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T-lymphocyte clones derived from populations sensitized to alloantigens in vitro were tested for their regulatory effects on pokeweed mitogen-stimulated immunoglobulin (Ig) secretion. Clones with natural killer (NK)-like cytotoxicity and/or suppressive activity for lymphoproliferative (LP) responses potently inhibited Ig secretion. Moreover, certain alloproliferative T4 + interleukin-2 (IL-2)-secreting 'helper' clones shared this strong suppressive activity on Ig secretion. The remaining clones enhanced, rather than suppressed, Ig production. Inhibition by all types of suppressive clones appeared not to be restricted by MHC products, since allogeneic HLA-mismatched donors were suppressed as efficiently as the autologous donor. Suppression was radio resistant, and was apparently not caused by absorption of IL-2, or cytotoxicity of the clones. Suppression was still detectable at plateau levels when cloned cells were added as late as 96 hr after the initiation of the cultures, suggesting an inhibitory mechanism divorced from early B-cell activation events. Thus, T-lymphocyte clones with distinct different functional activities share similar profound suppressive effects on Ig secretion in vitro. [ABSTRACT FROM AUTHOR]

Arginine phosphorylation plays numerous roles throughout biology. Arginine kinase (AK) catalyzes the delivery of an anionic phosphoryl group (PO 3 - ) from ATP to a planar, trigonal nitrogen in a guanidinium cation. Density functional theory (DFT) calculations have yielded a model of the transition state (TS) for the AK-catalyzed reaction. They reveal a network of over 50 hydrogen bonds that delivers unprecedented pyramidalization and out-of-plane polarization of the arginine guanidinium nitrogen (Nη2) and aligns the electron density on Nη2 with the scissile P-O bond, leading to in-line phosphoryl transfer via an associative mechanism. In the reverse reaction, the hydrogen-bonding network enforces the conformational distortion of a bound phosphoarginine substrate to increase the basicity of Nη2. This enables Nη2 protonation, which triggers PO 3 - migration to generate ATP. This polarization-pyramidalization of nitrogen in the arginine side chain is likely a general phenomenon that is exploited by many classes of enzymes mediating the post-translational modification of arginine., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The interaction energies of two series of molecular balances (1-X with X = H, Me, OMe, NMe 2 and 2-Y with Y = H, CN, NO 2 , OMe, NMe 2 ) designed to probe carbonyl…carbonyl interactions were analysed at the B3LYP/6-311++G(d,p)-D3 level of theory using the energy partitioning method of Interacting Quantum Atoms/Fragments (IQA/IQF). The partitioned energies are analysed by the Relative Energy Gradient (REG) method, which calculates the correlation between these energies and the total energy of a system, thereby explaining the role atoms have in the energetic behaviour of the total system. The traditional "back-of-the-envelope" open and closed conformations of molecular balances do not correspond to those of the lowest energy. Hence, more care needs to be taken when considering which geometries to use for comparison with the experiment. The REG-IQA method shows that the 1-H and 1-OMe balances behave differently to the 1-Me and 1-NMe 2 balances because the latter show more prominent electrostatics between carbonyl groups and undergoes a larger dihedral rotation due to the bulkiness of the functional groups. For the 2-Y balance, REG-IQA shows the same behaviour across the series as the 1-H and 1-OMe balances. From an atomistic point of view, the formation of the closed conformer is favoured by polarisation and charge-transfer effects on the amide bond across all balances and is counterbalanced by a de-pyramidalisation of the amide nitrogen. Moreover, focusing on the oxygen of the amide carbonyl and the α-carbon of the remaining carbonyl group, electrostatics have a major role in the formation of the closed conformer, which goes against the well-known n-π* interaction orbital overlap concept. However, REG-IQF shows that exchange-correlation energies overtake electrostatics for all the 2-Y balances when working with fragments around the carbonyl groups, while they act on par with electrostatics for the 1-OMe and 1-NMe 2 . REG-IQF also shows that exchange-correlation energies in the 2-Y balance are correlated to the inductive electron-donating and -withdrawing trends on aromatic groups. We demonstrate that methods such as REG-IQA/IQF can help with the fine-tuning of molecular balances prior to the experiment and that the energies that govern the probed interactions are highly dependent on the atoms and functional groups involved.

Novel building blocks are in constant demand during the search for innovative bioactive small molecule therapeutics by enabling the construction of structure-activity-property-toxicology relationships. Complex chiral molecules containing multiple stereocenters are an important component in compound library expansion but can be difficult to access by traditional organic synthesis. Herein, we report a biocatalytic process to access a specific diastereomer of a chiral amine building block used in drug discovery. A reductive aminase (RedAm) was engineered following a structure-guided mutagenesis strategy to produce the desired isomer. The engineered RedAm (IR-09 W204R) was able to generate the ( S , S , S )-isomer 3 in 45% conversion and 95% ee from the racemic ketone 2 . Subsequent palladium-catalyzed deallylation of 3 yielded the target primary amine 4 in a 73% yield. This engineered biocatalyst was used at preparative scale and represents a potential starting point for further engineering and process development.

The interaction energies of nine XH···π (X = C, N, and O) benzene-containing van der Waals complexes were analyzed, at the atomic and fragment levels, using QTAIM multipolar electrostatics and the energy partitioning method interacting quantum atoms/fragment (IQA/IQF). These descriptors were paired with the relative energy gradient method, which solidifies the connection between quantum mechanical properties and chemical interpretation. This combination provides a precise understanding, both qualitative and quantitative, of the nature of these interactions, which are ubiquitous in biochemical systems. The formation of the OH···π and NH···π systems is electrostatically driven, with the Q zz component of the quadrupole moment of the benzene carbons interacting with the charges of X and H in XH. There is the unexpectedly intramonomeric role of X-H (X = O, N) where its electrostatic energy helps the formation of the complex and its covalent energy thwarts it. However, the CH···π interaction is governed by exchange-correlation energies, thereby establishing a covalent character, as opposed to the literature's designation as a noncovalent interaction. Moreover, dispersion energy is relevant, statically and in absolute terms, but less relevant compared to other energy components in terms of the formation of the complex. Multipolar electrostatics are similar across all systems., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The relative energy gradient (REG) method is paired with the topological energy partitioning method interacting quantum atoms (IQA), as REG-IQA, to provide detailed and unbiased knowledge on the intra- and interatomic interactions. REG operates on a sequence of geometries representing a dynamical change of a system. Its recent application to peptide hydrolysis of the human immunodeficiency virus-1 (HIV-1) protease (PDB code: 4HVP) has demonstrated its full potential in recovering reaction mechanisms and through-space electrostatic and exchange-correlation effects, making it a compelling tool for analyzing enzymatic reactions. In this study, the computational efficiency of the REG-IQA method for the 133-atom HIV-1 protease quantum mechanical system is analyzed in every detail and substantially improved by means of three different approaches. The first approach of smaller integration grids for IQA integrations reduces the computational overhead by about a factor of 3. The second approach uses the line-simplification Ramer-Douglas-Peucker (RDP) algorithm, which outputs the minimal number of geometries necessary for the REG-IQA analysis for a predetermined root mean squared error (RMSE) tolerance. This cuts the computational time of the whole REG analysis by a factor of 2 if an RMSE of 0.5 kJ/mol is considered. The third approach consists of a "biased" or "unbiased" selection of a specific subset of atoms of the whole initial quantum mechanical model wave-function, which results in more than a 10-fold speed-up per geometry for the IQA calculation, without deterioration of the outcome of the REG-IQA analysis. Finally, to show the capability of these approaches, the findings gathered from the HIV-1 protease system are also applied to a different system named haloalcohol dehalogenase (HheC). In summary, this study takes the REG-IQA method to a computationally feasible and highly accurate level, making it viable for the analysis of a multitude of enzymatic systems.

A combined Bonding Evolution Theory (BET) and Interacting Quantum Atoms-Relative Energy Gradient (IQA-REG) study is carried out on a non-polar zw-type [3+2] cycloaddition (32CA) reaction. BET is the joint use of Catastrophe Theory and the topology of the Electron Localization Function (ELF) to characterise molecular mechanisms, while IQA is a quantum topological energy partitioning method and REG is a method to compute chemical insight at atomistic level, usually in connection with energy. This 32CA reaction involves the simplest nitrone with ethylene and has been studied here at B3LYP/6-311G(d,p) level within the context of Molecular Electron Density Theory (MEDT), which is based on the idea that changes in electron density, and not molecular orbital interactions, are responsible for chemical reactivity. We aim to determine the origin of the high activation energy of 32CA reactions involving zwitterionic three-atom-components. The BET study and IQA-REG method are applied to the overall activation energy path. While BET suggests that the barrier is mainly associated with the rupture of the nitrone CN double bond, IQA-REG indicates that it is mainly related to the rupture of the ethylene CC double bond. The present study shows that activation energies can be accurately and easily described by IQA-REG, and its complementary use with BET helps achieving a more detailed description of molecular mechanisms.

Foot fractures are common injuries. This retrospective study evaluates their frequency, incidence, treatment and outcomes with emphasis on complex trauma of the foot (CTF), an injury that affects soft tissue as well as bone. From 2005 to 2015, 506 patients with foot fractures were treated at our institution; of these, 27 had CTF. The Zwipp score was applied to diagnose CTF, the Gustilo-Anderson classification to grade open fractures and the Tscherne classification to grade closed fractures. Twelve months after the trauma, 20 CTF patients underwent the final X-ray assessment and clinical evaluation with the Visual Analogue Scale Foot and Ankle (VASFA), the Foot Function Index (FFI) and the 12-Item Short Form Survey (SF-12). Data were analyzed with the Spearman rank correlation test. The forefoot was the most frequently involved compartment both in patients with foot fracture and in those with CTF. At 12-month follow-up, the CTF patients showed a VASFA score of 51.5, an FFI of 47.5 and SF-12 scores of 37.9 (physical component summary) and 45.2 (mental component summary). The VASFA score and the FFI showed a significant correlation (rs = 0.84; p = 0.001). CTF is the cause of considerable residual disability and deeply affects quality of life., (© 2021. Springer-Verlag France SAS, part of Springer Nature.)

Partition coefficients quantify a molecule's distribution between two immiscible liquid phases. While there are many methods to compute them, there is not yet a method based on the free energy of each system in terms of energy and entropy, where entropy depends on the probability distribution of all quantum states of the system. Here we test a method in this class called Energy Entropy Multiscale Cell Correlation (EE-MCC) for the calculation of octanol-water logP values for 22 N-acyl sulfonamides in the SAMPL7 Physical Properties Challenge (Statistical Assessment of the Modelling of Proteins and Ligands). EE-MCC logP values have a mean error of 1.8 logP units versus experiment and a standard error of the mean of 1.0 logP units for three separate calculations. These errors are primarily due to getting sufficiently converged energies to give accurate differences of large numbers, particularly for the large-molecule solvent octanol. However, this is also an issue for entropy, and approximations in the force field and MCC theory also contribute to the error. Unique to MCC is that it explains the entropy contributions over all the degrees of freedom of all molecules in the system. A gain in orientational entropy of water is the main favourable entropic contribution, supported by small gains in solute vibrational and orientational entropy but offset by unfavourable changes in the orientational entropy of octanol, the vibrational entropy of both solvents, and the positional and conformational entropy of the solute., (© 2021. The Author(s).)

Amino acid hydroxylases depend directly on the cellular TCA cycle via their cosubstrate α-ketoglutarate (α-KG) and are highly useful for the selective biocatalytic oxyfunctionalization of amino acids. This study evaluates TCA cycle engineering strategies to force and increase α-KG flux through proline-4-hydroxylase (P4H). The genes sucA (α-KG dehydrogenase E1 subunit) and sucC (succinyl-CoA synthetase β subunit) were alternately deleted together with aceA (isocitrate lyase) in proline degradation-deficient Escherichia coli strains (ΔputA) expressing the p4h gene. Whereas, the ΔsucCΔaceAΔputA strain grew in minimal medium in the absence of P4H, relying on the activity of fumarate reductase, growth of the ΔsucAΔaceAΔputA strictly depended on P4H activity, thus coupling growth to proline hydroxylation. P4H restored growth, even when proline was not externally added. However, the reduced succinyl-CoA pool caused a 27% decrease of the average cell size compared to the wildtype strain. Medium supplementation partially restored the morphology and, in some cases, enhanced proline hydroxylation activity. The specific proline hydroxylation rate doubled when putP, encoding the Na + /l-proline transporter, was overexpressed in the ΔsucAΔaceAΔputA strain. This is in contrast to wildtype and ΔputA single-knock out strains, in which α-KG availability obviously limited proline hydroxylation. Such α-KG limitation was relieved in the ΔsucAΔaceAΔputA strain. Furthermore, the ΔsucAΔaceAΔputA strain was used to demonstrate an agar plate-based method for the identification and selection of active α-KG dependent hydroxylases. This together with the possibility to waive selection pressure and overcome α-KG limitation in respective hydroxylation processes based on living cells emphasizes the potential of TCA cycle engineering for the productive application of α-KG dependent hydroxylases. Biotechnol. Bioeng. 2017;114: 1511-1520. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Background: Sucralose is an organochlorine artificial sweetener approximately 600 times sweeter than sucrose and used in over 4,500 products. Long-term carcinogenicity bioassays on rats and mice conducted on behalf of the manufacturer have failed to show the evidence of carcinogenic effects., Objective: The aim of this study was to evaluate the carcinogenic effect of sucralose in mice, using a sensitive experimental design., Methods: Five groups of male (total n = 457) and five groups female (total n = 396) Swiss mice were treated from 12 days of gestation through the lifespan with sucralose in their feed at concentrations of 0, 500, 2,000, 8,000, and 16,000 ppm., Results: We found a significant dose-related increased incidence of males bearing malignant tumors (p < 0.05) and a significant dose-related increased incidence (p < 0.01) of hematopoietic neoplasias in males, in particular at the dose levels of 2,000 ppm (p < 0.01) and 16,000 ppm (p < 0.01)., Conclusions: These findings do not support previous data that sucralose is biologically inert. More studies are necessary to show the safety of sucralose, including new and more adequate carcinogenic bioassay on rats. Considering that millions of people are likely exposed, follow-up studies are urgent.

The efficient coupling of biotransformation steps to an existing fermentation pathway is an interesting strategy to expand the product portfolio of Corynebacterium glutamicum as whole-cell biocatalyst. This is especially challenging if the biotransformation step comprises a direct link to central metabolism, as in the case of α-ketoglutarate-dependent oxygenase catalysis. Aiming at trans-4-hydroxy-L-proline (Hyp) production from glucose in a minimal medium, the proline-4-hydroxylase gene from Dactylosporangium sp. strain RH1 was introduced into a proline-producing, isoleucine-bradytroph C. glutamicum strain. The production of proline was found to be induced by isoleucine limitation. Proline and Hyp production were found to depend differently on isoleucine limitation. Severe isoleucine limitation was shown to result in proline accumulation and low hydroxylation rates both in batch and continuous cultivation set-ups. The investigation of different steady states with various glucose/isoleucine molar ratios revealed that optimal conditions for Hyp production are met around a molar ratio of 46:1, where isoleucine limitation is sufficient to trigger proline production but the hydroxylation rate is high enough to convert the majority of formed proline to Hyp. A high cell-density fed-batch set-up was designed, capable of producing 7.1 g L(-1) of Hyp from glucose in 23 h with 98.5% conversion of proline to Hyp. Reaction engineering, specifically the fine-tuning of the glucose/isoleucine concentration ratio, enabled control of the fermentation profile and thus the accumulation of the desired product Hyp from glucose in minimal and defined media., (© 2014 Wiley Periodicals, Inc.)

In recent years, there has been increasing evidence of the potential pathogenic significance of equine gammaherpesviruses in the horse. In humans, cattle and mice, gammaherpesviruses have already been associated with uterine infection. The aim of the present study was to investigate the presence of gammaherpesviruses in uterine flushings of mares with reproductive problems and to evaluate if there was a possible statistical association with clinical and laboratory findings in these cases. A total of 80 uterine flushings were collected from 61 mares with different reproductive problems and these were tested for equine herpesviruses (EHV) 1-5 by PCR. In the case of each mare in the study, the age, history of infertility, presence of anatomical defects in the reproductive tract, presence of systemic or local disease at time of sampling, phase in the oestrous cycle, post-partum interval, nature of uterine lavage performed (low versus large volume lavage), cytological and bacteriological examination results from the uterine flushing, and PCR herpesvirus results were recorded. Univariate analysis and multivariable logistic regression models were used to identify possible statistical associations and risk factors. Nine out of 61 mares (14.7%) had EHV-5 DNA in their uterine flushings. Co-infections with EHV-1 and EHV-2 were present in two cases. Of all the variables analyzed, only the cytological examination findings were associated with EHV-5 PCR positive results, both on univariate and multivariable analysis, especially in cases with an inflammation score of 3. It is postulated that presence of EHV-5 infection in the non-pregnant uterus may have a role to play in reproductive dysfunction and have a negative consequence on the pregnant uterus. Additional studies involving both healthy mares and mares with reproductive problems need to be performed, however, to elucidate whatever role equine gammaherpesviruses may play in the reproductive tract. This would be very worthwhile, since reproductive problems can have a significant impact on the equine breeding industry. Gaining a greater understanding of its causes could lead to new approaches for prevention and treatment., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Benzimidazole and indane are the two key fragments in our potent and selective MCH-1 receptor (MCHR1) antagonists. To identify novel linkers connecting the two fragments, we investigated diamino-cycloalkane-derived analogs and discovered highly potent antagonists with cis-1,4-diaminocyclohexane as a unique spacer in this chemical class. Structural overlay suggested that cis-1-substituted-4-aminocyclohexane functions as a bioisostere of 4-substituted-piperidine and that the active conformation adopts a U-shaped orientation., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Microbial physiology plays a crucial role in whole-cell biotransformation, especially for redox reactions that depend on carbon and energy metabolism. In this study, regio- and enantio-selective proline hydroxylation with recombinant Escherichia coli expressing proline-4-hydroxylase (P4H) was investigated with respect to its interconnectivity to microbial physiology and metabolism. P4H production was found to depend on extracellular proline availability and on codon usage. Medium supplementation with proline did not alter p4h mRNA levels, indicating that P4H production depends on the availability of charged prolyl-tRNAs. Increasing the intracellular levels of soluble P4H did not result in an increase in resting cell activities above a certain threshold (depending on growth and assay temperature). Activities up to 5-fold higher were reached with permeabilized cells, confirming that host physiology and not the intracellular level of active P4H determines the achievable whole-cell proline hydroxylation activity. Metabolic flux analysis revealed that tricarboxylic acid cycle fluxes in growing biocatalytically active cells were significantly higher than proline hydroxylation rates. Remarkably, a catalysis-induced reduction of substrate uptake was observed, which correlated with reduced transcription of putA and putP, encoding proline dehydrogenase and the major proline transporter, respectively. These results provide evidence for a strong interference of catalytic activity with the regulation of proline uptake and metabolism. In terms of whole-cell biocatalyst efficiency, proline uptake and competition of P4H with proline catabolism are considered the most critical factors.

The activity of proteases chymotrypsin and subtilisin dissolved in a range of protic hydroxylalkylammonium ionic liquids was tested against the model substrate APEE (N-acetyl-L-phenylalanine ethyl ester); activity was only observed for subtilisin in diethanolammonium chloride (DEA Cl), while chymotrypsin was not active in any PIL tested.

This paper describes the lead optimization of a new series of potent, selective, orally bioavailable, brain-penetrant MCH-1 receptor antagonists. A major focus of the work was to achieve a selectivity profile appropriate for in vivo efficacy studies and safety.

A novel series of orally active pyrimido[5,4-3][1,2,4]triazine-5,7-diamine-based hypoglycemic agents have been identified. These compounds show non-selective inhibitory properties against a panel of protein tyrosine phosphatases including PTP1B. Compounds 12 and 13 display oral glucose lowering effects in ob/ob mice.

Molecular features of ligand binding to MHC class II HLA-DR molecules have been elucidated through a combination of peptide structure-activity studies and structure-based drug design, resulting in analogues with nanomolar affinity in binding assays. Stabilization of lead compounds against cathepsin B cleavage by N-methylation of noncritical backbone NH groups or by dipeptide mimetic substitutions has generated analogues that compete effectively against protein antigens in cellular assays, resulting in inhibition of T-cell proliferation. Crystal structures of four ternary complexes of different peptide mimetics with the rheumatoid arthritis-linked MHC DRB10401 and the bacterial superantigen SEB have been obtained. Peptide-sugar hybrids have also been identified using a structure-based design approach in which the sugar residue replaces a dipeptide. These studies illustrate the complementary roles played by phage display library methods, peptide analogue SAR, peptide mimetics substitutions, and structure-based drug design in the discovery of inhibitors of antigen presentation by MHC class II HLA-DR molecules.

We have identified a heptapeptide with high affinity to rheumatoid arthritis-associated class II major histocompatibility (MHC) molecules. Using a model of its interaction with the class II binding site, a variety of mimetic substitutions were introduced into the peptide. Several unnatural amino acids and dipeptide mimetics were found to be appropriate substituents and could be combined into compounds with binding affinities comparable to that of the original peptide. Compounds were designed that were several hundred-fold to more than a thousand-fold more potent than the original peptide in inhibiting T-cell responses to processed protein antigens presented by the target MHC molecules. Peptidomimetic compounds of this type could find therapeutic use as MHC-selective antagonists of antigen presentation in the treatment of autoimmune diseases.

Peptides binding to a particular class II major histocompatibility complex (MHC) molecule can inhibit the activation of T cells by other peptides binding to the same molecule, a phenomenon termed class II MHC blockade. All class II-binding peptides exert MHC blockade in vivo in depot form with adjuvant, and some also retain their blocking properties in soluble form. We demonstrate here that soluble peptides, when used at doses causing short-term MHC blockade, can also induce long-term antigen-specific T cell tolerance to themselves. The tolerogenicity of soluble peptides correlates with their antigenicity in adjuvant, but it is not necessarily related to their capacity to act as class II blockers in vivo. The tolerant state is manifested in a decreased production of both T helper cell 1 (Th1)-type and Th2-type lymphokines, and it cannot be reversed by interleukin-2. Once T cells are primed with a peptide in complete Freund's adjuvant, they are resistant to tolerization with the same peptide applied in soluble form. Tolerance induction is partially impaired in B cell-deficient mu MT-/- mice, suggesting a role for B cell antigen presentation in this process. The results suggest that the potential immunogenicity of class II MHC blockers could be circumvented by choosing a tolerogenic mode of application.

Certain HLA class II-specific monoclonal antibodies (mAb) cause up to 90% decrease in the cell surface expression of class II molecules. This down-regulation is isotype-specific, i.e. DR-specific mAb do not affect the expression of DP and DQ molecules. However, antibodies binding to one DR allotype down-regulate both allotypes in heterozygous antigen-presenting cells (APC), indicating that the phenomenon is not a direct consequence of ligation. All down-regulating mAb identified recognize the first (peptide binding) domains of class II heterodimers, and strongly inhibit the activation of class II-restricted human T cells in vitro. Conversely, non-down-regulating mAb fail to inhibit T cell activation, and most of them (four out of five) recognize class II second domains. Down-regulating antibodies are cytotoxic for B lymphoblastoid cell lines and for a small proportion of normal activated B cells. Their F(ab')2 fragments mediate both down-regulation and cytotoxicity, whereas the monovalent Fab fragments are not cytotoxic, but retain the down-regulatory and T cell inhibitory properties. These findings raise the possibility of a class II major histocompatibility complex-specific, antibody-based immunosuppressive therapy without cytotoxic side effects.

The recognition of antigenic peptides by CD4+ helper T cells is demonstrated here to result in a dramatic (up to 90%) decrease in expression of major histocompatibility complex (MHC) class II molecules on the surface of antigen-presenting cells (APC). The reduction is selective to the class II isotype presenting the antigen, but if affects both allelic forms of the same isotype in heterozygous APC. The observed MHC down-regulation requires a specific T cell receptor-peptide-class II interaction, a direct contact between T cell and APC, and the involvement of CD2 molecules. These findings have important implications for the regulation of immune response, self tolerance, and autoimmunity.

After illustrating the new set of rules in matter of stupefacient and psychotropic drugs, introduced in Italy on December 1975, and the duties assigned by the law to the judicial power, the findings are set forth here of an investigation carried out on 40 youths whose addiction to the use of drugs had been reported to the juvenile court of Rome up to April 30, 1977. Anamnestic, social, judicial and clinical data on such subjects were obtained. Even with the obvious reservations resulting from the extremely small sample, some findings are observed that appear to be significant: a considerable portion of the minors addicted to the use of drugs was the recipient of other interventions by the juvenile court in the civil, administrative and criminal sphere; for the males, the prevailing anamnestetic and social data correspond to the characteristics of the other subjects, with whom the court usually deals at the "re-educational" or criminal level, while, with regard to females, the picture is remarkably different. The use of heroin seems to be wide-spread among the males, where also prevail previous hospitalizations caused by the use of drugs. The Authors advocate a new and more extensive verification, to be carried out after a period of time.

The influence of Cianidanol (Ci), a cytoprotective radical scavenger, on peripheral blood mononuclear cells (PBMC) was assessed with respect to its immunomodulatory function. In previous studies performed in our laboratory, a bidirectional influence of Ci on the immune response was observed, depending on its concentration. In order to elucidate this effect, the influence of Ci on macrophage (M phi) and B-cell function was investigated. A marked dose-dependent suppression of M phi phagocytosis by Ci could be detected. Furthermore, PGE2 synthesis of non-activated and PHA-activated PBMC was inhibited in the presence of Ci. This effect was shown to be due to an inhibition of M phi cyclooxygenase. It was also demonstrated that neither spontaneous nor Staphylococcus aureus Cowan I induced proliferation of highly purified B-cells was enhanced by Ci. Similar results were obtained by measuring the influence of Ci on immunoglobulin secretion of purified B-cells, exposed to Klebsiella membrane preparations. From these data it can be concluded that the previously described enhancing effect of Ci on immunoglobulin secretion is probably T-cell mediated.