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Authors: J. Randerson, J. Moreau, T. Rigaud and Laurence D. Hurst

Within isopod crustaceans, the vertically transmitted bacteria Wolbachia induces either cytoplasmic incompatibility (CI) or feminization of male hosts. One of the challenges is to understand the distribution of the different manipulations between species. The invasion conditions for feminizers are much broader than for CI inducers and so the former is expected to be the more common, all else being equal. Here we ask whether prior infection with one type predisposes or inhibits the spread of a strain causing the opposite manipulation. Were this so, historical accident might have to be evoked to explain which species is affected by which type. We consider two possibilities. First, the appearance of a new mutant bacterium capable of both manipulations. Second, the appearance, via horizontal transfer, of a new bacterium capable of only one manipulation. In a mutational model, invasion of CI into a population with a feminizer is trivial, as is the reverse. This provides the first mechanism for trivial invasion of CI, but its biological relevance is unclear. In the horizontal transfer model, replacement of one type by another can occur if infection is initially into an uninfected lineage. However, under these circumstances neither form is likely to spread. If the initial horizontal transfer event is into an infected lineage, then under the most realistic circumstances, the prior existence of one form has little effect on the conditions for spread of the other, but may marginally inhibit or promote spread. If spread does occur, stable duel infection is the most common equilibrium condition. We suggest reasons as to why this has yet to be observed.

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A csontvelőben lévő mesenchymalis őssejtek multipotensek, kitűnő regenerációs készséggel rendelkeznek, sejtkultúrában nemcsak mesodermalis, hanem ectodermalis és endodermalis eredetű sejtekké is képesek differenciálódni. A regeneratív folyamatot bioaktív molekulák, speciális növekedési faktorok és vivőanyagok támogatják. A csontvelőben lévő mesenchymalis őssejtek jól felhasználhatók a sérült szövetek pótlásában és egyes betegségek gyógyításában. Az álízületek, csontdefektusok gyógyításában előnyösen alkalmazható a sejtes terápia, a csontvelőben lévő mesenchymalis őssejtekből megfelelő eljárással osteoblastok alakulnak ki. Ma már a klinikai alkalmazásról is vannak sikeres adatok. A sérült ízületi porc gyógyítása a csontvelőben lévő mesenchymalis őssejtek felhasználásával sikeresnek látszik a porcszövet regenerációjában. A kardiológia területén a myocardialis infarctus, továbbá a központi idegrendszer egyes betegségeinek és sérülésének gyógyításában számoltak be eredményes vizsgálatokról és klinikai alkalmazásokról. Vannak már biztató adatok máj- és vesebetegségekben, sérülésekben és a diabetesben történt alkalmazásról is. A közlemény célja, hogy áttekintse a közelmúltban végzett számos preklinikai vizsgálat során a mesenchymalis őssejtek molekuláris jellegzetességeit, az állatkísérletek során nyert eredményeket és a klinikai alkalmazás lehetőségeit. Orv. Hetil., 2012, 153, 1807–1815.

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Orvosi Hetilap
Authors: Anna Nagy, Orsolya Nagy, Enikő Bán, Eszter Molnár, Zsófia Müller, Márton Orbán, Borbála Kecskés, Emese Henriett Harsányi, Levente Kővágó, Lajos Jobbágy, Zoltán Németh, Zsuzsanna Várnai and Mária Takács

Rev. Anti Infect. Ther., 2015, 13, 327–342. 2 Kutasi, O., Bakonyi, T., Lecollinet, S., et al.: Equine encephalomyelitis outbreak caused by a genetic lineage 2 West

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A csontvelőből származó mesenchymalis őssejtek pluripotensek, s képesek porc, csont, valamint adiposus és ínsejtekké differenciálódni. Ezen mesenchymalis progenitor sejteket stromasejteknek vagy mesenchymalis őssejteknek nevezik. A csontvelőben két fő sejttípus van: haematopoeticus sejt és stromasejt. Mesenchymalis őssejtek kis beavatkozással nyerhetők a csontvelőből, majd sejtkultúrában szaporíthatóak. Differenciálódásuk bioaktív molekulákkal, specifikus növekedési faktorokkal segíthető elő. A transforming growth factor beta (TGF-β) család tagjai proteinek, közülük a bone morphogenetic proteinek (BMP) a legfontosabb faktorok, amelyek elősegítik a mesenchymalis őssejtek porc- és csontszövetté történő differenciálódását. Kevésbé ismert még ezen sejteknek a tenogenesisben való szerepe, de már vannak biztató adatok e téren is. A mesenchymalis őssejteknek és növekedési faktoroknak a sérült szövetekbe való juttatásra vivő vázanyagra (carrier, scaffold) van szükség. Mesenchymalis őssejtek használhatók fel génterápiára és a tissue engineering alkalmazására. A szerzők jelen munkájukban áttekintik a mesenchymalis őssejtek, biomolekulák és növekedési faktorok szövetpótlás céljából történő használatával foglalkozó kísérletes vizsgálatok eddigi eredményeit és ismertetik a klinikai alkalmazás lehetőségeit.

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Liver cells of the twenty-one day old rat embryo are isolated by a modified method and autophagy is studied in them by electron microscopic morphology and morphometry. Immediately after isolation or 2.5 h incubation in nutrient-free medium, embryonic hepatocytes contain high amount of glycogen and only very few autophagic vacuoles. In contrast, all glycogen is lost and 15% of the cytoplasmic volume is occupied by late autophagic vacuoles in hepatocytes after 18 h in the same medium. Presence of 3- methyladenine in the latter case inhibits both the loss of glycogen and the appearance of autophagic vac- uoles while enlarging the multivesicular body compartment. Our findings reveal major differences between isolated embryonic and adult hepatocytes concerning autophagy. Several types of autophagic vacuoles are described in the cell types of the erythropoietic cell lineage. This means that autophagy is an integral part of erythropoiesis not only in bone marrow, but also in embryonic liver that is investigat- ed here for the first time from this point of view. The presence of unclosed isolation membranes and the predominance of early autophagic vacuoles in reticulocytes indicates that the molecular machinery of segregation is still active in this functionally and structurally highly reduced cell type.

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Long polar fimbriae (Lpf) are recently discovered adhesins and increasingly important genetic markers of pathogenic Escherichia coli strains. The presence and genotype diversity of Lpf operons was screened in a collection of 97 Escherichia coli O157 strains representing different pathotypes, isolated from healthy cattle (n = 43) and human patients (n = 54) in several countries. Individual structural genes of Lpf were scanned by PCR, and allelic variants were detected with a recently developed typing scheme. Ninety-five strains carried at least one whole Lpf operon (genes lpf ABCD and/or lpf ABCDE). The 64 enterohaemorrhagic (EHEC) and 24 enteropathogenic (EPEC) strains all carried two Lpf operons, allele 3 of lpfA1 and allele 2 of lpfA2, a combination characteristic of the O157:H7/NM serotype. Out of the 9 bovine atypical (AT; stx-, eae-) strains, 7 carried one complete Lpf operon, allele 1 of lpfA2. The atypical strains belonged to main phylogenetic groups A and B1, while the EHEC and EPEC strains were from group D. Lpf variants carried by the 72 strains of the Escherichia coli Reference Collection (ECOR) were determined with the same typing scheme. Alleles were detected in 25 strains, of which 6 were found negative for the respective Lpf operons in earlier studies. The marker value of the Lpf allelic combination for the O157:H7/NM serotype was confirmed, and further evidence was given for the presence of at least two different genetic lineages of atypical bovine E. coli O157 strains.

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Acta Veterinaria Hungarica
Authors: Hakan Işidan, Turhan Turan, Mustafa Ozan Atasoy, Ibrahim Sözdutmaz and Bünyamin Irehan

The involvement of picornaviruses in calf diarrhoea was evaluated by the analysis of 127 faecal samples collected from diarrhoeic calves during 2014–2016. Virus detections were carried out by PCR using generic or specific primer pairs. One-third of the faecal samples (33.86%) were found to be positive for one or more of the studied viruses. Bovine kobuvirus was detected in 22.83%, bovine hungarovirus in 11.02%, while bovine enterovirus 1 in 5.51% of the samples. The sequences of the PCR products indicated the existence of novel variants in all the three virus species. When comparing the partial sequences, the nucleotide sequence identities between our newly detected viruses and those previously deposited to the GenBank ranged between 76 and 99%. Phylogenetic analyses revealed a novel lineage within the species Hunnivirus A. Our findings suggest that these viruses should be regarded as possible aetiological agents of calf diarrhoea. Based on the newly determined sequences, we designed and tested a new generic PCR primer set for the more reliable detection of bovine hungaroviruses. This is the first report on the molecular detection of the presence of bovine hungarovirus, bovine kobuvirus and bovine enterovirus 1 in the faecal samples of diarrhoeic calves in Turkey.

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Acta Veterinaria Hungarica
Authors: Sirintra Sirivisoot, Patharakrit Teewasutrakul, Somporn Techangamsuwan, Sirikachorn Tangkawattana and Anudep Rungsipipat

Heteroduplex polymerase chain reaction for antigen receptor rearrangements (hPARR) was developed to monitor minimal residual disease (MRD) in canine B- and T-cell lymphomas treated with the modified L-COP or L-CHOP protocol. Thirty-five dogs were recruited in this study and their neoplastic lineages were determined by immunophenotyping with Pax5 and CD3. Peripheral blood leukocytes were collected prior to and during chemotherapy in weeks 4, 9 and 13 to detect MRD by hPARR. Twenty-eight dogs (80%) had B-cell lymphoma while seven dogs (20%) had T-cell lymphoma. A monoclonal band was detected in 11 cases that showed complete or partial remission before tumour relapse and no response to the current treatment without statistical difference in clinical outcomes; however, the treatment response had an association with the MRD result (P < 0.05). Modified L-CHOP prolonged median progression-free survival as compared to modified L-COP (215 days vs. 93 days; P < 0.05). Substage b had shorter progression-free survival than substage a (90 days vs. 215 days; P < 0.05). Clinical stage III affected median overall survival time when compared to clinical stages IV and V (432, 173 and 118 days, respectively; P < 0.05). hPARR could be used for screening refractory lymphoma together with lymph node measurement in routine clinical cases.

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Acta Veterinaria Hungarica
Authors: Sanja Srzentić Dražilov, Janko Mrkovački, Vesna Spasovski, Amira Fazlagić, Sonja Pavlović and Gordana Nikčević

Mesenchymal stem cells (MSCs) hold enormous potential for cell-based therapy in the treatment of various diseases, particularly those which currently cannot be cured and result in poor outcomes or invasive surgery. Here we present results of the application of autologous, culture-expanded, adipose tissue (AT)-derived MSCs for the osteoarthritis (OA) treatment of 10 canine patients. The stemness of isolated cells has been confirmed by their ability to differentiate into osteo- and chondrocytic lineages. The clinical effect of a single injection of ATMSCs into the symptomatic joints was evaluated by a veterinarian for five disabilities characteristic of OA at 30, 60 and 90 days after treatment, which has been designated as the initial evaluation period. Functional outcomes for all analysed characteristics improved significantly at the end of this evaluation compared with the baseline. In addition, for 5 of these 10 patients, an extended follow-up study was performed from 1 to 4 years after the initial evaluation period. We detected long-lasting positive effects on two out of five analysed characteristics. The results demonstrate that the use of autologous AT-MSCs is a successful approach to canine OA therapy.

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Acta Veterinaria Hungarica
Authors: P. Gómez-Ochoa, F. Miana-Mena, M. Muñoz, M. Gascón, J. Castillo, E. Cativiela and F. Gómez

Pluripotent stem cells (PSCs), already described in human beings, are fibroblast-like cells that exhibit a CD34 marker specific for haematopoietic stem cells. In this work we have demonstrated the presence of PSCs in the peripheral blood of pigs, a species frequently used in transplantation studies as an animal model for human diseases. Differentiation into haematopoietic colonies (granulomacrophagic colonies, erythroid colonies and mixed colonies) has been carried out with the peripheral blood of adult and newborn pigs, using solely human commercial media. Peripheral blood mononuclear cells (PBMNCs) were cultured in semisolid methylcellulose based media enriched with recombinant human cytokines, achieving granulomacrophagic-colony forming unit (GM-CFU) and mixed-colony forming unit (Mix-CFU) growth with erythroblastic lineage proliferation in the presence of erythropoietin (Epo). In all the samples CFU growth was associated with the presence of recombinant human cytokine. No evidence of proliferation in control plates without cytokines was found. From liquid medium culture, a population of macrophages and CD34+ fibroblast like cells were retrieved 21 days after sowing. These findings allow us to think about the direct application of this simple and standardised method in several work fields such as the study of pharmacological effects of many drugs over the haematopoietic line and in the study of new strategies in cellular therapy for some human diseases.

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