Leptin inhibits cortisol and corticosterone secretion in pathologic human adrenocortical cells

Regulation of adrenal corticosteroid secretion by leptin may involve interactions at multiple levels of the hypothalamic-pituitary-adrenal axis. To investigate the possible direct effects of leptin on corticosteroid secretion of human adrenocortical adenomas, cells from adrenocortical adenomas causing primary aldosteronism (n = 1) and Cushing's syndrome (n = 1), as well as cells from nonhyperfunctioning adrenocortical adenomas (n = 5) were isolated and incubated for 2 h with human recombinant leptin (1-1000 ng/ml) in the presence and absence of adrenocorticotrop hormone (ACTH), then cortisol, corticosterone and aldosterone concentrations in incubating media were determined using radioimmunoassays. It was found that leptin effectively and dose-dependently inhibited basal and ACTH-stimulated cortisol and corticosterone secretion in the three types of human adrenocortical adenoma cells. The inhibiting effect of basal corticosterone secretion was detectable in the presence of leptin concentration as low as 1 ng/ml, with decreases of corticosterone secretion to 34+/-4%, 57+/-11% and 79+/-9% in Cushing's syndrome, primary aldosteronism, and nonhyperfunctioning adrenocortical adenoma cells, respectively. The inhibition of basal cortisol secretion in the presence of low concentration of leptin was less prominent, but 10 ng/ml leptin significantly diminished basal cortisol secretion to 81+/-9% in adrenocortical adenoma cells from Cushing's syndrome, to 68+/-6% in adenoma cells from primary aldosteronism, and to 83+/-8% in cells from nonhyperfunctioning adenomas. The inhibition of ACTH-stimulated cortisol and corticosterone secretion by leptin was similar to those found in cells without ACTH stimulation. By contrast, leptin even at 1000 ng/ml concentration exerted no clear effect on basal and ACTH-stimulated aldosterone secretion in cells from primary aldosteronism and in those nonhyperfunctioning adenoma cells in which aldosterone secretion was detectable. These results indicate that leptin is a potent inhibitor of cortisol and corticosterone secretion in human adenomatous adrenocortical cells. The inhibition of these corticosteroids by leptin may represent a potentially important interaction that exists between leptin and the hypothalamic-pituitary-adrenal axis.

Morphologic, host specificity, and genetic characterization of a European Cryptosporidium andersoni isolate

This study was undertaken in order to characterize a Cryptosporidium muris-like parasite isolated from cattle in Hungary and to compare this strain with other Cryptosporidium species. To date, the large-type oocysts isolated from cattle were considered as C. muris described from several mammals. The size, form, and structure of the oocysts of the Hungarian strain were identical with those described by others from cattle. An apparent difference between the morphometric data of C. muris-like parasites isolated from cattle or other mammals was noted, which is similar in magnitude to the differences between Cryptosporidium meleagridis and Cryptosporidium felis or between Cryptosporidium serpentis and Cryptosporidium baileyi. The cross-transmission experiments confirmed the findings of others, as C. muris-like oocysts isolated from cattle fail to infect other mammals. The sequence of the variable region of small subunit (SSU) rRNA gene of the strain was 100% identical with that of the U.S. Cryptosporidium andersoni and C. andersoni-like isolates from cattle. The difference between the SSU rRNA sequence of bovine strains and C. muris is similar in magnitude to the differences between C. meleagridis and Cryptosporidium parvum anthroponotic genotype or between Cryptosporidium wrairi and C. parvum zoonotic genotype. Our findings confirm that the Cryptosporidium species responsible for abomasal cryptosporidiosis and economic losses in the cattle industry should be considered a distinct species, C. andersoni Lindsay, Upton, Owens, Morgan, Mead, and Blagburn, 2000.

Semiclassical cross section correlations

We calculate within a semiclassical approximation the autocorrelation function of cross sections. The starting point is the semiclassical expression for the diagonal matrix elements of an operator. For general operators with a smooth classical limit the autocorrelation function of such matrix elements has two contributions with relative weights determined by classical dynamics. We show how the random matrix result can be obtained if the operator approaches a projector onto a single initial state. The expressions are verified in calculations for the kicked rotor.

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.

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.

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.

Insect peptides with improved protease-resistance protect mice against bacterial infection

At a time of the emergence of drug-resistant bacterial strains, the development of antimicrobial compounds with novel mechanisms of action is of considerable interest. Perhaps the most promising among these is a family of antibacterial peptides originally isolated from insects. These were shown to act in a stereospecific manner on an as-yet unidentified target bacterial protein. One of these peptides, drosocin, is inactive in vivo due to the rapid decomposition in mammalian sera. However, another family member, pyrrhocoricin, is significantly more stable, has increased in vitro efficacy against gram-negative bacterial strains, and if administered alone, as we show here, is devoid of in vitro or in vivo toxicity. At low doses, pyrrhocoricin protected mice against Escherichia coli infection, but at a higher dose augmented the infection of compromised animals. Analogs of pyrrhocoricin were, therefore, synthesized to further improve protease resistance and reduce toxicity. A linear derivative containing unnatural amino acids at both termini showed high potency and lack of toxicity in vivo and an expanded cyclic analog displayed broad activity spectrum in vitro. The bioactive conformation of native pyrrhocoricin was determined by nuclear magnetic resonance spectroscopy, and similar to drosocin, reverse turns were identified as pharmacologically important elements at the termini, bridged by an extended peptide domain. Knowledge of the primary and secondary structural requirements for in vivo activity of these peptides allows the design of novel antibacterial drug leads.

Analysis of maternal circulation and renal function in physiologic pregnancies; parallel examinations of the changes in the cardiac output and the glomerular filtration rate

OBJECTIVE

The aim of the study was to examine the temporal relations between the parameters of the maternal hemodynamics and homeostasis in different phases of pregnancy and the postpartum period.

METHODS

Eleven healthy pregnant women were involved in the study. The value of the peripheric vasodilatation was measured by the ratio I/A of the maternal sphygmogram (I: incisure point, A: amplitude of the carotid pressure curve). The change of the cardiac output was determined by the ejection angle composed from maternal carotid sphygmogram and its first electrical derivate (dP/dT). The glomerular filtration rate (GFR) was measured with the in vitro radiofluorescent method.

RESULTS

The primary peripheral vasodilatation and GFR increase occur early in the first trimester of a normal pregnancy, start to decrease at the end of the third trimester, and return to the normal value in the postpartum period. The increase of GFR precedes the increase of cardiac output. The cardiac output increases progressively from the first trimester and starts to decrease in the third trimester of a normal pregnancy. The extracellular volume increases at the beginning of first trimester progressively until the end of pregnancy and returns to the normal value in the postpartum period.

DISCUSSION

The increase of GFR and the cardiac output during pregnancy are contributed to volume-establishment and to the cessation of the special "underfilled" condition of the maternal circulation in the normal pregnancy. We suppose that the maximal increase of GFR precedes the maximal increase of the cardiac output because the GFR increase is caused by maximal renal vasodilatation. The increase of cardiac output is caused in the first trimester by the shunt effect of the enhanced renal blood flow of maternal kidneys, and in the second and third trimester by the shunt effect of the feto-placental unit and the shunt effect of the maternal kidneys.

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.

Morphologic, host specificity, and molecular characterization of a Hungarian Cryptosporidium meleagridis isolate

This study was undertaken in order to characterize Cryptosporidium meleagridis isolated from a turkey in Hungary and to compare the morphologies, host specificities, organ locations, and small-subunit RNA (SSU rRNA) gene sequences of this organism and other Cryptosporidium species. The phenotypic differences between C. meleagridis and Cryptosporidium parvum Hungarian calf isolate (zoonotic genotype) oocysts were small, although they were statistically significant. Oocysts of C. meleagridis were successfully passaged in turkeys and were transmitted from turkeys to immunosuppressed mice and from mice to chickens. The location of C. meleagridis was the small intestine, like the location of C. parvum. A comparison of sequence data for the variable region of the SSU rRNA gene of C. meleagridis isolated from turkeys with other Cryptosporidium sequence data in the GenBank database revealed that the Hungarian C. meleagridis sequence is identical to a C. meleagridis sequence recently described for a North Carolina isolate. Thus, C. meleagridis is a distinct species that occurs worldwide and has a broad host range, like the C. parvum zoonotic strain (also called the calf or bovine strain) and Cryptosporidium felis. Because birds are susceptible to C. meleagridis and to some zoonotic strains of C. parvum, these animals may play an active role in contamination of surface waters not only with Cryptosporidium baileyi but also with C. parvum-like parasites.

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.

Investigation of the alveolar macrophages and T lymphocytes in 15 patients with systemic sclerosis

The cell distribution and function of alveolar macrophages and T lymphocytes were investigated in the bronchoalveolar lavage (BAL) of 15 patients with systemic sclerosis (SSc). In alveolar macrophages, both spontaneous and PMA-stimulated TNF-alpha production were increased in SSc. PMA-induced IL-6 production was also elevated. Spontaneous IL-6 excretion of scleroderma alveolar macrophages was similar to the controls. Yeast and C3b-coated yeast (opsonised yeast) phagocytosis, chemotaxis and Fc receptor activity of alveolar macrophages were normal. The proportion of CD3, CD4 and CD8 T-lymphocyte subsets in the BAL was similar to the control values. The lymphocyte blast transformation index of the non-adherent cells deriving from the BAL fluid was markedly decreased.

Attempted chemoprophylaxis of cryptosporidiosis in chickens, using diclazuril, toltrazuril, or garlic extract

Three battery tests were conducted to study the anticryptosporidial efficacy of the 2 commercially available anticoccidial triazinone derivates, diclazuril and toltrazuril, and a garlic extract. At the recommended level, diclazuril reduced the oocyst output of birds by 14.6%. The efficacy of toltrazuril was 52.1% at the recommended level, which could be moderately increased using 5 or 10 times the recommended dose. However, these doses resulted in significant weight gain reduction. The efficacy of garlic extract was 24.4%. It is concluded that none of the drugs can be recommended for chemoprophylaxis or therapy of cryptosporidiosis in chickens.

High level of aspartic acid-bond isomerization during the synthesis of an N-linked tau glycopeptide

An increased degree of utilization of the potential N-glycosylation site in the fourth repeat unit of the human tau protein may be involved in the inability of tau to bind to the corresponding tubulin sequence(s) and in the subsequent development of the paired helical filaments of Alzheimer's disease. To model these processes, we synthesized the octadecapeptide spanning this region without sugar, and with the addition of an N-acetyl-glucosamine moiety. The carbohydrate-protected, glycosylated asparagine was incorporated as a building block during conventional Fmoc-solid phase peptide synthesis. While the crude non-glycosylated analog was obtained as a single peptide, two peptides with the identical, expected masses, in approximately equal amounts, were detected after the cleavage of the peracetylated glycopeptide. Surprisingly, the two glycopeptides switched positions on the reversed-phase high performance liquid chromatogram after removal of the sugar-protecting acetyl groups. Nuclear magnetic resonance spectroscopy and peptide sequencing identified the more hydrophobic deprotected peak as the target peptide, and the more hydrophilic deprotected peak as a peptide analog in which the aspartic acid-bond just preceding the glycosylated asparagine residue was isomerized resulting in the formation of a beta-peptide. The anomalous chromatographic behavior of the acetylated beta-isomer could be explained on the basis of the generation of an extended hydrophobic surface which is not present in any of the other three glycopeptide variants. Repetition of the syntheses, with altered conditions and reagents, revealed reproducibly high levels of aspartic acid-bond isomerization of the glycopeptide as well as lack of isomerization for the non-glycosylated parent analog. If similar increased aspartic acid-bond isomerization occurs in vivo, a protein modification well known to take place for both the amyloid deposits and the neurofibrillary tangles in Alzheimer's disease, this process may explain the aggregation of glycosylated tau into the paired helical filaments in the affected brains.

Study on the course of Cryptosporidium baileyi infection in chickens treated with interleukin-1 or indomethacin

The effects exerted by human recombinant interleukin-1 beta (hrIL-1 beta) and the prostaglandin inhibitor indomethacin on the course of Cryptosporidium baileyi infection in chickens were studied. Daily oocyst shedding was monitored by a quantitative method throughout the experiment. Humoral immune response to C. baileyi was assessed by ELISA at 3 weeks of age while the level of cellular immune response to phytohaemagglutinin-P (PHA-P) by a skin test at 23 days of age. Parenteral application of hrIL-1 beta decreased oocyst shedding to 62%, but the infection ran a similar course in treated and control birds. The PHA-P skin test demonstrated increased cellular immune reaction in chickens receiving IL-1 beta, but there was no significant difference in the humoral responses of the two groups as detected by ELISA. On the other hand, indomethacin mixed to the feed lessened oocyst shedding to 13.7% and also shortened its duration. Immunological parameters as reflected by PHA-P skin test and ELISA results indicated enhanced cellular but unaltered humoral immune response. These data suggest that the systemic application of interleukin-1 can induce partial protection against C. baileyi in chickens and that prolonged, abundant oocyst shedding is due to an indomethacin-sensitive immunodepression via the prostaglandin pathway.

Human Dirofilaria repens infection in Hungary: a case in the spermatic cord and a review of the literature

Orchiectomy was performed in a 37-year-old Hungarian man exhibiting a swelling in his right testicle. Histology revealed a nodule attached to the spermatic cord, consisting of a granulomatous tissue around sections of a nematode. The worm was identified as Dirofilaria repens, an uncommon parasite in Hungary. As the patient had been abroad only in Italy where cases of dirofilariosis in dogs and humans are relatively frequent, it is assumed that the infection might have been acquired in that country 5 years earlier. This is the fifth case, published so far in the world, of such a localization in a human. The human cases of dirofilariosis reported in Hungary are reviewed.

Immunogenicity of three oocyst extracts of Cryptosporidium baileyi in experimentally infected chickens

The immunogenic properties of water-soluble and detergent-extracted components of Cryptosporidium baileyi oocysts were studied. Oocyst cytosol antigen (OCA) containing hydrophilic proteins was obtained by freeze-thaw cycles in liquid nitrogen. This was followed by Triton X-114 extraction of remaining oocyst fragments to dissolve membrane-bound proteins (TRE). The remainder of the pellet was solubilized with sodium dodecyl sulfate and treated with 2-mercaptoethanol to reduce disulfide-linked oocyst wall proteins (BME). The immune recognition of these three extracts was evaluated during the course of experimental cryptosporidiosis in chickens using ELISA, immunoblotting, and the lymphocyte stimulation test (LST). Four groups of chickens were infected at various times with different doses of C. baileyi and one group with the mammalian parasite C. parvum. Analysis of the data revealed that OCA proteins are well recognized by serum antibodies during the infection and to a limited extent by sera from chickens infected with C. parvum. Humoral responses of chicken groups to this antigen did not correlate well with the length of patency in contrast with its cellular recognition in LST. TRE gave lower values than OCA in both ELISA and LST, though it was still specifically recognized by samples from C. baileyi-infected chickens. Antibodies reacted aspecifically with BME, since only samples of birds which were immunocompetent at the time of their infection were able to recognize this extract as antigen. Immunoblotting revealed more specific components in OCA than in TRE or BME.

[Preventive treatment in internal medicine by low-molecular-weight heparin (nadroparine calcium)]

On the basis of literature data the authors discuss the preventive treatment of the low-molecular-weight heparin in various non-surgical disorders. The method was compared with unfractionated heparin in the treatment of 20 high risk patients. The efficacy of the two different heparins was examined on the liver and renal function, blood lipids and the hematologic and hemostaseologic parameters. The thromboembolic and hemorrhagic complications were observed. Significant difference was not found with the comparison of the two preparations. The authors emphasize the simplicity, safety, home treatment possibility of the low-molecular-weight heparin and the regular control of thrombocyte-count only, too.

p53 protein and its messenger ribonucleic acid in human adrenal tumors

The role of p53 tumor suppressor gene in the pathomechanism of adrenal tumors was investigated by measuring p53 protein and its messenger ribonucleic acid (mRNA) in 12 normal human adrenals as well as in 56 adrenal tumors (7 aldosterone-producing adenomas, 5 adrenocortical adenomas causing Cushing's syndrome, 19 non-hyperfunctioning adrenocortical adenomas, 5 adrenocortical carcinomas, 12 pheochromocytomas, 3 myelolipomas, 4 ganglioneuromas and 1 hemangioma). The p53 protein concentration was significantly increased in aldosterone-producing adenomas (394+/-36 pg/mg cytosolic protein, mean+/-SE, vs 266+/-18 in normal human adrenals), whereas the concentration of this protein in Cushing's adenomas, non-hyperfunctioning adrenocortical adenomas, pheochromocytomas, and in all but one adrenocortical carcinomas was similar to that measured in normal human adrenal tissues. One adrenocortical carcinoma tissue showed very high p53 protein content (3000 pg/mg cytosolic protein). By contrast, myelolipomas (23+/-20) ganglioneuromas (43+/-15) and a hemangioma (11 pg/mg cytosolic protein) had very low p53 protein content. Northern blot analysis revealed the presence of p53 mRNA in each adrenal tissue examined with highest levels in aldosterone-producing and Cushing's adenomas. It is possible that the differences in p53 protein and/or mRNA contents reflect corresponding differences in the pathogenetic importance of p53 alterations in these types of adrenal tumors.

Assessment of maternal immunity to Cryptosporidium baileyi in chickens

The degree of protection to Cryptosporidium baileyi in the progeny of infected chickens was studied. Hens at the beginning of their laying period were given orally three consecutive, large doses of C. baileyi oocysts at weekly intervals. The infection became patent after 6 days and lasted for another 6 days. Increasing serum IgG, and serum, bile, lachrymal and salivary IgA were demonstrated from their samples. These immunoglobulins were transferred to the eggs, since high levels of maternally derived IgG and lower amount of IgA were present in their yolks. Hatchlings of infected hens were divided into uninfected (UY) and infected (IY) groups, the birds in the latter receiving an oral inoculum of C. baileyi oocysts on the first day of their life. Two other groups, progeny of uninfected hens served as controls (uninfected UC, and infected IC). Maternal IgG was detected in serum samples of UY hatchlings which was eliminated by the third week. The total oocyst shedding of IY chickens was 54.3% lower than that of the controls (IC), however, the prepatent and patent periods did not show significant difference. In spite of the partial protection observed in IY birds, their humoral immune response to C. baileyi was significantly lower when compared to IC. A dot-ELISA was developed to evaluate seroconversion of infected chickens which was 100% in both infected groups. The findings of the present study suggest that infection of hens with C. baileyi results in partial protection of their progeny to this parasite, and factors other than immunoglobulins may also be transferred via the eggs.

Detection of antibodies to Neospora caninum in bovine postabortion blood samples from Hungary

In order to obtain data on the occurrence of the protozoan parasite Neospora caninum as a potential factor in the aetiology of reproduction problems in cattle, 97 postabortion sera were examined by ISCOM ELISA and IFAT for the presence of antibodies in N. caninum. The results showed 10% and 9% seropositivity by the ELISA and IFAT, respectively. In 2 of the 10 seropositive cases no other fetopathogenic agents (such as Chlamydia sp., Leptospira spp. or bovine viral diarrhoea virus) were detected. These data confirm the presence of N. caninum in cattle in Hungary.

Coexpression of p53 and tissue transglutaminase genes in human normal and pathologic adrenal tissues

The presence of p53 and tissue transglutaminase (tTG) gene expressions was investigated in human normal and pathologic adrenal tissues with two aims (1) to determine the tissue content of p53 protein, its messenger ribonucleic acid (mRNA) and, especially, tTG mRNA which has not been previously reported and (2) to study possible differences in the coexpression of p53 and tTG in various adrenal disorders. Using Northern blot analysis, p53 and tTG mRNAs were detected in each adrenal tissue examined including 5 normal human adrenals, 6 aldosterone-producing adenomas, 3 Cushing's adenomas, 1 primary nodular adrenocortical hyperplasia causing Cushing's syndrome in an infant, 12 non-hyperfunctioning adrenocortical adenomas, and 4 adrenocortical carcinomas. The results showed a significant positive correlation between these two mRNAs in all adrenal tissues except adrenocortical carcinomas. Compared to normal adrenals, high p53 mRNA levels were observed in aldosterone-producing and Cushing's adenomas and, most markedly, in a tissue from a primary nodular adrenocortical hyperplasia. Also, Cushing's adenomas had significantly higher tTG mRNA contents. Immunohistochemistry for wild-type and mutant p53 protein showed numerous p53 positive cells with a strong nuclear staining in a tissue from a primary nodular adrenocortical hyperplasia, whereas the p53 positive cells were absent, except those with a faint nuclear staining, in all other adrenal tissues. However, all adrenal tissues showed detectable p53 contents by the more sensitive method of luminometric immunoassay (LIA). Using this method, aldosterone-producing adenomas exhibited significantly higher p53 contents than normal adrenal tissues. These observations may support potentially important roles for p53 and tTG in adrenal pathophysiology, especially in mechanisms which influence the evolution and/or progression of aldosterone-producing and Cushing's adenomas and, most probably, hyperplasias.

Failure to differentiate Cryptosporidium parvum from C. meleagridis based on PCR amplification of eight DNA sequences

In order to determine the specificities of PCR-based assays used for detecting Cryptosporidium parvum DNA, eight pairs of previously described PCR primers targeting six distinct regions of the Cryptosporidium genome were evaluated for the detection of C. parvum, the agent of human cryptosporidiosis, and C. muris, C. baileyi, and C. meleagridis, three Cryptosporidium species that infect birds or mammals but are not considered to be human pathogens. The four Cryptosporidium species were divided into two groups: C. parvum and C. meleagridis, which gave the same-sized fragments with all the reactions, and C. muris and C. baileyi, which gave positive results with primer pairs targeting the 18S rRNA gene only. In addition to being genetically similar at each of the eight loci analyzed by DNA amplification, C. parvum and C. meleagridis couldn't be differentiated even after restriction enzyme digestion of the PCR products obtained from three of the target genes. This study indicates that caution should be exercised in the interpretation of data from water sample analysis performed by these methods, since a positive result does not necessarily reflect a contamination by the human pathogen C. parvum.

Interaction of chicken anaemia virus and Cryptosporidium baileyi in experimentally infected chickens

The natural occurrence of concomitant chicken anaemia virus (CAV) and Cryptosporidium baileyi infection was described earlier. In this experiment, 1-day-old chickens were infected with CAV alone (anaemia virus infected, AI) or followed by inoculation with 8 x 10(5) C. baileyi oocysts orally at 1 wk of age (anaemia virus and Cryptosporidium infected, ACI). Another group of chickens received the same dose of C. baileyi oocysts without previous virus infection (Cryptosporidium infected, CI), and two groups of uninfected chickens served as controls. Except one group (uninfected control, UC), all groups -- including the other control group (challenged control, CC) -- were challenged with an oral inoculum of 8 x 10(5) C. baileyi oocysts at the age of 4 wk. Haematological, serological, immunohistochemical and pathological findings confirmed the effect of the virus agent. The individual C. baileyi oocyst shedding did not show significant difference between group CI and ACI, however, after challenge infection the AI chickens shed approximately three times more C. baileyi oocysts than those in group CC. Mortality and the percentage of birds that developed anaemia was significantly higher among ACI than AI chickens, while haematocrit values at 2 wk of age and relative bursal weights at 4 wk of age were moderately lower in the ACI group. The results presented here suggest that concurrent CAV infection increases the reproductive potential of C. baileyi in chickens, and both pathogens have synergistic effect on each other.

Effect of F-2 and T-2 fusariotoxins on experimental Cryptosporidium baileyi infection in chickens

The course of Cryptosporidium baileyi infection in chickens fed with different doses of fusariotoxins was compared with that of control groups. F-2 toxin levels of 0.187-1.5 mg kg-1 and T-2 toxin levels of 0.187-6.0 mg kg-1 were investigated. The experimental animals were orally infected with 6 x 10(5) C. baileyi oocysts at 1 week of age. Total daily oocyst output was monitored by a quantitative method. Acquired immunity was tested at the age of 4 weeks, by ELISA and by a challenge infection with an equal number of oocysts, upon recovery from the primary infection. The results show that in chickens kept on the lower doses of F-2 and T-2 toxins, the parasite infection ran a similar course to that in the control groups, and the animals became resistant to re-infection. However, when higher doses (2.0-6.0 mg kg-1) of T-2 toxin were used, a depression of weight gain was observed with some other physiological parameters (PCV, weight of bursa, weight of thymus, skin thickness in PHA-P skin test) also indicating toxic effect and, simultaneously, the oocyst output decreased significantly and the patent period was slightly prolonged. Although certain modifications of the immune response could be revealed, the chickens became resistant to re-infection. Only early (1 week of age) parasite infection and 6 mg kg-1 T-2 toxin in the feed significantly depressed body weight gain and immunity.

[Bilateral renal artery stenosis diagnosed during pregnancy]

Bilateral renal artery stenosis was diagnosed noninvasively in the 17th gestational week, in a chronically hypertensive pregnant woman, by renal artery duplex ultrasound examination, MRI and MR angiography. Continuous monitoring of the mother and the fetus was performed. Blood pressure was stabilized by complex antihypertensive therapy, but from the beginning of the third trimester superimposed preeclampsia developed gradually. In the 34th gestational week a 1600-g newborn was delivered by elective cesarean section. The case report draws attention to the significance of the thorough examination of hypertensive women before pregnancy.

Unique Alzheimer's disease paired helical filament specific epitopes involve double phosphorylation at specific sites

Alzheimer's disease (AD) paired helical filaments (PHFs), building blocks of neurofibrillary tangles (NFTs) are composed of hyperphosphorylated forms of the microtubule-associated protein tau (i.e., PHF-tau). Currently, much effort is devoted to the development of diagnostic antibodies specific for PHF-tau since elevated tau levels are found in the cerebral spinal fluid of AD patients. To this end, we have mapped the epitopes of a large panel of monoclonal antibodies (mAbs) that recognized only phosphorylation dependent epitopes on PHF-tau. These mAbs include the PHF-tau specific mAb AT10 and 12 newly developed anti-PHF mAbs that recognize PHF-tau but not autopsy-derived normal adult tau on Western-blot and enzyme-linked immunosorbent assay (ELISA). Epitope analysis, together with data on known binding sites of previously published mAbs, revealed that Ser214, Thr231, and Ser396 are immunodominant phosphorylated amino acids in PHF-tau. Six of the 12 new mAbs recognized one of these three phosphorylated sites. With the exception of AT10 and PHF-27, all the mAbs also labeled fetal tau and biopsy-derived tau. Since mAbs AT10 and PHF-27 had little or no affinity for fetal tau and biopsy tau, they can be considered as the first "true" PHF-specific antibodies capable of distinguishing tau isoforms from normal versus AD subjects, suggesting a possible utility of these mAbs as diagnostic markers. Remarkably, the true PHF-specific antibodies recognized peptide sequences phosphorylated on more than one amino acid residue. The peptide recognition of mAb AT10 required the simultaneous phosphorylation of Thr212 and Ser214, and the peptide recognition of mAb PHF-27 was markedly increased when both the primary site Thr231 and the subsite Ser235 were phosphorylated. Since AT10 and PHF-27 are the only mAbs currently available that bind specifically to PHF-tau, these data suggest that double phosphorylation at Thr212/Ser214 and Thr231/Ser235 may be unique to PHF-tau. These data may facilitate the development of mAbs that can be used as specific diagnostic reagents for the detection of altered tau in cerebrospinal fluid of AD patients.

Plasma dehydroepiandrosterone sulfate levels in patients with hyperfunctioning and non-hyperfunctioning adrenal tumors before and after adrenal surgery

To investigate the clinical significance of plasma dehydroepiandrosterone sulfate (DHEAS) measurements, 175 patients with histologically confirmed adrenal tumors, 10 cortisol-producing adenomas, 59 aldosterone-producing adenomas, 56 non-hyperfunctioning adenomas, 13 adrenocortical carcinomas, 13 adrenal cysts, and 24 adrenomedullary tumors were studied. Plasma DHEAS levels were expressed as percentage of the mean of sex- and age-matched groups of healthy, normal subjects (DHEAS %). We found that before adrenal surgery, DHEAS % values were significantly reduced in patients with cortisol-producing (mean, 15.2% of control; 95% confidence interval (CI), 9.4-24.7%), non-hyperfunctioning (28.4%; 22.4-36.0%) as well as aldosterone-producing adrenocortical adenomas (55.4%; 47.1-65.1%) compared with controls, while values were normal in patients with adrenal cysts and in those with adrenomedullary tumors. Plasma DHEAS % values exhibited a great variability in adrenocortical carcinomas (mean, 84.0%; 95% CI, 33.2-212.5%). Death from adrenocortical carcinoma was more frequent in patients with high plasma DHEAS % values compared with those with low DHEAS %. During long-term postoperative monitoring, we found that plasma DHEAS levels of patients with aldosterone-producing and non-hyperfunctioning adenomas returned to normal in the second and fourth postoperative year respectively. In patients with cortisol-producing adenomas, plasma DHEAS remained suppressed for as long as 8 years after the operation. These findings show that except in adrenocortical carcinomas and cysts, plasma DHEAS levels are significantly decreased in all groups of adrenocortical tumors, including non-hyperfunctioning and aldosterone-producing tumors. The extent of this decrease and the postoperative persistence of suppressed plasma DHEAS levels may be related to the glucocorticoid production of adrenocortical tumors.

Detection of Cryptosporidium parvum DNA in formed human feces by a sensitive PCR-based assay including uracil-N-glycosylase inactivation

We developed a PCR-based method that can be used to identify Cryptosporidium parvum in human feces. Fecal oocysts were concentrated by centrifugation on a sodium chloride gradient and filtration on a nitrocellulose filter prior to DNA extraction and PCR amplification of a 452-bp C. parvum-specific DNA sequence with a protocol including dUTP and uracil-N-glycosylase. All samples obtained from naturally infected humans (n = 10), calves (n = 4), and goats (n = 2) were positive. A 100% detection rate was achieved with both formed and solid stools (n = 10) seeded with 1,000 C. parvum oocysts per g. Procedures based on stool concentration by a modified Ritchie method and subsequent oocyst identification by immunofluorescent labeling or acid-fast staining require concentrations of 50,000 to 500,000 oocysts per g to achieve a 100% detection rate with formed stools. The described PCR-based assay thus has a 50- to 500-fold increase in sensitivity compared to those of the methods commonly used to analyze formed feces.

Attempts to immunize chickens against Cryptosporidium baileyi with C. parvum oocysts and Paracox vaccine

To study the possibility of immunization against Cryptosporidium baileyi Current, Upton et Haynes, 1986 with the attenuated anticoccidial vaccine, Paracox and oocysts of C. parvum Tyzzer, 1912, chickens were inoculated orally with either 3 x 10(3) vaccine oocysts or 8 x 10(5) C. baileyi or C. parvum oocysts at 1 week of age. The inoculation with Paracox vaccine and C. parvum oocysts was repeated at 2 and 3 weeks of age. Uninfected birds served as controls. All animals with the exception of one uninfected group were challenged orally with either 8 x 10(5) C. baileyi or 3 x 10(5) Eimeria tenella Railliet et Lucet, 1891 oocysts at 4 weeks of age. Sera were collected at 4 weeks of age, and were examined by ELISA using C. baileyi antigens. Birds inoculated with C. parvum oocysts did not shed C. parvum oocysts in their faeces, but anticryptosporidial antibodies could be detected in the sera. The total oocyst output of C. parvum inoculated chickens was 17% of that of previously uninfected birds after the oral challenge with C. baileyi. Considering that antibodies play no or only a minor role in resistance to C. baileyi, these results suggest that inoculation of chickens with C. parvum oocysts stimulated also cellular immune response. Based on the relative body weight gain, faecal scores, oocyst output, mortality, and caecal lesions in the birds immunized with Paracox vaccine and challenged with E. tenella, the vaccination induced only a moderate protection against the reinfection. The results of cross-immunization of chickens with Eimeria spp. and C. baileyi suggest that attenuated anti-eimerian vaccines do not induce any protection against cryptosporidial infection.

Oxidative stress and antioxidant defense mechanism in glomerular diseases

The changes in red blood cell (RBC) lipid peroxidation [measured via the malonyl dialdehyde (MDA) concentration], reduced (GSH), and oxidized glutathione (GSSG) levels, hemoglobin (Hb) oxidation and antioxidant enzyme [catalase (Cat), glutathione peroxidase, and superoxide dismutase (SOD)] activities were studied in 45 pediatric patients with various glomerular diseases [minimal change nephrotic syndrome (MCNS) in relapse or in remission, lupus nephropathy (SLE), poststreptococcal glomerulonephritis (APSGN), IgA nephropathy (IGA gn)], and in 20 adult patients with IGA gn and also in 15 pediatric and 14 adult controls. The in vitro effects of hydrogen peroxide [acetyl phenylhydrazine (APH) test] on the GSH and Hb metabolisms were likewise investigated. There was an increased oxidative stress in MCNS with relapse, IGA gn, SLE gn, and APSGN, which could be detected in the GSH and Hb oxidation and in the lipid peroxidation on the peripheral RBC-s. The RBC SOD and Cat activities were significantly lower in all patients than in the controls. The RBC GSSG level was significantly elevated in all patients, with the exception of MCNS in remission. This stimulated a compensatory GSH production in MCNS with relapse and in IGA gn, but not in SLE or APSGN. The regeneration of GSH from GSSG was reduced in MCNS with relapse, SLE, and IGA gn, but not in APSGN. In remission, the GSH-GSSG redox system normalizes, but in vitro the APH test stimulates an intensive Hb oxidation. In conclusion, there is a correlation between the presence of active glomerular disease and the evidence of oxidative changes in the various parameters measured in peripheral RBCs.

The effects of post-translational side-chain modifications on the stimulatory activity, serum stability and conformation of synthetic peptides carrying T helper cell epitopes

Peptides 31D and VF13, corresponding to the rabies virus nucleo- and glycoproteins, respectively, vigorously stimulate T helper cells of the appropriate specificity. Earlier we showed how internal and external glycosylation affects the major histocompatibility complex molecule (MHC)-binding ability and conformation of these T-cell epitopes (Otvos et al. (1994) Biochim. Biophys. Acta 1224, 68-76; Otvos et al. (1995) Biochim. Biophys. Acta 1267, 55-64). In the current report, we examined the T-helper cell stimulatory ability after introduction of a new set of post-translational modifications. To obtain general information concerning the effects of amino acid side-chain modifications on other biochemical properties of protein fragments, we studied the serum stability and the conformation of the 31D and VF13 peptides. We found that the extent of the reduction of the T-cell stimulatory activity depends upon the location in the sequence of the host amino acid residue. Generally, beta-linked sugars in mid-chain positions had a greater inhibitory effect than alpha-linked sugars attached to identical amino acids. In a case where mid-chain glycosylation just marginally reduced the T-cell stimulatory activity, the beta-linked glycopeptide was significantly more resistant to serum proteases. This finding suggests that addition of beta-linked carbohydrates might be superior to the addition of alpha-linked sugars for vaccine development, and generally for peptide agonist drug design. In addition, data presented here provide the first documentation that phosphorylation and sulfation of tyrosine residues may retain the MHC-binding ability and T-cell stimulatory activity of class II epitopes. The sulfated and the phosphorylated 31D peptides exhibited considerably increased serum stability compared to the unmodified parent peptide. Finally, all post-translational modifications destabilized the dominant alpha-helical or turn structures of the peptides presented in aqueous trifluoroethanol mixtures. While the circular dichroism spectra of the alpha- and beta-linked VF13 glycopeptides with monosaccharides were almost indistinguishable, the structure of the glycopeptides depended upon the length of the sugar moiety. Significantly, incorporation of sulfate or phosphate groups resulted in identical peptide conformations.

[Endocrinologic complications of neurofibromatosis type 1]

Neurofibromatosis type 1 is the most common autosomal dominant inheritable disease, which is often associated with secondary forms of hypertension and with tumors of neuroectodermal origin. The authors present the results of evaluation of 60 members of 3 families. Of the 60 family members, 13 subjects had symptoms of neurofibromatosis type 1 disease, of which 7 subjects were evaluated. The case histories of patients are discussed: (1) An incidentally discovered adrenal tumor was proved to be a pheochromocytoma. (2) Because of complaints similar to thyrotoxicosis, thyrostatic drugs were administered for years without effect and, finally, an adrenal phaeochromocytoma was diagnosed after the presence of neurofibromatosis was established. (3) Preeclamptic pregnancy of a young primigravida complicated with severe HELLP syndrome (hemolysis-elevated liver enzymes-low platelet count) led to thorough evaluation which revealed renal artery stenosis. In this patient, percutaneous renal artery angioplasty resulted in a complete cessation of hypertension. (4) Glucocortocoid replacement therapy in a patient with neurofibromatosis type 1 resulted in a complete normalization of both secondary adrenal insufficiency and a previously unexplained iron-refractor iron-deficient anemia. The case histories of the patients demonstrate a lack of in-depth knowledge of neurofibromatosis in clinical practice. A regular follow-up of neurofibromatosis patients is suggested in specialized health centers.

Attempts to immunize chickens with Cryptosporidium baileyi oocyst extract

In order to study the possibility of immunization against Cryptosporidium baileyi with extracted crude antigen, Arbor Acres chickens were injected intramuscularly with 80 micrograms of C. baileyi oocyst-derived proteins (uninfected immunized, UI) or inoculated orally with 8 x 10(5) viable C. baileyi oocysts (infected control, IC) at 1 wk of age. The immunization was repeated in the UI group at 2 wk of age. Uninfected (UC) birds served as controls. All animals in UI, IC, and UC groups were challenged orally with 8 x 10(5) C. baileyi oocysts at the age of 4 wk. Blood samples were collected when birds were 4 and 6 wk of age, and sera were examined by enzyme-linked immunosorbent assay for the presence of antibodies against C. baileyi. Total oocyst output of UI chickens was about 60% of that of UC birds after challenge, and the prepatent and patent periods were nearly identical in the latter 2 groups. In contrast, IC birds developed complete resistance to challenge infections. These results suggest that immunization with the oocyst extract of C. baileyi may confer some degree of protection against oral challenge; however, the protection is less effective than that induced by primary oral infection. The lack of significant difference between the antibody responses of IC and UI animals to C. baileyi at 2 wk of age suggests that serum antibodies play little role in acquired resistance to challenge infection.

Poly (DL-lactide-co-glycolide) microspheres as carriers for peptide vaccines

Peptides carrying an immunodominant T-helper cell epitope delineated from the rabies virus nucleoprotein either alone or in combination with a linear B-cell epitope from the same protein were incorporated into three different formulations of poly(DL-lactide-co-glycolide) (PLG) which were distinct in their composition, and consequently in their peptide release rates. In vitro peptides incorporated into any of the PLG formulations stimulated a peptide-specific T-cell line. Upon subcutaneous immunization of mice, the PLG formulation that showed the fastest peptide release rate induced the best immune response. This immune response was in magnitude comparable or even superior to that induced by peptide emulsified in complete Freund's adjuvant.

Effects of bursectomy and thymectomy on the development of resistance to Cryptosporidium baileyi in chickens

Comparisons were made between the course of infection with Cryptosporidium baileyi in normal chickens and in chickens with functional deficiencies in either B-lymphocytes (bursectomized) or T-lymphocytes (thymectomized). Bursectomy did not influence the acquired immune response to C. baileyi infection as measured by the oocyst excretion. However, the total oocyst output of bursectomized birds was less than a quarter of that of the controls due to the reduced site for multiplication of the parasite. The total oocyst output of thymectomized chickens was more than 2 times higher and the patency was 2 times longer as compared with control animals. Moreover, thymectomized birds failed to acquire resistance to the challenge infection. These findings attest to the primary role of cell-mediated immunity in the expression of resistance to C. baileyi as opposed to the antibody-mediated mechanisms.

Remodelling of septal branch of coronary artery and carotid artery in L-NAME treated rats

Coronary and carotid artery structure was studied in rats in order to analyze the processes in the cardiovascular system in NO-deficient hypertension model. Long-term inhibition of NO synthase was induced by L-nitro arginine methyl ester (L-NAME, 50 mg/kg/day p.o.) for a period of 8 weeks. An increase in blood pressure and heart/body weight ratio confirmed the reliability of the model. The wall thickness as well as the calculated wall area of the coronary artery increased by 70% and 50%, respectively, in comparison to control vessels. The wall thickness and the calculated wall area of the carotid artery increased by 73% and 70%, respectively. Further analysis indicated that both the tunica intima and tunica media in the coronary and the carotid artery increased quantitatively in a similar manner. Remarkable differences were found in the contribution of cellular and noncellular components in the tunica media of the coronary and carotid arteries of experimental animals. The calculated extracellular area increased by 116% in comparison to the control coronary artery and by 97% in comparison to the control carotid artery. The increase in extracellular matrix of the tunica media of coronary and carotid arteries seems to be basic cause of the remodelling of the vessels studied.

Age-dependent resistance to Cryptosporidium baileyi infection in chickens

The age-dependent aspects of resistance to Cryptosporidium baileyi were studied in chickens orally inoculated with C. baileyi oocysts at 1 and 9 wk of age. The prepatent period was significantly shorter and the patency was significantly longer in younger birds. Chickens infected at 1 wk of age excreted 3 times the number of oocysts excreted by those inoculated at 9 wk of age. There was a good correlation between the length of the patent period and the total oocyst output of chickens. These results indicate that both innate and acquired resistance to C. baileyi are age-related. The numbers of animals needed per experimental group to estimate the length of the prepatent period, the patency, and the total oocyst output were assessed. Relatively small numbers of animals are required for the estimation of the mean length of the prepatent period, in contrast with the large numbers of birds needed for the estimation of the mean length of the patent period or that of the total oocyst excretion.

Potentiation of ionophorous anticoccidials with dihydroquinolines: compatibility of lasalocid and semduramicin with duokvin

Three battery tests were conducted to reveal whether or not there is an interaction between the new dihydroquinoline antioxidant, duokvin and lasalocid or the new anticoccidial, semduramicin, similar to that observed with some other ionophorous anticoccidials. In terms of body weight gain, no significant difference due to toxic interaction between duokvin and any dose of lasalocid or semduramicin was detected in chickens experimentally infected with oocysts of Eimeria tenella and E. mitis. Anticoccidial efficacy at reduced doses of both lasalocid and semduramicin in combination with duokvin showed numerical improvement; however, this again proved to be insignificant. The lack of incompatibility of this antioxidant with lasalocid or semduramicin allows their simultaneous administration on the one hand, but it fails to enable a substantial reduction of the chemoprophylactic concentration of anticoccidials in the broiler ration on the other.

Potentiation of ionophorous anticoccidials with duokvin: battery trials against Cryptosporidium baileyi in chickens

Three battery tests, employing 444 Arbor Acres chickens, were conducted to study the anticryptosporidial efficacy of the polyether ionophorous anticoccidials alone and in combination with a new dihydroquinoline antioxidant, duokvin. The following efficacy percentages for the ionophores at the recommended level were established on the basis of oocyst output: lasalocid 45, monensin 37, semduramicin 29, narasin 23, and maduramicin and salinomycin 21. The efficacy of the ionophores, with the exception of lasalocid, could be increased to 36-88% by combination with duokvin. However, these combinations resulted in a significant weight gain reduction due to toxic interaction. Efficacy showed a strong negative correlation with body weight gain and bursa weight, suggesting an indirect mode of action against the parasite. It has been concluded that neither ionophorous anticoccidials nor their combinations with duokvin can be recommended for chemoprophylaxis against avian cryptosporidiosis.