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Biomedical subjects

M Valent

Publications and source records attributed to M Valent.

At least 19 recordsLinked to original sources

A sewage disposal failure as a cause of ascariasis and giardiasis epidemic in a family.

In monitoring the incidence of intestinal parasites in children and employees of a nursery the authors examined 31 children with 8 (25.81%) and 16 employees with 3 (18.75%) positive results. The authors wanted to examine also the family members of 8 positive children and 3 positive employees but except from the cleaner's family, (Ascaris lumburicoides, Enterobius vermicularis and Entamoeba coli) nobody accepted the offer. All 8 members of a large family except for Patient 1 (a cleaner) and her grandson were without clinical and laboratory findings. They constitute 3 independent families who lived in 1st category flats. On August 31 there was an extensive sewage disposal failure in the ground floor flat of Family II and the flat was flooded by sewage. All family members worked solidarily on cleaning and also the members of Family IV who are friends of Family II. As shown by clinical symptoms of 'virosis', during the pre-patent period and after an outbreak within 73-78 days, laboratory findings of the family members demonstrated a severe family infection equal to a epidemic of intestinal parasitosis. Ascaris lumbricoides was diagnosed in 8 family members (61.54%) and Giardia intestinalis in 7 family members (53.85%) involved in cleaning. Enterobius vermicularis was found in 2 and Etamoeba coli in 1 family member. In monitored persons, in extreme hygienic conditions during the failure and later, a mass contraction arose on the basis of infection. The fact, that family epidemic arose subsequently, proved, in contrast to sporadic findings in children and adults, a 6.4 and 3.3 times higher incidence of Ascaris lumbricoides and a 5.6 and 8.6 times higher incidence of Giardia intestinalis. The authors discus the reasons of incidence and also preventive measures in population. (Tab. 3, Ref. 29.).

Adult↗

Enterobius gregorii--reality or fiction?

Authors present findings based on the actual epidemiologic situation of incidence of E. vermicularis (Linnaeus, 1758) which is till now the uniquely diagnosed parasite of Enterobius species in human population in Slovak Republic. They compared methods used in our laboratories for detection of propagation stages of E. vermicularis ova with methods used in other laboratories, which detect various propagation stages directly in stool. The authors found differences in detection and identification of adult female and male parasites. The relevance of sings for Enterobius gregorii (Hugot, 1983) diagnosis was assessed from the point of view of ontogenetic and morphologic development of E. vermicularis. Authors describe the isolation of a gravid female of Enterobius species from the patient, which showed some somato-morphological signs different from that found in E. vermicularis females. Possible explanations of such deviations are being discussed. The study is illustrated by pictures showing morphological differences in females. (Fig. 3, Ref. 28)

Animals↗

Oestradiol microimplants in the ventromedial preoptic area inhibit secretion of luteinizing hormone via dopamine neurones in anoestrous ewes.

Oestradiol exerts a season-specific negative feedback effect on the GnRH/LH neurosecretory system of the Suffolk ewe. This neuroendocrine suppression is mediated in part by dopamine A15 neurones, but these neurones do not possess the oestrogen receptor. Based on indirect evidence, we hypothesized that oestrogen receptor-containing neurones in the ventromedial preoptic area (vmPOA) may be the initial step in a neuronal system whereby oestradiol suppresses GnRH secretion during the non-breeding season. To test this, three experiments were conducted using ovariectomized ewes receiving either empty or oestradiol-containing bilateral microimplants directed at the vmPOA or s.c. subcutaneous oestradiol-containing implants. In the first experiment, LH pulse frequency was measured on days 0, 1, 7 and 14 of treatment during seasonal anoestrus. In vmPOA oestradiol and s.c. oestradiol groups only, LH pulse frequency was suppressed on days 7 and 14, with maximal suppression evident by day 7. In the second experiment, this protocol was repeated during the breeding season, with LH pulses examined on days 0 and 7; LH pulse frequency did not change in any group. The third experiment tested if the effect of vmPOA oestradiol during anoestrus could be overcome by an injection of the dopamine-D2 receptor antagonist (-)-sulpiride. The vmPOA microimplants and s.c. oestradiol implants again suppressed LH pulse frequency and this was reversed by sulpiride in vmPOA oestradiol ewes. We conclude that oestradiol acts on cells in the vmPOA to stimulate a system involving dopamine neurones that inhibits GnRH/LH pulsatility in the anoestrous ewe.

Anestrus↗

The effect of photoperiod and food intake on daily changes in plasma calcitonin in broiler breeder hens.

The roles of photoperiod, energy balance, and concentrations of plasma total calcium (CaT) on daily changes in plasma calcitonin (CT) were investigated in broiler breeder hens (84-100 weeks old). In the first study, broiler breeder hens (n = 24), reared on 14L:10D, were divided into two groups. One group was transferred from a restricted diet (DR) of 150 g/day to ad libitum (AL) for 14 days, while the other group remained on DR. After 2 weeks of ad libitum feeding, birds from each group (AL and DR) were bled every 2 hr for 24 hr for measurement of plasma CaT and CT. In a second study, the hens (n = 20) were transferred to continuous light (LL) for 30 days. After the 30 days, food was removed from one group for 48 hr prior to blood sampling for 24 hr at 3-hr intervals. In a third study, birds were transferred to an ahemeral light cycle (11L:10D) for 28 days. Food was removed from the birds (n = 11) for 48 hr prior to blood sampling every 3 hr for 24 hr. Four weeks later the same birds were bled again for 24 hr, but this time the birds were maintained on a restricted feeding schedule. Plasma CT was measured by a specific heterologous electrochemiluminescent (ECL) assay while plasma CaT was measured by atomic absorption. The results showed that plasma CT concentrations did not correlate with plasma CaT concentrations. Comparisons made between initial and final CaT and CT concentrations indicated an effect of stress due to repeated handling of the birds. Concentrations of plasma CT were significantly reduced in the fasted animals (P < 0.05) compared to diet-restricted controls. There was a significant increase in plasma CT during the dark period of fed animals which was abolished in animals maintained on LL or fasted. In conclusion, a surge in plasma CT requires that the hens be provided food and that they be exposed to a dark cycle.

Animals↗

Evaluation of selected parameters of a metabolic profile and levels of cadmium in reproductive organs of rabbits after an experimental administration.

Selected serum parameters of metabolic profile and distribution of cadmium in reproductive organs in rabbits were studied after an acute and subchronic administration. After an i.p. application of cadmium (1.5 mg.kg-1) a significant increase of glucose (5.90 mmol.l-1) and cholesterol (2.22 mmol.l-1) was observed. There were no significant differences in these parameters after the subchronic (5 month) p.o. application. The concentration of AST and ALT significantly decreased after a subchronic p.o. administration (1.0 mg.kg-1) but not after an acute i.p. application. There were no significant differences in the level of total proteins and total lipids. The highest accumulation in reproductive organs (testis, ovary, uterus) was observed after i.p. administration. The level in the testis was 40 times higher than in the control group (0.04 mg.kg-1; 1.93 mg.kg-1), 174 times higher in the ovary (0.03; 5.21) and 65 times higher in the uterus (0.04; 2.59). After a subchronic p.o. application, the concentration was only 2.5 times higher in the testis (0.04; 0.10), 16 times higher in the ovary and 6 times higher in the uterus than in the control group.

Alanine Transaminase↗

[Helminth and protozoan findings in the water of school swimming pools].

In the year 1993 repeated parasitological examinations of water and the equipment of an indoor school swimming pool were made. The sanitary and hygienic regime of the swimming pool was not respected and parasitological findings corresponded to this fact. Examinations of the swimming pool revealed the presence of helminths--Ascaris lumbricoides, Enterobius vermicularis and Taenia saginata, as well as of protozoa--Giardia intestinalis and Entamoeba coli. The parasites were detected in samples taken under operation conditions from free water, from walls of the swimming pool an from its equipment, as well as from the sediment in sand filters. The authors pointed out that increased occurrence of parasites was connected with exceeding of swimming pool capacity. They noted also massive occurrence of non-pathogenic protozoa in water and sediment of the swimming pool, which was considered an indicator of increased pollution. They drew attention to the possibility of infection with intestinal parasites present in the swimming pool water. The conditions are discussed which enable parasites to reach the stage in which they are can infect bathing people and cause parasitoses in them. The authors suggested which places of a swimming pool should be examined in the course of parasitological investigations. They took steps to prevent contamination of swimming pool water with developmental stages of parasites and to prevent their maturation.

Animals↗

Evaluation of acid-base disorders in dairy cows using principal component analysis and empiric equations.

Acid-base disorders were studied in two groups of dairy cows. According to conventional interpretation in the 1st group of dairy cows (n = 10) the results of the acid-base parameters indicated respiratory alkalosis and in the 2nd group (n = 10) metabolic acidosis. The data of the two groups were examined using principal component analysis. So called "reduced variables"--principal components for each animal were calculated. Each experimental animal was projected in the coordinates of 3 principal components K1, K2 and K3. The components K1, K2 and K3 comprised a 90% data variability. The importance of variables for a dividing of groups (1 and 2) was quantified. The most important were pCO2, (HCO3)' and BE. It was proved according to mathematico-empiric equations that dairy cows of 1st group suffered from acute respiratory alkalosis. In the 2nd group of dairy cows the combined acid-base disorder was confirmed using the equations for metabolic acidosis and chronic respiratory acidosis. The use of PCA method and empiric equations for acid-base imbalances shows the possibilities for gaining new knowledge how to make the diagnostic process more exact.

Acid-Base Imbalance↗

Proteinases of Trichomonas vaginalis: antibody response in patients with urogenital trichomoniasis.

Immunoprecipitation combined with electrophoresis in gelatin-polyacrylamide gels was successfully used for detection of antibodies against numerous proteinases of Trichomonas vaginalis in infected patients. The method proved to be highly specific as anti-proteinase antibodies were absent in women with negative cultivation of T. vaginalis and no history of trichomoniasis. Sera of 71% and vaginal washes of 86% patients with trichomoniasis were positive for these antibodies. In vaginal washes, but not in sera, antibodies were partly complexed with proteinases, possibly of trichomonad origin. It was also shown that serum antibodies as well as local anti-proteinase antibodies persisted for weeks after patients had been cured.

Adult↗

Vaginal leukocyte characteristics in urogenital trichomoniasis.

Morphological and functional characteristics of vaginal exudate leukocytes were examined in 47 patients with urogenital trichomoniasis. Electron microscopic morphology, viability, phagocytosis of Candida albicans blastospores and ability to undergo respiratory burst in the iodonitrotetrazolium reductase test were evaluated in these cells. Vaginal inflammatory leukocytes were almost exclusively polymorphonuclear neutrophils, and their concentration was positively correlated (r = 0.58; p less than 0.001) with the number of trichomonads in the exudate. Median leukocyte viability reached 39% and both phagocytic and tetrazolium reductase activities of these cells were significantly reduced in comparison with those of circulating polymorphonuclear leukocytes. Patients with a clinical picture of severe mucosal inflammation had significantly higher vaginal exudate leukocyte concentrations and viability than those without inflammatory signs. The possible role of vaginal leukocytes in the pathogenesis of urogenital trichomoniasis is discussed.

Adolescent↗

[Super Duo latex fixation test--an alternative diagnostic method for trichomoniasis?].

The reliability of the new latex-agglutination test super duo for the detection of antigens of T.vaginalis and Candida, a prospective screening method for trichomoniasis, was verified. In a group of 27 women the microscopic and culture diagnosis of trichomoniasis was established in 22 patients and 21 of them were positive in the latex-agglutination test for T.vaginalis. The immunochemical examination was not positive in either of the five women with findings of negative cultivation for the parasite. The intensity of agglutination was in good correlation with the clinical signs of inflammation. In asymptomatic women the reaction was indistinct. Vaginal candidiasis was revealed by culture in two women, one of them was positive on the latex-agglutination test for Candida. One woman with negative cultivation finding for yeast microorganisms was positive in the immunochemical test. Examination of asymptomatic sexual partners of trichomoniasis patients would be necessary to evaluate the suitability of the set for T.vaginalis infection screening.

Adolescent↗

Dot-immunobinding assay with monoclonal antibody for detection of Trichomonas vaginalis in clinical specimens.

A rapid and specific dot-enzyme immunoassay (DIBA) using monoclonal antibody was introduced for detection of Trichomonas vaginalis antigen in vaginal and urethral materials. The results of DIBA were compared with culture findings of the parasite in 245 female patients. Taking culture as the reference method, DIBA had a sensitivity of 92% and a specificity of 93%. The predictive value of a positive test was 98% and that of a negative test 77%. The efficacy of wet mount, culture and DIBA were compared in 134 women with trichomonal infection. The most sensitive method was cultivation with a positivity of 99.3%. DIBA was as sensitive as the wet mount (92%). In 51 sexual partners of women with trichomoniasis DIBA proved to be ineffective. The sensitivity of the assay with corpuscular antigen of T vaginalis was 1 x 10(4) cells/ml, with soluble antigen 47 micrograms/ml. Specificity of the assay was confirmed by lack of any cross-reactivity with Trichomonas tenax. Tritrichomonas mobilensis and Candida albicans.

Adolescent↗

[Insulin and thyroxine levels in dairy cows during lactation and after a 9-day fast].

The aim of the study was to observe the effect of longer fasting of dairy cows during lactation on the insulin and thyroxine levels in blood serum. The test was performed at the Research Institute of Animal Production, Nitra. The blood samples for determination of the hormone levels were collected in the morning from the vena jugularis of four fasted 4-5-year-old dairy cows of the Black Pied breed during lactation with an average daily performance of 16.91. The blood was collected on the first, fifth, sixth, seventh, eight and ninth day (fasting) and then on the fifteenth and twenty first day of the test (feeding). The insulin level in the blood serum of fasted dairy cows was more or less balanced till the seventh day of fasting, and ranged from 4.33 to 4.91 microU.ml-1. On the last two days of fasting, the insulin level increased up to 7.11 microU.ml-1 on the 9th day of fasting. The insulin level was significantly higher during feeding than during starvation. The thyroxine level was statistically significantly lower in fasted dairy cows. Increasing insulin level at the last two collections of the fasting period was probably closely connected with the shifting of the endocrine balance from dominant position of insulin to the dominance of the growth hormone and glucocorticoids. A comparatively high effect on the increase of the insulin level was exerted during that time also by the increasing amounts of non-esterifed fatty acids. Starvation significantly reduced the levels of the studied hormones in dairy cows during lactation.

Animals↗

[The first period in the history of the Institute for General Biology].

Of the history of the Institute for General Biology, School of Medicine, Comenius University, the study deals with the first period, namely the years 1923-1945. The institute greatly benefited from the activities of Prof. MUDr. Zdenĕk Frankenberger who established it and was its Head in the first year of its existence. From 1925 till 1943 the institute was directed by Prof. MUDr. Jozef Florian Babor. Professor Babor's main interest was focused on malacology and he achieved international reputation in this field of zoology. He investigated the flora and fauna of Slovakia, was engaged in limnology, and cooperated with Professor Frankenberg in the field of anthropology and primatology. Over these years, prof. Vojtech Nábĕlek and MUDr. Bohumil Krajnik greatly contributed to the activities and development of the institute along with Prof. Babor. The Institute for General Biology was already in the first period of its existence reknown not only for its teaching activities but was also internationally appreciated in the medical, biological and historiographic community.

Academies and Institutes↗

Specific parasitism of purified vaginal epithelial cells by Trichomonas vaginalis.

Human vaginal epithelial cells (VECs) from vaginal swabs obtained from normal women or from patients with trichomoniasis were purified, and VEC parasitism by Trichomonas vaginalis was examined. Trichomonads bound equally well to live or dead VECs, and up to 20% of VECs were parasitized. Trichomonal cytadherence of human VECs was time, temperature, and pH dependent. Saturation binding levels of live trichomonads to VECs gave approximately 2 organisms adherent to parasitized VEC. No differences in cytadherence levels were detected by different isolates to VECs from the same patient compared with adherence to VECs from normal individuals. Trypsinized, live T. vaginalis organisms failed to recognize VECs. A ligand assay identified four adhesin candidates, and only organisms without a prominent immunogen on the surface (negative phenotype) cytadhered to VECs and synthesized the adhesins, confirming the results of a recently published report by us on adherence to HeLa cell monolayers (J. F. Alderete and G. E. Garza, Infect. Immun. 56:28-33, 1988). These data show the ability of T. vaginalis to parasitize human vaginal epithelial cells in a specific receptor-ligand manner.

Animals↗

Fewer Trichomonas vaginalis organisms in vaginas of infected women during menstruation.

The aims of the present study were to count Trichomonas vaginalis organisms recovered from the vaginas of patients with trichomoniasis, and to obtain data concerning changes in sizes of trichomonal populations during the menstrual cycle. In about 80% of symptomatic as well as symptomless patients, more than 1 x 10(5) parasites per ml could be obtained from vaginal washes. During menstruation, however, the number of trichomonads decreased appreciably, with subsequent increases within three to six days after bleeding. The results indicated that sufficient numbers of fresh trichomonads may be obtained from vaginal washes for biochemical and molecular experiments and also confirm the previously reported trichomonocidal effect of menstrual blood complement in vivo.

Adolescent↗

Differential susceptibility of fresh Trichomonas vaginalis isolates to complement in menstrual blood and cervical mucus.

The ability of complement in human menstrual blood and cervical mucus to kill Trichomonas vaginalis was compared with that of complement in serum, and 95 fresh trichomonal isolates obtained from vaginal wash material were evaluated for susceptibility to complement immediately after isolation. Only serum and menstrual blood with haemolytic activity produced total cytolysis of T vaginalis. The cytolytic abilities of these fluids were totally inactivated by treatment with heat or edetic acid (EDTA), which confirms the role of complement in cytolysis. Most cervical mucus samples had no detectable trichomonal cytotoxic properties. The cytotoxic activity in the remaining samples was not due to complement, as it was heat stable. Fresh isolates of T vaginalis and subpopulations of fresh isolates differed in their susceptibility or resistance to complement mediated lysis in serum. Resistance to complement did not remain stable after trichomonads were grown in vitro.

Adolescent↗