In silico prediction of the interaction of legacy and novel per- and poly-fluoroalkyl substances (PFAS) with selected human transporters and of their possible accumulation in the human body.

Per- and poly-fluorinated compounds constitute a wide group of fluorocarbon chemicals with widespread industrial applications, ranging from non-stick coating in cookware to water surfactants, from fire-fighting foams to water-repellent coatings on textiles. Presently, over 12,000 PFAS are known worldwide. In recent years, extensive research has focused on investigating the biological effects of these molecules on various organisms, including humans. Here, we conducted in silico simulations to examine the potential binding of a representative selection of PFAS to various human proteins known to be involved in chemical transportation and accumulation processes. Specifically, we targeted human serum albumin (HSA), transthyretin (TTR), thyroxine binding protein (TBG), fatty acid binding proteins (FABPs), organic anion transporters (OATs), aiming to assess the potential for bioaccumulation. Molecular docking simulations were employed for this purpose, supplemented by molecular dynamics (MD) simulations to account for protein flexibility, when necessary. Our findings indicate that so-called "legacy PFAS" such as PFOA or PFOS exhibit a higher propensity for interaction with the analysed human protein targets compared to newly formulated PFAS, characterised by higher branching and hydrophilicity, and possibly a higher accumulation in the human body.

A novel SWCNT platform bearing DOTA and ß-cyclodextrin units. "One shot" multidecoration under microwave irradiation.

The functionalization of single-walled carbon nanotubes (SWCNTs) via microwave-assisted grafting reactions enables efficient multidecoration in a single step. A novel water-soluble SWCNT platform was prepared via the simple 1,3-dipolar cycloaddition of azomethine ylides under dielectric heating. Thanks to a single grafting reaction the CNT surface binds in a 1 : 1 ratio an amino acidic ß-cyclodextrin (ß-CD) derivative and the DOTAMA moiety (1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid monoamide). This novel "one shot" synthesis, compared with multistep functionalizations, preserves the SWCNT's structural integrity (TEM images). Besides thermogravimetric analyses, the determination of the amount of ß-CD and DOTA moieties grafting onto the SWCNT's surface was performed on the basis of phenolphthalein and gadolinium complexation, respectively.

Cold-induced alteration in the global structure of the male sex chromosome of In1BM2(reinverted) of Drosophila melanogaster is associated with increased acetylation of histone 4 at lysine 16.

In Drosophila melanogaster, dosage compensation occurs through hypertranscription of sex-linked genes in males. The hypertranscription involves acetylation of histone 4 at lysine 16 (H4K16) on amale X-chromosome, brought about by a histone acetyltransferase encoded by the dosage compensation gene, males absent on the first (mof). We report a phenomenon in the strain In(1)B(M2)(reinverted) of D. melanogaster where the global structure of the male X-chromosome can be altered at the third instar larval stage through a 4-h cold shock at 12+/-1 degrees C. We show that the cold shock results in a transient hyperacetylation of H4K16 and an increased expression of MOF. Control proteins H4 acetylated at lysine 5, and the dosage compensation gene msl-2, do not show any change in expression after cold shock. Cytology of the male X-chromosome at different time points during cold shock and recovery, suggests that the hyperacetylation of H4 at lysine 16 causes the X-chromosome to corkscrew into itself, thereby achieving the cold-induced change in the higher order structure of the male polytene X-chromosome. Our studies suggest a role for H4K16 in maintaining the structure of the male X-chromosome in Drosophila.

Erythrocytes in human transplantation: effects of pretreatment with ABO group-specific antigens.

Erythrocyte group antigens A and B can act as potent and group-specific transplantation antigens in man. ABO group-incompatible recipients pretreated with such antigens have rejected skin allografts obtained from donors incompatible for the same antigens in an accelerated (4-5 days) or white graft manner. Skin grafts applied to the same recipients from ABO-compatible donors were accorded first-set survival times. Intact erythrocyte suspensions and antigens isolated from hog (A substance) and horse (B substance) stomachs, were equally capable of inducing this type of allograft sensitivity. The latter observation broadens the spectrum of heterologous antigens capable of inducing allograft sensitivity in the mammalian host and provides a readily available, heat-stable, and water-soluble source of antigens for further studies of allograft rejection mechanisms in man.

Role of Ia-like products of the main histocompatibility complex in conditioning skin allograft survival in man.

This report correlates the survival time of 93 intrafamilial skin allografts performed under conditions of main histocompatibility complex (HLA) haploidentity with donor-recipient compatibility for products of the HLA-A, -B, -C, and -DR, as well as C3 proactivator, Glyoxalase I, and P loci located on the human 6th chromosome. Incompatibilities for HLA-A and -B (and to a lesser extent for HLA-C) and(or) for HLA-DR products exerted a strong influence upon the fate of skin allografts. When HLA-A and -B were considered alone, the most compatible group of grafts had a mean survival time of 15.8 d, as compared with 11.3 d for the most incompatible transplants. HLA-DR compatibility alone was associated with a mean survival time of 15.3 d, whereas HLA-DR-incompatible grafts had a mean survival time of 11.5 d. Incompatibilities for C3 proactivator, Glyoxalase I, and P did not have a significant effect upon graft survival. There was no evidence of an association between donor-recipient incompatibility at HLA-A, -B, or -C or at HLA-DR; such incompatibilities occurred independently of each other, in spite of the state of linkage disequilibrium known to exist between HLA-B and -DR. Incompatibilities for HLA-A, -B, and for HLA-DR exerted a potent additive effect upon graft survival. Skin grafts bearing one, two, or three incompatibilities had a mean survival time of 16.2, 13.7, and 10.7 d, respectively (P <0.0005).The results point to the important role played by the Ia-like products of the HLA complex (HLA-DR) in conditioning skin allograft survival in man. This consideration may be of direct relevance to the potential clinical usefulness of in vitro serological techniques for the detection of donor-recipient compatibility for HLA-DR.

Structure of adenovirus fibre. II. Morphology of single fibres.

Adenovirus type 2 fibres in crystals appear to be significantly longer than found previously (accompanying paper). We therefore examined isolated fibre by electron microscopy and measured a length of 370 A, consistent with the length found in the crystals. The specific N-terminal structure of the fibre caused a heterogeneity in the length that may at least partially explain the values of 280 to 310 A published previously. Green et al. described a 15 amino acid repeat in the primary structure of the shaft of the fibre thought to be associated with the specific three-dimensional folding of the shaft. We compared the adenovirus type 2 (with 22 repeats) and type 3 (with 6 repeats) fibre lengths and derived a contribution of 13.2 A to the length of the shaft per 15 amino acid repeat. Specific morphological features of the fibre are discussed in relation to its amino acid sequence.

Conformational flexibility and polymerization of vesicular stomatitis virus matrix protein.

The matrix protein of vesicular stomatitis virus (VSV) plays a pivotal role in viral assembly. We previously demonstrated the ability of M protein to self-associate at low salt concentrations. Now, we show the ability of M protein to polymerize in the presence of ZnCl2 in a nucleation-dependent manner. Analysis of kinetics revealed that the nuclei are probably made of three or four molecules of M. These results are consistent with the idea that in vitro self association of M protein is not due to amorphous aggregation but rather reflects an intrinsic ability of M to polymerize. Using attenuated total reflectance Fourier transform infrared spectroscopy, we showed that M polymerization is associated with an increase in the beta-sheet content of the protein. We propose a model explaining both the apparent M protein solubility in infected cells and how M polymerization could promote viral assembly. Data available for other negative strand viruses suggest that M polymerization may be the general basis of viral assembly.

Human adenovirus serotype 3 (Ad3) and the Ad3 fiber protein bind to a 130-kDa membrane protein on HeLa cells.

The fiber protein of adenovirus mediates the interaction of adenovirus with cell membrane receptors. We have produced the Ad3 fiber protein in the baculovirus expression system. Biochemical, morphological and functional analyses showed that the recombinant fiber was properly folded and functionally competent. The specific binding of Ad3 virus to two HeLa membrane proteins of 130 and 100 kDa was demonstrated with an overlay protein binding assay. In the same assay, Ad3 fiber only recognized the 130-kDa protein. Divalent cations seemed to be important for the interaction of both virus and fiber with these proteins.

Targeting cells with MR imaging probes based on paramagnetic Gd(III) chelates.

The low sensitivity is the major disadvantage of MRI as compared to PET. Therefore, amplification strategies are necessary for specific pathway labeling. This survey is aimed at exploring different routes to the entrapment of Gd(III) chelates in various type of cells at amounts sufficiently large to allow MRI visualization. Namely, the obtained results have been summarized in terms of internalization via i) pinocytosis; ii) phagocytosis; iii) receptors; iv) receptor mediated endocytosis; v) transporters; vi) transmembrane carrier peptides. MRI visualization of cells appears possible when the number of internalized Gd(III) chelates is of the order of 10(7)-10(8)/cell. Pinocytosis shows to be particularly useful for labeling cells that can be incubated for several hours in the presence of high concentrations of Gd-agent. This approach appears very effective for labeling stem cells. Nanoparticles filled with Gd-chelates can be used for an efficient loading of cells endowed with a good phagocytic activity. Entrapment via receptors most often results in receptor mediated endocytosis. Suitably functionalized monomeric and multimeric Gd-chelates can be considered for being internalized by this route as well as supramolecular systems such as those formed between Avidin and biotinylated Gd-complexes. Exploitation of up-regulated transporters of nutrients in tumor cells appears to be a promising route for their differentiation from healthy cells. Finally, properly designed systems entering the cells by means of penetrin-like peptides deserve great attention.

A review of the efficacy and tolerability of recombinant haematopoietic growth factors in bone marrow transplantation.

The clinical benefits of the haematopoietic growth factors (HGFs) granulocyte colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF) in conjunction with bone marrow transplantation (BMT) have been established from numerous phase II/III clinical trials. Trials with filgrastim (recombinant G-CSF) have shown that it reduces the period of severe neutropenia by about one week, which leads to a reduction in infectious complications and earlier discharge from hospital. Similar clinical effects have been shown in placebo-controlled trials with recombinant GM-CSF. The effect of other HGFs on haematopoietic reconstitution has been investigated in animals and preliminary human studies, however, further data are required before their clinical efficacy can be determined. G-CSF is well tolerated in the BMT setting. GM-CSF also appears to be well tolerated at low doses, but increased toxicity may be seen at higher dosages. Clinical studies have also indicated that the HGFs do not stimulate the proliferation of leukaemic cells, furthermore, graft-versus-host disease (GVHD) is not enhanced by the use of growth factors. Pharmacological purging of the bone marrow may lead to a reduction in the granulocyte-macrophage colony-forming unit (CFU-GM) content of transplanted marrow. An alternative purging approach is the positive selection of CD34+ marrow stem cells. This technique may also be used to select stem cells from the peripheral blood for use in conjunction with or as an alternative to autologous or allogeneic BMT.

Influence of metabolic and genetic factors on tumour necrosis factor-alpha and lymphotoxin-alpha production in insulin-dependent diabetes mellitus.

The potential role of tumour necrosis factors (TNFs) in autoimmunity and insulin-dependent diabetes mellitus (IDDM) led us to determine in vitro TNF-alpha and lymphotoxin-alpha (LT-alpha, TNF-beta) production in IDDM patients according to TNF polymorphism. LT-alpha production of peripheral blood mononuclear cells (PBMC) was lower in diabetic subjects (m = 0.30 +/- 0.2 ng.10(-6) cells) than controls (m = 0.68 +/- 0.3 ng.10(-6) cells, p < 0.05), and early age-at-onset was correlated with low LT-alpha production (rs = 0.8, p = 0.0006). TNF-alpha production was the same in patients and controls, but patients with HbA1c > or = 8% had a higher TNF-alpha production (m = 3.05 +/- 1.2 ng.10(-6) cells) than those with HbA1c < 8% (m = 1.31 +/- 0.33 ng.10(-6) cells, p < 0.05). A study of the microsatellite TNFa region close to the LTA gene showed that the presence of the TNFa1 allele in HLA-(DR3) subjects was associated with increased risk of IDDM. TNFa1-positive subjects (both patients and controls) also had lower LT-alpha production than other subjects. These results indicate that low LT-alpha production is an additional risk factor for IDDM and that poor glycaemic control in patients is associated with enhanced PBMC TNF-alpha production which causes an imbalance between TNF-alpha and LT-alpha production in IDDM patient.

[Study of the HLA system and glyoxalase in 31 insulin-dependent diabetics free from micro and macro-angiopathies after more than a 20-year development]. / Etude du système HLA et de la glyoxalase chez 31 sujets diabétiques insulinodépendants indemnes de micro et macro angiopathie après plus de 20 ans d'évolution.

Insulin-dependent diabetics are not equal as concerns vascular complications. Many factors have been incriminated. The object of this study was to determine if a genetic factor protected the insulin-dependent diabetic from vascular complications. The population included 31 unrelated, white insulin-dependent diabetic subjects (18 females and 13 males), with diabetes of over 20 years' duration (21 to 43 years, m +/- SD 27.82 +/- 6.03 years; age at diagnosis: 2 to 57 years, m +/- SD 22.7 +/- 15.19 years). The absence of vascular lesions was checked for by the following investigations: visual acuity, fundoscopic examination, retinal fluorescein angiography (Canon F 60 Z), systolic pressure on the thigh and ankle, Doppler velocimetry, plethysmography of the lower limbs, serum creatinine level, urinary protein. The study of the HLA A, B, DR specificities was carried out using the Tersaki microlymphocytotoxicity assay, those of C4 by high voltage gel electrophoresis followed by hemolytic detection, those of B1 using Alper's method and those of glyoxalase by gel electrophoresis followed by a glutathione redox reaction in order to test for a marker for a possible protective genetic factor against complications. The antigen frequencies found were compared with: 1) Those in the general Caucasian reference population (9th Histocompatibility Workshop, 1984). The study group presented the HLA characteristics known to occur in insulin-dependent diabetes: increase in A30, B8, B18, D6, DR3, DR4, BfF1 and decrease in A3, B7, DR2. Furthermore an increase in the frequency of DRw53, DQw2 and DQw3 alleles was noted.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparison of management of advanced cancer in various organs].

The management of advanced cancer presents the greatest challenge to physicians involved in oncology. There will usually be a large burden of disease; cure is unlikely; and the needs of the patient in terms of pain control and palliation will also be important over and above the direct treatment of the disease. Different issues will arise depending on the site and pathological type of the cancer. Increasingly over the past few years, treatment protocols and guidelines have been developed for different cancers, but these can only be rough guides rather than definite treatment recommendations. Additionally in most cancers advanced disease offers the opportunity for evaluation of new treatments in Phase II studies and other trials. With the new generation of molecular targeted therapies, such as EGFR inhibitors, striking results are being seen in advanced disease that compare favourably with what has been seen previously. Other agents such as those which attack the tumour vasculature may also have promise in this setting. Palliation is also an important aspect of the management of advanced disease, and pain control in particular is an important component of patient management. In summary, the treatment of advanced disease provides a test bed for new agents, but this need to develop better cancer therapies must be balanced against patient needs for a pain-free and comfortable end to life.

[Problems presented by the genetics of atopic dermatitis]. / Problèmes posés par la génétique de la dermatite atopique.

The role of heredity in atopic dermatitis has been known since the 19th century. However, the method of transmission has not been clarified. Studies in twins have been the most interesting and show a greater risk of monozygotes. The work shows a relationship between HLA and atopic dermatitis. Atopic dermatitis is truly a multifactorial illness, the development of which depends not only on one, but several genetic systems, which may be independent or perhaps acting together, and also on environmental factors of which the influence is predominant.