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1.
To investigate the molecular epidemiology of Cryptosporidium species in children in Australia, fecal specimens from 50 Australian children with gastrointestinal symptoms and seven isolates from Australian neonatal dairy calves were genotyped and sub-genotyped at the 18S rDNA and GP60 loci, respectively, and compared with human and animal isolates collected from Europe, the US and Canada (n=35). Results revealed that the majority of the Australian human isolates were infected with C. hominis (41/50), while the remainder were infected with C. parvum. All the Australian cattle as well as cattle from US, Canada, UK and Switzerland were infected with C. parvum. Subtyping of 92 Cryptosporidium isolates at the GP60 locus identified seven subtype families of which six were identified in Australian isolates; four C. hominis subtypes and two C. parvum subtypes. Results suggest that although transmission is largely anthroponotic in Australia, cattle may be a source of sporadic human infections.  相似文献   

2.
The smooth optical surface of the cornea is maintained by a tear film, which adheres to a variety of microprojections. These microprojections increase the cell surface area and are thought to improve the movement of oxygen, nutrients, and metabolic products across the outer cell membranes. However, little is known of these structural adaptations in vertebrates inhabiting different environments. This field emission scanning electron microscopic study examined the cell density and surface structure of corneal epithelial cells across 51 representative species of all vertebrate classes from a large range of habitats (aquatic, amphibious, terrestrial, and aerial). In particular, we wished to extend the range of vertebrates to include agnathans and some uniquely Australian species, such as the Australian lungfish (Neoceratodus forsteri), the Australian galah (Eolophus roseicapillus), the Australian koala (Phascolarctos cinereus), and the rat-tailed dunnart (Sminthopsis crassicaudata). Epithelial cell densities ranged from 28,860 +/- 9,214 cells mm(-2) in the flathead sole Hippoglossoides elassodon (a marine teleost) to 2,126 +/- 713 cells mm(-2) in the Australian koala (a terrestrial mammal), which may indicate a reduction in osmotic stress across the corneal surface. A similar reduction in cell density occurred from marine to estuarine to freshwater species. The structure and occurrence of microholes, microplicae, microridges, and microvilli are also described with respect to the demands placed on the cornea in different environments. All species that spend significant periods out of an aquatic environment possess microvilli and/or microplicae. These include all of our species of Mammalia, Aves, Reptilia, Amphibia, and even one species of Teleostei (Australian lungfish). Well-developed microridges occur only in teleosts in high osmolarity environments such as marine or estuarine habitats. Clear interspecific differences in corneal surface structure suggest a degree of adaptive plasticity, in addition to some phylogenetic trends.  相似文献   

3.
Abnormal, uncoordinated swarming motility of the opportunistic human pathogen Proteus mirabilis was seen when a crude extract of the Australian red alga Delisea pulchra was added to the medium. This occurred at concentrations at which growth rate, swimming motility, cell elongation, polynucleation, and hyperflagellation were not affected. One halogenated furanone from D. pulchra inhibited swarming motility at concentrations that did not affect growth rate and swimming motility. Other structurally similar D. pulchra furanones had no effect on swarming, suggesting considerable specificity in the effects of furanones on swarming motility by P. mirabilis.  相似文献   

4.
Summary Probes of uncloned Bkm satellite DNA and a Drosophila clone 2(8), consisting mainly of GATA repeasts related to a major sequence component in Bkm, have been used to probe Southern blots of human male and female DNAs obtained from a Caucasian and an Australian aboriginal population and to human chromosomes in situ. Hybridization was observed to a distinct and an indistint series of bands against a smeared background. The same distinct bands are identified in the DNA samples with both probes, but are most readily detected using the uncloned Bkm probe. Most restriction bands are common to both populations and some are polymorphic. However, certain bands appear to be characteristic of the Australian aboriginal samples. There are no distinct sex-linked patterns. However all of the small acrocentric human chromosomes, including the Y chromosome show hybridization to uncloned Bkm in situ.  相似文献   

5.
Genetic susceptibility to pre-eclampsia and chromosome 7q36   总被引:4,自引:0,他引:4  
Pre-eclampsia is the most common serious medical disorder of human pregnancy. The human endothelial cell nitric oxide synthase (eNOS) gene is a candidate for pre-eclampsia/eclampsia (PE/E) susceptibility. A linkage study was performed on Australian PE/E families using 25 microsatellite markers from chromosome 7, one of which (eNOS-CA) resides within the eNOS gene. No significant linkage was found for the eNOS-CA marker using either parametric or non-parametric analysis. However, D7S 1805 from the eNOS gene region on 7q36, gave a suggestion of linkage using parametric analysis (maximum LOD score =2.143 at theta=0.14) and non-parametric APM analysis (T1/sqrt(p)=3.53; P=0.002). Further, an association study was performed on unrelated PE/E cases and controls from both Chinese and Australian populations to test for a relationship between the eNOS gene and PE/E. No association was found between the eNOS-CA marker and PE/E in either population. However, there was a significant difference in the allelic distribution of eNOS-CA between the two ethnic groups. The linkage results support the possibility that a susceptibility locus for pre-eclampsia resides in the 7q36 region, however, there is no definitive evidence to support the notion that the eNOS gene itself is responsible for susceptibility to pre-eclampsia.  相似文献   

6.
The Australian Federal Government has announced a two‐year trial scheme to compensate living organ donors. The compensation will be the equivalent of six weeks paid leave at the rate of the national minimum wage. In this article I analyse the ethics of compensating living organ donors taking the Australian scheme as a reference point. Considering the long waiting lists for organ transplantations and the related costs on the healthcare system of treating patients waiting for an organ, the 1.3 million AUD the Australian Government has committed might represent a very worthwhile investment. I argue that a scheme like the Australian one is sufficiently well designed to avoid all the ethical problems traditionally associated with attaching a monetary value to the human body or to parts of it, namely commodification, inducement, exploitation, and equality issues. Therefore, I suggest that the Australian scheme, if cost‐effective, should represent a model for other countries to follow. Nonetheless, although I endorse this scheme, I will also argue that this kind of scheme raises issues of justice in regard to the distribution of organs. Thus, I propose that other policies would be needed to supplement the scheme in order to guarantee not only a higher number of organs available, but also a fair distribution.  相似文献   

7.
At least two polymorphic Alu insertions have been previously identified and characterized within the class I region of the major histocompatibility complex (MHC). We have identified another two new polymorphic Alu insertions, AluyHJ and AluyHF, located near HLA-J and HLA-F, respectively, within the a block of the MHC. Here we report on (1) the haplotypic relationships between the Alu dimorphisms and the HLA-A locus within a panel of 51 IHW homozygous cell lines representing at least 36 HLA class I haplotypes, (2) the Alu genotype, allele, and haplotype frequencies present in the Australian Caucasians and Japanese populations, and (3) the frequency of association between the different Alu dimorphisms and the HLA-A alleles in 109 Australian Caucasians and 99 Japanese. PCR was used to detect the presence or absence of insertion for AluyHJ, AluyHG, and AluyHF within the DNA samples prepared from the cell lines and the two population groups that had been previously typed for HLA-A. In the homozygous cell lines, all three Alu insertions were found in only one HLA class I haplotype (HLA-A1, -B57, -Cw6), no Alu insertions were detected in six HLA class I haplotypes and one or more of the Alu insertions were found in 29 HLA class I haplotypes. At least one of the Alu insertions was found in about 86% of the Japanese and Australian individuals, with the AluyHJ generally related inversely to AluyHG and/or AluyHF. The gene frequency of the AluyHJ and AluyHF insertions was significantly different (p <0.05) BETWEEN JAPANESE AND AUSTRALIANS, WHEREAS THERE WAS NO DIFFERENCE (P > 0.05) between the frequencies of AluyHG in the two populations. The Alu haplotype frequencies were also significantly different between the Japanese and the Australians. In the cell lines and the population groups, the AluyHJ insertion was most frequently found associated with HLA-A1 or A24, AluyHG with HLA-A2, and AluyHF with HLA-A2, -A10, or -A26. This study suggests that the three polymorphic Alu elements have been inserted into the a block of the MHC in different progenitor groups and therefore will be useful lineage and linkage markers in human population studies and for elucidating the evolution of HLA class I haplotypes.  相似文献   

8.
Previous studies have shown that isolates of Chattonella marina from Australia and Japan exhibit differences in tolerance to high intensities of visible light. Here we show that the Australian strain of C. marina produces around five times more UV-absorbing mycosporine amino acids (MAAs) than the Japanese strain. This corresponds with 66% increased growth by the Australian strain under UVB exposure compared to no UV exposure. The MAA mycosporine-glycine, which reportedly acts as an antioxidant, was found in high quantity (110 fg cell-1) in the Australian but was absent in the Japanese strain. In contrast, changes in the concentration of violaxanthin and zeaxanthin per cell were 4.7-4.8 times greater in the Japanese relative to the Australian strain suggesting that the Japanese strain uses a xanthophyll cycle to moderate inhibition by high photosynthetically active radiation (PAR) irradiance. Increased MAA production under high irradiance was also observed in other Australian strains of Chattonella, but not noted in other Japanese strains suggesting ecophenotypic adaptation due to differing environmental conditions.  相似文献   

9.
While cloning, stem cells, and regenerative medicine are often imagined in a futurial idiom--as expectations, hype, hope and promises--this article approaches the remaking of genealogy in such contexts from a historical route. Through a series of somewhat disparate historical connections linking Australian sheep to the development of clinical IVF and the cloning of Dolly at the Roslin Institute in Scotland in 1996, this article explores the linkages through which agriculture, embryology, and reproductive biomedicine are thickly intertwined. Key to this examination is not only the history of experimental sheep breeding, and its somewhat unexpectedly genealogical connections to (Australian) national identity ('wool in the veins'), but also the re-emergence of a distinctive frontier ethos in the context of assisted conception, and later human embryonic stem cell derivation. I have set this scene of genealogical interconnection against the criss-crossing traffic between Britain and Australia, and the wool trade, to emphasise the importance of global, as well as local, connections in the bloodlines of animals such as Dolly. In sum, this article examines the idea of the 'biological frontier' by exploring its histories as a means to offset the assumption that this frequently encountered idiom describes a future that is, or must be, by definition, unknown and unknowable.  相似文献   

10.
Fifteen Australian macrofungi were investigated for cytotoxic activity. Ethanol, cold and hot water extracts of each species were screened for cytotoxic activity against normal mouse fibroblast cells (NIH/3T3), healthy human epithelial kidney cells (HEK-293), four cancer cell lines, gastric adenocarcinoma cells (AGS), two mammary gland adenocarcinoma cells (MDA-MB-231, MCF7) and colorectal adenocarcinoma cells (HT-29) with a validated MTT assay. Most extracts derived from Omphalotus nidiformis, Cordyceps cranstounii and Cordyceps gunnii demonstrated significant cytotoxic activity toward a variety of cancer cell lines. In contrast only some extracts from Coprinus comatus, Cordyceps hawkesii, Hypholoma fasciculare, Lepista nuda, Leratiomyces ceres and Ophiocordyceps robertsii displayed significant cytotoxic activity, which was usually selective for only one or two cancer cell lines tested. The least cytotoxic species evaluated in this study were Agaricus bitorquis, Coprinopsis atrametaria, Psathyrella asperospora, Russula clelandii, Tricholoma sp. AU2 and Xerula mundroola.  相似文献   

11.
Abstract  Pachydellus hades (Halliday) (Acari: Pachylaelapidae) was described from Jenolan Caves, NSW, Australia, and was thought to be an Australian endemic species. It is now known that this species is abundant in Slovakia and other parts of Europe, but its presence there was not recognised because it had been misidentified as other species. It appears likely that this species was introduced from Europe into Australia through human activities. The Australian type locality of this species gives a misleading impression of its native range.  相似文献   

12.
Book Reviews     
Book reviewed in this article:
NIELSEN, E. S.; EDWARDS, D. S.; RANGSI, T. V. (eds): Checklist of the Lepidoptera of Australia. Monographs on Australian Lepidoptera,
CALDER A A.: Click-beetles: genera of Australian Elateridae (Coleoptera). Monographs on invertebrate taxonomy
HARTL, B.; MARKOWSKI, (eds): Ecological genetics in mammals 11. Acta Theriologica
BAUER, K.; SCHREIBER, A.: Primate phylogeny from a human perspective.  相似文献   

13.
Extinction and artificial reduction in the size of geographical ranges of many species have occurred extensively across the globe because of human activities. In particular, Australian mammals have suffered heavily in the last two hundred years, with the highest number of reported cases of mammal extinctions anywhere. In the present study, we investigated the extent to which human impact has affected contemporary macroecological patterns in Australian terrestrial mammals. After examining patterns relating to body size and range size among the contemporary mammal fauna, we removed the effects of the last two hundred years of human impact by exploring patterns in the pre‐European assemblage. This permitted us to determine whether contemporary macroecological patterns are distortions of pre‐European patterns. In contrast to the expected pattern of a significant positive relationship between body size and range size, our results showed no significant association for the complete fauna in both cross‐species and phylogenetic analyses, even when data were corrected for species extinctions and range reductions. Analyses within families and among species with the same dietary strategy revealed three significant positive relationships (Macropodidae, Peramelidae, and herbivores) and one significant negative relationship (insectivores) within the contemporary assemblage that disappeared when the pre‐European assemblage was analysed. A positive relationship also emerged in the pre‐European assemblage for the Vombatidae that was not apparent in the contemporary fauna. Thus, correcting for human impact revealed important distortions among contemporary macroecological relationships that have been brought about by human‐induced range reduction and extinction. These findings not only provide further evidence that the Australian continent presents a unique and valuable opportunity with which to test the generality of macroecological patterns, but they also have important ramifications for the analysis and interpretation of contemporary macroecological datasets.  相似文献   

14.
The deserts of the Australian outback are ideal territories for dromedary camels, Camelus dromedarius. Dromedaries' flexible adaptations allow them to eat 80% of Australian plant species and they obtain much of their water through ingesting vegetation; they thrive where other species perish. In many ways, the dromedary could be said to “belong” in this harsh environment. Yet for numerous Australians, particularly ranchers, conservation managers, and increasingly local and national governments, camels are perceived as pests and unwelcome invaders. Anthropologists studying human classifications of non-human animals have suggested that those species or populations that fail to fit neatly into existing classification systems come to be considered “out of place,” particularly when they enter human domains or disturb existing perceptual boundaries of environmental order. Through exploring and analyzing academic, government, and media publications, this review proposes that today's Australian dromedaries exemplify “animals out of place” and discusses how and why they have developed this status. It is further suggested that in addition to being classified as “out of place” in Australia, the dromedary has also become “out of time,” as its classification has transformed with temporal shifts in human circumstances, cultural values, and worldviews.  相似文献   

15.
Despite the increasing popularity of seafood in Australia and various reports of infection with transmissible parasites in Australian edible aquatic animals such as fish, the number of reported cases of human infections in the country is low. This raised the question that Australian medical doctors may not be fully aware of the presence of these parasites in Australia, which in turn can lead to misdiagnosis of infections. This also may lead to an underestimation of the risk seafood-borne parasites may pose to public health. This preliminary study was conducted to determine the awareness and level of knowledge among Australian medical practitioners in New South Wales, the most populated and multicultural state in Australia, about seafood-borne parasitic diseases. Medical doctors, both general practitioners and gastroenterologists, were surveyed through an anonymous questionnaire (n = 376). Although the response rate was low at 11%, participants represented a diverse group in terms of gender, age, nationality and expertise. Despite several publications on occurrence of zoonotic parasites in Australian fish and other edible aquatic animals, and also in humans in the country, all respondents said no seafood-borne parasite had been reported as being seen within Australian or overseas practice. Although, due to low response rate, we are unable to confidently comment on the level of awareness, the findings of this study clearly suggest that further research is needed to investigate the extent of unawareness among Australian medical doctors about these highly important parasites and understanding the underlying issues in medical education that lead to the unawareness.  相似文献   

16.
Since their introduction to the toad‐free Australian continent cane toads (Bufo marinus) have caused a dramatic increase in naïve varanid mortality when these large lizards attempt to feed on this toxic amphibian. In contrast Asian–African varanids, which have coevolved with toads, are resistant to toad toxin. Toad toxins, such as Bufalin target the H1‐H2 domain of the α1 subunit of the sodium‐potassium‐ATPase enzyme. Sequencing of this domain revealed identical nucleotide sequences in four Asian as well as in three African varanids, and identical sequences in all 11 Australian varanids. However, compared to the Asian–African varanids, the Australian varanids showed four‐base‐pair substitutions, resulting in the alteration in three of the 12 amino acids representing the H1‐H2 domain. The phenotypic effect of the substitutions was investigated in human embryonic kidney (HEK) 293 cells stably transfected with the Australian and the Asian–African H1‐H2 domains. The transfections resulted in an approximate 3000‐fold reduction in resistance to Bufalin in the Australian HEK293 cells compared to the Asian–African HEK293 cells, demonstrating the critical role of this minor mutation in providing Bufalin resistance. Our study hence presents a clear link between genotype and phenotype, a critical step in understanding the evolution of phenotypic diversity.  相似文献   

17.
Primary cell lines were established from cultures of tail and toe clips of five species of Australian dragon lizards: Tympanocryptis pinguicolla, Tympanocryptis sp., Ctenophorus fordi, Amphibolurus norrisi and Pogona vitticeps. The start of exponential cell growth ranged from 1 to 5 weeks. Cultures from all specimens had fibroblastic morphology. Cell lines were propagated continuously up to ten passages, cryopreserved and recovered successfully. We found no reduction in cell viability after short term (<6 months) storage at −80 °C. Mitotic metaphase chromosomes were harvested from these cell lines and used in differential staining, banding and fluorescent in situ hybridisation. Cell lines maintained normal diploidy in all species. This study reports a simple non-invasive method for establishing primary cell lines from Australian dragon lizards without sacrifice. The method is likely to be applicable to a range of species. Such cell lines provide a virtually unlimited source of material for cytogenetic, evolutionary and genomic studies.  相似文献   

18.
While the microbiota resident in the human gut is now known to provide a range of functions relevant to host health, many of the microbial members of the community have not yet been cultured or are represented by a limited number of isolates. We describe here the draft genome sequence of Turicibacter sanguinis PC909, isolated from a pooled healthy human fecal sample as part of the Australian Human Gut Microbiome Project.  相似文献   

19.
Australian funnel-web spiders are generally considered the most dangerous spiders in the world, with envenomations from the Sydney funnel-web spider Atrax robustus resulting in at least 14 human fatalities prior to the introduction of an effective anti-venom in 1980. The clinical envenomation syndrome resulting from bites by Australian funnel-web spiders is due to a single 42-residue peptide known as δ-hexatoxin. This peptide delays the inactivation of voltage-gated sodium channels, which results in spontaneous repetitive firing and prolongation of action potentials, thereby causing massive neurotransmitter release from both somatic and autonomic nerve endings. Here we show that δ-hexatoxin from the Australian funnel-web spider Hadronyche versuta is produced from an intronless gene that encodes a prepropeptide that is post-translationally processed to yield the mature toxin. A limited sampling of genes encoding unrelated venom peptides from this spider indicated that they are all intronless. Thus, in distinct contrast to cone snails and scorpions, whose toxin genes contain introns, spiders may have developed a quite different genetic strategy for evolving their venom peptidome.  相似文献   

20.
Most genetic data suggest that Australian aborigines and Southeast Asians associate, but their relative evolutionary relationship has remained obscure. Historically, the study of tooth crown variables has been important in establishing phylogenetic relationships. Through the quantification of whole tooth structure (GDP), including root, pulp, and enamel, a likely Eurasian phylogeny emerged from a canonical discriminant analysis of the microevolution among the populations. The analysis suggested that in modern human evolutionary history, Australian aborigines are the best representative extant population (first branch) from an unknown antecedent Eurasian founder population. The next branch from the Asian-based antecedent population was Caucasoids. Within the resident antecedent East Asian population, Southeast Asians then evolved, followed by a branch that lead to antecedent east Central Asians. Mongolians and all Native Americans independently evolved from this antecedent east Central Asian population. The relatively short morphogenetic separation between two areas that have been isolated for great periods of time, i.e., Australian aborigines and Native Americans, suggests that their association is not due to gene flow.  相似文献   

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