Disseminated Pelvic Actinomycosis Caused by Actinomyces Naeslundii.

Actinomycosis is a chronic bacterial infection characterized by continuous local spread, irrespective of anatomical barriers, and granulomatous suppurative inflammation. Due to its expansive local growth, it can simulate a malignant tumour. Subsequent hematogenous dissemination to distant organs can mimic metastases and further increase suspicion for malignancy. A case of severe disseminated pelvic actinomycosis associated with intrauterine device is described here. The patient presented with a pelvic mass mimicking a tumour, bilateral ureteral obstruction, ascites, multinodular involvement of the liver, lungs and spleen, inferior vena cava thrombosis and extreme cachexia. Actinomycosis was diagnosed by liver biopsy and confirmed by culture of Actinomyces naeslundii from extracted intrauterine contraceptive device (IUD). Prolonged treatment with aminopenicillin and surgery resulted in recovery with moderate sequelae.

Extensive Cryptic Diversity in the Terrestrial Diatom Pinnularia borealis (Bacillariophyceae).

With the increasing application of molecular techniques for diatom species discovery and identification, it is important both from a taxonomic as well as an ecological and applied perspective, to understand in which groups morphological species delimitation is congruent with molecular approaches, or needs reconsideration. Moreover, such studies can improve our understanding of morphological trait evolution in this important group of microalgae. In this study, we used morphometric analysis on light microscopy (LM) micrographs in SHERPA, detailed scanning electron microscopy (SEM), and cytological observations in LM to examine 70 clones belonging to eight distinct molecular lineages of the cosmopolitan terrestrial diatom Pinnularia borealis. Due to high within-lineage variation, no conclusive morphological separation in LM nor SEM could be detected. Morphological stasis due to the "low-morphology" problem or stabilizing selection, as well as parallel/convergent evolution, phenotypic plasticity and structural inheritance are discussed as potential drivers for the observations. Altogether, P. borealis is truly cryptic, in contrast to the majority of other diatom species complexes which turned out to be pseudo-cryptic following detailed morphological analysis.

Molecular and morphological diversity of Zygnema and Zygnemopsis (Zygnematophyceae, Streptophyta) from Svalbard (High Arctic).

Filamentous conjugating green microalgae (Zygnematophyceae, Streptophyta) belong to the most common primary producers in polar hydro-terrestrial environments such as meltwater streamlets and shallow pools. The mats formed by these organisms are mostly composed of sterile filaments with Zygnema morphology, but the extent of their diversity remains unknown. Traditional taxonomy of this group is based on reproductive morphology, but sexual reproduction (conjugation and formation of resistant zygospores) is very rare in extreme conditions. In the present study we gave the first record of zygospore formation in Svalbard field samples, and identified conjugating filaments as Zygnemopsis lamellata and Zygnema cf. calosporum. We applied molecular phylogeny to study genetic diversity of sterile Zygnema filaments from Svalbard in the High Arctic. Based on analysis of 143 rbcL sequences, we revealed a surprisingly high molecular diversity: 12 Arctic Zygnema genotypes and one Zygnemopsis genotype were found. In addition, we characterized individual Arctic genotypes based on cell width and chloroplast morphology using light and confocal laser scanning microscopy. Our findings highlight the importance of a molecular approach when working with sterile filamentous Zygnematophyceae, as hidden diversity might be very beneficial for adaptation to harsh environmental conditions, and experimental results could be misinterpreted when hidden diversity is neglected.

[Diagnosis, treatment and prophylaxis of malaria in the Czech Republic].

Malaria represents the most important parasitic infection imported from the tropics causing death in 1-2 % of travelers with this diagnosis. Around 30 cases of malaria are diagnosed in the Czech Republic every year. Fever is the most common clinical presentation. The most severe forms of malaria are caused by Plasmodium falciparum. The diagnosis of malaria is based on examination of stained thick and thin blood smears. This method enables determination of Plasmodium species and parasite count. The treatment of ma-laria has to be initiated immediately after the laboratory confirmation. In the Czech Republic, uncomplicated falciparum malaria is treated by oral administration of artemether/lumefantrine or atovaquone/proguanil. Complicated falciparum malaria is treated by parenteral administration of quinine in combination with clindamycin. For the chemoprophylaxis of malaria in travelers to the highly endemic regions, atovaquone/proguanil, doxycycline or mefloquine are recommended.

[Lactic acidosis due to metformin accumulation complicating acute gastroenteritis].

Lactic acidosis is the most severe adverse effect associated with metformin therapy of type 2 diabetes mellitus. The risk increases in patients with impaired renal function, most commonly due to diabetic nephropathy, and may be augmented when concurrent medication with a negative impact on renal function is used. The authors present a series of three patients who were admitted to a department of infectious diseases for acute gastroenteritis and within a few hours developed shock syndrome caused by severe lactic acidosis due to accumulation of metformin.

Nitrogen limitation and slow drying induce desiccation tolerance in conjugating green algae (Zygnematophyceae, Streptophyta) from polar habitats.

BACKGROUND: Filamentous Zygnematophyceae are typical components of algal mats in the polar hydro-terrestrial environment. Under field conditions, they form senescent vegetative cells, designated as pre-akinetes, which are tolerant to desiccation and osmotic stress. KEY FINDINGS: Pre-akinete formation and desiccation tolerance was investigated experimentally under monitored laboratory conditions in four strains of Arctic and Antarctic isolates with vegetative Zygnema sp. morphology. Phylogenetic analyses of rbcL sequences revealed one Arctic strain as genus Zygnemopsis, phylogenetically distant from the closely related Zygnema strains. Algae were cultivated in liquid or on solidified medium (9 weeks), supplemented with or lacking nitrogen. Nitrogen-free cultures (liquid as well as solidified) consisted of well-developed pre-akinetes after this period. Desiccation experiments were performed at three different drying rates (rapid: 10% relative humidity, slow: 86% rh and very slow); viability, effective quantum yield of PS II, visual and ultrastructural changes were monitored. Recovery and viability of pre-akinetes were clearly dependent on the drying rate: slower desiccation led to higher levels of survival. Pre-akinetes survived rapid drying after acclimation by very slow desiccation. CONCLUSIONS: The formation of pre-akinetes in polar Zygnema spp. and Zygnemopsis sp. is induced by nitrogen limitation. Pre-akinetes, modified vegetative cells, rather than specialized stages of the life cycle, can be hardened by mild desiccation stress to survive rapid drying. Naturally hardened pre-akinetes play a key role in stress tolerance and dispersal under the extreme conditions of polar regions, where sexual reproduction and production of dormant stages is largely suppressed.

Exploration of nuclear DNA markers for population structure assessment in the desmid Micrasterias rotata (Zygnematophyceae, Streptophyta).

Freshwater green microalgae are diverse and widely distributed across the globe, yet the population structuring of these organisms is poorly understood. We assessed the degree of genetic diversity and differentiation of the desmid species, Micrasterias rotata. First, we compared the sequences of four nuclear regions (actin, gapC1, gapC2, and oee1) in 25 strains and selected the gapC1 and actin regions as the most appropriate markers for population structure assessment in this species. Population genetic structure was subsequently analyzed, based on seven populations from the Czech Republic and Ireland. Hudson's Snn statistics indicated that nearest-neighbor sequences occurred significantly more frequently within geographical populations than within the wider panmictic population. Moreover, Irish populations consistently showed higher genetic diversity than the Czech samples. These results are in accordance with the unbalanced distribution of alleles in many land plant species; however, the large genetic diversity in M. rotata differs from levels of genetic diversity found in most land plants.