55 research outputs found
An Unusual Case of Human Rabies Thought to be of Chiropteran Origin
On 21 February 1970 a White male patient died in the H. F. Verwoerd Hospital, Pretoria after a 5-day illness diagnosed clinically as rabies. The source of exposure to the disease was reported to be a bat bite sustained approximately 5 weeks earlier. Fluorescent antibody (FA) tests using standard conjugate on the deceased's brain were negative but Negri bodies were found histologically in the Purkinje cells of the cerebellum. A strain of rabies virus not demonstrable with standard FA conjugate was isolated from brain tissue. Specific FA conjugate prepared from this virus revealed the presence of typical rabies fluorescent inclusions in the brain of the deceased
Rabies in bat-eared foxes in South Africa
Rabies in bat-eared foxes was first recognized in South Africa in 1955 and is likely to have been derived
from canine rabies introduced to South Africa in 1950. Since then it has become established in this
species in the drier western half of the country and the south-western Cape so that rabies now occurs
in bat-eared foxes adjacent to the peri-urban canine population of Cape Town. Peak incidence was
recorded in the early 1980s and the incidence is seasonal with most cases occurring in winter.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201
Canid and viverrid rabies viruses in South Africa
Historical records suggest that in South Africa rabies was present in viverrids in the early 1800s. In
the early 1950s a wave of canine rabies spread from Namibia through Botswana into the northern Transvaal
and by 1961 a second front had penetrated south from Mozambique into Swaziland and northern
Natal. Today, rabies is regularly confirmed in a number of canid and viverrid species in most regions
of South Africa. A panel of anti-nucleoprotein monoclonal antibodies was used to examine 83 virus
isolates from these species. Two major reaction patterns, one chiefly confined to viruses from canids
and the other to viruses from viverrids, were obtained. In addition, some variation in the reaction patterns
of viverrid viruses was observed and spill-over of viverrid virus into canids and vice versa was recorded.
Rabies in South Africa appears to behave as two distinct disease entities.Proceedings of a workshop held at the Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa, 3-5 May 1993The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201
Performance of Lotus corniculatus L. genotypes submitted to cutting interval: subsidies to a breeding program
The objective of this work was to evaluate the response of five birdsfoot trefoil populations (Lotus corniculatus L.), selected under severe and intense grazing (P38, P37, P9 and P3) or cutting (population Corte), one rhizomatous population from Morocco and two cultivars, São Gabriel (Brazil) and ARS 2620 (USA), to different cutting intervals (20 and 40 days). The trial was carried out in a greenhouse for 224 days. The plants were submitted to the treatments during four months, when it was made four and two cuttings for the 20 and 40 day intervals, respectively. In the following months, aerial part of the plants was totally removed and after 70 days of regrowth, evaluation of roots and aerial section were performed. Analysis of variance and multivariate analysis was performed, obtaining the Mahalanobis distance (Md), dendogram by UPGMA method and the relative contribution of the characters for genetic divergence. There was no genotype × cutting interval interaction and the genotypes presented a reduction on dry matter yield of roots, crown and aerial sections, number of stems and plant height when submitted to frequent cuttings. The most divergent genotypes were Marrocos and P9 (Md = 108.7) and the most similar ones were São Gabriel and P37 (Md = 7.8). The results suggest exclusion of the population P9 because of its weak performance and the utilization of the populations Corte and P37 as progenitors in the birdsfoot trefoil breeding program. Root dry matter accumulation and plant height were the characters that contributed most to genetic divergence and they can be used for selection works
The suitability of a rolled BHK₂₁monolayer system for the production of vaccines against the SAT types of foot-and-mouth disease virus. I. Adaptation of virus isolates to the system, immunogen yields achieved and assessment of subtype cross reactivity
In an examination of 34 southern African SAT-type foot-and-mouth disease viruses, all but 1 attained satisfactory levels of infectivity within 6 passages in rolled BHK₂₁monolayer cell cultures. However, there were marked differences between adapted viruses with respect to the mass of immunogen (146S material) produced. Several isolates which consistently produced levels ≥2 µg/ml were identified. In cross neutralization tests using post-vaccinal sera, SAT-1 and SAT-2 isolates showed considerable diversity and none of the viruses tested would be expected to produce a broad-spectrum response if incorporated into a vaccine. On the other hand, when 2 of the SAT-2 isolates were incorporated into the same vaccine a distinctly broader response resulted.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201
Confirmation of the occurrence of a second killer whale morphotype in South African waters
Killer whales Orcinus orca occur worldwide in a number of morphotypes that differ in size, pigmentation, acoustic
behaviour, food type and genetics – some may indeed warrant subspecific or even specific status. Until recently, all
killer whales in South African waters were referred to a single morphotype, Type A, but three individuals (two males
and one female) that have stranded since 1969 differ in several respects from other killer whales examined from
the region. Adult length is some 1–1.5 m smaller, appendages such as dorsal fin and flippers tend to be relatively
larger, and tooth wear is excessive. Although dietary information is scant, one stomach contained the remains of
several elasmobranchs, identified from a DNA subsample as blue sharks Prionace glauca, a dietary item that, if
habitual, might account for the tooth wear. This morphotype, referred to here as ‘flat-toothed’ and which in several
respects resembles the offshore form in the North Pacific and the Type 1 form in the North Atlantic, does not seem
to have been recorded previously from the Southern Hemisphere.National Research Foundation, South Africahttp://www.tandfonline.com/loi/tams20hb201
Rabies in southern Africa
The first confirmed outbreak of rabies in Africa, believed to have followed the importation of an infected
dog from England in 1892, occurred in the eastern Cape Province of South Africa, and was brought under
control in 1894. An unconfirmed epidemic of rabies in dogs occurred in western Zambia in 1901. By the
following year the disease had apparently spread along a major trade route, to cause an outbreak in
Zimbabwe which engulfed most of the country before being eradicated in 1913. The existence of endemic
rabies of viverrids (mongooses and genets) was confirmed in South Africa in 1928, and since then the
viverrid disease has continued to occur widely on the interior plateau of the country with spill-over of
infection to cattle and a variety of other animals. From about 1947 onwards, an invasive form of dog
rabies spread from southern Zambia and/or Angola into Namibia, across northern and eastern Botswana
into Zimbabwe and the northern Transvaal by 1950, entered Mozambique in 1952, and spread from there
to Swaziland in 1954. Dog rabies extended from southern Mozambique into Natal in 1961 to cause a
major epidemic which was brought under control in 1968. The disease re-entered northern Natal from
Mozambique in 1976 and since then dog rabies has proved difficult to control in the peri-urban settlements
of Natal-KwaZulu. The disease spread from Natal to Lesotho in 1982, and into the Transkei region of the
eastern Cape Province in 1987, to reach the Ciskei by 1990. The spread of the disease in dogs was
followed by the emergence of rabies of jackals and cattle in central Namibia, northern Botswana, Zimbabwe
and the northern Transvaal. A unique outbreak of rabies in kudu antelope occurred in central Namibia
from 1977 to 1985, apparently involving oral spread of infection between individuals. A few cases of rabies
in the bat-eared fox were recognized each year in Namibia from 1967 onwards, and from the 1970s the
occurrence of the disease in the fox has emerged as a distinct problem in the northern Cape Province
and spread to the west coast. The rabies-related viruses, Lagos bat, Mokola and Duvenhage, associated
with bats, shrews and rodents in Africa, are known to have caused isolated cases of disease in South Africa,
and on one occasion a small outbreak involving six cats and a dog in Bulawayo, Zimbabwe. However,
the results of monoclonal antibody tests on numerous specimens indicate that the rabies-related
viruses are not a major cause of disease in southern Africa.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn2014mn201
Tomato: a crop species amenable to improvement by cellular and molecular methods
Tomato is a crop plant with a relatively small DNA content per haploid genome and a well developed genetics. Plant regeneration from explants and protoplasts is feasable which led to the development of efficient transformation procedures.
In view of the current data, the isolation of useful mutants at the cellular level probably will be of limited value in the genetic improvement of tomato. Protoplast fusion may lead to novel combinations of organelle and nuclear DNA (cybrids), whereas this technique also provides a means of introducing genetic information from alien species into tomato. Important developments have come from molecular approaches. Following the construction of an RFLP map, these RFLP markers can be used in tomato to tag quantitative traits bred in from related species. Both RFLP's and transposons are in the process of being used to clone desired genes for which no gene products are known. Cloned genes can be introduced and potentially improve specific properties of tomato especially those controlled by single genes. Recent results suggest that, in principle, phenotypic mutants can be created for cloned and characterized genes and will prove their value in further improving the cultivated tomato.
Detectable clonal mosaicism and its relationship to aging and cancer
In an analysis of 31,717 cancer cases and 26,136 cancer-free controls from 13 genome-wide association studies, we observed large chromosomal abnormalities in a subset of clones in DNA obtained from blood or buccal samples. We observed mosaic abnormalities, either aneuploidy or copy-neutral loss of heterozygosity, of >2 Mb in size in autosomes of 517 individuals (0.89%), with abnormal cell proportions of between 7% and 95%. In cancer-free individuals, frequency increased with age, from 0.23% under 50 years to 1.91% between 75 and 79 years (P = 4.8 × 10(-8)). Mosaic abnormalities were more frequent in individuals with solid tumors (0.97% versus 0.74% in cancer-free individuals; odds ratio (OR) = 1.25; P = 0.016), with stronger association with cases who had DNA collected before diagnosis or treatment (OR = 1.45; P = 0.0005). Detectable mosaicism was also more common in individuals for whom DNA was collected at least 1 year before diagnosis with leukemia compared to cancer-free individuals (OR = 35.4; P = 3.8 × 10(-11)). These findings underscore the time-dependent nature of somatic events in the etiology of cancer and potentially other late-onset diseases
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