Environmental Factors Influencing Hairy-Nosed Wombat Abundance in Semi-Arid Rangelands

Understanding environmental factors influencing the abundance of species is important for developing strategies to manage wildlife effectively. Long-term studies provide the most reliable information upon which to base management decisions. This is particularly important when considering threatening processes, like drought and climate change, and a species' future security. We collected data on abundance of southern hairy-nosed wombats (Lasiorhinus latifrons) on Kooloola Station in South Australia's Murraylands during nightly spot-lighting excursions in winter and spring between 1993 and 2014. Wombat numbers declined significantly after the early-mid 1990s, and were lowest in 2002–2003 in the middle of the millennium drought (late 1996–mid-2010). Despite an observed decline in grazing competition from domestic sheep and rabbits (Oryctolagus cunniculus) after 2003 and above-average rainfall in 5 of the next 11 years, the wombat population failed to recover to early–mid-1990s levels, remaining at approximately 50% of estimated abundance pre-drought. The study provides evidence that rainfall has a significant effect on southern hairy-nosed wombat population size, most likely through improvements in the availability of palatable plant species. Historical information suggests that there was a change in the grass and herbaceous layer on Kooloola Station in the mid-1970s from a pasture dominated by summer-germinating native grass and forb species, the natural diet of the southern hairy-nosed wombat, to one dominated by winter-germinating introduced weeds. Several consecutive years of above-average rainfall are needed before effective wombat population increase occurs and the size of yearly winter and spring rainfall events is strongly linked to population trends the following year. Historical information and first-hand observations suggest that dietary components (either native grasses or introduced weed species) and level of grazing competition may also interact to affect wombat survival and population recovery from drought, although this requires further testing. Together with rainfall, these factors have important implications to develop appropriate conservation and management strategies for this species in a changing climate likely to be dominated by increased drought frequency and duration. © 2020 The Wildlife Society.     

Myotone Dystrophien – und ihre Differenzialdiagnosen

The classic myotonic dystrophy, Steinert’s disease (DM1) was first described in 1909, and the second type, Ricker’s disease (DM2), in 1994. In 1992 the disease-causing mutation in DM1 was identified as a CTG repeat in the DMPK gene on chromosome 19q, and in 2001 the DM2 mutation was identified as a CCTG repeat expansion in the ZNF9 gene on chromosome 3q. Multisystemic symptoms of the diseases affect skeletal muscle, brain, eye, heart, and the endocrine system. The pathogenesis of both forms seems to be based on a gain-of-function RNA mechanism and on alterations in RNA metabolism and spliceopathy. Our review focuses on clinical features, diagnostic techniques, and new aspects of molecular pathogenesis and therapy.     

Genetik der monogenen isolierten Alopezien

The monogenic inherited isolated alopecias comprise a group of clinically and genetically heterogeneous forms of hairlessness or hair loss. Clinical classification of the isolated alopecias is based on the onset of the disorder, the regions affected, and the structure of the hair shaft. Men and women are equally affected, and the mode of inheritance is autosomal dominant or autosomal recessive. Since the identification of the keratin gene KRT86 as a cause of the so-called monilethrix in 1997, mutations in nine other genes have been identified for various isolated alopecias. These include other keratin genes for monilethrix (KRT81 and KRT83), the hairless gene for atrichia congenita/papular atrichia, the corneodesmosin gene for the autosomal dominant form of hypotrichosis simplex, and the genes desmoglein 4, lipase H, and the G-protein-coupled receptor P2RY5 (LPAR6) for the autosomal recessive forms of hypotrichosis. Molecular genetic and pathophysiological studies of these rare disorders of hair development have contributed significantly to our understanding of the basic mechanisms of hair loss as well as the physiological mechanisms of hair growth.     

CD14 C-159T and early infection with Pseudomonas aeruginosa in children with cystic fibrosis

Early acquisition of Pseudomonas aeruginosa is associated with a poorer prognosis in patients with cystic fibrosis. We investigated whether polymorphisms in CD14, the lipopolysaccharide receptor, increase the risk of early infection. Forty-five children with cystic fibrosis were investigated with annual bronchoalveolar lavage (BAL) and plasma sCD14 levels. Plasma sCD14 levels were significantly lower in children from whom P.aeruginosa was subsequently isolated (492.75 μg/ml vs. 1339.43 μg/ml, p = 0.018). Those with the CD14 -159CC genotype had a significantly increased risk of early infection with P.aeruginosa suggesting that CD14 C-159T plays a role in determining the risk of early infection with P.aeruginosa.     

Entwicklung der Zähne

Dental development takes place in stages over a long period of time. From the 6ths embryonal week, when the dental lamina develops, tooth number and shape are formed, followed by the production of dental hard tissues. Genetic dental developmental defects are not rare. Mostly these defects affect the tooth number, predominantly resulting in a decrease tooth number (hypodontia) which can occur isolated or as a finding in genetic syndromes such as Rieger syndrome, Witkop syndrome or several ectodermal dysplasias. Genetic defects of dental hard tissues are less frequent, different types of isolated enamel defects (amelogenesis imperfecta) are known. Dentinogenesis imperfecta or other dentinal defects are either caused by different mutations of the DSPP gene or a part of osteogenesis imperfecta.     

Sperm transport and storage in the agile antechinus (Antechinus agilis).

This study was an examination of the timing of ejaculation and the dynamics of sperm transport in the female reproductive tract of the agile Antechinus (Antechinus agilis) and the relationship of these parameters to single and multiple matings. Mating in this species is characteristically long compared with that of other mammals, lasting for up to 8-12 h during which time the pair remain locked together. After the first hour of mating, only approximately 40% of males had ejaculated, but by the third hour all males had ejaculated. The total number of spermatozoa extracted from the female tract remained at approximately 30 x 10(3) spermatozoa per side over the next 9 h of copulation. After completion of male/female access (12 h), approximately 56% of spermatozoa extracted were located in the lower isthmic region of the oviduct where specialized sperm storage crypts are located. The number of spermatozoa extracted from the female reproductive tract did not decline over the next 3 days, but there was a change in the distribution of spermatozoa with an increase in the proportion of extracted spermatozoa stored in the lower isthmus (approximately 76%). However, 7 to 14 days after mating, only approximately 30% of the stored spermatozoa ( approximately 9.4 x 10(3) spermatozoa per side) were still present in the isthmus. When females were mated with a second male on a consecutive day, the sperm numbers extracted from the tract were about twice that deposited during single mating, with sperm transport to the lower isthmus occurring over a similar time frame. Although the occurrence of extended copulations in the wild has not yet been confirmed, these laboratory results suggest that similar periods of copulation are likely, since completion of the ejaculation process requires at least 3 h. The extended copulation in A. agilis reduces the possibility of an early second mating, which might interfere with the normal transport and crypt colonization of spermatozoa through competition.     

Das Marfan-Syndrom und verwandte monogene Krankheiten der Aorta

Marfan syndrome (MFS) is an autosomal dominant, pleiotropic disease of the connective tissue with a prevalence of about 1 in 5000 persons. MFS is characterized by manifestations in the cardiovascular system, eye, skeleton, lung, skin, and dura mater that show a high degree of intra- and interfamilial variability. Many manifestations develop during or shortly before puberty; severe complications rarely occur before adulthood. Many patients with MFS display a so-called marfanoid habitus with tall stature, dolichostenomelia (long, narrow extremities), dolichocephaly (disproportionately long and narrow head), as well as other skeletal abnormalities such as scoliosis and pes planus. Scoliosis occurs in approximately 60% of those affected, pectus deformities in up to two thirds. Ectopia lentis is seen in many patients with MFS and is almost always bilateral. MFS is characterized by a high risk for complications such as severe scoliosis or pectus deformities, spontaneous pneumothorax, retinal detachment, or glaucoma secondary to lens luxation. The most severe complications occur in the cardiovascular system, including in particular acute dissection of the ascending aorta, which generally follows a long period of progressive aortic dilatation. Before the introduction of modern treatment modalities, the average life expectancy of persons with MFS was estimated to be 32 years. Today, with medical care in multidisciplinary centers, an average life expectancy of over 60 years can be achieved. This article offers a review of established and novel concepts for the diagnosis and treatment of MFS and other hereditary diseases of the aorta.     

Klinik und Genetik des familiären Darmkrebses

Familial clustering of colorectal cancer (CRC) and early disease onset are indicators of an inherited tumour syndrome. Monogenic dispositions account for 3–5% of all CRC cases and are subdivided into hereditary non-polyposis colorectal cancer (HNPCC/Lynch syndrome) and various gastrointestinal polyposis syndromes. Many of these syndromes are characterised by a broad spectrum of extracolonic tumours. Early detection and accurate classification are essential in providing effective surveillance and treatment. Initial diagnosis is based on endoscopic and histological findings as well as on the presence of extracolonic manifestations and family history. Molecular genetic examination is important for the differential diagnosis, evaluation of recurrence risk, and predictive testing of asymptomatic at risk individuals; it is performed according to largely standardised algorithms. Diagnostic difficulties are common among the hamartomatous polyposes due to their broad phenotypic overlap and frequent uncertainties in histological evaluation, as well as among patients with few adenomas. Risk-adapted surveillance guidelines have been established for HNPCC and for the more frequently observed polyposis syndromes. Beyond established tumour syndromes, familial clustering of CRC (which is often of late onset) or the occurrence of few adenomas is likely to be based upon a multifactorial (complex) etiology. Although identification of the underlying genetic risk factors and biological pathways is still in the early stages, rapid progress is being made due to methodical developments such as genome-wide association studies and CNV analysis.