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Biomedical subjects

M Barta

Publications and source records attributed to M Barta.

At least 19 recordsLinked to original sources
PubMed1999

Comparative investigation on the effect of T-2 mycotoxin on lipid peroxidation and antioxidant status in different poultry species.

The effect of low dose T-2 toxin was investigated in chicken, duck and goose. The purpose of the present study was to investigate the effect of T-2 toxin on the lipid peroxidation and on the activity of glutathione redox system (amount of reduced and oxidised glutathione and the activity of glutathione peroxidase) in blood and liver. The treatment lasted days and two samples were taken, first at the time of lowest feed intake and second when the intake was the same as the control. It was found, that lipid per oxidation as detected by the amount of malondialdehyde increased in all of the species and tissues but the changes varied by species. The most sensitive species was goose followed by duck and chicken, and the most sensitive tissue was the liver followed by blood plasma and red blood cells.

Animals↗
PubMed1996

[CT-guided interventions in diseases of the small pelvis following rectal resection].

60% of relapses of rectal cancer after abdominoperineal resection occurs at the site of the surgical intervention. Early detection of these recurrent tumours is vital. Among the up-to-date imaging systems CT is the most sensitive method in diagnosis of pelvic tumours. Despite the accurate imaging diagnosis the nature of lesions remains sometimes ambiguous. 11 CT guided biopsies and 2 punctures were performed because of suspected local recurrence or abscess. As a result of biopsies, local recurrence was histologically proven in 6 cases, fibrosis in 4, inflammatory disease in 1. Both punctures revealed the cytological diagnosis of abscess. There were no complications. The interventions were carried out in prone position through the greater sciatic foramen. In the knowledge of the exact anatomy of this region, the procedure can be performed safely by CT guidance and a correct diagnosis can be achieved.

Abscess↗
PubMed1996

Effect of lipid peroxide loading on lipid peroxidation and on the glutathione and cytochrome systems in rabbits.

New Zealand White rabbits (6 males and 6 females) were fed a diet of high lipid peroxide content (peroxide value: 249.05 meq/kg fat) for 21 days. Twelve rabbits served as controls (peroxide value: 40.3 meq/kg fat). The lipid peroxide loading did not cause clinical signs. The rate of lipid peroxidation, as measured on the basis of thiobarbituric acid reactive substances (TBARS), was significantly (P < 0.05) higher in all of the investigated tissues, in the following order: liver > red blood cells (RBC) > blood plasma. Reduced and oxidised glutathione content was higher in the blood plasma (P < 0.01) and liver (P < 0.001) of rabbits exposed to the peroxide load. Lipid peroxide loading decreased the activity of glutathione peroxidase in the blood plasma, RBC haemolysate and liver and that of glutathione reductase in the liver. The amount of cytochrome P450 (both CO- and metyrapone-reduced) and the activity of cytochrome c (P450) oxidoreductase in the microsomal fraction of the liver homogenate were also lower in the group exposed to lipid peroxide load. Subchronic alimentary lipid peroxide loading in the presence of sufficiently high levels of antioxidants in the complete feed was found to increase the rate of lipid peroxidation and markedly lower the activities of both the glutathione and xenobiotic transforming enzyme systems without causing any clinical signs of toxicity.

Animals↗
PubMed1991

[Detection of estrus and determination of the optimal time for insemination in polar foxes (Alopex lagopus)].

Oestrus cycles were investigated in seven polar foxes: the investigation consisted of evaluation of clinical symptoms of heat (vulva enlargement), measurement of vaginal mucus electrical resistance and determination of progesterone concentrations in the blood plasma of foxes; the objective was to determine optimum insemination time. The females were inseminated with fresh semen intravaginally by means of a pseudopenis, a day following the record of maximum electrical resistance of vaginal mucus and at the minimum progesterone concentration in blood plasma of 30 ng.ml-1. The females were reinseminated on the following day. The insemination dose had a volume of 1 ml with sperm concentrations of 150.10(6). Clinical symptoms of heat were observed in six out of the seven test foxes. Heat detection by means of measuring vaginal mucus electrical resistance was successful also in six females. Progesterone test enabled to detect heat in five females. Out of six inseminated females, five foxes became pregnant (83.3%) and a total of 33 cubs were born; this is 5.5 cubs per female.

Animals↗
PubMed1990

[Management of intussusception in infancy by hydrostatic desinvagination under ultrasonic monitoring].

The ultrasonographic diagnosis of intussusception may be a recent complementation of X-ray fluoroscopy controlled hydrostatic desinvagination. Ultrasound is also useful in follow-up of the effectiveness of conservative management. By presenting their experience gathered by successful treatment of one case, the authors' aim is to contribute to the spread of this method.

Catheterization↗
PubMed1989

Hyperthermic modulation of respiratory inhibition factor- and iron releasing factor-dependent macrophage murine tumor cytotoxicity.

Hyperthermia modulated the cytotoxic activities of murine macrophages cocultured with EMT-6 tumor cells, altered the production of the monokines RIF (respiratory inhibition factor) and FeRF (iron-releasing factor) by these effector cells, and perturbed the activities of these monokines against EMT-6 cells. Cytotoxic activities of heated murine macrophages activated by Bacillus Calmette-Guérin were inhibited by heat doses of 40.5 degrees C for greater than or equal to 1 h if heating preceded triggering by the endotoxin lipopolysaccharide; however, cytotoxic activities were better retained if triggering preceded heating by 2 h. Treatment-sequence dependencies were also found in the secretion of some monokines that participate in these macrophage cytotoxic effects. Secretion of both RIF and FeRF by macrophages was slightly augmented or at least better retained if triggering of macrophages occurred several hours before heating for 1 h at 40.5-43 degrees C or for 24 h at 39-40.5 degrees C. If heating was nearly simultaneous with triggering or preceded it by several hours, there was a dose-dependent decrease in monokine secretion. The sensitivity of tumor cell targets to these monokines was also modified by the treatment sequence. When EMT-6 cells were treated with RIF- or FeRF-containing macrophage conditioned supernatants 1 h before heating at 40.5-43 degrees C, the RIF-treated cells became sensitized and the FeRF-treated cells retained better cytotoxic response than if cells had been treated 1 h after heating. Chronic heating for 24 h at 39-40.5 degrees C showed less dependence of tumor cell response on treatment sequence. Similar observations have recently been made in our laboratory for the interaction of tumor necrosis factor cytotoxic pathways with hyperthermia (Klostergaard et al., J. Biol. Response Modif., in press, 1989; Tomasovic et al., Int. J. Hyperthermia, in press, 1989). Those results and the present observations with the monokines RIF and FeRF support our hypothesis that the cytotoxic actions of macrophages and the cytotoxicity of endogenously added monokines can be augmented by appropriately constructed sequences combining hyperthermia with either macrophage priming/triggering or monokine treatment of tumor cells.

Adenocarcinoma↗
PubMed1989

[Ultrasonic examination of the brain (through an opening in the skull)].

Post-operative neurosonography - through calvarial defect. 9 patients were examined by post-operative high resolution real-time ultrasound, using an operative calvarial defect. The findings of 2 patients are analysed in details. The authors have found good agreement with computed tomography, with other imaging methods and pathology as well. They suggest sonographic examination as a first step in the follow-up control of the pathological processes in patients with burr holes.

Adult↗
PubMed1989

[Ultrasonic detection of a tumor of the posterior cranial fossa in an infant].

The sonographic diagnosis and surgical treatment of the ependymoblastoma of a 9,5-month old infant is reported. The tumor originated from the posterior scale and caused obstruction in the aquaeductus cerebri and hydrocephalus. The modern radiological diagnosis of tumors in the posterior scale is reviewed.

Brain Neoplasms↗
PubMed1989

[Collection of sperm from foxes using electroejaculation under halothane anesthesia].

A method has been developed for the collection of ejaculate from anaesthesized dog foxes. General anaesthesia was produced by inhaling 3 to 5% narcotan mixed with oxygen, the inhalation rate being two litres per minute. An electroejaculator with a bipolar electrode, introduced in the rectum, was used for the electrostimulation of ejaculation. The voltage needed to produce the ejaculation effect and the number of impulses depended on the individuality of the foxes. The average amount of ejaculate per one collection was 0.86 ml, the sperm motility percentage was 74.80% sperm concentration was 270.62 x 10(3) spermatozoa per mm3, and the average pH value was 6.87.

Anesthesia, Inhalation↗
PubMed1989

Hyperthermic modulation of tumor necrosis factor-dependent monocyte/macrophage tumor cytotoxicity in vitro.

Tumor necrosis factor (TNF) production by human peripheral blood monocytes and murine bacillus Calmette-Guerin-activated peritoneal macrophages was strongly influenced by acute hyperthermia. If hyperthermia was administered simultaneously with or preceding lipopolysaccharide triggering, production was severely ablated by 42 degrees and 43 degrees C treatments; however, if triggering preceded heating by at least 90 min, production was either unaffected or markedly enhanced. A somewhat similar pattern was reflected with chronic heating. TNF production by murine macrophages was inhibited with 39 degrees C heating and completely blocked by 40.5 degrees C treatment, if triggering coincided with the initiation of hyperthermia. However, augmentation of production occurred with either of these temperatures if triggering preceded hyperthermia by as little as 90 min. Human monocytes demonstrated greater resistance to the deleterious effects of coincident triggering and heating with respect to TNF secretion than the rodent effectors, but the response was otherwise very similar. The TNF-sensitive phenotype of the L929 cell could be augmented by chronic or acute hyperthermia, markedly so with a 43 degrees C treatment. The TNF-resistant phenotype of the EMT-6 cell could be reversed by chronic heating at 40.5 degrees C, or by acute heating at 43 degrees C, but only if the latter followed TNF treatment. These results reflect important regulatory controls of TNF production and responses in tumor cells which are susceptible to hyperthermia manipulation.

Animals↗
PubMed1989

[Fertilizing capacity of the ejaculate of nutria (Myocastor coypus) after the removal of the seminal vesicles as evaluated by the penetration test and natural mating].

The fertility of male coypu sperm following seminal vesicle extirpation was investigated using the penetration test into the egg of Syrian golden hamster (Mesocricetus auratus). Ejaculates were obtained from five males by means of electro-ejaculation under halothane narcosis. The results of the zona-free hamster eggs (ZFHE) penetration test showed that the ejaculates of all the surgically treated coypu males were fertile and that ZFHE value fluctuated from 54 to 76.6%. The results obtained in experiments with natural mating revealed that the extirpation of male coypu seminal vesicles did not affect their fertility. In total 47 foetuses were found post mortem in ten coypu females covered by surgically treated males, which on average represented 4.7 foetuses per female.

Animals↗
PubMed1989

[Fluctuations in the level of progesterone in the peripheral blood of nutria during pregnancy].

The fluctuations in the concentrations of progesterone in peripheral blood of three intact coypus and three coypus after natural mating were investigated for the period of four months. Immediately after mating the concentrations of progesterone are low (1.5-2.4 ng.ml-1), the maximum values reach the peak between the 14th and 15th week of gravidity (12.50-20.72 ng.ml-1), whilst there is almost no change in the intact females. On the last days of gravidity the values of progesterone decrease rapidly and they are very low on the day of parturition (1.0-2.5 ng.ml-1). The concentration of progesterone in the blood plasma of intact females in the test period is low (0.09-3.18 ng.ml-1).

Animals↗
PubMed1989

Neutral red uptake and clonogenic survival assays of the hyperthermic sensitization of tumor cells to tumor necrosis factor.

Vital dye uptake and postfixation dye assays have recently been used to examine the interaction between short-term (24-48 h) exposures to the monokine, tumor necrosis factor (TNF), and hyperthermic treatments with the finding that synergistic increases in cytotoxicity occurred. However, survival measured by these short-term dye assays is not necessarily closely related to eventual loss of clonogenic capacity. Treatment-induced growth delays, delayed cytotoxic effects, or perturbations of vital dye sequestration mechanisms could result in a different measurement of surviving fraction than given by a clonogenic assay. In this study we directly compared the neutral red vital dye uptake and clonogenic survival assays and confirmed in both assays that TNF-sensitive (L-929) and TNF-resistant (EMT-6) phenotypes show greatly reduced survival when treated with combined recombinant human TNF (1.0-0.0005 micrograms/ml) and hyperthermia (1-2 h at 43 degrees C). Moreover, we confirmed that sensitization of the TNF-resistant EMT-6 cells was largely dependent on monokine treatment before hyperthermia and was reduced by the reverse sequence. The greatest sensitization of TNF-responsive L-929 cells also occurred when TNF treatment preceded heating. These results for clonogenic survival are consistent with the hypothesis that hyperthermia used in combination with TNF in vivo is more cytotoxic than TNF or hyperthermia separately.

Animals↗
PubMed1986

Progesterone secretion by induced corpora lutea (CL) of anestrous bitches after administration of gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (HOG).

Sixteen bitches were treated with pregnant mare serum gonadotropin (PMSG; 44 IU/kg bwt) intramuscularly (i.m.) for nine consecutive days and each was given 500 IU HOG i.m. on the tenth day or on the first day of induced estrus (Day 0). On Day 12, each bitch was randomly assigned to three groups and treated as follows: Group 1-six bitches, each given 10 mcg GnRH i.m.once every 24 hr; Group 2-six bitches, each given 500 IU HOG i.m. once every 24 hr; and Group 3-four bitches, each given 5 ml 0.9% saline i.m. once every 24 hr. Treatments were continued until Day 55. Blood samples were obtained prior to treatment and every other day until Day 55. Plasma progesterone concentrations were determined by radioimmunoassay (RIA) and data arranged using a split-plot design, with treatment as the main plot and days of sampling as subplots. Analysis of data was by Duncan's Multiple Range Test and treatment-by-day interaction determined by the least-squares method. After treatment, progesterone concentrations from Group 2 were higher (P<0.05) than those of the other groups. A significant effect was seen on Day 20 (P<0.01), while on Day 50 the difference approached significance. These findings suggest that HOG is capable of stimulating the production of progesterone by induced CL in the bitch. However, neither HOG nor GnRH prevented premature regression of these induced CL. Results of this study suggest that premature luteolysis of induced CL is probably not due to lack of gonadotrophic support from either the hypothalamus or the anterior pituitary gland.

Journal Article↗
PubMed1984

Clinical and laboratory characterization of Basenjis with immunoproliferative small intestinal disease.

Eleven adult Basenji dogs with immunoproliferative small intestinal disease (IPSID) were studied. Two items of history related to the digestive tract were characteristic: (i) chronic intractable diarrhea in most dogs, and (ii) progressive emaciation. Anorexia was intermittent in only a few dogs. In addition, skin lesions of various degrees of severity were observed, including alopecia of pinnae and ventrum, hyperpigmentation and hyperkeratosis of pinnae, and necrosis and ulcerations of margins of pinnae. The cause of the skin lesions was not determined; however, hypothyroidism did not appear to contribute to the skin changes. Standard hematologic and serum chemical values were not consistently abnormal. However, a poorly regenerative anemia, mild neutrophilia, and increased aspartate aminotransferase and alanine aminotransferase activities were generally observed in severely affected dogs. The Pelger-Huet anomaly was identified in dog 3. Maldigestion and malabsorption as determined by the N-benzoyl-L-tyrosyl-p-aminobenzoic acid and d-xylose test was documented to varying degrees in dogs with IPSID. Maldigestion was correlated with functional pancreatic exocrine insufficiency. Severe malabsorption was documented in only 3 dogs. Serum gastrin values were evaluated in these dogs because of a prior observation of parietal cell hyperplasia and gastric ulceration. Hypergastrinemia was documented in 3 dogs. Additional studies will be necessary to determine whether an acid hypersecretory state contributes to the pathogenesis of IPSID in Basenjis.

4-Aminobenzoic Acid↗
PubMed1982

Luteal function of induced corpora lutea in the bitch.

Nineteen anestrous bitches with a mean of 22 kg body weight and ranging from 2 to 4 years of age were induced to exhibit estrus and ovulate using PMSG and HCG. Twelve days after the first day of estrus, bitches were assigned to four treatment groups. Group (A) consisted of six bitches, Group (B) of five bitches and Groups (C) and (D) of four bitches each. At this time, bitches in Groups (A), (B) and (C) were laparotomized and those assigned to Groups (A) and (B) were bilaterally hysterectomized leaving the cervix and oviducts intact. Although bitches in Group (C) were laparotomized, they were not hysterectomized. Group (D) bitches were not subjected to any surgical procedures. Homologous uterine extract was prepared from each bitch in Group (A) and administered intramuscularly beginning on day 25 (day 0=first day of estrus) and continued every other day for 61 days post-estrus. Bitches in Group (B) were similarly injected with equal volumes of 0.9% saline. Blood samples, obtained prior to laparotomy and every other day for 85 days thereafter, were assayed for plasma progesterone concentrations using radioimmunoassay. One bitch in each of Groups (A) and (D) did not form luteal tissue following treatment with PMSG and HCG although both bitches exhibited estrus following treatment. All other bitches showed an increase in progesterone levels (4 to 19 ng/ml) between the first day of estrus and 10 days post-estrus. Thereafter, progesterone levels progressively declined in all groups with levels below 1 ng/ml between 38 to 40 days post-estrus. Results of this study suggested that CL formed in the bitch following PMSG and HCG treatment have a reduced function compared to non-induced CL of a normal, non-fertile estrous cycle. Such premature CL regression appears to be independent of the presence or absence of the uterus.

Journal Article↗