nature exacte de ces particules reste a definir.

Cases of carcinoma of the rectum have been prospectively studied from 1971-80. Two hundred and ten patients had curative resections and 25 of these developed clinical pelvic recurrence in the period of follow-up which ranges from one to eleven years. The rate of recurrence is found to be dependent on the level of the lesion and the degree of its local and lymphatic spread. Results from other papers are discussed. Measures to minimise local recurrence are discussed.

An unselected prospective consecutive series of 575 patients with a single adenocarcinoma of the colon and of 331 patients with a single adenocarcinoma of the rectum registered between 1971 and 1984 at the Princess Alexandra Hospital is reported. The tumours were staged according to the Australian Clinicopathological Staging (ACPS) System. Approximately one-quarter of the patients were incurable when they presented. For curative operations for carcinoma of the colon, the operative mortality was 3%. For curative operations for carcinoma of the rectum, the operative mortality was 1% for abdominoperineal resection and 4.5% for anterior resection. The relative 5 year survival for all patients was 54.5%. The findings are compared with other large Australian series as well as with series from the United Kingdom and the United States.

Summary and Conclusions During the course of three experiments undertaken to test the flight of Stegomyia aegypti, in which over 20,000 stained specimens were released in small villages, two specimens were recovered in houses at a distance of more than 300 meters from the point of release, while 95 were taken at intermediate points. Another lot of 12,000 mosquitoes was released on a boat 900 meters distant from one shore and 300 meters from the opposite shore. Of these, eight were recovered on shore at an approximate distance of one kilometer from the boat. Less than 0.4 per cent of the entire number of released mosquitoes was recovered. The latest capture made was thirteen days after the date of release (experiment I). After a week's time all stained specimens became exceedingly scarce. This indicates either that dispersion is very thorough, widespread, and rapid, or that mortality is very high. From the foregoing, it would appear that a flight of more than 300 meters is not exceptional among the stegomyiae of a representative community; and a sustained flight of one kilometer over water is well within the range of possibility.

The 'Cambrian explosion' refers to the major adaptive radiation of the metazoans during the earliest Phanerozoic, an event that is best known by the abrupt appearance of hard parts near to the Precambrian–Cambrian boundary (˜550 Myr BP)1. Deciphering this important evolutionary episode depends largely on the study of these skeletal remains2,3, together with trace fossils that include burrows and trackways4,5. Many of these latter fossils evidently represent the activities of soft-bodied organisms, such as worms and lightly sclerotized arthropods, whose exact identity is seldom known, not least because they can be fossilized only in exceptional circumstances6. However, documenting the soft-bodied representatives of early metazoan communities cannot be neglected if they accounted for a substantial fraction of these early biotas7. Here we report a new soft-bodied fauna from the Lower Cambrian of North Greenland. This assemblage has highly significant similarities with the younger Burgess Shale, and provides additional evidence for the geological longevity of this faunal type and its widespread distribution in deeper waters of Cambrian oceans.

Summary In Franca, Brazil, Anopheles darlingi Root was found to be transmitting malaria. The predominating mosquito from breeding areas was A. albitarsis. The only Anopheles caught in houses was darlingi. In 240 dissections of the latter species, there were encountered 69 infections with malaria parasites. Among 215 salivary glands examined, 16, or 7.4 per cent, showed sporozoites.

Concentrations of the third component of complement (C3, β1C globulin) in serum may vary considerably in patients with certain diseases. Its accurate measurement is therefore important medically. For some time it has been recognized that the C3 in serum stored at room temperature breaks down into two proteins, β1A and α2D. Monospecific antisera have been made to the three antigenic determinants of C3, designated A, B, and D. An anti-C3 supplied commercially is monospecific for the A determinant, which is shared by C3 and its breakdown product β1A. With C3 breakdown and formation of β1A, depletion of antibody to the A determinant is increased to 1.6 times the depletion by native C3. Therefore, the previous history of a serum can affect the "apparent" concentration of C3, with values spuriously increased to a variable degree, in serum that has been stored. The effect of time, temperature, and conditions of storage on this increase are discussed.

Blood samples were obtained from hosptial patients suspected of having cancer (colorectal carcinoma, breast carcinoma, or melanoma) or from patients after surgical treatment for these cancers. Leukocytes were tested for reactivity with appropriate tumor extracts by leukocyte adherence inhibition (LAI), without knowledge of the diagnosis. Leukocytes from each patient were tested with the specific related extract corresponding to the suspected tumor type and with at least one unrelated extract. Each patient's serum was tested for its effect on the adherence of autologous leukocytes with specific tumor extract. Detailed leukocyte adherence data are presented for each of the 110 patients. Of the 75 patients eventually diagnosed as having cancer of one of the above types, 67 (89.3%) gave positive specific LAI reactions and only 5 (6.7%) reacted nonspecifically. Of the 35 patients with benign, unrelated, or unidentified disease, 10 (28.6%) gave positive reactions; most of these were patients with benign breast disease reacting with breast tumor extract. Leukocyte reactions with related extracts were almost always blocked by autologous serum (only two exceptions). When tested with allogeneic leukocytes reacting with their corresponding extracts, sera never blocked leukocytes of a different tumor type; in some cases they also failed to block leukocytes of the same tumor type although autologous leukocytes were blocked.

The mortality and complications of large-bowel resection for carcinoma performed at the Princess Alexandra Hospital since the Colorectal Project commenced in 1971 are reviewed and compared with the results in other published series. There were 443 patients in this prospective study, and 375 underwent resection of their tumour. The overall operative mortality was 6.4% - for colonic lesions it was 8.0% and for rectal 3.4%. The mortality for elective curative resections was 2.6%, and for emergency resections it was 10.8%. The anastomotic leak rate was 6.8%, but was higher (16.6%) when the anastomosis was done at the time of emergency resection. No patient whose anastomosis leaked but who had had a previous defunctioning proximal colostomy died. There was a wound infection rate of 15.1%.

The leukocyte adherence inhibition technique was used to assess cell-mediated immunoreactivity and serum-blocking factors related to adenocarcinoma of the colon or rectum. In the group of 48 patients with confirmed tumors of this type, 36 of 38 had reactive leukocytes and 46 of 47 had serum-blocking factors. Patients whose tumors had been removed surgically, with no sign of recurrence, retained their leukocyte activity for up to 3.5 years in 6 of 6 cases, but only a small proportion (7 of 30) retained blocking factors. In 67 controls (who were patients with nonmalignant gastrointestinal disorders, patients with gastrointestinal tumors other than colorectal adenocarcinoma, patients with other cancers, or healthy volunteers), negative reactions were obtained, with diverticular disease the only prominent exception. The leukocyte adherence inhibition test appeared to be highly sensitive and specific. Application to the immunodiagnosis of colorectal cancer thus seems to be warranted.

The prognosis of melanoma is no longer hopeless. It can be diagnosed at an early biological stage when simple surgical excision is curative. Public and professional education is necessary to achieve and maintain the successful management of this potentially dangerous tumour.

Of 1,444 patients with primary cutaneous melanomas, 57 (3.9%) developed more than one. Most had two primary lesions but one had six. Every effort was made to insure that all melanomas were primary tumors. Most patients developed new primary melanonas within five years of the original operation, but an appreciable number developed them many years later. In the largest group, second and subsequent primary tumors developed in different areas of the body at later times. The subsequent tumors were not diagnosed at an earlier biological stage than the original tumors. Patients with primary cutaneous melanoma should be made aware of increased risk of developing another primary melanoma and physicians should do careful examinations for new primary melanomas as well as for recurrences of the original melanoma.

The first published account of a patient with melanoma — a secondary deposit with no known primary — was reported by John Hunter in 1787, although Hunter never described the disease as such. The original specimen is preserved in the Hunterian Museum of the Royal College of Surgeons of England. In 1820, William Norris, of Stourbridge, England, described the first case of melanoma in the English literature1. It was of a patient who died of disseminated melanoma. Norris was a pioneer in the understanding of melanoma2. Among other things, he was the first to report local recurrence following minimal excision; the first to advocate wide excision of the tumour and surrounding tissues; the first to note that neither medical nor surgical treatment was effective when the disease was widely disseminated; and the first to record melanoma in a family. Sir Jonathan Hutchinson described subungual melanoma in 1857 and later illustrated in 1892 and 1894 a series of cases, to which the title “Hutchinson’s Melanotic Freckle” was applied. Sampson Handley, in 1907, advocated wide local excision and regional node dissection on the basis of an autopsy of a single patient with a very advanced melanoma.

During a follow-up period of six to 12 years, 15.4% of patients in the Queensland Melanoma Project (Q.M.P.) developed histologically proven secondary deposits in lymph nodes. The incidence rate in males (21%) was twice that in females (11%), but the mortality rate was similar (M., 67%; F., 61%). Thirty-two patients (2%) had positive nodes with no known primary lesion. Metastases developed in males with lesions on the foot (50%), on the thigh (29%), and on the back (22%); and in females with lesions on the lower leg (9%) and thigh (20%). About one-half of the nodes were removed at the time of treatment of the primary growth or within two months. Three-quarters were removed in the first year. However, it was found that tumour could remain dormant for more than eight years. Dormant tumours behaved in a similar aggressive fashion on regrowth as non-dormant secondaries. Nodal metastases were present in 5% of patients at the time of their first presentation with primary melanoma. Elective node dissections were done in 6% of males and 11% of females.

Studies of immunoglobulin levels in middle ear fluid in children with chronic otitis media show that MEF (middle ear fluid) IgA levels are proportionately higher than serum levels. Disproportionately elevated MEF IgA levels may be due to secretory IgA. Finding secretory IgA in MEF suggests the presence of a secretory epithelium and may define the etiology of chronic inflammation. Resolution of the secretory epithelium may be hastened with adequate ventilation of the middle ear space.

In a prospective series of 443 cases of large-bowel cancer there were 192 cases occurring in patients aged 70 years and over. The resectability rate in this group was 84.9% and was almost identical with that of the whole series (84.6%). There was an overall operative mortality rate of 7.3% in the older age group, compared with 6.4% in the whole series. However, when octogenarians were considered, the resectability rate fell to 74.6% and the overall operative mortality rate increased to 19%. In the treatment of large-bowel cancer it would seem that special consideration should be given to octogenarians.

The consumption of polyunsaturated fats of patients with malignant melanoma and of a control group of patients with benign naevi has been compared in order to determine whether polyunsaturated fats predispose to the development of malignant melanoma. Patients with malignant melanoma had not consumed excessive quantities of polyunsaturated fats. Thus, there was no evidence to indicate that ingestion of polyunsaturated fats is associated with an increase in incidence of melanoma.

During the reaction of an immune precipitate with fresh human serum, C3 undergoes a number of molecular alterations with the formation of conversion products differing from those obtained when purified components react. Those products which remain in the fluid phase, the subject of the present paper, have been identified by their reaction with monospecific antisera to the three antigenic determinants of C3, A, B, and D, after electrophoresis in agar or polyacrylamide gel. When purified C3 reacts with EAC1,4,2, C3i is found in the fluid phase. C3i, a loose complex of C3a and C3b, is in a conformational state whereby only the A and D antigens, present on its C3b portion, will consume antibody. The B antigen, present on the C3a portion of C3i, is unavailable for combination with antibody until C3i dissociates. In the fluid phase of the reaction of an immune precipitate with whole serum, C3i, C3a, and C3b, formed when purified components react, cannot be found. Instead the end products of the reaction appear to be C3c, which contains the A antigen, and C3d, which contains the D antigen. C3c and C3d are similar to the beta1A and alpha2D produced by the aging of serum but differ in their mobilities in acrylamide gel and in agar. The C3c and C3d generated by an immune precipitate also differ slightly from the C3c and C3d produced by the reaction of trypsin with C3 in whole human serum. As human serum reacts with an immune complex, native C3 appears to undergo a primary alteration before conversion. This alteration results in a molecular species of C3 which is labile at 56 degrees C for 30 min, fails to expose additional A and D antigenic sites upon aging, and which forms beta1A and C3d rather than beta1A and alpha2D during aging. In addition to this altered form of native C3, a new conversion product, C3x, is formed as whole serum reacts with an immune complex. C3x is not found in systems utilizing pure complement components. C3x is like C3 in that it bears all three antigenic determinants but differs in that it has a slightly faster mobility in polyacrylamide gel than does native C3. C3x is not only found in the fluid phase but is also bound to the immune precipitate. Finally, the fluid-phase kinetics of each of the antigens of C3 have been determined as normal human serum reacts with an immune precipitate. These illustrate that nearly the entire population of native C3 molecules undergoes conversion rapidly as manifested by the disappearance of the B antigen from the fluid phase. Moreover, the kinetics of the fluid-phase A and D antigens reflect that the conversion of C3 in serum is quantitatively not the same as when purified C3 reacts with C4,2.

Evidence has been obtained for the presence in vivo of alpha(2D)-globulin, a breakdown product of serum beta(1C)-globulin, in patients with acute and persistent hypocomplementemic glomerulonephritis. The protein has been identified by immunoelectrophoretic analysis, and the amounts present have been determined by direct measurement of specific antigenic determinants present on alpha(2D). beta(1A)-Globulin, another breakdown product of beta(1C)-globulin, may also be present in vivo in severely hypocomplementemic patients, but its levels are much lower than those of alpha(2D)-globulin.Alpha(2D)-globulin has been identified by immunoelectrophoretic analysis of fresh EDTA plasma from patients with hypocomplementemic nephritis as an arc in the alpha(2) region that shows a reaction of identity with the arc representing alpha(2D)-globulin produced by aged normal serum. beta(1A)-Globulin was not seen in these patterns. Measurement of specific antigenic determinants has been carried out in both fresh EDTA plasma and aged serum. In the fresh plasma, the concentration of D antigen, found on both beta(1C)- and alpha(2D)-globulins, has been related to that of B antigen, found only on beta(1C) and taken as a measure of the concentration of this protein. In the hypocomplementemic patients, the concentration of D antigen, in comparison to that of B, was greater than in the normal subjects. Similarly, in aged serum, the level of alpha(2D) was greater than would be expected from the amount of beta(1C) that had been broken down in vitro, measured by the concentration of beta(1A). Calculations indicated that the in vivo alpha(2D) level in severely hypocomplementemic patients ranged from 7.5 to 18% of that which would be found in a pool of aged normal serum in which beta(1C) is completely broken down. The levels tended to be lower in less severely hypocomplementemic patients, and none could be detected in normal plasma. Only small quantities of A and D antigens are detectable in the urine of patients with hypocomplementemic nephritis. The rate of excretion is about equal to that of the normal subject. The study indicates that the low serum levels of beta(1C)-globulin that may be present over long periods in patients with persistent hypocomplementemic glomerulonephritis can be ascribed, in part, to in vivo breakdown of this protein as a result of reaction with immune complexes. The contribution of beta(1C) deposition on immune complexes and of diminished synthesis to the depressed serum levels cannot be assessed by the present study.