Biomedical subjects

E Kádár

Publications and source records attributed to E Kádár.

At least 19 recordsLinked to original sources

PubMed2006

Unidentified extracellular prokaryotes within the byssal threads of the deep-sea vent mussel Bathymodiolus azoricus.

Bacterial symbiosis and/or parasitism is widespread in hydrothermal bivalves, and is typically developed in gills, with a lower incidence in mantle and digestive glands, while it has never been described in byssus. Using ultrastructural examination, we provide evidence for the existence of a potentially new group of filamentous prokaryotic organism in Bathymodiolus azoricus byssus, with putative parasitic influence. Additionally, a cystic, undefined organism was found with an unclear physiological role within the spongy net of the byssus plaque. Our results indicate that in spite of its antibacterial protective sheath, byssus gives access to prokaryotic organisms becoming prone to failure through damaged collagen fibres.

Animals↗

PubMed2005

Effect of culture conditions on the obtention of boar epididymal epithelial cell monolayers.

The goal of this study was to investigate the effect of the collagenase digestion time, the initial density of fragments and the culture temperature on the obtention of a boar epididymal epithelial cell culture, which is a useful methodology for the study of epididymal functions. A confluent monolayer of caput, corpus and cauda epididymal epithelial cells was only obtained when an adequate enzymatic digestion of the connective tissue surrounding the epididymal tubule was performed. For the correct digestion of caput and corpus fragments two collagenase digestions of 2 and 1h, respectively, were enough. Cauda fragments, however, needed two collagenase digestions of 3h each. A confluent monolayer of caput, corpus and cauda epididymal epithelial cells was obtained regardless of the initial density tested (15, 30, 60 and 90fragments/well). However, cultures originated from 15 and 30fragments/well showed higher cell concentration during the first 2 weeks of culture than cultures originated from 60 and 90fragments/well. A confluent monolayer of caput, corpus and cauda epididymal epithelial cells was obtained at both 32 and 37 degrees Celsius, but at 32 degrees Celsius cells grew very slowly and confluence was not reached until a week later than it was with cells growing at 37 degrees Celsius. In conclusion, we have observed that the time of digestion with collagenase is an important factor for the successful establishment of boar epididymal cell monolayers, and that the initial density of fragments and the culture temperature should be taken into account.

Animals↗

PubMed2005

Evaluation of boar sperm maturation after co-incubation with caput, corpus and cauda epididymal cultures [corrected].

Boar sperm from the proximal caput epididymis were co-incubated with 1, 4, 7, 10 and 14-day old caput, corpus and cauda epididymal cultures for 24, 48 and 72 h. Boar kidney epithelial cells (LLC-PK1) and ECM alone were used as negative controls. Sperm motility, morphology and membrane integrity were studied to evaluate boar sperm maturation in vitro. Our results showed that epithelial cell monolayers (10, 14-day old) create a suitable microenvironment for the survival of proximal caput sperm and the maintenance of sperm motility over a 72 h period. Moreover, corpus epididymal tubule fragments in culture (1, 4-day old) are capable of promoting the migration of the cytoplasmic droplet along the sperm tail after 24h of co-incubation.

Animals↗

PubMed2004

Semen quality of postpubertal boars during increasing and decreasing natural photoperiods.

The present study analyses the effects of increasing and decreasing photoperiods on the semen quality of 20 selected postpubertal Landrace boars. The boars were exposed, throughout 75 days, to increasing and decreasing photoperiods of natural light, a constant temperature of 21 +/- 1 degrees C and 60-70% of humidity, fed with a nutritious diet and, submitted to a rhythm of semen collection of twice a week. During the last 2 weeks of each treatment, semen samples were analysed and the parameters measured were: ejaculate volume and pH, sperm concentration, sperm production and the number of semen doses per ejaculate, sperm vitality, sperm motility, osmotic resistance of spermatozoa and sperm morphology. The comparative analysis between increasing and decreasing photoperiods indicated that the semen quality of boars exposed to a decreasing photoperiod was reduced as a consequence of decreases in sperm concentration, sperm production and the number of semen doses. There was no difference between increasing and decreasing photoperiods in terms of sperm vitality and sperm motility, nor in the osmotic resistance of spermatozoa to isotonic and hypotonic media. The analysis of sperm morphology showed significantly lower frequencies of mature and immature spermatozoa with a distal cytoplasmic droplet, and significantly higher frequencies of immature spermatozoa with a proximal droplet in boars exposed to the decreasing photoperiod. These results indicate that the sperm quality of the selected boars decreased during decreasing photoperiods, in comparison with increasing photoperiods, mainly due to impaired testicular function.

Acrosome↗

PubMed2002

The cycle of the seminiferous epithelium in Landrace boars.

The present study describes the morphological features of the eight stages of the seminiferous epithelium in Landrace boars according to the tubular morphology method, as well as their relative frequency, length, and duration. In Landrace boars the pre-meiotic stages occupied the 31.9 +/- 19.9% of the spermatogenic cycle and had a total length of 1788.8 +/- 1153.0 microm and a duration of 2.78 days; they were mainly characterised by the presence of leptotene and pachytene spermatocytes and round spermatids. Meiotic stages, with a relative frequency of 16.4 +/- 6.8%, a length of 787.1 +/- 603.1 microm and a duration of 1.41 days, contained spermatocytes in advanced meiosis I and/or in meiosis II and elongating spermatids grouped in bundles. Post-meiotic stages occupied the 50.6 +/- 20.4% of the spermatogenic cycle and had a length of 2096.8 +/- 1175.0 microm and a duration of 4.37 days; the most important event of these stages was the spermiation, which included the complete remodelling of sperm head and tail and the releasing of spermatozoa into the lumen, as well as the formation of residual bodies. From data obtained we concluded that both germ cell associations of the stages maintain constant among Landrace boars, and that the relative frequency, length and duration of the stages were directly dependent of the cytological transformations on the seminiferous tubules.

Animals↗

PubMed2002

Myeloablation enhances engraftment of transduced murine hematopoietic cells, but does not influence long-term expression of the transgene.

To investigate to what extent myeloablation, graft size, and ex vivo manipulation influence the engraftment and long-term survival of transduced murine hematopoietic cells, groups of C57BL/6J (CD45.2) mice receiving total body irradiation (TBI) (1-9 Gy) or no irradiation were transplanted with either transduced bone marrow (BM) cells, at two cell doses, or with fresh BM cells from B6/SJL (CD45.1) congenic mice. Short (40 days) and long-term (5 months) engraftment and transgene expression were measured by FACS analysis. No donor cells were detected in the hematopoietic tissues of non-myeloablated mice, whereas in the irradiated animals, levels of engraftment correlated well with the dose of TBI administered. Similar percentages of transgene-expressing cells were found in the grafted hematopoietic cells of all groups of mice, regardless of the dose of TBI administered or the level of engraftment achieved. This suggests that the engrafted animals could become tolerant to the transgene product (enhanced green fluorescent protein, EGFP). Our results indicate that TBI facilitates the engraftment of manipulated hematopoietic cells in a dose-dependent manner, that mice engrafted with EGFP(+) hematopoietic cells probably acquire tolerance to EGFP, and that increasing the graft size and reducing the ex vivo manipulation required for retroviral gene transfer of hematopoietic cells also enhances their engrafting potential.

Animals↗

PubMed2001

Avoidance responses to aluminium in the freshwater bivalve Anodonta cygnea.

This study examined the effect of aluminium (Al) on the filtering behaviour (shell opening or gape) of the freshwater bivalve Anodonta cygnea L in neutral fresh water. Parallel measurements of Al concentration in the soft tissues were made to examine the relationship between changes in behaviour and accumulation of Al. The number of lysosomal granules in the gill, kidney and digestive gland were counted, as lysosomes are known to be involved in the excretion and detoxification of trace metals. The bivalves were exposed to two environmentally relevant concentrations of added Al i.e. 250 and 500 microg l(-1) (9.25 and 18.5 microM l(-1)) at neutral pH for 15 days and shell movement monitored continuously. Aluminium affected the mussels' filtering activity, producing an avoidance reaction whose magnitude was concentration-dependent; 250 microg l(-1) added Al produced no detectable change, while 500 microg l(-1) Al reduced mean duration of shell opening by 50%. This effect was irreversible over a 15 day recovery period. Tissue levels of Al after 15 days exposure were an order of magnitude higher in animals exposed to 250 microg l(-1) added Al than in those exposed to 500 microg l(-1). This was consistent with the inhibition of filtering activity due to valve closure at the higher concentration, which may have prevented uptake of Al. In addition, probable different chemical speciation of Al in the water column (soluble for 250 and colloidal for 500 microg l(-1)) may lead to marked differences in tissue uptake. The kidney and digestive gland were the main sites of accumulation of Al and concentrations remained significantly elevated 15 days after transfer of animals to clean water. It is suggested that mucus plays a role in the exclusion of Al as elevated concentrations were measured in the pseudofaeces of animals during and after exposure. Lysosomal granules may be involved in the intracellular handling and detoxification of Al as numbers increased significantly in all organs during exposure and continued to increase after the animals were transferred to clean water. The present study provides evidence for the bioavailability and toxicity of Al to mussels at neutral pH and at concentrations which are known to enter neutral freshwaters when mobilised by natural or anthropogenic acidity. The changes in behaviour and uptake of Al in the mussel observed in this investigation are, therefore, likely to be reflected in the natural environment and the degree to which Al affects the 'fitness' of the mussel populations and the transfer of Al through the food chain merit investigation.

Aluminum↗

PubMed1998

Effects of orotic acid on ischaemic/reperfused myocardial function and glycogen content in isolated working rat hearts.

The present study was carried out to investigate the effect of orotic acid on ischaemic/reperfused myocardial function and cardiac glycogen content in isolated working rat hearts. In a preliminary series of studies, hearts isolated from male Wistar rats (300-350 g) were perfused with oxygenated Krebs-Henseleit buffer containing cumulative concentrations of orotic acid from 0.01 to 10.00 mg l-1. In the concentration range of 0.01-0.10 mg l-1, orotic acid significantly improved left ventricular function. Therefore, in the second series of studies, rats were treated intravenously with 0.01 mg kg-1 orotic acid for 4 days. Hearts were then isolated and subjected to 30 min of global no-flow ischaemia followed by 10 min of reperfusion. Orotic acid treatment significantly improved post-ischaemic myocardial function and increased pre-ischaemic and post-ischaemic glycogen content of the heart. We conclude that orotic acid improves ischaemic/reperfused cardiac performance and this effect may be based on the elevation of myocardial glycogen content.

Animals↗

PubMed1998

Granulocyte colony-stimulating factor administered as a single intraperitoneal injection modifies the lethal dose95/30 in irradiated B6D2F1 mice.

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor that stimulates the proliferation of progenitor myeloid cells. We have previously demonstrated that recombinant human G-CSF (rhG-CSF) significantly improves survival of lethally irradiated B6D2F1 mice when administered as a single intraperitoneal dose of 1 mg/kg 2 hours after a lethal dose (LD)95/30 irradiation. In our model, rhG-CSF is also able to modify the LD95/30 in irradiated animals and 1.1 has been found to be the dose modification factor (the ratio of LD95/30 for mice treated with rhG-CSF to that for control animals).

Animals↗

PubMed1997

Serum levels of G-CSF, IL-3, IL-6 and GM-CSF after a single intraperitoneal dose of rhG-CSF in lethally irradiated B6D2F1 mice.

The objective of this study was to assess the pharmacokinetics of rhG-CSF after a single intraperitoneal injection 2 h post-TBI in B6D2F1 lethally irradiated mice and to analyze the effect of rhG-CSF on the endogenous response of interleukin-3 (IL-3), interleukin-6 (IL-6) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in these animals. For comparison, these cytokine serum levels have also been measured in nonirradiated mice. The serum concentrations of rhG-CSF in irradiated mice were higher than in nonirradiated mice at all time points during the first 60 min after injection. Furthermore, rhG-CSF administration failed to induce detectable endogenous serum levels of IL-3, IL-6 and GM-CSF, at least in the 72-hour period after administration of the rhG-CSF. The radioprotective effect of rhG-CSF in lethally irradiated mice is not mediated by an increase in endogenous serum levels of these three cytokines.

Animals↗

PubMed1997

The current surgical treatment of primary malignant melanoma of the skin.

In our Department, between 1991 and 1996, 132 patients, there of 87 male-45 female, average age of 48.2 years underwent surgery because of stage 1 (T2) to stage 3 melanoma that was located on the skin. None of patients suffered from early or in situ melanoma. Our retrospective study was based on those 94 patients who had been followed up by Department or dermatology-oncology in our medical centre. Surgery is still the primary treatment for cutaneous malignant melanoma. Thin melanomas (up to 2 mm in thickness) can be excised with 2 cm margins. Whether this is also true for thicker melanomas is not known and the only way to obtain more knowledge is to participate in prospective randomised studies. Elective lymph node dissection is associated with significant morbidity which includes lymphedema, wound complications and paresthesias of the extremity. For this reason we use an alternative operative approach uses selective lymphadenectomy with identification of the sentinel node.

Dermatologic Surgical Procedures↗

PubMed1997

Experience acquired by applying gentamicin-sponge.

Chronic suppuration is a reverting problem in surgical practice. The concerned region either has insufficient circulation due to basic disease, or systemic antibiotics takes no effect due to inflammatory barrier developed meanwhile. For this reason Authors initiated systematic use of gentamicin sponge (Garamycin, Schering-Plough, USA) two years ago. During this period we implanted gentamicin sponge in 40 cases. After primary intervention in 85% of treated patients we observed complete recovery, or in case of ulcus cruris we reached proper condition for skin-transplantation. Three patients needed further incision and in two cases amputation of diabetic foot could not be avoided. Our results support the effectivity of gentamicin sponge in treating local inflammatory processes supplementing and increasing efficiency of surgical procedures.

Amputation, Surgical↗

PubMed1997

Experiences with duodenum preserving pancreatectomy.

According to the principle of surgery for chronic pancreatitis the preservation of pylorus, duodenum or distal part of common bile duct gives the benefit of more physiological intervention. 2 patients with duodenum preserving pancreatectomy are presented. The operation was carried out for chronic pancreatitis. Both patients had jaundice and needed T drainage. Both patients suffered from very severe malnutrition with cachectic condition adding severe pain. None of them proved to be malignant by the frozen section. Previous diabetes, severe chronic inflammation of the whole pancreas, destruction of the pancreatic ductal system and cysts helped the decision-making for ablation of pancreas with preservation of duodenum which seems organ saving procedure. In comparison with the Whipple operation the duodenum-preserving pancreatectomy spares the patient a gastrectomy, a duodenectomy and a resection of distal common bile duct.

Cachexia↗

PubMed1997

Resection of giant schwannoma by combined surgical exposure.

Contrary to the past experience the giant Schwannoma with symptoms of canalis vertebralis compression has been removed by combined surgical exposure in one sitting. Laminectomy, decompression of the canalis vertebralis and immediately subsequent extracanalicular resection of the tumour by retroperitoneal approach was performed in one sitting by two surgical teams. The advantages of the combined surgical exposure: 1. The affliction of the patients caused by the operation significantly decreased. 2. The expenses of the treatment, nursing and hotel decreased as well. 3. The surgical team of different specialists remove the tumour together in both approaches.

Aged↗

PubMed1997

Diagnostic-staging laparoscopy.

Recently instead of the old fashioned, traditional explorative laparotomy the newer up-to-date procedure, the diagnostic-staging laparoscopy has been generally used in the everyday surgical practice of the Authors. Evaluating 32 diagnostic and staging laparoscopy Authors draw the attention to the importance of this procedure which has high diagnostic value, and reduces the complication rate. Biopsy, cytology, frozen section can be done. Authors carries out diagnostic and staging laparoscopy in cases of esophageal, liver, stomach and pancreas tumours just immediately before surgery.

Abdomen↗

PubMed1997

Experiences with ethanol infiltration of the liver metastases of colorectal tumors (preliminary study).

With the aid of improvement in imaging technique and with the ability of detection of hepatic tumours, the successful treatment of primary and secondary hepatic tumours using surgical methods has gained importance. Metastasectomies were performed in 16 cases at our department in 1996. In 6 cases atypical resections and/or infiltration with 96% ethanol were performed. In 3 instances ethanol infiltration into the metastases were accomplished during the resection, in 4 cases--when metastases were discovered 1-4 year after the resection of the primary tumours--the same method was used during the relaparatomy. 96% ethanol was injected directly into the metastatic tumours during operations. The early ultrasonograph examinations proved the total destruction of the metastases in diameter of 1-3 cm, and partial necrosis of the large (d = 3-8 cm) tumours. Two patients were lost from the follow up. Five patients are still alive after 2-8 months of the ethanol infiltration. In one patient after the ethanol infiltration of metastases /d = 3-5 cm/ in 6 segments of the liver we observed the dissemination of the tumour.

Aged↗

PubMed1993

Prolongation of the QTc-interval reflects the severity of autonomic neuropathy in primary biliary cirrhosis and in other non-alcoholic liver diseases.

It was the aim of our study to prove a potential correlation (a) between laboratory findings of cholestasis and autonomic neuropathy (AN) and (b) between the severity of AN and the prolongation of the corrected QT-time (QTc). The five standard tests of autonomic cardiac neuropathy were investigated. QTc was calculated according to Bazett's formula. 12 out of 14 patients with primary biliary cirrhosis, 18 out of 21 patients with HBsAg positive liver diseases and 11 out of 14 patients with cirrhosis of other origin had AN. No significant correlation between the laboratory parameters of cholestasis and AN was found. Abnormal QTc values (> 440 m/sec) were observed significantly more often (p < 0.002) in patients with AN than in patients without AN. Significant linear regression (p < 0.01) could be confirmed between the prolongation of the QTc-time and the severity of AN. Besides the non-invasive investigation of the cardiovascular reflexes the evaluation of the QT-time might be an additional diagnostic means to identify patients with an increased cardiovascular risk in chronic non-alcoholic liver diseases.

Adult↗

PubMed1990

[Autonomic neuropathy in chronic liver diseases].

Autonomic neuropathy has been evaluated by various cardiovascular bedside tests in 99 patients with chronic alcoholism (33 alcoholics without liver disease, 33 patients with fatty liver and 33 with cirrhosis), in 10 patients with primary biliary cirrhosis, in 12 patients with cirrhosis of other origin, and in 40 healthy controls. Parasympathetic integrity was evaluated by beat-to-beat variation during deep breathing (6 min), Valsalva manouver and standing up, sympathetic function by blood pressure response to standing up and to sustained handgrip test. Autonomic reflex damage was found in all groups examined. Patients with alcoholic cirrhosis exhibited the most severe alterations. Our results suggest, that chronic hepatopathy itself presents a pathogenetic factor of autonomic neuropathy. Autonomic failure has to be considered as a possible cause of symptoms in liver diseases with all its prognostic consequences.

Adult↗