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The aim of this study was to determine accumulation of heavy metals and metalloids which are widely distributed in the environment and in food chain using wild edible mushrooms belonging to the Boletaceae family mushrooms. In addition, methanol extracts of mushrooms were tested for

This paper deals with the analysis of development and the features of traditional two-story ruralhouses built in central part of Kosovo and Metohija between the First and the Second World War.The study based on in-situ explorations and literature review has revealed the values of thesetraditional examples in terms of spatial organization, architectural style, principles of construction,and sustainability-related characteristics. In particular, the study has been deepened on the case ofthe house of Petković family in Laplje Selo, thus acknowledging the details of this residential type.

Hand injuries in agriculture represent an important medical, social and economical issue. They are mutilating, characterized by great tissue destruction, multiple finger amputations, limited possibilities of reconstruction and high risk of infection. The aim of this paper was to show the specificities of hand injuries in agriculture in relation to hand injuries of other aetiology. We analyzed patients that were treated in the Department of plastic and reconstructive surgery- Clinical centre of Vojvodina from 2004 to 2014. We noticed that trend of hand injuries in agriculture is constant during this ten year period with dominant involvement of middle aged men, more severe injuries, finger amputations and tissue damage that required more complex reconstructive procedure and longer hospitalization. Injured men are often not able to continue doing the same job and that can have great economic influence on whole family. Medical treatment of these injuries is long and expensive and results are often not favourable for patient.

The effect of age on the diversity of the murine Ig heavy chain repertoire has been studied in unimmunized C57BL/6 mice. We examined the heterogeneity of complementarity-determining region 3 (CDR3) sizes of Ig mRNA of the IgM and IgG isotypes using two VH families, VHJ558 and VHQ52, which together account for approximately 65% of the Ab repertoire. The broad and bell-shaped profiles representing the diversity of the VHJ558 family in the spleen of 2- to 6-mo-old C57BL/6 mice becomes significantly less diverse after 12 mo of age and by 18 mo of age, single CDR3 sizes that dominate the profiles can be observed in the spleens of > 85% of the mice. Readable sequences have been obtained from 40 dominant mRNA CDR3 size species indicating that they represent clonal populations of B lineage. There are no significant homologies among these sequences. Clones of B lymphocytes that express a dominant CDR3 mRNA species can also be found in the bone marrow, the mesenteric lymph nodes, and the thymus of C57BL/6 mice > 18 mo of age. Some clones of B cells can be detected in only one lymphoid compartment; others are found in two or more compartments. The splenic B cell clones in C57BL/6 mice > 18 mo of age are stable for at least 2 mo. The CDR3 mRNA species that dominate the splenic repertoire of Ig mRNA-expressing cells in vivo do not dominate the repertoire of splenic B cells activated in vitro by bacterial LPS, suggesting that they represent a modest population of B cells expressing high levels of Ig mRNA.

Apoptosis plays an essential role in the development and homeostasis of the immune system. During lymphocyte development, potentially autoreactive cells are eliminated via the activation of a tightly regulated cell death program(s). Similar processes operate in mature lymphocytes, to control the magnitude of the normal immune response by eliminating activated lymphocytes. However, differences in susceptibility to signal-induced apoptosis between immature and mature lymphocytes are numerous. One well-characterized example occurs in response to Ca2+ elevation: peripheral T lymphocytes are resistant, while immature thymocytes are highly susceptible, to Ca2+-mediated cell death (CMCD). In this study, we show that the immunosuppressant cyclosporin A (CsA) primes splenic lymphocytes to undergo CMCD upon ionomycin stimulation. This CsA-induced CMCD affected both T and B lymphocytes. CsA-plug Ca2+-mediated apoptosis was dissected into a two-step process: first, CsA and Ca2+ synergized to induce TGF-beta 1 secretion by B cells; and then TGF-beta 1 and Ca2+ synergistically triggered T and B lymphocyte apoptosis. Together, our results suggest that lymphocyte apoptosis may play a role in CsA-induced immunosuppression via a TGF-beta-dependent mechanism.

In young sugar beet plants cadmium suppressed the activity of nitrate reductase, glutamine synthetase and glutamate dehydrogenase, whereas sulphur exhibited a protective role towards activity of these enzymes, except of glutamine synthetase. Protein synthesis was suppressed in the absence of S in nutrient medium; the lowest level was at 10-3 M Cd2+. Chloroplast pigment contents were increased by S while Cd2+, even in the lowest concentration, (10−5 M) showed a repressive effect. The highest concentrations of Cd2+ (10−3 M) caused a decrease in dry mass, whereas S induced its increase. Nitrate content was increased in the presence of Cd2+ and decreased by increased concentration of S.

Mice defective in Fas-mediated apoptosis (lpr phenotype) have an intrinsic B cell abnormality that predisposes them to autoantibody production. To investigate potential roles for the Fas receptor (FasR) in B cell tolerance, FasR expression and function were evaluated at different stages of B cell development. FasR expression was very low or absent on pro- and pre-B cells, but was detected in early B cell lines and was up-regulated following IFN-gamma-induced maturation of the pre-B cell line 70-Z. Whereas FasR expression was very low in resting mature sIgM+ B cells, expression was markedly increased following mitogen activation and was also elevated in two mature sIgG+ lymphoma lines. FasR expression correlated strongly with the ability of B cells to undergo Fas-mediated apoptosis. In addition, although Fas did not appear to play a direct role in apoptosis mediated by cross-linking of sIg with anti-IgM, anti-FasR and sublethal concentrations of anti-Ig were additive in the induction of apoptosis in the early B cell line WEHI 231. These findings suggest that the Fas pathway is not involved in the elimination of pro- and pre-B cells, but are compatible with an ancillary role for FasR in the elimination of early B cells and elimination of mature B cells following activation.

We have previously isolated, and characterized in vitro, two subsets of CD4hi T cell receptor (TCR)hi single positive (SP) thymocytes: CD8- and CD8lo. In this report, we have analyzed phenotypic, functional, and developmental characteristics of these "late" CD4hi SP thymocyte subsets. The TCRhi phenotype and the elimination of T cells expressing TCR V beta segments reactive with endogenous mouse mammary tumor virus (MMTV) products suggested that both subsets had undergone positive and negative selection. CD8-4hi thymocytes were functional, as judged by their ability to: (a) induce lethal graft versus host disease (GVHD); (b) survive and expand in peripheral lymphoid organs; and (c) proliferate, rather than undergo apoptosis, in response to in vitro TCR cross-linking. By contrast, CD8lo4hi cells could not induce GVHD, were unable to expand (and perhaps even survive) in peripheral organs and underwent apoptosis upon TCR cross-linking. However, when reintroduced into the thymus, these cells matured into functional, long-lived CD8-4hi lymphocytes. These results document an obligatory requirement for the thymic microenvironment in the final maturation of the majority of CD4hi SP postselection thymocytes, and demonstrate the existence of a previously unrecognized control point in T cell development.

Fas-deficient lpr and gld mice develop lymphadenopathy due to the accumulation of T cells with an unusual double negative (DN) (CD4-CD8-) phenotype. Previous studies have shown that these abnormal cells are capable of inducing redirected lysis of certain Fc receptor-positive target cells. Since the Fas ligand (FasL) has recently been shown to be partly responsible for T cell-mediated cytotoxicity, lymph node cells from lpr and gld mice were examined for the expression of FasL mRNA. Northern blot analysis revealed that lymph node cells obtained from lpr and gld mice had a striking increase in the level of expression of FasL mRNA predominantly due to expression in the DN T cells. Furthermore, lpr, but not gld lymph node cells killed the B cell line, A20, in a Fas-dependent manner. These findings indicate that Fas mutations result in a massive up-regulation of FasL which, most likely, results from repetitive exposure to (self) antigen. This phenomenon could explain the lpr-induced wasting syndrome observed when lpr bone marrow-derived cells are adoptively transferred to wild-type recipients.

CD8lo4lo cells are the immediate precursors of immature CD8hi4loTcRlo, CD8lo4hiTcRlo and CD8hi4hiTcRlo double-positive (DP) thymocytes in the adult murine thymus. These cells are the first subset in the adult thymus to express accessory CD8 and CD4 molecules, to rearrange the T cell receptor (TcR) alpha chain genes and to express the TcR alpha beta heterodimer at low levels at the surface. Here, we investigate the fetal ontogeny of CD8lo4lo cells. We detect these cells on day 15 of fetal development. They dominate the thymus on day 15.5, to become progressively less prominent thereafter. An important characteristic of fetal CD8lo4lo cells is the early expression of TcR alpha mRNA (on fetal day 15, 36-48 h earlier than reported previously). Our results also suggest, but do not prove, that the receptor may be expressed on the surface as early as day 15.5. Fetal CD8lo4lo cells, like their adult counterparts, become DP in vitro. However, early fetal CD8lo4lo thymocytes express both CD44 and CD25--unlike the adult subset--and that links them to their putative precursors, fetal CD44+CD25+ double-negative cells. This finding underscores the difference between adult and fetal thymocytes in turnover of membrane molecules and/or the kinetics of progression through phenotypic stages.

The motives for performing conservation surgery in tumors of the upper urinary tract are progressive renal failure associated with those tumors, frequent bilateral tumors, and tumors on solitary kidney, which does not always comply with the patho-anatomic characteristics of the tumor and possibilities of this type of surgery. The aim of the study was to separate the real indications for the application of this therapy, independently of the expected quality of life after the operation. Out of 682 patients with upper urothelial tumor conservation surgery was performed in 161 patients. The indications were characterized as "real", oncologic in 121 patient, and in 40 patients (25%) the main reason was preservation of quality of life. During the five-year follow-up period recurrence developed in 17% of patients in the group with oncologic indications, "real" indications, and in as much as 40% of patients from the group in with the main reason was preservation of quality of life. Thus, the oncologic indications must be primary in reaching the decision for conservation surgery in tumors of the upper urinary tract, and the quality of life should be an additional motive for this therapy.

The murine class I molecule H-2Kb and its natural gene conversion variant, H-2Kbm8, which differs from H-2Kb solely at 4 aa at the bottom of the peptide-binding B pocket, are expressed in coisogenic mouse strains C57BL/6 (B6) and B6.C-H-2bm8 (bm8). These two strains provide an excellent opportunity to study the effects of Mhc class I polymorphism on the T cell repertoire. We recently discovered a gain in the antiviral CTL repertoire in bm8 mice as a consequence of the emergence of the Mhc class I allele H-2Kbm8. In this report we sought to determine the mechanism behind the generation of this increased CTL diversity. Our results demonstrate that repertoire diversification occurred by a gain in intrathymic positive selection. As previously shown, the emergence of the same Mhc allele also caused a loss in positive selection of T cell repertoire specific for another Ag, OVA-8. This indicates that a reciprocal loss-and-gain pattern of intrathymic selection exists between H-2Kb and H-2Kbm8. Therefore, in the thymus of an individual, a new Mhc allele can select new T cell specificities, while abandoning some T cell specificities selected by the wild-type allele. A byproduct of this repertoire shift is a net gain of T cell repertoire of the species, which is likely to improve its survival fitness.

Cytotoxicity is a major effector function of CD8(+) T cells. Although mitogen-activated protein kinase (MAP kinase) / extracellular regulatory kinase (ERK) activity is indispensable for cytotoxic activity of most CD8(+) T cells a portion of CD8(+) T cells appears resistant to MEK inhibition as cytotoxicity of bulk cultures was partially preserved in the presence of a MEK inhibitor. We have also identified a long-term CD8(+) T cell line with unaltered cytolytic activity after prevention of ERK activation. Antigen-induced microtubule organizing center (MTOC) reorientation was not prevented in this CD8(+) cell line by MEK inhibition, in sharp contrast to the MTOC reorientation prevention in a CD8(+) T cell clone with MEK inhibition-sensitive cytolytic activity. These findings suggest that resistance of lysis to MEK inhibition may be due to a lack of ERK control over MTOC reorientation in some CD8(+) T cells. Thus, there appears to be a heterogeneity of ERK-regulated cytolytic activity in CD8(+) T cells, most likely resulting from a differential control of ERK over MTOC motility.

After puberty, the thymus undergoes a dramatic loss in volume, in weight and in the number of thymocytes, a phenomenon termed age-associated thymic involution. Recently, it was reported that age-associated thymic involution did not occur in mice expressing a rearranged transgenic (Tg) TCRalphabeta receptor. This finding implied that an age-associated defect in TCR rearrangement was the major, if not the only, cause for thymic involution. Here, we examined thymic involution in three other widely used MHC class I-restricted TCRalphabeta Tg mouse strains and compared it with that in non-Tg mice. In all three TCRalphabeta Tg strains, as in control mice, thymocyte numbers were reduced by approximately 90% between 2 and 24 mo of age. The presence or absence of the selecting MHC molecules did not alter this age-associated cell loss. Our results indicate that the expression of a rearranged TCR alone cannot, by itself, prevent thymic involution. Consequently, other presently unknown factors must also contribute to this phenomenon.

The majority ( approximately 70%) of postselection CD4(+) single-positive (SP) thymocytes are CD8(lo)CD4(hi). These cells express very low levels of CD8, undetectable by flow cytofluorimetric (FCM) analysis, but sufficiently high to allow purification by panning. Unlike the fully mature CD8(-)CD4(hi) thymocytes, which account for the remaining approximately 30% of the SP CD4(+) thymocytes, CD8(lo)CD4(hi) cells are functionally immature and short-lived unless they receive an unidentified maturation signal from the thymus. In this study, we tested the hypothesis that this signal is provided by a T cell receptor (TCR)-major histocompatibility complex (MHC) class II interaction. Using intrathymic transfer, we show that the immature CD8(lo)CD4(hi) cells could complete their intrathymic maturation and populate the peripheral lymphoid organs in the absence of MHC class II (and class I) molecules. Furthermore, in mice devoid of class II (and class I) molecules, the progeny of CD8(lo)CD4(hi) cells was long-lived and functionally reactive to allogeneic class II molecules, although their numbers in the spleen and the mesenteric lymph node were approximately 40-50% lower than those in class II(+) mice 5 mo after transfer. Control experiments demonstrated that the surviving cells did not originate from the contaminating mature thymocytes. These results demonstrate that the final maturation, proliferation, and peripheral survival (up to 5 mo) of at least some postselection CD4(+) SP cells do not require the TCR-MHC class II interaction. They also indicate that the TCR-MHC class II interaction(s) required for the intrathymic development of long-lived CD4(+) SP cells occurs before the CD4(hi) SP stage of development.

This paper is a review of the patients with multiple myeloma, hospitalized at Clinic of Haematology in Sarajevo during the period from 1993 to 1998. This study encircles 45 patients; 18 males (40%) and 27 females (60%). Clinical and laboratory records, etiology, cytomorphology and radiography were analyzed in detail. The age of patients was 59.4 years (both males and females). The trends of disease showed increasing in 1994, 1997 and 1998, comparing it with other haematological malignancies (in 1993 the percent was 5.41, in 1998 was 15.83, and the average level, during the analyzed period, was 11.34%). The patients usually came in the terminal phase and that is the reason why median survival was 12 months. According to the results, the authors make a conclusion that there are some characteristics of this disease in individuals, comparing them with the results shown in relevant studies. They find the explanation in the exposure of the population to the chronic stress and deficit of energy caused by malnutrition during the aggression against Bosnia and Herzegovina.

Following subcutaneous implantation, the murine lymphoma E.G7 [a variant of EL-4, transfected with the chicken ovalbumin (OVA) gene] up-regulates the CD4 molecule. We previously showed that the administration of an anti-CD4 monoclonal antibody (mAb) to EG.7-bearing mice leads to a rapid and complete regression of large established tumors. This tumor regression was shown to require both CD8+ cells and functional Fcgamma receptors (FcgammaR), as it failed to occur in mice depleted of CD8 cells, or mice genetically deficient in FcgammaI/III (gamma-/-mice). Using adoptive transfer, we now show that the FcgammaR+ cells required for this regression are the CD11b+ (phagocytic) cells. Furthermore, experiments using peptide tolerization demonstrated that the critical CD8 CTL population in this model is tumor specific. Analysis of tumors at various stages of regression revealed a massive CD11b+FcgammaR+ and a marginal CD8 infiltration. In the presence of the CTL determinant OVA-8 on tumor cells and of the antitumor mAb, this CD8 infiltration became remarkable, and correlated with tumor regression. These results identify the specific cellular effectors essential for the mAb-mediated tumor regression, and suggest that FcgammaR-activated macrophages induced an expansion of tumor-eliminating CTL in situ.

Chronic ethanol abuse is associated with increased activity of the microsomal ethanol-oxidizing system. This effect is due primarily to induction by ethanol of a specific cytochrome P450 (CYP2E1) responsible for enhanced oxidation of ethanol and other P450 substrates and, consequently, for metabolic tolerance to these substances. Furthermore, cytochrome 450 induction increases the activation of numerous xenobiotics to toxic metabolites and of chemical carcinogens to reactive metabolites, thereby accelerating their adverse effects. Microsomal enzyme induction has been associated with increased reactive oxygen species production and enhanced lipid peroxidation, as well as with decreased enzymatic and nonenzymatic scavenger activity, providing another possible explanation for ethanol-mediated toxicity. Yet another effect of chronic alcohol abuse is chronic immune system activation, which is the mechanism underlying alcohol-related liver disease. The metabolism of steroids and vitamins is catalyzed by P450 and is altered in chronic alcoholics. This article reviews recent advances in the understanding of ethanol interactions with drugs, toxic agents, and carcinogens, as well as with steroids and vitamins.

Arginase (EC 3.5.3.1) is one of the essential enzymes in the terminal stages of the urea cycle in the liver which participates in the elimination of ammonia from the human body [1, 7]. Except in liver tissue arginase is also present in many human tissues and in the circulating blood cells, especially in erythrocytes and leukocytes. Arginase splits arginase to urea and ornithine that serve for biosynthesis of amino acid proline, glutamic acid and biosynthesis of polyamines-spermine, spermidine and putrescine. Arginase activity is high during the mitotic cycle, with the function in phase S of the cell cycle. The aim of our study was to assess the arginase activity in the blood of children with some haematologic diseases.We examined the arginase activity in blood plasma and erythrocytes of children who suffer from some haematological disorders (27 patients) and in healthy children (control group-15 subjects). The enzyme activity was measured with spectrophotometric method on the basis of the determination of the amount of liberated ornithine from substrate-arginine [3].The obtained results suggest that arginase activity was much higher in the blood of ill children (Table 1 and Figure 1). In the control group of children (total 15) plasma arginase activity was in the range of 0 to 20 U/L x = 0.86 U/L), and enzyme activity in erythrocytes was 1.62-3.98 U/g Hb (x = 2.81 U/g Hb). Erythrocytes enzyme activity and plasma enzyme activity were in ranges of 4.03-5.26 U/L with the mean value of x = 4.56 U/L, and arginase activity in erythrocytes was in ranges of 9.38-14.16 U/g Hb, with mean value x = 11.34 U/g Hb, respectively. Arginase activity in erythrocytes was also significantly higher in children with non-spherocytic haemolytic anaemia (9 children) and was in ranges of 5.33-9.58 U/g Hb (x = 7.29 U/g Hb), with the relatively low values in plasma, 0-4.14 U/L (x = 1.75 U/L). In children with sideropenic anaemia (total number-11) arginase activity in erythrocytes was also very significantly increased with the range between 2.86 and 14.16 U/g Hb (x = 5.54 U/g Hb) while the plasma enzyme activity was relatively low, with the values in range of 0-4.98 U/L (x = 1.41 U/L); in myelodysplastic syndrome (4 pts) arginase activity in plasma was very low (0-0.71 U/L; x = 0.26 U/L) with higher values of arginase activity in erythrocytes (4.22-5.89 U/g Hb; x = 4.94 U/g Hb).We have concluded that the enzyme activity was the highest in erythrocyte haemolysates of patients with spherocytosis, non-sherocytic haemolytic anaemia; it was also high, but in a smaller degree, in erythrocytes of children with sideropenic anaemia and myelodysplastic syndrome; arginase activity in plasma of these children was higher in comparison with enzyme activity in plasma and erythrocytes of healthy children. Our results are in agreement with data from literature where it is stated that the younger erythrocytes have the highest arginase activity than the mature erythrocytes [4].The measurement of arginase activity in plasma and erythrocytes is a good diagnostic indicator for the presence of young erythrocytes and reticulocytes in the circulating blood as is the good sign for the detection of haemolytic processes.

DNA immunization has been shown to elicit both antibody and CTL responses against antigens expressed by infectious organisms. Because CTL responses have been implicated in rejection of cancer, we investigated whether DNA immunization by particle bombardment using a gene gun could induce CTL responses that were capable of rejecting tumors in mice. DNA immunization by particle bombardment using genes encoding beta-galactosidase and ovalbumin primed mice to generate CTLs in two genetic backgrounds (DBA/2 and C57BL/6 strains, respectively). DNA immunization was more potent in inducing CTLs than immunization with an optimized regimen of ovalbumin peptide plus immune adjuvant. Immunity induced by DNA immunization protected mice against s.c. challenge with tumors expressing the beta-galactosidase antigen. Tumors were rejected even when DNA immunization was started 3 or 7 days after tumor challenge as tumors were becoming established. Tumor rejection required CD8(+) T cells, confirming a role for CTLs in vivo. These studies show that DNA immunization by particle bombardment can efficiently induce CTL responses that are capable of rejecting even established tumors.

The immunodominant ovalbumin257‐264 (OVA-8, SIINFEKL) and herpes simplex virus gB496‐503 (HSV-8, SSIEFARL) peptides share 50% amino acid identity (residues P1, P3, P5 and P8) and bind with comparable efficacy to the murine MHC-encoded class I molecule H-2K b . However, these two peptides bind differently to H-2K bm8 , a natural H-2K b variant with a substitution in four amino acids on the floor of the peptide-binding site; HSV-8 binds with high and OVA-8 with a relatively low efficacy. To investigate which of the non-homologous peptide residues were responsible for this differential binding, we used substituted peptide variants and the class I thermodynamic stabilization assay. Variation at the solvent-exposed peptide residues P6 and P7 did not appreciably influence binding. By contrast, variation at the buried P2 and, surprisingly, at the solvent-exposed P4 residue was found to be important. Transplantation of the HSV-8 P2 or P4 residues onto the OVA-8 backbone created variant peptides O2S (P2I → S) and O4E (P4N → E) that bound considerably better to H-2K bm8 than OVA-8. Furthermore, the double-substituted peptide, O2S4E, bound even better, revealing a cooperative effect of the two residues. The reciprocally substituted peptides H2I and H4N, generated by grafting the OVA-8 P2 and P4 residues onto the HSV-8 backbone respectively, bound to H-2K bm8 slightly worse than HSV-8 but the doublesubstituted peptide H2I4N bound as poorly as OVA-8. Effects exerted by the P4 residue, which is solvent accessible and therefore available for the TCR contact, demonstrated that exposed peptide residues can, in certain situations, influence not only the TCR contact but also MHC‐peptide binding.

Many signals that cause apoptotic cell death operate by inducing transcription and translation of other (presumably death effector) mediators, and it is well established that stimulus-induced apoptosis can often be blocked by inhibiting transcription and translation. Transcriptional regulation of apoptosis, however, is incompletely understood. To gain insight into nuclear events associated with signal-induced apoptosis during T cell development, we studied signal-induced apoptosis of ex vivo isolated immature CD8(+)4(+) double-positive (DP) thymocytes. Stimuli utilizing the T cell receptor (TCR) signaling pathway or its parts (an alphaCD3/TCR monoclonal antibody, a Ca2+ ionophore, or a protein kinase C-activating phorbol ester) or a stimulus that antagonizes TCR signaling and apoptosis in T cell hybridoma (forskolin, a cyclic AMP-signaling activator) resulted in massive apoptosis of DP thymocytes. At the same time, these stimuli induced qualitatively similar but quantitatively unique patterns of inducible transcription factors (TFs) NF-kappaB/RelA-p50, AP-1 (Fos-Jun), and NUR-77. We focused our attention on the role of AP-1 (Fos-Jun) complex, which was strongly induced by all of the above stimuli and thus was a candidate for a proapoptotic TF. However, we found that AP-1/c-Fos induction was vital in prolonging DP thymocyte life, as judged by increased spontaneous and induced death of DP cells in Fos-/- mice. In direct support of this hypothesis, experiments with antisense oligonucleotides demonstrated that c-Fos plays an essential role in protecting normal DP thymocytes from Ca2+- and cAMP-induced apoptosis but not from TCR-mediated death. Together, these results demonstrate a physiological role for c-Fos in maintaining longevity of DP thymocytes.

We investigated the effector mechanisms operating during the rejection of a transplantable solid lymphoma E.G7 (H-2b) which expresses the gene encoding chicken ovalbumin (OVA). Anti-OVA cytotoxic T lymphocytes (CTL) completely and specifically protected animals from the onset of, but could not eradicate established, E.G7 tumors. The growth of the same lymphoma was also effectively prevented by the antibody GK1.5, whose target molecule, CD4, was expressed on E.G7 cells in vivo. Furthermore, GK1.5 was able to eradicate established solid E.G7 tumors. GK1.5-mediated tumor elimination was due to its antitumor activity, and not to the elimination of regulatory CD4+ cells, based on unimpaired tumor growth in the absence of GK1.5 in animals that genetically lack CD4 T cells. In vitro, GK1.5 did not kill tumor cells: complement activation or apoptosis induction were not evident. In vivo, GK1.5-mediated tumor regression did not depend on natural killer cells, but it absolutely required CD8+ cells and intact Fcgamma receptor. We conclude that, in the E.G7 model, the collaboration of antibody and CTL immunity was crucial for the successful immunotherapy of established tumors. The mechanism of this collaboration is discussed.

Fas-mediated apoptosis is a form of cell death that operates through a receptor-ligand interaction. The FasR has been implicated directly in peripheral T cell tolerance and activation-induced apoptosis of T cells in vitro, although to date its expression on murine peripheral T cells has been characterized incompletely. In this study, we document substantial expression of FasR on the vast majority of recent thymic emigrants and resting peripheral T lymphocytes. FasR ligation can induce death in a minor (approximately 5%) subset of these cells. By contrast to rather slow activation-mediated FasR up-regulation in vitro, we demonstrate that in vivo T cell activation by alpha CD3 mAb or superantigen results in rapid up-regulation of the FasR. This up-regulation is paralleled by the kinetics of activation-induced apoptosis in lymph node T cells. However, we demonstrate that the FasR is not necessary for activation-induced cell death. Lymph node T cells from young, healthy, FasR expression-deficient MRL-Ipr/Ipr and animals could be activated in vivo through the TCR-CD3 complex. Most importantly, MRL-Ipr/Ipr T cells underwent massive activation-induced apoptosis in response to high and intermediate doses of alpha CD3. At a low alpha CD3 dose, however, both MRL-Ipr/Ipr and MRL +/+ T cells were activated similarly, but only the latter underwent adequate apoptosis. Taken together, these findings suggest that in vivo, the Fas pathway may not be the only regulator of activation-induced T cell death, but that this pathway may be critical in regulating responses to weak stimuli.

The pathophysiological role of myocardial catecholamines in cardiomyopathies is still not completely understood. We there-fore assessed myocardial catecholamine concentrations (MCC) in 34 patients with hypertrophic cardiomyopathy (HCM) (76.5% males; mean age 46.7 +/- 11.6 years; left ventricular ejection fraction [LVEF] 75.3 +/- 9.8%) and in 32 patients with dilated cardiomyopathy (DCM) (87.5% males, mean age 43.1 +/- 12.5 years, LVEF 34.9 +/- 8.3%). Initial assessment included clinical work up, cardiac catheterization and endomyocardial biopsy. Myocardial norepinephrine (MNEC), epinephrine (MEC), and dopamine (MDC) concentrations in endomyocardial biopsy samples were measured using the catechol-O- methyl transferase radioenzymatic method. Significantly higher MNEC and MEC were demonstrated in HCM than in DCM patients (MNEC: 781.9 +/- 125.8 ng.g-1 fresh myocardial tissue (ft) HCM vs 262.6 +/- 68.9 ng.g-1 ft DCM, p0.01; and MEC: 91.6 +/- 13.9 ng.g-1 ft HCM vs 35.8 +/- 6.2 ng.g-1 ft DCM, P0.01). The difference in MDC did not reach statistical significance (76.1 +/- 8.3 ng.g-1 ft HCM vs 70.1 +/- 11.8 ng.g ft DCM; P0.05). In addition, we compared the MCC levels in 24 patients, clinically presented as dilated cardiomyopathy categorized according to the various aetiologies: 12/24 with primary DCM (75.0% males, mean age 49.6 +/- 9.5 years; LVEF 25.8 +/- 63%), 7/24 with alcohol-induced heart disease (85.7% males, mean age 46.8 +/- 7.1 years; LVEF 26.4 +/- 4.6%), and 5/24 with hypertensive heart disease (100% males, 45.1 +/- 10.6 years; LVEF 25.6 +/- 9.1%), but no significant difference was found among them (P0.05). There was no significant difference in tissue dopamine concentrations.

The Fas/APO-1 cytotoxic pathway plays an important role in the regulation of peripheral immunity. Recent evidence indicates that this regulatory function operates through deletion of activated T and B lymphocytes by CD4+ T cells expressing the Fas ligand. Because macrophages play a key role in peripheral immunity, we asked whether Fas was involved in T-cell-macrophage interactions. Two-color flow cytometry revealed that Fas receptor (FasR) was expressed on resting murine peritoneal macrophages. FasR expression was upregulated after activation of macrophages with cytokines or lipopolysaccharide, although only tumor necrosis factor-alpha rendered macrophages sensitive to anti-FasR antibody-mediated death. To determine the consequence of antigen presentation by macrophages to CD4+ T cells, macrophages were pulsed with antigen and then incubated with either Th1 or Th2 cell lines or clones. Th1, but not Th2, T cells induced lysis of 60-80% of normal macrophages, whereas macrophages obtained from mice with mutations in the FasR were totally resistant to Th1-mediated cytotoxicity. Macrophage cytotoxicity depended upon specific antigen recognition by T cells and was major histocompatibility complex restricted. These findings indicate that, in addition to deletion of activated lymphocytes, Fas plays an important role in deletion of activated macrophages after antigen presentation to Th1 CD4+ T cells. Failure to delete macrophages that constitutively present self-antigens may contribute to the expression of autoimmunity in mice deficient in FasR (lpr) or Fas ligand (gld).

The hypothesis that neuroendocrine response to military gunshot/missile (MG/M) wounds reflect the severity and type of wounds given by the Red Cross Wound Classification (RCWC), has been tested on 82 casualties of war in former Yugoslavia. Adrenaline (A), noradrenaline (N), Cortisol, triiodothyronine (T3), testosterone (TES) and prolactin (PRL) levels have been measured in blood samples taken on admission (2-18 hr after wounding) at Military Medical Academy. Neuroendocrine response to MG/M wounds has clearly reflected severity but not the type of wounds and it has been bidirectional, i.e. A, NA and cortisol levels positively related to, while T3 and TES levels were negatively related to severity of MG/M wounds. With regard to high compatibility between RCWC and Injury severity score (ISS) and the fact that magnitude of the neuroendocrine response is related to severity given by RCWC we have concluded that the RCWC is a good method of grading wound severity on the battlefield.

The participation of costimulatory molecule interactions in positive selection of T lymphocytes was addressed by assessing the ability of a positively selecting thymic epithelial cell (TEC) line, 427.1, to stimulate allospecific CTL responses. Stimulation of H-2s spleen cells with the H-2b expressing 427.1 line does not result in the generation of cells capable of lysing H-2b target cell lines. The level of expression of MHC class I molecules by 427.1 is lower than that found in other stimulatory TEC lines. However, this finding does not account for the nonstimulatory phenotype. Up-regulation of MHC class I did not result in stimulation, and fusion of 427.1 cells with stimulatory TEC resulted in a line with low MHC class I molecule expression and stimulatory phenotype. The TEC line 427.1 does not express the costimulatory molecule B7/BB1, and transfection of the B7/BB1-encoding DNA results in expression of the molecule and conversion into a stimulatory phenotype, demonstrating directly that the non-stimulatory phenotype is a result of lack of costimulation. However, B7/BB1 expression does not improve the ability of 427.1 TECs to induce positive selection. Intrathymic injection of the B7/BB1 transfected, compared with mock transfected 427.1 cells, rescued fewer CD8+ mature thymocytes in beta 2-microglobulin negative mice. Therefore, unlike the peripheral T cell responses to Ag, positive selection of T cells in the thymus may not depend on the costimulation provided by the presenting cell.

Fas is an apoptosis-related cell surface molecule whose defective transcription results in the lpr defect and autoimmunity. Recent analysis of Fas mRNA and protein expression in normal mice showed high expression in the thymus, on activated T cells, and on 5-10% of peripheral T cells. To investigate the role of Fas in the thymus, we analyzed its expression in fetal and adult thymocyte subsets. Fas was not expressed on fetal nor adult CD8-CD4- (double-negative, DN) T cell precursors. The earliest precursors that expressed low levels of FAS were the immediate precursors of DP thymocytes that bear the CD44-CD25-CD8loCD4loTCRlo phenotype. Other DN cells that expressed Fas appeared to be either non-T cells or mature alpha beta + DN thymocytes. The onset of Fas expression followed the onset of expression of CD8 and CD4 and Fas expression reached its peak in CD8+CD4+ double-positive (DP) thymocytes. Both single-positive (SP) subsets were largely Fas+ (CD8 SPCD4 SP) but expressed lower levels of Fas than DP cells. However, a majority (60%) of the most mature HSA(lo) SP cells (2-5% of all SP thymocytes) were Fas- and the remainder of the HSA(lo) SP cells was Fas(lo). We observed two main differences between Fas expression on fetal versus adult thymocytes. First, up to 90% of fetal gamma delta + DN cells expressed high levels of Fas, in contrast to the very low expression (7% Fas+ cells) among adult gamma delta + thymocytes. Second, whereas virtually all adult DP cells were Fas+, up to 75% of fetal day 16 DP cells were Fas-.(ABSTRACT TRUNCATED AT 250 WORDS)

During intrathymic negative selection by clonal deletion, crosslinking of the T cell receptor (TCR) induces cell death by delivering an apoptotic signal(s) to the nucleus along a calcium-dependent pathway. We investigated the reactivity of early precursor-containing thymocytes to Ca(2+)-induced signals, and discovered a breakpoint in their sensitivity to calcium-mediated cell death (CMCD). CD25+CD8-4- TCR- (triple negative [TN]) thymocytes stimulated with a calcium ionophore maintain their viability and precursor activity. By contrast, their immediate progeny, CD25-CD8lo4loTCR alpha beta lo (triple low [TL]) cells react to calcium elevation by abrogation of precursor activity and apoptotic cell death. This developmental difference is specific for CMCD, since both CD25+TN and CD25-TL cells are susceptible to steroid-induced apoptosis. The presence of bcl-2 mRNA correlates directly to the resistance to CMCD-CD25+ TN cells express it and CD25-TL cells do not. These experiments show that thymocytes become sensitive to Ca(2+)-induced apoptosis as soon as they begin to express molecules that mediate thymic selection, and suggest that a concomitant downregulation of bcl-2 may mediate this phenomenon.

Arginase (L-arginine-ureidohydrolase, EC 3.5.3.1) catalyses the hydrolysis of arginine to ornithine and urea. Its primary metabolic role is to remove the excess of ammonia through synthesis of urea. Ornithine, as a product of arginase reaction can be used for synthesis of polyamines.Rapid tissue growth after partial hepatectomy is accompanied by an increase in biosynthesis of polyamines. The aim of this study was to examine the importance of arginase in regenerating liver after partial hepatectomy and to investigate the influence of folic acid and methotrexate on arginase activity on this model of compensatory growth.It was established that arginase activity was significantly reduced in regenerating rat liver tissue at different time intervals after partial hepatectomy.Administration of folic acid to hepatectomised rats led to inhibition of arginase activity. Administration of methotrexate after hepatectomy increased the arginase activity.

Serum and CSF immunological findings were analysed in 37 patients with amyotrophic lateral sclerosis (ALS). ALS patients had significantly higher mean values of serum IgG and complement component C4 and significantly lower mean value of total haemolytic titre of complement (THC) compared with normal controls. Incidence of immune complexes (ICs) was significantly higher in sera of ALS patients than in normal controls. There was no significant difference regarding mean serum levels of IgM, IgA, and complement components C3 and Factor B between patients and controls. The blood-brain barrier (BBB) damage was found in 46% of patients. Intrathecal IgG synthesis was detected in six patients (16%). These results support the hypothesis of immune system involvement in ALS.

The fate of an immature thymocyte is determined by the specificity of its alpha beta T-cell receptor. Only cells expressing receptors that interact with sufficient affinity with major histocompatibility complex (MHC) molecules expressed on thymus epithelial cells are positively selected and go on to mature and seed the peripheral lymphoid organs. The H-2Kb class-I MHC molecule positively selects for the maturation of cytotoxic T lymphocytes that will respond in the periphery to H-2Kb cells presenting a foreign peptide. We have now analysed the ability of variant H-2Kb molecules to positively select T-cells that respond to H-2Kb with ovalbumin. Our results indicate that self-peptides, presented in the groove of the class-I molecule on thymus epithelial cells, are critically involved in positive selection of the T-cell repertoire. Furthermore, the ability of four different H-2Kb variants to select this response in the thymus correlates with their ability to present the ovalbumin peptide, indicating that a self-peptide mimic of the foreign peptide could be involved in positive selection.

By using indirect immunofluorescence method, we analyzed the presence of antinuclear, anticardiac, microsomal, parietal-cell, smooth-muscle and mitochondrial antibodies in sera of 33 patients with definite multiple sclerosis (MS), without clinical evidence of associated autoimmune disorder, and 14 patients with other neurological disorders (OND). In MS patients, the prevalence of both organ-specific and non-organ-specific antibodies was significantly higher (p less than 0.05) than in OND patients. In both groups, the titers of circulating antibodies were low. The presence of low levels of autoantibodies in sera of MS patients might be the result of immunodysregulation in MS.

This article briefly describes a method of evaluating the neutron spectra from measured pulse-height distribution produced by recoil protons in scintillation detector and an algorithm for shielding calculation in subgroup approximation by Monte Carlo method. Results of measurements and calculation of the fast neutron spectra at the external neutron converter at the RB reactor are presented.

SummaryIbuprofen in a dosage of 1200 mg. daily was shown in an open study of 247 patients to be effective in the treatment of rheumatoid arthritis, ankylosing spondylitis and non-articular rheumatism. Side-effects were minimal and particularly noteworthy was the absence of gastro-intestinal symptoms in 26 patients with known peptic ulceration who were treated with the drug.

SummarySixty-five patients with ankylosing spondylitis, all of whom were intolerant of or had failed to respond to previous therapy with phenylbutazone or indomethacin, were treated with 1200 mg. ibuprofen daily for at least 2 months. Clinical or subjective improvement was noted in 32 (49%), and the drug was well tolerated by all the patients, including 14 with gastro-intestinal disorders.

The effect of a mixture of l-DOPA and benserazide on the amount of dopamine in the corpus striatum of rats irradiated with 850 R of X-rays was investigated. The amount of dopamine in the corpus striatum was measured fluorimetrically at various times after irradiation. It was found that i.p. administration of l-DOPA and benserazide 1,2 and 5 days after irradiation produces significant replenishment of dopamine in the striatum, thus indicating that precursor uptake and metabolism, and probably amine storage, remained unaltered after irradiation.

On the basis of our first experiences with CO2 LASER in Otorhinolaryngology, we have observed as well as many other authors (1, 2, 3, 4, 5) that LASER enables very precise work, minimal traumatization of the tissue and rapid epithelization of the wound. We wished to apply these valiable advantages of LASER in pathology of the epipharynx which is unapproachable for a surgical knife.