East-West Genetic Differentiation in Musk Ducks (Biziura lobata) of Australia Suggests Late Pleistocene Divergence at the Nullarbor Plain

Musk Ducks (Biziura lobata) are endemic to Australia and occur as two geographically isolated populations separated by the Nullarbor Plain, a vast arid region in southern Australia. We studied genetic variation in Musk Duck populations at coarse (eastern versus western Australia) and fine scales (four sites within eastern Australia). We found significant genetic structure between eastern and western Australia in the mtDNA control region (UST = 0.747), one nuclear intron (UST = 0.193) and eight microsatellite loci (FST = 0.035). In contrast, there was little genetic structure between Kangaroo Island and adjacent mainland regions within eastern Australia. One small population of Musk Ducks in Victoria (Lake Wendouree) differed from both Kangaroo Island and the remainder of mainland eastern Australia, possibly due to genetic drift exacerbated by inbreeding and small population size. The observed low pairwise distance between the eastern and western mtDNA lineages (0.36%) suggests that they diverged near the end of the Pleistocene, a period characterised by frequent shifts between wet and arid conditions in central Australia. Our genetic results corroborate the display call divergence and Mathews’ (Austral Avian Record 2:83–107, 1914) subspecies classification, and confirm that eastern and western populations of Musk Duck are currently isolated from each other

Study of Transfer of Musk Compounds in Abiotic and Biotic Components of Aquatic Ecosystems

Práce byla zaměřena na stanovení musk sloučenin v různých složkách životního prostředí. Syntetické musk sloučeniny jsou organické látky běžně používané jako vonné složky detergentů, parfémů, kosmetiky a ostatních produktů osobní péče. Tyto sloučeniny kontaminují prostřednictvím komunální odpadní vody z čistíren odpadních vod vodní prostředí. Výsledkem je akumulace těchto analytů v životním prostředí a jejich výskyt v potravním řetězci. Syntetické vonné látky jsou také běžně detekovány v lidském těle; obecně patří mezi relativně nové perzistentní organické polutanty (POP) vzhledem ke své perzistenci, bioakumulaci a potenciální toxicitě. Základem této práce byla optimalizace metod pro stanovení vybraných syntetických vonných látek v odpadní vodě (komunální, průmyslové) a v rybí svalovině. Tyto analyty byly zjišťovány v odpadní vodě [čistírna odpadních vod (ČOV) Brno – Modřice; závod na výrobu kosmetiky] a v rybách Squalius cephalus, které byly odloveny z řeky Svratky. Vybrané analyty (14 látek) pocházely ze skupiny nitromusk, polycyklických musk a lineárních musk sloučenin. Pro izolaci analytů z reálných vzorků odpadní vody byla použita metoda mikroextrakce na tuhou fázi (SPME), pro izolaci analytů ze vzorků ryb byla použita metoda zrychlené extrakce rozpouštědlem (PSE). Identifikace a kvantifikace analytů byla provedena vysokorozlišovací plynovou chromatografií s hmotnostně-spektrometrickou detekcí (GC-MS). Z výsledků vyplývá, že z polycyklických musk sloučenin dosahovaly nejvyšších koncentrací na přítoku i odtoku z ČOV Brno – Modřice galaxolid (g.l-1) a tonalid (desetiny g.l-1). Nejčastěji stanovovanou nitromusk sloučeninou v odpadní vodě byl musk keton (setiny g.l-1). Lineární musk sloučeniny byly detekovány ve všech vzorcích surové odpadní vody (g.l-1). Celková účinnost odstranění syntetických musk sloučenin z odpadní vody na dané ČOV se pohybuje v těchto rozmezích: nitromusk sloučeniny 34,4 – 85,4 %, polycyklické musk sloučeniny 36,7 – 53,3 % a lineární musk sloučeniny 90,5 – 99,9 %. Na podkladě výsledků lze konstatovat, že odpadní voda (odtok z ČOV) je primárním zdrojem musk sloučenin, a to zejména polycyklických, v životním prostředí. Rovněž bylo prokázáno, že ultrafiltrace v kosmetickém závodu je vysoce účinnou technologií pro odstranění nitromusk a polycyklických musk sloučenin z průmyslové odpadní vody. Z výsledků hodnocení kontaminace ryb musk sloučeninami vyplývá, že nejvyšších koncentrací dosahoval galaxolid (desítky g.kg-1 ž.hm.). Výsledky potvrzují ubikvitární výskyt musk sloučenin v životním prostředí a omezené použití nitromusk sloučenin v důsledku jejich potenciálních toxických vlastností. Bylo prokázáno, že ČOV Brno – Modřice má významný podíl na hodnotách obsahu polycyklických musk sloučenin (tonalidu, galaxolidu) v rybách odlovených z řeky Svratky.This work was focused on the determination of musk compounds in various components of the environment. Synthetic musk compounds are organic substances commonly used as fragrant constituents of detergents, perfumes, cosmetics and other personal care products (PCPs). These compounds contaminate the aquatic environment through municipal wastewater from sewage treatment plants. The result is accumulation of these analytes in the environment and their occurrence in food chain. Synthetic fragrances are commonly detected also in human body; these substances generally belong among relatively new persistent organic pollutants (POPs) because of their persistence, bioaccumulation, and potential toxicity. The aim of this work was to optimize the methods for the determination of selected synthetic fragrances in wastewater (municipal, industrial) and in fish muscle. These analytes were determined in wastewater [the wastewater treatment plant (WWTP) Brno – Modřice, cosmetic manufacturing plant] and in fish Squalius cephalus that had been caught in the river Svratka. The selected analytes (14 substances) originate from the group of nitromusk, polycyclic musk and linear musk compounds. Solid phase microextraction (SPME) [for wastewater samples] and pressurized solvent extraction (PSE) [for fish samples] were used for isolation of analytes from real samples. The identification and quantification of analytes were carried out by high resolution gas chromatography coupled with mass spectrometry detection (GC-MS). The results show that galaxolide (g.L-1) and tonalide (tenths of g.L-1) were polycyclic musk compounds which were found at the highest concentration level in influent and also in effluent samples from the WWTP Brno – Modřice. The most extended nitromusk compound was musk ketone (hundredths of g.L-1). Linear musk compounds were detected in all influent samples (g.L-1). The overall removal efficiency of synthetic musk compounds from wastewater in the WWTP varies within the following ranges: nitromusk compounds 34.4 % – 85.4 %, polycyclic musk compounds 36.7 % – 53.3 % and linear musk compounds 90.5 % – 99.9 %. On the basis of the results it can be stated that wastewater (effluent from the WWTP) is the primary source of musk compounds, especially of the polycyclic ones in the environment. It has been also shown that ultrafiltration used in a cosmetic plant is a highly efficient technology for removing nitromusk and polycyclic musk compounds from industry wastewater. The results from evaluation of the fish contamination by musk compounds show that galaxolide was the substance which reached the highest concentration levels (tens of g.kg-1 l.w.). The results corroborate ubiquitous occurrence of musk compounds in the environment and reduction of using of nitromusk compounds due to their potential toxic properties. It has been shown that the insufficiency of the purifying procedures used in the WWTP Brno – Modřice has a significant influence on the concentration level of polycyclic musk compounds (tonalide, galaxolide) in fish caught from the river Svratka.

Myasthenia gravis patients with anti-MuSK antibodies [Miastenija gravis kod bolesnika s pozitivnim protutijelima na MuSK]

In myasthenia gravis (MG) patients without detectable anti-acetylcholine receptor (anti-AChR) antibody, referred to as seronegative myasthenia gravis patients, there is a variable proportion of patients with antibodies against the muscle specific kinase (MuSK). MuSK antibodies were found in 8 (29.6%) of our 27 patients with generalized MG without anti-AChR antibodies. All these patients were female. The age at the onset ranged from 22 to 38 years. All patients had ocular and bulbar symptoms, and two patients also had generalized limb weakness. Two patients had pure ocular symptoms for 7 or 8 years before the development of bulbar symptoms. All anti-MuSK positive patients were treated with immunosuppressive drugs, three received plasmapheresis and one patient required mechanical ventilation. Our results are consistent with other literature reports

Optimisation of Enzyme Aided Peeling of Musk Lime (Citrus Mitis B.) and Development of Its Candied Peel

Studies on the optimisation of enzyme peeling of citrus fruits were carried out on musk lime (Citrus mitis B.). The time taken to peel musk lime by enzyme (Peelzym II) was minimised with increasing enzyme concentration and application of vacuum pressure. The optimum enzyme concentration and optimum vacuum pressure for peeling musk lime peel was 1.0% (v/w) and 700 mm Hg, respectively. The effect of vacuum pressure in physico-chemical changes of peeled fruits of musk lime (Citrus mitis B.) during enzymatic peeling was studied. The pH, total soluble solids, citric acid, ascorbic acid, moisture, total pectin, tannin and sugar contents in the puree of peeled musk lime were not significantly affected by the vacuum pressure, except, total pectin content and 'b' value of puree colour at very high vacuum pressure (700 mm Hg). The naringin content has also been analysed in the puree, seeds and peel (discarded) of peeled musk lime. The lime. The naringin content in the puree and seeds of peeled musk lime were not significantly affected by the vacuum pressure, however, naringin content in the peel was significantly affected at very high vacuum pressure. The development of candied musk lime peel was carried out using Response Surface Methodology (RSM) and ECHIP® software. In this study, the RSM method was found to be effective in making a new product when the developed product (candied musk lime peel) had matched the sensory profile of a target product (commercial candied peel). This method was then confirmed by a verification process between the experimental value from the developed product (candied musk lime peel) with the target value obtained from the overlapping contour maps of ingredients in the making of optimum candied musk lime peel. Results from sensory evaluation also showed that most of the panelists liked the taste of the product compared to other sensory attributes tested. In comparison, the developed candied musk lime peel has a similar profile in terms of appearance, odour and taste of sourness and bitterness to that of commercial candied peel. Therefore, the candied musk lime peel developed in this study has the potential to be commercialised

Flow cytofluorimetric analysis of anti-LRP4 (LDL receptor-related protein 4) autoantibodies in Italian patients with Myasthenia gravis

Background: Myasthenia gravis (MG) is an autoimmune disease in which 90% of patients have autoanti-bodies against the muscle nicotinic acetylcholine receptor (AChR), while autoantibodies to muscle-specific tyrosine kinase (MuSK) have been detected in half (5%) of the remaining 10%. Recently, the low-density lipoprotein receptor-related protein 4(LRP4), identified as the agrin receptor, has been recognized as a third autoimmune target in a significant portion of the double sero-negative (dSN) myasthenic individuals, with variable frequency depending on different methods and origin countries of the tested population. There is also convincing experimental evidence that anti-LRP4 autoantibodies may cause MG. Methods: The aim of this study was to test the presence and diagnostic significance of anti-LRP4 autoantibodies in an Italian population of 101 myasthenic patients (55 dSN, 23 AChR positive and 23 MuSK positive), 45 healthy blood donors and 40 patients with other neurological diseases as controls. All sera were analyzed by a cell-based antigen assay employing LRP4-transfected HEK293T cells, along with a flow cytofluorimetric detection system. Results: We found a 14.5% (8/55) frequency of positivity in the dSN-MG group and a 13% frequency of co-occurrence (3/23) in both AChR and MuSK positive patients; moreover, we report a younger female prevalence with a mild form of disease in LRP4-positive dSN-MG individuals. Conclusion: Our data confirm LRP4 as a new autoimmune target, supporting the value of including anti-LRP4 antibodies in further studies on Myasthenia gravis

Autoantibodies to Agrin in Myasthenia Gravis Patients

To determine if patients with myasthenia gravis (MG) have antibodies to agrin, a proteoglycan released by motor neurons and is critical for neuromuscular junction (NMJ) formation, we collected serum samples from 93 patients with MG with known status of antibodies to acetylcholine receptor (AChR), muscle specific kinase (MuSK) and lipoprotein-related 4 (LRP4) and samples from control subjects (healthy individuals and individuals with other diseases). Sera were assayed for antibodies to agrin. We found antibodies to agrin in 7 serum samples of MG patients. None of the 25 healthy controls and none of the 55 control neurological patients had agrin antibodies. Two of the four triple negative MG patients (i.e., no detectable AChR, MuSK or LRP4 antibodies, AChR-/MuSK-/LRP4-) had antibodies against agrin. In addition, agrin antibodies were detected in 5 out of 83 AChR+/MuSK-/LRP4- patients but were not found in the 6 patients with MuSK antibodies (AChR-/MuSK+/LRP4-). Sera from MG patients with agrin antibodies were able to recognize recombinant agrin in conditioned media and in transfected HEK293 cells. These sera also inhibited the agrin-induced MuSK phosphorylation and AChR clustering in muscle cells. Together, these observations indicate that agrin is another autoantigen in patients with MG and agrin autoantibodies may be pathogenic through inhibition of agrin/LRP4/MuSK signaling at the NMJ

Evaluation of occurence of musk compounds in water ecosystem

V této bakalářské práci je řešena problematika výskytu syntetických musk sloučenin ve složkách životního prostředí, zejména vodního ekosystému. Práce obsahuje základní rozdělení syntetických musk sloučenin spolu s výčtem jejich nejvýznamnějších zástupců, z nichž byli vybráni zástupci, kteří budou podrobněji studováni v diplomové práci. Sledovanými zástupci jsou linalool, citronellol a isobornylacetát. Byly popsány základní fyzikálně chemické vlastnosti těchto vonných látek a jejich toxikologické a environmentální aspekty na životní prostředí. Součástí práce je podrobný popis analytického stanovení syntetických musk sloučenin.This bachelor’s thesis is concerned with synthetic musk compounds and their presence in the environment, particularly in water ecosystem. The thesis contains fundamental classification of synthetic musk compounds together with specification and detailed description of their most significant representatives. Among them are linalool, citronellol, and isobornyle acetate which will be studied further in master’s thesis. Fundamental physical-chemical properties of these odoriferous compounds and their toxicological and environmental impact are studied. Also part of this thesis is a detailed description of synthetic musk compounds’ analytical determination.

Exercise “Musk Ox”: Asserting Sovereignty “North of 60”

The Second World War was over and the Canadian armed forces were being reduced rapidly. The first chilly blasts of the Cold War had not yet penetrated to the consciousness of most Canadians. What role could the forces play in the postwar world? The most obvious answer was to revert to those interwar operations that had most directly benefited the nation—aerial surveys, northern communications, limited engineering projects. New tasks had evolved; aerial search and rescue was an example. The Canadian government was aware that it had neglected the north during the war; the American presence in the Alaska Highway, CANOL, and aerial delivery routes via the Arctic had been more prominent than that of the nominal owners of the region. This was continuing even into the postwar period; early in 1946 the USS Midway was cruising in the Labrador Sea and Davis Strait areas, experiencing Arctic flying conditions and noting the effects of sub-zero temperatures on carrier-borne aircraft. “Musk Ox,” publicly described as a test of military equipment and capabilities in the north, was a gesture to reassert Canadian sovereignty “north of 60.

The synaptic Muscle-Specific Kinase (MuSK) complex: new partners, new functions.

The muscle-specific kinase MuSK is part of an agrin receptor complex which stimulates tyrosine phosphorylation and drives clustering of acetylcholine receptors (AChRs) in the postsynaptic membrane at the vertebrate neuromuscular junction. MuSK also regulates synaptic gene transcription in subsynaptic nuclei. Over the past few years decisive progress has been made in the identification of MuSK effectors, helping at understanding its function in the formation of the NMJ. Alike AChR, MuSK and several of its partners are the target of mutations responsible for diseases of the NMJ, such as congenital myasthenic syndromes. This minireview will focus on the multiple MuSK effectors so far identified that place MuSK at the center of a multifunctional signaling complex involved in the organization of the NMJ and associated disorders