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K Molnár

Publications and source records attributed to K Molnár.

At least 55 records · Page 3Linked to original sources
PubMed1998

Lucionema balatonense gen. et sp. n., a new nematode of a new family Lucionematidae fam. n. (Dracunculoidea) from the swimbladder of the European pikeperch, Stizostedion lucioperca (Pisces).

A new nematode genus and species, Lucionema balatonense gen. et sp. n., is described from the swimbladder of the European pikeperch, Stizostedion lucioperca (L.), from Lake Balaton in Hungary; a new dracunculoid family Lucionematidae fam. n. is established to accommodate it. The hitherto monotypic family Lucionematidae shows affinities with the families Skrjabillanidae and Daniconematidae, differing from them mainly in having simple oesophagus without external oesophageal glands and the vulva situated near the middle of body; from the first family also in the absence of the buccal capsule and the bursa-like caudal alae in the male. The genus Lucionema gen. n. is characterized mainly by the presence of 8 cephalic papillae in two circlets, absence of spicules, presence of the copulatory plate, only 2 pairs of postanal papillae in the male, and by the distal part of the monodelphic uterus forming a posteriorly directed coil. The body length of L. balatonense females is 1074-1782 microns, that of the only available male 770 microns. A key to the families of the Dracunculoidea is presented.

Air Sacs↗
PubMed1998

Studies on the occurrence of actinosporean stages of fish myxosporeans in a fish farm of Hungary, with the description of triactinomyxon, raabeia, aurantiactinomyxon and neoactinomyxon types.

Actinosporean infection of the oligochaete fauna living in the mud and on the vegetation of fish ponds used for rearing common carp in polyculture was studied during a one-year survey at a fish farm in Hungary, located south of Budapest. Twenty-eight actinospore types were isolated from the oligochaetes Tubifex tubifex, Branchiura a sowerbyi, Limnodrilus hoffmeisteri, Nais elinguis, and Stylaria lacustris collected during the survey, which could be classified into the triactinomyxon, raabeia, aurantiactinomyxon and neoactinomyxon groups. Drawings depicting individual actinospore types are presented on plates and their characteristic dimensions have been summarised in tables. The prevalence and seasonality of actinosporean infections observed in the various oligochaete species have been illustrated graphically. Infection by actinospores showed a pronounced seasonality. In the spring, summer and autumn the prevalence of raabeia infection in Branchiura exceeded 90%, while in the winter it dropped to 42%. A similar phenomenon could be observed for aurantiactinomyxon infection, while neoactinomyxon infection reached its peak in the autumn. In Tubifex, Limnodrilus, Nais and Stylaria species the peak of actinosporean infection occurred, with minor differences, in the spring and summer. Actinosporean infection in the individual Oligochaeta species showed much higher prevalence values than had been reported in the literature, which can be explained by the novelty of the examination technique used. It cannot be decided with absolute certainty which myxosporean developmental stage the different actinospore types described during this survey represent of the species of Myxosporea parasitic in the given ponds. This would require an experimental study for which the data presented here may serve as a basis.

Animals↗
PubMed1998

Studies on the occurrence of actinosporean stages of myxosporeans in Lake Balaton, Hungary, with the description of triactinomyxon, raabeia and aurantiactinomyxon types.

In the framework of a one-year survey, the actinosporean infection of the oligochaete fauna living in the mud and on the vegetation of Lake Balaton, Hungary was studied. A total of 10 types of actinospores were isolated from the oligochaetes Tubifex tubifex and Limnodrilus hoffmeisteri collected during the survey, which could be classified into the triactinomyxon, raabeia and aurantiactinomyxon groups. The drawings depicting the individual actinospore types are presented on a plate and their characteristic dimensions summarised in tables. The prevalence and seasonality of actinosporean infections observed in the two oligochaete species are illustrated graphically. Infection by actinospores showed pronounced seasonality. In the spring and summer the prevalence of triactinomyxon infection in T. tubifex exceeded 30 and 40%, respectively, while in the autumn it dropped to 6%. In T. tubifex raabeia infection of 3% prevalence was detected only in the summer period. In L. hoffmeisteri the peak of aurantiactinomyxon, raabeia and triactinomyxon infection occurred in the summer with a prevalence of 21, 10 and 8%, respectively. Actinosporean infection in the individual Oligochaeta species showed higher prevalence values than had been reported in the literature, which fact may be explained by the novelty of the examination technique used. Four types of actinospores found in Lake Balaton are identical with the actinospores already described. It cannot be determined with absolute certainty which stages of myxosporeans parasitic in Lake Balaton fishes are identical with the 10 actinospores described.

Hungary↗
PubMed1998

Occurrence of skrjabillanid nematodes in fishes of Hungary and in the intermediate host, Argulus foliaceus L.

Histozoic and coelozoic skrjabillanid-type nematodes belonging to the genera Skrjabillanus, Molnaria, Sinoichthyonema, Esocinema, Daniconema and Lucionema are recorded from the subcutaneous tissues, fins, swimbladder and abdominal cavity of different fish species living in natural waters and fish farms of Hungary. In addition to the nine taxonomically identified parasite species, one Skrjabillanus sp., two Molnaria spp. and three Esocinema spp. were identified to the genus level only. The histozoic larval stages of a Molnaria, Daniconema and Lucionema species each, living in a site different from that of the imagoes, were also detected. The presence of closely not identified first- to third-stage skrjabillanid larvae was demonstrated in 26.3% of the parasitic carp lice (Argulus foliaceus L.) collected from the eight fish species.

Animals↗
PubMed1998

Taxonomic problems, seasonality and histopathology of Henneguya creplini (Myxosporea) infection of the pikeperch Stizostedion lucioperca in Lake Balaton.

Plasmodia of a Henneguya species measuring 70-900 microns and exhibiting season-dependent stages of development were detected throughout a three-year study on gill myxosporosis of Lake Balaton pikeperch (Stizostedion lucioperca (L.)). Sixty-five out of 160 fish (41%) examined in the period of study were infected by the parasite. Infection was the most prevalent (48%) among pikeperch specimens exceeding 40 cm in length. The highest prevalence of infection (58%) was recorded in 1995-1996 while the lowest (30%) in 1996-1997. The youngest plasmodia appeared in April, and started to develop within the capillaries of the secondary lamellae of the gill filaments. The round or ellipsoidal plasmodia which continued their gradual growth in the subsequent months of the year achieved a size of 800-900 microns by the late autumn months, but remained in intralamellar location throughout the developmental cycle. Mature spores developed in the plasmodia by the end of winter. On the basis of their shape and size, the spores were identified as Henneguya creplini (Gurley, 1894). However, because of the uncertain taxonomy of species assigned to the genus Henneguya the taxonomic position of the parasite requires further study. The host reaction consisting of epithelial proliferation and granulation tissue formation starts around the infected secondary lamella only after the maturation of spores and the disruption of plasmodia.

Animals↗
PubMed1997

Baculovirus-mediated trans-epithelial transport of proteins in infected caterpillars.

Baculovirus-mediated abnormal protein trafficking was studied in infected caterpillars by using heterologous proteins. The gene for human complement C1r was expressed in larvae of Mamestra brassicae by a recombinant Autographa californica nuclear polyhedrosis virus (AcMNPV) vector. By following the time-course of recombinant C1r distribution among various tissues, cell types and cell organelles, we concluded that the dominant site of recombinant protein synthesis was the fat body, although some production in the haemocytes and midgut was also observed. Only about 4% of the cells of the infected organs expressed recombinant C1r, which was then secreted into the haemolymph. The tracheal and integumental cuticle was rich in recombinant protein from the fourth day after infection although epidermal cells did not synthesize recombinant C1r. The morphological picture suggested that the accumulation was a consequence of a trans-epithelial transport. This transport process was checked by following the fate of the 49 kDa haemolymph protein and injected ovalbumin in AcMNPV-infected Mamestra brassicae and in Lymantria dispar nuclear polyhedrosis virus-infected Lymantria dispar larvae. Both proteins were able to pass the basal membrane of the epidermis and accumulated in the cuticle, while in control larvae neither was transported. The observed trans-epithelial transport points to the role of baculoviruses in directing recombinant, endo- and exo-genous proteins to cuticulated tissues. Based on these results we conclude that the permeability of basal membranes undergoes a characteristic change during the course of baculovirus infection.

Animals↗
PubMed1997

An unusual location for Ergasilus sieboldi Nordmann (Copepoda, Ergasilidae) on the operculum and base of pectoral fins of the pikeperch (Stizostedion lucioperca L.).

Ergasilus sieboldi infestation of the pikeperch (Stizostedion lucioperca) is extremely common in Lake Balaton. In the summer and autumn, these parasitic copepods have high prevalence and intensity on pikeperch of more than 20 cm body length. Typically, Ergasilus establish themselves in the folds on the external surface of the operculum and on the base of the pectoral fins, and only a small proportion cling to the gill filaments. Infestation is rare and of low intensity in pikeperch of less than 20 cm body length. The Volga pikeperch (Stizostedion volgense) has low-intensity infestation irrespective of age. The lesions caused by copepods present on the operculum are restricted to the epithelium even if infestation is intensive.

Animals↗
PubMed1997

Extrapiscine development of Myxobolus drjagini Akhmerov, 1954 (Myxosporea: Myxobolidae) in oligochaete alternative hosts.

The extrapiscine development of Myxobolus drjagini, a myxosporean parasite of the head, operculum and buccal cavity of the silver carp (Hypophthalmichthys molitrix), was studied in experimentally infected oligochaetes, Tubifex tubifex. After infection of uninfected tubificids with mature spores of M. drajagini, development of actinosporean stages was first observed by light microscopy 27 days after infection. Triactinomyxon stages of M. drjagini emerged from the worms after 91 days of intraoligochaete development. In histological sections, early pansporocysts were found in the gut epithelium of the experimental oligochaetes 42 days after infection. Mature pansporocysts, each containing 8 triactinomyxons, appeared 79 days after infection. After rupture of the epithelial cell and the pansporocyst, free actinosporean stages were found in the gut lumen of the oligochaete. Actinosporean stages released from oligochaetes appeared in the water 91 days after infection. They were floating in the water and showed a typical triactinomyxon form. Each triactinomyxon had three pyriform polar capsules, a sporoplasm with 14 secondary cells inside the spore body, a moderately long style and slightly bent, trifurcated, conically ending tails. The total length of the triactinomyxon measured approximately 198 microns. The prevalence of infection in 51 oligochaetes proved to be 9.8%. No infection was found in the control oligochaetes.

Animals↗
PubMed1996

[Food allergy in patients with chronic urticaria].

Basic food allergens (bread, milk and egg) were investigated in patients with idiopathic chronic urticaria. In 29 of 43 patients, sensitivity could be shown against one or more antigens. The results suggest not only the anaphylactic IgE-mediated reaction in same patients, but also an antibody or cell-mediated mechanisms in the development of the disease. Besides the Prick test, therefore, testing of other circulating antibodies by means of the ELISA technique and the leukocyte migration test is recommended to establish the causative agents in patients with chronic urticaria.

Adolescent↗
PubMed1996

Identification of different circulating autoantibodies in patients with bullous pemphigoid and pemphigus vulgaris by means of immunoblotting.

Immunoblotting studies with salt-split human epidermis were performed on sera from 15 patients with pemphigus vulgaris and 20 patients with bullous pemphigoid by using peroxidase-labelled antihuman IgG and IgA. Eleven sera of pemphigus vulgaris antigen. Most of the sera gave additional specific bands at 210 and 80 kD, with lower intensity. The sera of 4 patients, 3 of them were in clinical remission, did not yield specific bands. Seventeen sera of the 20 bullous pemphigoid patients yielded a 220-230 kD protein band against the major bullous pemphigoid antigen and 4 of them gave another specific band at 160-180 kD. Five sera produced multiple bands (220, 130, 100 and 75 kD). IgA antibodies against the major bullous pemphigoid antigen were demonstrated in 2 cases with IgA deposits along their basement membrane, as revealed by direct immunofluorescence. The immunoblot patterns correlated only weakly with the clinical findings in bullous pemphigoid. There was a considerable diversity in both clinical findings and immunoblot patterns.

Aged↗
PubMed1996

Remarks on the morphology, site of infection and validity of some coccidian species from fish.

The morphological identification of carpelli-type oocysts of Goussia species parasitizing the gut of different cyprinids is unreliable. Species similar in shape and size can be differentiated only by cross-infection experiments. Goussia scardinii (Pellérdy et Molnár, 1968), developing in the renal tubules of cyprinids, is a synonym of Goussia leucisci (Shulman et Zaika, 1964). The morphology and location hitherto assumed to be species characteristics of G. scardinii can be explained by the aging of oocysts and the type of host reaction. Eimeria rutili Dogiel et Bychowsky, 1938 is a coccidian parasite occurring in various organs of the roach. Its oocysts can be found in the blood vessels and, thus, also in the gill capillaries. Eimeria branchiphila Dyková, Lom et Grupcheva, 1983, described from blood vessels of the gills of the same fish species, should be regarded as a synonym of E. rutili. The Octosporella species described from fish are based on erroneous identification and should be considered nomina nuda. Similarly, the Eimeria and Isospora species described from fish by Davronov in 1987 should also be regarded as nomina nuda, as they appear to be avian or mammalian coccidia that entered the intestinal tract of fish with food. The sporocyst residua of fish coccidia cannot be used as characters suitable for species identification, as they tend to change with oocyst aging.

Animals↗
PubMed1996

Detection of bullous pemphigoid antibodies by means of synthetic peptides as antigenic epitopes.

In an earlier study, the circulating autoantibodies in patients with bullous pemphigoid (BP) were demonstrated in higher frequencies by means of an immunoblot technique then via indirect immunofluorescence. In the present work with the help of Peptide Structure software, two matched antigenic epitopes were chosen and synthesized. The sera of 34 patients with BP were investigated in parallel by an immunoblot technique using a human epidermal extract, and by an ELISA technique with synthetic peptides. The sera of 16 healthy persons and 10 patients with other bullous diseases served as controls. Among the 34 patients with BP, 23 sera proved positive for at least one synthetic peptide. Positive reactions with the major BP antigen (230 kD) were found in 22 patients by immunoblot technique and in 16 patients by the ELISA technique with the synthetic peptide, whereas with the minor BP antigen (180 kD), positive reactions were found in 9 patients by the immunoblot technique and 18 patients by the ELISA technique using the synthetic antigenic epitope of the minor BP antigen. All control sera were negative for both antigens in ELISA investigations. In 3 patients with pemphigus vulgaris, characteristic bands against pemphigus vulgaris antigen were identified by means of the immunoblot technique, but all other cases were negative. It is suggested that the development of this technique may lead to an opportunity for the rapid and simple diagnosis of BP.

Adult↗
PubMed1995

Redescription of Goussia neglecta n. comb. (Nöller, 1920) (Apicomplexa; Coccidia) and notes on its occurrence in the gut of tadpoles.

Coccidian infection in Rana ridibunda and R. esculenta tadpoles was recorded in Hungarian fish farms. Oocysts enclosed in yellow bodies were found in the faeces and in the intestinal epithelium. Developmental stages also had intraepithelial sites. The species was identified with Eimeria neglecta Nöller, 1920; however, on the basis of its oocyst morphology it was transferred to the genus Goussia. Besides stages of Goussia neglecta n. comb., intranuclear trophozoites of another coccidian species were also recorded.

Animals↗
PubMed1995

Effect of exposure to malachite green solution on common carp fry with Dactylogyrus vastator (monogenea) infection.

In five experiments, common carp (Cyprinus carpio) fry with Dactylogyrus vastator (Monogenea) infection of different severity, as well as parasite-free fry, were placed into aquaria containing malachite green solution of 0.5-10 mg/l concentration. Most of the fish died within 6 hours. The correlation between the time of death and helminth infection was studied. The experiments demonstrated that in malachite green solution the carp with the heaviest helminth infection died first while the less severely infected specimens survived for the longest time.

Animals↗
PubMed1995

Histological changes in the swimbladder wall of eels due to abnormal location of adults and second stage larvae of Anguillicola crassus.

In severe Anguillicola crassus infection of eels, adult helminths and 2nd stage larvae staying in the swimbladder lumen may occasionally get, through minor lesions of the tunica interna, into the subserosa of the swimbladder wall where they die and disintegrate. A thin connective tissue capsule is formed around the helminths that behave as foreign bodies in intercellular location, while the lacunas of the surrounding loose connective tissue comprise melanin-containing macrophages. In the environment of the 2nd stage larvae the formation of giant cells is a typical finding.

Air Sacs↗
PubMed1994

Dynamics of Anguillicola crassus (Nematoda: Dracunculoidea) infection in eels of Lake Balaton, Hungary.

Following the introduction of Anguillicola crassus into Lake Balaton, by 1991 the entire eel population became infected. At the same time, marked differences existed in the prevalence and intensity of infection between different areas of the lake. The highest prevalence values occurred in the eastern basin less densely populated with eels, while in the western basin a large proportion of the fish were free of infection. Helminth-free status accompanied by thickening of the swimbladder wall developed after intensive infections. In 1991, eel mortality could be observed only in the western basin. In 1992, the number of eels with swimbladders having a thickened wall but not containing helminths increased also in the central and eastern areas of the lake. Parallel to this, a mortality less expressed than the one in 1991 occurred in the central part of the lake. By 1993, a host-parasite equilibrium had become established in Lake Balaton.

Air Sacs↗
PubMed1994

Third-stage larvae of Daniconema anguillae (Nematoda: Dracunculoidea) in the subcutaneous tissue of eel Anguilla anguilla.

Daniconema anguillae Moravec et Køie, 1987 larvae measuring 1.64-1.76 mm were occasionally found in considerable numbers in the fins and subcutaneous connective tissue of approximately 50% of eel Anguilla anguilla (L.) sampled from Lake Balaton, Hungary. The larvae were noted for their slender body, very long tail with a rounded tip, a densely transversely striated cuticle, and the presence of boring tooth and large kidney-shaped amphids on the cephalic end. The larvae could easily be recovered from the above mentioned organs by placing them into isotonic saline solution. No disease signs or pathological changes attributable to the larval infection could be observed. The only histological indication of host reaction was the appearance of macrophages adhering to the body surface of larvae and of cells with spherical nucleus in areas around the larvae. A possible life cycle pattern of D. anguillae is discussed.

Anguilla↗