Hybridization between Anguillicola crassus and A. novaezelandiae, and viability of the F1 generation.

For decades, it has remained unclear how the Asian swim bladder nematode Anguillicola crassus was able to supplant the previously stable population of its relative from New Zealand Anguillicola novaezelandiae in the Lake Bracciano, Italy. Previously, researchers have hypothesized that A. crassus possesses an ecological advantage due to a more efficient life cycle in combination with a pattern of unidirectional hybridization between A. novaezelandiae females and A. crassus males. The present study focuses on the viability of hybrid offspring and their allelic pattern, particularly in developed adult stages of the hybrid F1 generation. While the percentages of hybrid individuals from A. novaezelandiae mothers and A. crassus fathers increased from egg to adult stages, it was more distinct in egg stages of A. crassus females and A. novaezelandiae males, but did not occur in adult F1 individuals at all. Therefore, we corroborate the hypothesis of unidirectional hybridization by differentiating between egg and adult stages, and suggest this as another explanatory factor for the extinction of A. novaezelandiae in Lake Bracciano in Italy and the predominance of A. crassus.

A survey on current knowledge, practice and beliefs related to preoperative antimicrobial decolonization regimens for prevention of surgical site infections among Austrian surgeons.

BACKGROUND: Various measures are considered to reduce the risk of surgical site infection (SSI), including preoperative decolonization. Details of preoperative decolonization practices in surgical departments have not been investigated in Austria. AIM: To analyse the current situation of pre-surgical patient decolonization in national hospitals and to assess the current knowledge on this procedure among surgeons of different surgical disciplines. METHODS: A 12-point structured questionnaire was distributed to all Austrian hospitals with at least one surgical department. FINDINGS: Two-thirds (103/158; 65%) of responding surgeons stated that any type of preoperative decolonization is implemented in their surgical department. There was heterogeneity of different protocols, ranging from decolonization of only known S. aureus carriers, of a subgroup of patients, or universal decolonization of all patients before elective surgery. Octenidine was the most frequently used antimicrobial compound (60.2%), followed by mupirocin (38.8%), triclosan (14.6%), polyhexanide (12.6%), chlorhexidine (11.7%), and didecyldimonium chloride (7.8%). CONCLUSION: Preoperative decolonization seems to be performed in Austrian hospitals on a routine basis. However, this measure is implemented using a variety of modalities, antimicrobial compounds, and staff. Since our survey also demonstrated that those who are better informed about preoperative decolonization are also those who are more convinced of the usefulness of the preventive measure, future activities should not only focus on generating more comparable studies in this field, but should also include targeted education.

Parasites as drivers of key processes in aquatic ecosystems: Facts and future directions.

Despite the advances in our understanding of the ecological importance of parasites that we have made in recent years, we are still far away from having a complete picture of the ecological implications connected to parasitism. In the present paper we highlight key issues that illustrate (1) important contributions of parasites to biodiversity, (2) their integral role in ecosystems, (3) as well as their ecological effects as keystone species (4) and in biological invasion processes. By using selected examples from aquatic ecosystems we want to provide an insight and generate interest into the topic, and want to show directions for future research in the field of ecological parasitology. This may help to convince more parasitologists and ecologists contributing and advancing our understanding of the complex and fascinating interplay of parasites, hosts and ecosystems.

Competing invaders: Performance of two Anguillicola species in Lake Bracciano.

Anguillicola crassus is one of the most successful parasitic invasive species as it has spread from its original habitat in East Asia throughout the world and has acquired five new eel host species in the course of its invasion within the last three decades. Records from an Italian lake indicate that this species has even displaced an established population of its close relative A. novaezelandiae originating from New Zealand. In order to analyze the reasons for its high invasive potential, this review highlights recent studies, which substantiate the selective advantages of A. crassus over A. novaezelandiae. Laboratory infection experiments revealed that A. crassus features a less synchronized development compared to A. novaezelandiae in the European eel, which enables this species to emit eggs over a longer period of time. Differences in the time period required for first egg output and in the maturation process of second stage larvae in intermediate hosts could also be detected, which may lead to differences in infection potential. Finally, microsatellite analyses have shown that hybridization processes are possible, but might only occur between A. crassus males and A. novaezelandiae females. Taken as a whole, the sum of minor selective advantages and differences in life cycle traits could have considerably contributed to a replacement of one species by the other.

Hydrogels from phospholipid vesicles.

It is shown that phospholipid dispersions with a few percent of diacylphosphocholine PC in water can be swollen to single-phase lyotropic liquid crystalline Lα-phases by the addition of co-solvents like glycerol, 1,3-butyleneglycol BG or 1,2-propyleneglycol PG. The birefringent Lα-phases contain small unilamellar and multilamellar vesicles if the temperature of the samples is above the Krafft-Temperature Tm of the phospholipid. When such transparent birefringent viscous samples are cooled down below Tm the samples are transformed into birefringent gels. Cryo-TEM and FF-TEM measurements show that the bilayers of the vesicles are transformed from the liquid to the crystalline state during the transformation while the vesicle structure remains. The bilayers of the crystalline vesicles form adhesive contacts in the gel. Pulsed-field gradient NMR measurements show that two different kinds of water or co-solvent can be distinguished in the gels. One type of solvent molecules can diffuse like normal solvent in a continuous bulk phase. A second type of water diffuses much more slowly. This type of solvent is obviously trapped in the vesicles. The permeability of the crystalline vesicles for water and solvent molecules is much lower in the crystalline state than in the fluid state. Maximum swelling of the diacylphosphocholin dispersions occurs when the refractive index of the solvent is matched to the refractive index of the bilayers. The attraction between the bilayers is at a minimum in this state and the liquid crystalline Lα-phase's undulation forces between the bilayers push the bilayers apart. On transformation to the gel state the crystalline bilayers assume a high elastic bending rigidity. Undulations of the bilayers are now suppressed, and the bilayers can form adhesive contacts. Oscillating rheological measurements show that the gels with only 1% of phospholipids can have a storage modulus of 1000Pa. The gels are very brittle. They break when they are deformed by a few percent.

Cardicola opisthorchis n. sp. (Trematoda: Aporocotylidae) from the Pacific bluefin tuna, Thunnus orientalis (Temminck & Schlegel, 1844), cultured in Japan.

A new aporocotylid blood fluke is described, based on specimens from the ventricle of the Pacific bluefin tuna, Thunnus orientalis (Temminck et Schlegel), cultured in Wakayama and Nagasaki Prefectures, Japan. The new species is morphologically similar to the members of the genus Cardicola Short, 1953, but shows distinct differences in the body form, location of the testis and the orientation of the ootype. The body of the new species is long and slender, whereas other Cardicola species are small and generally lanceolate. The testis is mostly located posterior to the caeca and anterior to the ovary, occupying 31-45% of body length, in contrast to the known Cardicola species, whose testis is typically intercaecal. The ootype is oriented anteriorly, while in most congeners, it is directed posteriorly or horizontally. Phylogenetic analyses of this aporocotylid, together with Cardicola orientalis Ogawa, Tanaka, Sugihara et Takami, 2010 from the same host, were conducted based on DNA sequences of the ITS2 rDNA and the 28S region of ribosomal RNA. The analyses revealed that the new blood fluke belongs to the genus Cardicola despite the marked morphological differences. Thus, this aporocotylid is named Cardicola opisthorchis n. sp. and the generic diagnosis is emended in this paper. In addition, 100% identity among the ITS2 sequences from the present species, Cardicola sp. from T. orientalis in Mexico and Cardicola sp. from the northern bluefin tuna, Thunnus thynnus (Linnaeus) in Spain suggests that C. opisthorchis n. sp. has a broad geographical distribution and that it infects both the Pacific and northern bluefin tuna.

Kudoa prunusi n. sp. (Myxozoa: Multivalvulida) from the brain of Pacific bluefin tuna Thunnus orientalis (Temminck & Schlegel, 1844) cultured in Japan.

Kudoa prunusi n. sp. (Myxozoa; Multivalvulida) is described from the brain of Pacific bluefin tuna Thunnus orientalis cultured in Japan. Numerous white cysts, up to 0.5mm in size, were found on and in the brain. Spores having typically five spore valves and five polar capsules resembled a five-petal cherry blossom in apical view and were conical shape with a round bottom in side view. Average spore size was 9.63 (8.5-10.3) µm in width and 7.50 (6.7-8.6) µm in length. The spore dimensions of K. prunusi overlapped with those of Kudoa yasunagai ex Sillago ciliata having five to six spore valves, but they were clearly distinct in spore shape, 18S rDNA and 28S rDNA sequences (0.3% and 1.7% differences, respectively). Phylogenetic analysis of 18S rDNA revealed that K. prunusi grouped with the brain-infecting multivalvulid species, K. yasunagai, K. chaetodoni, K. lethrini and K. neurophila, rather than five-valved Kudoa spp. Combined with morphological, molecular and biological differences, K. prunusi was proven to be a new species.

Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea) portal of entry into the fish host.

The portal of entry and the penetration process of the myxozoan parasite Tetracapsuloides bryosalmonae are still poorly understood. In the present study, spores of T. bryosalmonae derived from the bryozoan host (malacospores) were activated chemically and mechanically to investigate their reaction after attachment to the fish host in vitro. Amoeboid movement of both sporoplasms was shown for the first time. The morphology of malacospores was assessed using scanning electron microscopy (SEM). Openings of the polar capsules and released polar filaments were visible. One sporoplasm was observed leaving the spore shell. Laboratory exposure experiments of juvenile rainbow trout Oncorhynchus mykiss to spores of T. bryosalmonae were also conducted. Single fish were incubated with 1000 to 2000 spores in 100 ml of water for 5 to 60 min. Immunohistochemically stained sections of skin and gills were examined using light microscopy, as well as ultra thin sections using transmission electron microscopy (TEM), to investigate attachment and early penetration. Whole fish and excised gills of fish exposed to a spore suspension were fixed and prepared for scanning electron microscopy. Attached and penetrating stages were found only on or in the gills, and not in the skin. Due to the low overall number of spores, only a few spores were found adjacent to the gill epithelium in TEM. No parasite stages were found on the samples used for SEM. These results indicate that the gills are the preferred entry loci for the amoeboid sporoplasms of T. bryosalmonae into the fish host.

The solubilisation of a water insoluble functionalized silicone oil in an aqueous surfactant solution: a novel mechanism for the solubilisation process.

The solubilisation of the functionalized silicone oil aminoethyl aminopropyl methylpolysiloxane WR 1300 has been investigated in aqueous solutions of the surfactant pentaethoxy-iso-tridecanol (iC(13)E(5)). The silicone oil consists of a linear backbone with an average of 200 dimethylsiloxane units and 2-3 functionalized side groups. In various applications the compound is considered a silicone oil. The surfactant iC(13)E(5) forms a L(alpha)-phase in water, and with decane a microemulsion can be obtained. The solubilisation experiments started with lamellar iC(13)E(5) phases. With proper amounts of WR 1300 transparent, optically isotropic but highly viscous single phases are formed. These phases cannot be considered true microemulsions with an oil core and a surrounding surfactant layer. Cryo-TEM micrographs show micelles with irregular shapes and about 25 nm diameter. Their size is independent of the oil/surfactant ratio. It can be explained on the basis of a model where the amino groups of the oil are all found at the surface of the micelles, limiting the radius of the aggregates to the largest length of the polydimethylsiloxane backbone between two such groups or between one end of the oil and one functionalized group. The micellar structures contain only a few siloxane molecules exposing their hydrophilic groups to the water. The functionalized silicone oil molecules can thus be considered as surfactant molecules with a few polar groups and a large hydrophobic chain from dimethyl siloxane.

Experimental transmission of malacosporean parasites from bryozoans to common carp ( Cyprinus carpio) and minnow ( Phoxinus phoxinus).

To address whether a fish host is involved in the life cycles of malacosporeans of the genus Buddenbrockia, cohabitation experiments with different bryozoan and fish species were conducted. Samples were analysed by malacosporean-specific PCR, partial sequencing of the 18S rDNA, and light and electron microscopy. Co-habitation challenges with bryozoans resulted in malacosporean infections detected mainly in the kidney of common carp (Cyprinus carpio) and minnow (Phoxinus phoxinus). Sequences of the minnow parasite and of worm-like Buddenbrockia stages in Plumatella repens were identical and showed 99.5% similarity to Buddenbrockia plumatellae and 96.3% similarity to the sequence obtained from carp. One sample, comprising 4-5 zooids of statoblast-raised bryozoans cohabitated with infected carp was PCR-positive, but no overt infection could be observed in the remaining colony. Light and electron-microscopy of kidney samples of infected minnows revealed single cells within kidney tubules, whereas in carp, sporogonic stages were found in kidney tubules. Phylogenetic analysis of the Buddenbrockia spp. known to date placed the carp-infecting species at the base of the B. plumatellae clade, but low posterior probability makes this node questionable. The present study showed that Buddenbrockia spp. were able to infect cyprinid fish, showing stages in kidney-tubules strikingly similar to those of T. bryosalmonae.

Differentially expressed parasite genes involved in host recognition and invasion of the triactinomyxon stage of Myxobolus cerebralis (Myxozoa).

The host recognition and invasion process of Myxobolus cerebralis actinospores (triactinomyxon, TAM) was studied on a genetic level. A small-scale in vitro assay was developed to activate a large number of TAMs simultaneously, and to monitor the host invasion in the absence of live fish. The transcriptomes of non-activated and in vitro-activated TAMs were compared by suppressive subtractive hybridization (SSH) to identify parasite genes involved in the host invasion process. Differential screening and a subsequent BLAST search revealed 15 of 452 SSH-library clones expressed differently in activated TAMs. None of the 15 transcripts obtained has previously been identified from M. cerebralis. Quantitative real-time PCR was used to examine the relative expression profile of 8 selected transcripts upon TAM activation and after penetration of the host. Four of these were found to be up-regulated in activated TAMs, while expression was relatively low in non-activated TAMs and in infected fish tissue, indicating that they are relevant genes during host recognition or subsequent host invasion of M. cerebralis TAMs.

Phase behavior of aqueous mixtures of 2-phenylbenzimidazole-5-sulfonic acid and cetyltrimethylammonium bromide: hydrogels, vesicles, tubules, and ribbons.

We studied the phase behavior and aggregation in mixed aqueous solutions of the anionic UV-absorber 2-phenylbenzimidazole-5-sulfonic acid sodium salt, PhBSA (Na salt), and the cationic surfactant cetyltrimethylammonium bromide, CTAB. The mixtures of the two components behave similarly to catanionic surfactant mixtures. The samples on the PhBSA-rich side have low viscosity and are turbid. The turbidity, due to uni- and multilamellar vesicles (SUVs and MLVs), increases with the mole ratio of CTAB. The interbilayer distance inside the MLV changes with the mole ratio of the two components from a few 10 nm for the 7:3 (molar ratio of PhBSA, Na salt, to CTAB) system to practically zero for the 5:5 mixture. The latter mixture forms a precipitate within less than 1 h. With the exception of the 5:5 mixture, all samples on the PhBSA-rich side are stable for many days. After that period, within one more day, the turbid vesicle phases are transformed into more or less clear hydrogels. We found that the gelation is due to the formation of very long stiff tubules about 14 nm in diameter, which is independent of the mixing ratio of the samples. The hydrogels and the tubules melt around 45 degrees C. On the CTAB-rich side, the 4:6 sample behaves like the 6:4 sample, whereas at 3:7 a precipitate was found to form shortly after mixing. At still smaller PhBSA (Na salt) to CTAB ratios, only clear, viscoelastic solutions are found that do not change with time. We determined the micellar structures in the samples by cryo-TEM and by SAXS. The rheological properties of the hydrogels and of the viscoelastic samples were characterized by oscillating rheological measurements. DSC measurements indicated that the tubules are in a semicrystalline state and melt at around 45 degrees C. The semicrystalline bilayer of the tubules seems to have a 1:1 composition of PhBSA to CTAB. The excess PhBSA seems to be adsorbed on the tubules. It is assumed that the stiffness of the bilayer of the vesicles and the stiffness of the tubules are due to the stiffness of the PhBSA molecule.

Millisecond-range time-resolved small-angle x-ray scattering studies of micellar transformations.

The transformation of mixtures of cationic and anionic micelles to vesicles has been studied by time-resolved small-angle x-ray scattering (SAXS). Equimolar amounts of ionic surfactant solutions, the anionic TexaponN70-H and the cationic TTAOH, were mixed by a stopped-flow device. Time-resolved SAXS patterns reveal that within the mixing time (<10 ms) mixed micelles are formed. These globular micelles dissolve within about 400-1000 ms and form monodisperse unilamellar vesicles in a much slower process of 5-100 s duration.

Sodium and Calcium Laurylamidomethylsulfate: Aqueous Micellar Phases, Their Properties, and a Precipitate of Vesicles.

A new anionic surfactant (M-LAMS) that is capable of forming intermolecular hydrogen bonds was investigated. Inverse solubilities of Na and Ca salts were found. Critical micelle concentration and aggregation behavior were determined by surface tension, light scattering, electric birefringence, and SANS measurements. It is found that the Na salt forms globular micelles while the Ca salt forms rodlike micelles. The phase behavior of the micellar solutions with increasing cosurfactant concentration was also studied. It is observed that 100 mM Na-LAMS solutions in the presence of 100 mM CaCl(2) undergo several phase transformations with increasing n-hexanol concentration. We found not only the expected micellar L(1) phase and a lamellar phase at concentrations quite low for this kind of system, but also a novel phase: At a cosurfactant/surfactant ratio x(C) of 1.2 a white precipitate is formed at the bottom of the sample. With increasing ratio x(C) the precipitate dissolves into a liquid crystalline L(alpha) phase that at x(C)=3.2 is transformed into an L(3) or sponge phase. Investigation by FF-TEM, light microscopy, and SANS shows that the precipitate consists of agglomerated polydisperse multilamellar vesicles. The vesicles consist of densely packed bilayers that contain little water. The bilayer thickness is about 20 Å and independent of its composition whereas the interlamellar distance is strikingly linked to concentrations of cosurfactant (surfactant/cosurfactant ratio) and electrolyte. With increasing cosurfactant content, the bilayers become less rigid and resulting thermal undulations force the membranes apart and weaken their interactions until a common L(alpha) phase is formed. This transition is an example of a bonding-nonbonding transition of membranes. Copyright 2001 Academic Press.

Empyema after pneumonectomy--empyema window or thoracoplasty?

369 pneumonectomies carried out within the years 1981 to 1988 and their empyema complications form the basis for a retrospective analysis to assess the outcome of treating pneumonectomy cavity empyema by window healing. During the same period 31 empyema after 322 pneumonectomies to treat bronchial carcinoma are investigated in more detail as far as their therapeutic modalities are concerned. 20 patients received a thoracic window. 18 of 31 patients (58%) could be cured, and 9 of these were in the thoracic window group. The hospital mortality of empyema patients after pneumonectomy amounted to 42%. In an historical comparison no progress could be recognized in the treatment of this septic complication.

[Endometriosis externa thoracalis]. / Beitrag zur Endometriosis externa thoracalis.

The incidence of endometriosis is between eight and 15 percent among sexually mature women, with peaks being in the third and fourth decades of age. External thoracic endometriosis is associated with implantation of endometrial tissue into lung, pleura, bronchial system, and diaphragm. Major indicators symptoms of thoracal endometriosis include haemoptysis, thorax pain, recurrent spontaneous pneumothorax, and haemorrhagic pleural effusion, with all these manifestations being temporally coordinated with menstruation. Bronchoscopy and radiography are used for diagnosis, while surgery, hormonal treatment, and radiotherapy are used for therapeutic action. One patient with systemic endometriosis is reported in greater detail in this paper.

[Generalized endometriosis]. / Generalisierte Endometriose.

Authors report on a case of generalized endometriosis. A 29 years old patient suffered from a primary amenorrhea by reason of an aplastic uterine cervix and an incomplete vaginal aplasia. Endometriosis has been ascertainable histologically in the uterus, in the left tube, near the gall bladder and in the pleura.

[Bifurcated resection in the surgical treatment of central non-small cell T3 carcinoma]. / Die Bifurkationsresektion in der chirurgischen Behandlung zentraler nichtkleinzelliger T3-Karzinome.

Reported in this paper is experience obtained since 1978 from surgical removal of the tracheal bifurcation in combination with pneumonectomy in 38 cases. Squamous cell carcinoma centrally growing from the upper lobe was recorded from 24 patients to whom 36 interventions had been applied for bronchial carcinoma. 50 per cent of all operations in conjunction with pneumonectomy were performed on patients in the pT3NOMO stage. The cumulated 3-year survival rate amounted to 37 per cent. Mortality in hospital accounted for 18.4 per cent and was thus clearly higher than what had been recordable from standard techniques in carcinoma surgery. Causes of postoperative deaths included insufficient sutures in three cases, pulmonary embolism in 2, and pneumonia in the contralateral residual lung in another 2. Standardised surgical and anaesthesiological techniques were used. Modifications of resections are discussed.

[Regional metastasis of bronchial cancer and therapeutic consequences. A contribution to the problem of the prognostic effectiveness of lymphadenectomy]. / Die regionale Metastasierung des Bronchialkarzinoms und ihre therapeutischen Konsequenzen. Ein Beitrag zur Frage der prognostischen Wirksamkeit der Lymphadenektomie.

In 1003 patients suffering from bronchial carcinoma the authors examined the type of lymph node spread. Radical lymph nodeectomy takes 30 to 60 minutes more without increasing the survival time, only the rate of regional metastases is diminished. The fate of the patient is dependent on the spread of haemotogenous micrometastases. According to the authors opinion simple extirpation of the regional lymph nodes as an en-bloc-procedure will be sufficient.