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Biomedical subjects

I Varga

Publications and source records attributed to I Varga.

At least 37 records · Page 2Linked to original sources

Electron microscopic and molecular identification of Wolbachia endosymbionts from Onchocerca lupi: implications for therapy.

It was recently demonstrated that Wolbachia intracellular bacteria (alpha 2 proteobacteria, Rickettsiales) living in filarial nematodes are obligatory symbionts of their hosts. Herein, we report the electron microscopic and 16S ribosomal DNA-based (16S rDNA) identification of the endobacteria harboring in Onchocerca lupi. The worm nodules containing the nematodes were removed from three Hungarian dogs naturally infected with O. lupi. Wolbachia-like endobacteria were detected by electron microscopy in the lateral chords of both adult worms and microfilariae. The endosymbionts in O. lupi resemble in location, size, and morphology the wolbachiae found in other filariae. The presence of wolbachiae in O. lupi was also confirmed by PCR amplification of the 16S rDNA of the bacteria. The 16S rDNA-based phylogenetic analysis revealed that the endosymbionts of O. lupi infecting dogs belong to the supergroup C of Wolbachia pipientis and are not identical with those of other Onchocerca spp. sequenced so far. Since intermittent treatment with oxytetracycline has adulticid and microfilaricid activity by depletion of Wolbachia endobacteria, this antibiotic treatment regimen may offer an alternative of ivermectin or diethylcarbamazine in the suppression of postoperative microfilaridermia in Onchocerca-infected dogs and may prevent relapse.

Animals↗

Induction of heat shock proteins fails to produce protection against trypsin-induced acute pancreatitis in rats.

Heat shock proteins (HSPs) are necessary in the synthesis, degradation, folding, transport, and translocation of different proteins. It is well known that the increased expression of HSPs may have a protective effect against cerulein-induced pancreatitis in rats or against choline-deficient ethionine-supplemented diet model pancreatitis in mice. The aim of this study was to investigate the potential effects of HSP preinduction by cold or hot water immersion on trypsin-induced acute pancreatitis in rats. Trypsin was injected into the interlobular tissue of the duodenal part of the pancreas at the peak level of HSP synthesis, as determined by Western blot analysis. The rats were sacrificed by exsanguination through the abdominal aorta 6 h after the trypsin injection. The serum amylase activity, the tumor necrosis factor-alpha, interleukin-1, and interleukin-6 levels, the pancreatic weight/body weight ratio, and the pancreatic contents of DNA, protein, amylase, lipase, and trypsinogen were measured. A biopsy for histology was taken. Hot water immersion significantly elevated the HSP72 expression, while cold water immersion significantly increased the HSP60 expression. Cold water immersion pretreatment ameliorated the pancreatic edema in trypsin-induced pancreatitis, however this was not due to the HSP60. Hot water immersion pretreatment did not have any effect on the measured parameters in trypsin-induced pancreatitis. The findings suggest that the induction of HSP60 or HSP72 are not enough to protect rats against the early phase of this localized necrohemorrhagic pancreatitis model.

Amylases↗

Subconjunctival zoonotic onchocerciasis in man: aberrant infection with Onchocerca lupi?

In the past few decades, 10 cases of cryptic, zoonotic onchocerciasis, including two subconjunctival infections, have been reported in man. In the majority of cases, Onchocerca cervicalis, O. gutturosa or O. dewittei, which normally infect horses, cattle and wild boar, respectively, were responsible for the lesions. However, the taxonomic status of the parasites involved in the two subconjunctival infections, both of which were European, has never been unambiguously determined. In such infections, the acute phase appears to be characterized by conjunctivitis. A single, strongly coiled, immature, female worm was found incorporated in a large granulomatous nodule, in the ocular and peri-ocular tissues, in the chronic stage of each of the two eye infections. Several, patent, sporadic cases of subconjunctival O. lupi infection have recently been reported in dogs. In terms of the location of the worms, clinical signs and histopathology, these canine infections were very similar to those seen in the two human patients with eye infection. When the parasites recovered from human eyes were compared morphologically with the Onchocerca spp. infecting animals in Europe, they appeared to be most similar to O. lupi. Although O. lupi is normally a parasite of dogs, it may thus also be responsible for aberrant, zoonotic, subconjunctival infections in man.

Animals↗

Anticryptosporidial prophylactic efficacy of enrofloxacin and paromomycin in chickens.

Two battery tests were conducted to study the anticryptosporidial prophylactic efficacy of the 2 commercially available antibiotics, enrofloxacin and paromomycin. The efficacy of enrofloxacin was 52% at the recommended level, which could not be increased, using twice the recommended dose. At the recommended levels, paromomycin reduced the oocyst output of birds by 67-82%, showing the highest efficacy of all drugs tested against avian cryptosporidiosis thus far. Moreover, the patent period was shortened by 12-23%. The body weight gain of paromomycin-treated chickens was almost identical with that of uninfected, untreated control birds irrespective of dosage, indicating the lack of toxicity. Although paromomycin is not registered for use in birds, in combination with sanitary procedures and disinfection, it may help in the control of cryptosporidiosis in some bird facilities.

Animals↗

Polyphasic typing of Cryptosporidium baileyi: a suggested model for characterization of cryptosporidia.

The present study was undertaken to characterize the oocyst morphology, host specificity, organ location, virulence, and sequences of the small subunit ribosomal RNA, 70-kDa heat shock protein, and oocyst wall protein genes of Cryptosporidium baileyi, and to compare this strain with other Cryptosporidium species. This study also aims to serve as a model for polyphasic (phenetic and genetic) characterization of Cryptosporidium species and strains. On the basis of these results, further genetic and phenetic characterization of an avian isolate is needed if the difference between the length or width, or both, of oocysts of an isolate and of C. baileyi is > or = 10% or if the difference between the oocyst shape index of the isolate and of C. baileyi is > or = 3% (or both). The isolate is infectious for mammals or lower vertebrates, or the host range is narrow, i.e., infectious only for some bird species; after oral or intratracheal inoculation, the parasites are not located in the cloaca and in the bursa of Fabricius or the respiratory tract; clinical disease or weight gain reduction can be observed after oral inoculation; the genetic distance for the examined gene between C. baileyi and the isolate is similar in magnitude to that observed between most closely related Cryptosporidium species.

Animals↗

Histidine decarboxylase deficiency in gene knockout mice elevates male sex steroid production.

Histamine is synthesized in cells by histidine decarboxylase (HDC). HDC-deficient knockout (KO) mice lack functional HDC and histamine in the tissues. In the present study we used this in vivo model for studying the role of HDC deficiency in the regulation of male steroid hormone metabolism. In agreement with earlier studies showing the lack of effects of central histamine on the basal secretion of gonadotrope hormones, we found no difference with in situ hybridization in the expression of GnRH in the hypothalamus of wild type and KO mice. The tissue concentrations of testosterone and several androgenic steroids were significantly elevated in the testes but not in the adrenal glands of HDC-KO mice. In contrast, serum estradiol levels failed to show a significant difference between the two groups. The weight of the testes was significantly smaller in both 7-day-old and adult KO mice. The ultrastructure of the adult testis indicated elevated steroid synthesis with more tightly coiled membranous whorls in Leydig cells. The present results suggest that changes in reproductive functions and sex steroid secretion in male HDC-KO mice are not due to altered hypothalamic GnRH expression but are probably related to definite modifications during fetal development of KO mice reinforced later by the lack of the effect of peripheral histamine. This may provide in vivo evidence that peripheral histamine is an important regulatory factor of male gonadal development during embryogenesis and of sex steroid metabolism later in adulthood.

Adrenal Glands↗

Morphologic and genetic characterization of Onchocerca lupi infecting dogs.

In the past decades, sporadic cases of ocular Onchocerca infection have been reported in canids in US and Europe. The present study was undertaken to provide a detailed description of the morphologic characteristics of adults and microfilariae and to characterize the 5S ribosomal rRNA gene (5S rDNA) spacer sequences of Onchocerca lupi causing canine onchocercosis. The morphology of O. lupi is unique within the genus, and morphology based cluster analysis indicates that O. lupi is not closely related to the members of domestic cattle or horse clades occurring in North America and Europe. Similarly, the signature of the 5S rDNA spacer sequences of O. lupi does not resemble any other Onchocerca 5S rDNA spacer sequences including those of the members of domestic cattle or horse clades. The adult and microfilarial morphology and sequence signature supports the biological arguments that a distinct species, O. lupi and not O. lienalis, is responsible for canine ocular onchocercosis.

Animals↗

Ocular onchocercosis in dogs: aberrant infection in an accidental host or lupi onchocercosis?

Four adult dogs that had spent their entire life in Hungary, were found to be infected with filaroid nematodes of the genus Onchocerca. The morphology and location of the parasites as well as pathological lesions were similar to those described earlier in the one Hungarian and five US dogs. Only moderate morphological differences were noted between the adults of Onchocerca sp. infecting dogs and O. volvulus of man or O. lienalis of cattle. Nevertheless, the morphology of microfilariae of Onchocerca from dogs is unique within the genus. Their length was less than half the length of microfilariae of other Onchocerca spp. known so far. In addition to size differences, several characteristic morphological features were observed. The unsuccessful attempt to infect dogs with O. lienalis, the absence of O. volvulus and O. lienalis in endemic regions of canine onchocercosis, the different size, morphology, and location of the adults in dogs and cattle, the exceptionally small size and unique morphology of microfilariae of Onchocerca of canids indicate that a distinct species might be responsible for canine onchocercosis. Since the larval concentration in the skin was high (50-3600 microfilariae g(-1)) in all affected dogs, the diagnosis prior to surgical removal of worm nodules can be based on the examination of a small skin snip collected from the head or abdominal region. Infections in dogs may provide a model to study human onchocercosis, therefore, further studies are encouraged on the feasibility of experimental infection of dogs with this Onchocerca species.

Animals↗

Canine ocular onchocercosis in Hungary.

An adult male mongrel dog that had spent its entire life in Hungary, was found to have infection with filaroid nematodes of the genus Onchocerca. The gravid male and female parasites were embedded in bean-sized granulomatous masses on the conjunctiva and the sclera of both eyes. The cuticle of females consisted of two separated layers in longitudinal sections, the external layer bearing ridges and the internal layer showing striations. The ridges were marked, rounded in shape, and the ratio of body diameter to the distance between ridges varied between 7:1 and 10:1. At midbody of the worms, two striations could be seen between each pair of ridges: one under every ridge and one between neighbouring ridges. Numerous exceptionally small (96.4 microm x 6.4 microm) microfilariae were seen in the uteri of females and the surrounding tissues and isolated from skin biopsy materials. The morphology and location of the parasite and histopathological lesions of the Hungarian case were similar to that described in dogs in the United States. This case is the first documented ocular Onchocerca infection in dogs outside the western United States. Thus, onchocercosis should be considered in the differential diagnosis of ocular and periocular nodules in dogs also in Europe.

Animals↗

Ivermectin toxicosis in a chameleon (Chamaeleo senegalensis) infected with Foleyella furcata.

Both male and female Foleyella furcata were found in the subcutaneous tissue and abdominal cavity of an adult male wild-caught Senegalese chameleon (Chamaeleo senegalensis). This nematode species is endemic to Madagascar but has never been recorded from the continent of Africa. Prior to the chameleon's death, a migrating worm was seen under the skin in the abdominal and thoracic region. Huge numbers of small, sheathed microfilariae were detected in the blood smears. The chameleon was treated with a single dose (0.2 mg/kg s.c.) of ivermectin. Serious adverse reactions (complete inertia) developed within 24 hr after injection and lasted for 7 days, indicating either ivermectin toxicity or a systemic reaction involving the release of endotoxins from the microfilariae dying in the bloodstream as a result of parasiticide therapy. Therefore, ivermectin treatment of chameleons infected with Foleyella should be avoided.

Animals↗

[Perspectives of laparoscopy in cardia and gastric surgery].

The authors have made 171 laparoscopic operations in the gastro-esophageal region during the past three and a half years. They have used the achievement of the minimal invasive surgery mainly in the treatment of functional diseases of the gastro-esophageal junction. Besides the hiatal reconstruction and antireflux procedures (142), endoscopic assisted cysto-gastrostomy (7), endoscopic assisted double-lifting gastric wall resection (5), cardiomyotomy (4), Graham suture of perforated duodenal ulcer (4) and enucleation of gastric wall leiomyoma (2) has been performed. There was no postoperative death, the rate of conversion was altogether 4.7% (8/171) while there was no need for reoperation in the early postoperative period.

Adolescent↗

[Beneficial effects of exogenous NO donors on morphologic changes induced by long-term administration of NO synthase blockers].

Nitric oxide represents an important mediator which is involved in a variety of cardiovascular functions. The goal of this work was to study the effect of long term NO synthase inhibition on the structure of conduit arteries. The second objective of this work was to determine whether changes in conduit arteries evoked by long term NO synthase inhibition could be prevented by concomitant delivery of exogenous NO. Two independent experiments (A, B) were performed. Both consisted of three groups of 10-week-old Wistar rats: (1) controls, (2) treated by L-NC-nitroarginine methyl ester (L-NAME) in water (50 mg/kg), and (3) in experiment A treated by L-NAME (50 mg/kg in water) + pentaerythrityetetranitrate (PETN) (2 x 50 mg/kg, using gavage), (3) in experiment B treated by L-NAME (50 mg/kg in water) + molsidomine (2 x 50 mg/kg, using gavage). Blood pressure (BP) was measured in all groups by the tail plethysmogrphic method. After 6 weeks the rats were killed and perfused by the glutaraldehyde fixative under the pressure equal to the control systolic blood pressure of 120 mmHg. Thoracic aorta, carotid artery and coronary artery were processed according to the standard electron microscopy procedure. Wall thickness (WT), cross sectional area (CSA), and inner diameter (ID) of the arteries were measured in light microscopy. A significant increase in BP, WT, CSA and WT/ID ratio (all p < 0.01) were observed after L-NAME administration in arteries, except of WT/ID in the coronary artery in experiment A where the increase was not significant. ID changed not. Administration of PETN or molsidomine to L-NAME treated rats resulted in a significant decrease in BP, WT, and CSA. The decrease in WT/ID in coronary arteries was present however not significant in experiment A. The inner diameter was significantly increased only in the thoracic aorta in experiment A. In summary, long term NO synthase inhibition evoked considerable morphological changes in the arterial wall of conduit arteries. The replacement of endogenous NO deficiency using exogenous NO donors resulted in a considerably beneficial effect in all parameters studied. (Fig. 4, Ref. 54.)

Animals↗

Preparation of indium-115-labeled diethylenetriaminetetraacetic acid monoacetamide peptides purified by 8-hydroxyquinoline.

In this communication we describe a novel procedure for the preparation and purification of diethylenetriaminepentaacetic (DTPA)-acylated and (115)In(3+)-labeled oligopeptides using 8-hydroxyquinoline for the removal and quantification of nonbound indium ions. First the N(alpha)- or N(alpha),N(epsilon)-DTPA oligopeptides containing C-terminal KDEL signal motif were produced by solid-phase synthesis. For this the free carboxyl group of DTPA dianhydride was activated in situ for a short period of time yielding a major product. Reversed-phase HPLC-purified DTPA oligopeptides were labeled with (115)In(3+) in aqueous buffer solution at pH 3.8. For the removal as well as for the detection of uncoordinated (115)In(3+) ions we have utilized the (115)In(3+) complex-forming ability of 8-hydroxyquinoline in chloroform. Following an optimized extraction procedure the free indium ion content was measured by spectrophotometry in the organic phase. Data obtained by this method and verified by total-reflection X-ray fluorescence spectroscopy and thin-layer chromatography demonstrated that free (115)In(3+) could be efficiently removed and sensitively detected in the presence of DTPA oligopeptide chelator. No release of (115)In(3+) from its DTPA complex was observed. This method could be useful for the preparation of indium complexes of peptides and perhaps proteins containing a DTPA moiety and nonradioactive isotope ligand.

Buffers↗

Influence of in ovo administered Cryptosporidium baileyi oocyst extract on the course of homologous infection.

In order to evaluate the effect of in ovo vaccination on avian cryptosporidiosis, two doses (1 and 10microg) of Cryptosporidium baileyi oocyst extract (OE) were injected into the amnionic sac of embryonated, specific pathogen-free chicken eggs. After hatching these birds as well as infected controls (IC) were inoculated with 8x10(5) C. baileyi oocysts at 10 days of age. Another group of chickens remained uninfected (UC). Faecal oocyst shedding was measured every second day, and weekly ELISAs were performed to monitor seroconversion. Those chickens that received OE during embryogenesis showed dose-dependent shift in their oocyst shedding, with higher oocyst output of OE1 and OE10 birds compared to IC ones. The patency was significantly longer in the OE10 group than in IC or OE1. ELISA results showed low seroconversion of OE1 and OE10 chickens prior to homologous challenge. Challenge infection resulted in antibody levels without significant difference between IC, OE1 and OE10 groups. These data suggest that in ovo vaccination with C. baileyi oocyst extract does not promote immune response, moreover, it may impair immunity and thus delay the clearance of cryptosporidia from chickens.

Animals↗

Cryptosporidiosis in birds--a review.

The morphology, life cycle, maintenance, host specificity, incidence of Cryptosporidium species infecting birds, as well as the epidemiology, clinical signs, pathology, immunology, diagnosis, therapy, and control of avian cryptosporidiosis are reviewed. Based on the accepted criteria used for differentiation of Cryptosporidium isolates into valid species, this review places the validity of C. meleagridis in doubt and suggests that C. meleagridis isolated from birds is very closely related to, or identical with C. parvum infecting more than 100 species of mammals.

Animals↗

New human Dirofilarioses in Hungary.

About ten cases of filariosis have recently been recorded in the Hungarian medical literature, six of them caused by Dirofilaria repens. Dirofilaria repensis a mosquito-transmitted filaroid worm in the subcutaneous tissue of dogs and cats in the temperate areas of the Old World. It accidentally infects man, too, and can remain unidentified due to physicians, poor knowledge of the parasite. In the last two years six new Dirofilaria repensinfections have been found in various parts of the country: five localised dermally and one in the deep tissues. Two of the cases might have been acquired in Italy during summer travels. Four patients, however, have never been abroad, these cases must be considered autochtonous infections. The thickness of the multilayered cuticle of the worm, diameter of the body and the size, form and number of the longitudinal ridges on its surface are used in the histological diagnosis of the the parasite.

Adult↗

Comparative analysis of plasma 17-hydroxyprogesterone and cortisol responses to ACTH in patients with various adrenal tumors before and after unilateral adrenalectomy.

Patients with non-hyperfunctioning adrenal adenomas often have an increased plasma 17-hydroxyprogesterone response to ACTH stimulation. The effects of adrenal surgery on this abnormality have rarely been investigated. One hundred and sixty-one patients with unilateral adrenal tumors (non-hyperfunctioning adenomas, 78; cortisol-producing adenomas, 8; aldosterone-producing adenomas, 37; adrenal cysts, 12; pheochromocytomas, 26) were studied. Patients before and after adrenal surgery as well as 60 healthy subjects underwent an ACTH stimulation test using 2 mg synthetic ACTH(1-24) (Cortrosyn Depot, Organon). Basal and ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations are reported. Before adrenal surgery, the basal plasma 17-hydroxyprogesterone concentrations were normal in patients with all types of tumors. However, the ACTH-stimulated plasma 17-hydroxyprogesterone levels were abnormally increased in 53% and 31% of patients with non-hyperfunctioning adenomas and aldosterone-producing adenomas, respectively. In addition, a few patients with adrenal cysts and pheochromocytomas also showed an increased ACTH-stimulated 17-hydroxyprogesterone response. After unilateral adrenalectomy, this hormonal abnormality disappeared in most, although not all patients with adrenal tumors. In patients with non-hyperfunctioning adrenal tumors, ACTH-stimulated plasma 17-hydroxyprogesterone and cortisol concentrations significantly correlated with the size of the tumors. These results firmly indicate that the tumoral mass itself may be responsible for the increased plasma 17-hydroxyprogesterone and cortisol responses after ACTH stimulation in patients with non-hyperfunctioning and hyperfunctioning adrenal adenomas.

17-alpha-Hydroxyprogesterone↗

[Atypical process of acute disturbance of liver function with severe thrombocytopenia in the third trimester].

The authors diagnosed disturbance of liver-function associated with severe thrombopenia in a pregnant woman in the third trimester. Principally, acute fatty liver of pregnancy can be characterized by existing symptoms, e.g. nausea, vomiting, epigastric pain, jaundice, hyperbilirubinemia, moderately elevated SGOT and SGPT levels, thrombopenia, leukocytosis, low fibrinogen level and disseminated intravascular coagulopathy, but hepatomegaly, purpura and petechia on lower and upper extremities, and high ALP and GGT levels during postpartum period do not confirm suspicion of this diagnosis. The present report draws attention to the difficulties of differential diagnosis of pregnancy-induced elevated liver enzymes diseases associated with low platelets, as there are several identical pathophysiological processes. Although causes and exact pathophysiology of disorders are unknown, similar symptoms during the process of diseases leave the question open whether they are different diseases or whether they are different manifestations of the same disease, and what kind of relationship exists between these diseases and preeclampsia. This case suggests careful evaluation of the whole clinical picture, moreover it is emphasized that prompt, aggressive treatment of hemostatic disturbance and the expeditious delivery can save maternal life.

Acute Disease↗