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Purpose: To evaluate the reliability of the Deauville score (DS) in therapy response assessment and to define the prognostic value of the metabolic response of end of induction (EOI) [18F]FDG PET (PET) in follicular lymphoma patients. Methods: Adult patients with untreated grade 1–3a FL/ stage II‐IV enrolled in the multicentre, prospective, phase III FOLL12 trial (NCT02063685) were randomized to receive standard immunochemotherapy followed by rituximab maintenance (standard arm) versus standard immunochemotherapy followed by response-adapted post‐induction management (experimental arm). Baseline and EOI PET were mandatory for the study. All PET scans were centralized on the WIDEN® platform and classified according to DS in a blind independent central review. DS1–3 was considered negative (CMR), whereas DS4‐5 was considered positive (not CMR). The primary endpoint was PFS. The main secondary endpoint was overall survival (OS). Results: Overall, 807 follicular lymphoma patients—52% women, 89% stage III-IV disease, 40% with a high-risk FLIPI-2 score (3–5)—were enrolled in the study; 729 (90.4%) baseline and EOI PET were available for the analysis. EOI PET was positive (DS4–5) in 88/729 (12.1%) cases. Overall inter-reviewer agreement on PET pos/neg result was 0.92, while agreement on positive and negative cases was 0.77 and 0.94, respectively. The median follow-up was 69 months; 247 events were registered in the 5-yr follow-up, with a 5-yr PFS of 67% (95%CI: 63%–70%). The 5-yr PFS rate for PET neg (DS1–3) and PET pos (DS4–5) patients was 71% (95%CI: 67%–75%) and 36% (95%CI: 25%–46%), respectively, with HR 3.49 (95%CI: 2.57–4.72). Five-year PFS was worse as DS increased, with 74% (70%–78%), 58% (48%–67%; HR 1.71; p = 0.001)] and 36% (25%–46%; HR 3.88; p < 0.001) in DS1–2, DS3 and DS4–5, respectively. EOI PET maintained its prognostic value in both the standard and experimental arms. In the whole population, 5-yr OS was 94% (95%CI: 92%–96%), with 96% (95%CI: 94–97) and 82% (95%CI: 72%–89%) in EOI PET negative (DS1–3) and positive (DS4–5), respectively (HR 4.48; p < 0.001). When DS was associated with FLIPI-2, patients with DS3 or DS1–2 with high FLIPI-2 (3–5) experienced worse OS than patients with DS1–2 and low FLIPI-2 (1–2) (p = 0.003). Conclusion: This study shows that DS is a reliable prognostic tool to evaluate EOI PET in follicular lymphoma patients, with prognostic value maintained both in the standard and experimental arms, making metabolic imaging a robust tool to assess response in FL. Moreover, although preliminary, this study provides further information on DS3 patients, who are considered as CMR but show a less favourable PFS than DS1–2 patients. [ABSTRACT FROM AUTHOR]

Designing metal sites into de novo proteins has significantly improved, recently. However, identifying the minimal coordination spheres, able to encompass the necessary information for metal binding and activity, still represents a great challenge, today. Here, we test our understanding with a benchmark, nevertheless difficult, case. We assemble into a miniature 28-residue protein, the quintessential elements required to fold properly around a FeCys4 redox center, and to function efficiently in electron-transfer. This study addresses a challenge in de novo protein design, as it reports the crystal structure of a designed tetra-thiolate metal-binding protein in sub-Å agreement with the intended design. This allows us to well correlate structure to spectroscopic and electrochemical properties. Given its high reduction potential compared to natural and designed FeCys4-containing proteins, we exploit it as terminal electron acceptor of a fully artificial chain triggered by visible light. Living organisms regulate their energy demand by managing electron trafficking in complex transport chains. Here, the authors pioneer a fully artificial electron chain triggered by visible light using designed proteins, unlocking possibilities in bioengineering. [ABSTRACT FROM AUTHOR]

Checkpoint inhibitors have significantly changed the prognosis of patients with relapsing refractory classical Hodgkin's lymphoma (cHL), demonstrating excellent results in heavily pretreated patients. However, there is still limited data on the real-world experience with PD-1 inhibitors in cHL. Within the context of the Apulian hematological network (Rete Ematologica Pugliese, REP), we performed a retrospective, multicenter analysis of 66 patients with relapsing refractory cHL who had received PD-1 inhibitors in the non-trial setting. Forty-three patients (65%) were treated with nivolumab and 23 (35%) with pembrolizumab. Thirty-one (47%) and 8 (12%) patients underwent autologous or allogeneic stem cell transplantation prior to checkpoint inhibitor therapy, respectively. The median number of lines of treatment attempted prior to PD-1 inhibitor therapy was 4 (range, 3 to 7). All patients had received brentuximab vedotin prior to checkpoint inhibitor therapy. The overall response rate to PD-1 inhibitors therapy was 70% (47% complete remission (CR) and 23% partial remission (PR)). Twenty-four immune-related adverse events (19 (80%) grades 1–2; 5 (20%) grades 3–4) were documented (4 gastrointestinal, 4 hepatic, 6 fever, 4 hematological, 3 dermatological, 3 allergic rhinitis). Toxicity resolved in all patients, and there were no deaths attributed to checkpoint inhibitor therapy. After a median follow-up of 26 months (range 3–72 months), 54 patients (82%) are alive, and 12 (18%) died. The cause of death was attributed to disease progression in 9 patients and sepsis in 3 patients. After PD-1 inhibitor therapy, 22 patients (33%) relapsed or progressed. The overall survival and progression-free survival at 5 years were 65% and 54%, respectively. This study confirms the efficacy and tolerability of PD-1 inhibitor therapy in relapsed refractory cHL in a real-world setting, demonstrating similar clinical outcomes and toxicity profiles compared to clinical studies. [ABSTRACT FROM AUTHOR]

Background and Objectives: UPARANT has emerged as a novel therapeutic agent with the potential to treat ocular diseases as assessed by studies in animal models. Since limited information is available on the pharmacokinetics of UPARANT, the aim of this study is to evaluate its pharmacokinetics after single and multiple ascending dose (SAD and MAD) administration in rats. Methods: Male (n = 27) and female (n = 27) Sprague-Dawley rats were divided into six groups (n = 9/sex/group). UPARANT was administered via subcutaneous injection as single (10, 50 or 100 mg/kg; day 1) and multiple (10, 50 or 100 mg/kg/day; 7 consecutive days; day 7) dosing. Blood samples were collected on day 1 (pre-dose, 0.5, 1, 2, 4, 8 and 24 h post dose) and day 7 (pre-dose, 0.5, 1, 2, 4, 8, 24, 48 and 192 h post dose). The plasma concentration of UPARANT was determined by a validated liquid chromatography mass spectrometry method. Results: The plasma concentration-time profiles of UPARANT were similar in SAD and MAD administration in both male and female rats. The compound reached maximum plasma concentration (Cmax) at 1–2 h with a slow apparent plasma clearance and a moderate apparent volume of distribution. Moreover, SAD administration revealed a non-proportional increase in Cmax and in the area under the plasma concentration-time curve (AUCinf), whereas a dose-proportional increase in AUCinf was shown after MAD administration. Regarding the extent of accumulation, the data suggest negligible accumulation of the compound after multiple administrations. Conclusion: The pharmacokinetics of UPARANT were not sex-related, and there was negligible accumulation in plasma after 7 days of treatment. However, the compound exhibited no dose-proportional pharmacokinetics after single and multiple ascending subcutaneous dosing. [ABSTRACT FROM AUTHOR]

Proliferative retinopathies (PR) lead to an increase in neovascularization and inflammation factors, at times culminating in pathologic rubeosis iridis (RI). In mice, uveal puncture combined with injection of hypoxia-conditioned media mimics RI associated with proliferative retinopathies. Here, we investigated the effects of the urokinase plasminogen activator receptor (uPAR) antagonist—UPARANT—on the angiogenic and inflammatory processes that are dysregulated in this model. In addition, the effects of UPARANT were compared with those of anti-vascular endothelial growth factor (VEGF) therapies. Administration of UPARANT promptly decreased iris vasculature, while anti-VEGF effects were slower and less pronounced. Immunoblot and qPCR analysis suggested that UPARANT acts predominantly by reducing the upregulated inflammatory and extracellular matrix degradation responses. UPARANT appears to be more effective in comparison to anti-VEGF in the treatment of RI associated with PR in the murine model, by modulating multiple uPAR-associated signaling pathways. Furthermore, UPARANT effectiveness was maintained when systemically administered, which could open to novel improved therapies for proliferative ocular diseases, particularly those associated with PR. Key messages: • Further evidence of UPARANT effectiveness in normalizing pathological iris neovascularization. • Both systemic and local administration of UPARANT reduce iris neovascularization in a model associated with proliferative retinopathies. • In the mouse models of rubeosis iridis associated with proliferative retinopathy, UPARANT displays stronger effects when compared with anti-vascular endothelial growth factor regimen. [ABSTRACT FROM AUTHOR]

The International Prognostic Score (IPS) is the most commonly used risk stratification tool for patients with advanced Hodgkin lymphoma (HL). It incorporates seven clinical parameters independently associated with a poorer outcome: male sex, age, stage IV, hemoglobin level, white blood cell and lymphocyte counts, and albumin level. Since the development of the IPS, there have been significant advances in therapy and supportive care. Recent studies suggest that the IPS is less discriminating due to improved outcomes with ABVD therapy. The aim of the present study was to asses if classic prognostic factors maintain their prognostic meaning at the time of response-adapted treatment based on interim PET scans. We evaluated the prognostic significance of IPS in the 520 advanced stage HL patients enrolled in the PET-guided, HD0801 trial in which PET2-positive patients underwent a more intense treatment with an early stem-cell transplantation after 2 cycles of ABVD. We observed that in these patients, the IPS completely loses its prognostic value together with all the single parameters that contribute to the IPS. Furthermore, neutrophils, monocytes, lymphocytes, and the ratio among them also no longer had any predictive value. We believe that the substantial improvement in survival outcomes in PET2-positive patients treated with early autologous transplantation could explain the complete disappearance of the residual prognostic significance of the IPS. [ABSTRACT FROM AUTHOR]

Puncture-induced iris neovascularization (rubeosis iridis; RI) in mice is associated with upregulation of extracellular matrix (ECM) degradation and inflammatory factors. The anti-angiogenic and anti-inflammatory efficacy of UPARANT in reducing RI was determined by noninvasive, in vivo iris vascular densitometry, and confirmed in vitro by quantitative vascular-specific immunostaining. Intravitreal administration of UPARANT successfully and rapidly reduced RI to non-induced control levels. Molecular analysis revealed that UPARANT inhibits formyl peptide receptors through a predominantly anti-inflammatory response, accompanied with a significant reduction in ECM degradation and inflammation markers. Similar results were observed with UPARANT administered systemically by subcutaneous injection. These data suggest that the tetrapeptide UPARANT is an effective anti-angiogenic agent for the treatment of RI, both by local and systemic administrations. The effectiveness of UPARANT in reducing RI in a model independent of the canonical vascular endothelial growth factor (VEGF) proposes an alternative for patients that do not respond to anti-VEGF treatments, which could improve treatment in proliferative ocular diseases. Key messages: UPARANT is effective in the treatment of rubeosis iridis, both by local and systemic administrations. UPARANT can reduce VEGF-independent neovascularization. [ABSTRACT FROM AUTHOR]

This study reports a retrospective multicenter experience by the Rete Ematologica Pugliese (REP) over the past 16 years, aiming to compare the patients characteristics and outcomes of 21 brentuximab vedotin (BV)-pre-treated patients to 51 patients who received reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (SCT) without prior BV. In total, 72 patients with classical Hodgkin's lymphomas who received allogeneic SCT were retrospectively studied. Prior use of BV had no effect on either engraftment or the incidence and severity of acute graft versus host disease (GVHD). Indeed, a lower incidence of chronic GVHD was observed in the BV group, with a 43% cumulative incidence at 3 years versus 47% in the no BV group, although this was not statistically significant. Despite the low incidence of chronic GVHD, survival was not worse in the BV-treated group: 3-year progression-free survival (PFS) was 53%, 3-year overall survival (OS) was 62%, 3-year non-relapse mortality (NRM) was 24%. In the no BV group, the 3-year PFS was 33%, 3-year OS was 44%, and 3-year NRM was 14%. In chemorefractory patients at the time of transplant, we found a statistically significant difference in PFS between the BV and no BV groups (51% vs. 10%, p = 0.013). [ABSTRACT FROM AUTHOR]

Brentuximab vedotin (BV) shows a high overall response rate (ORR) in relapsed/refractory (R/R) Hodgkin lymphoma (HL) after autologous transplant (ASCT). The aim of this multicenter study, conducted in nine Hematology Departments of Rete Ematologica Pugliese, was to retrospectively evaluate the efficacy and safety of BV as salvage therapy and as bridge regimen to ASCT or allogeneic transplant (alloSCT) in R/R HL patients. Seventy patients received BV. Forty-five patients (64%) were treated with BV as bridge to transplant:16 (23%) patients as bridge to ASCT and 29 (41%) as bridge to alloSCT. Twenty-five patients (36%), not eligible for transplant, received BV as salvage treatment. The ORR was 59% (CR 26%). The ORR in transplant naïve patients was 75% (CR 31%). In patients treated with BV as bridge to alloSCT, the ORR was 62% (CR 24%). In a multivariate analysis, the ORR was lower in refractory patients (p < 0.005). The 2y-OS was 70%. The median PFS was 17 months. Ten of the 16 (63%) naïve-transplant patients received ASCT, with 50% in CR before ASCT. In the 29 patients treated with BV as bridge to alloSCT, 28 (97%) proceeded to alloSCT with 25% in CR prior to alloSCT. The most common adverse events were peripheral neuropathy (50%), neutropenia (29%) and anemia (12%). These data suggest that BV is well tolerated and very effective in R/R HL, producing a substantial level of CR. BV may also be a key therapeutic agent to achieve good disease control before transplant, improving post- transplant outcomes, also in refractory and heavily pretreated patients, without significant overlapping toxicities with prior therapies. [ABSTRACT FROM AUTHOR]

Background: Inflammation plays a key role in the pathogenesis of several chronic diseases. The urokinase plasminogen activator receptor (uPAR) exerts a plethora of functions in both physiological and pathological processes, including inflammation. Objective and design: In this study, we evaluated the anti-inflammatory effect of a novel peptide ligand of uPAR, UPARANT, in different animal models of inflammation. Subjects and treatment: Rats and mice were divided in different groups ( n = 5) for single or repeated administration of vehicle (9% DMSO in 0.9% NaCl), UPARANT (6, 12 and 24 mg/kg) or dexamethasone (2 mg/kg). Animals were subjected to carrageenan-induced paw oedema or zymosan-induced peritonitis. Methods: UPARANT effects were tested on: (1) the carrageenan-induced paw oedema volume, (2) the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the nitrite/nitrate (NOx) levels in the paw exudates, (3) cells recruitment into the peritoneal cavity after zymosan injection and (4) NOx levels in the peritoneal lavage. Results: UPARANT (12 and 24 mg/kg) reduced inflammation in both experimental paradigms. Analysis of pro-inflammatory enzymes revealed that administration of UPARANT reduced iNOS, COX2 and NO over-production. Conclusions: Our study provides a solid evidence that UPARANT reduces the severity of inflammation in diverse animal models, thus representing a novel anti-inflammatory drug with potential advantages with respect to the typical steroidal agents. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Angiogenesis and inflammation characterise proliferative diabetic retinopathy (PDR), a major complication of diabetes mellitus. However, the impact of inflammation on the pathogenesis of PDR neovascularisation has not been elucidated. Here, we assessed the capacity of PDR vitreous fluid to induce pro-angiogenic/proinflammatory responses in endothelium and the contribution of the inflammation-related pattern recognition N-formyl peptide receptors (FPRs) in mediating these responses. Methods: Pooled and individual pars plana vitrectomy-derived PDR vitreous fluid ('PDR vitreous') samples were assessed in endothelial cell proliferation, motility, sprouting and morphogenesis assays, and for the capacity to induce proinflammatory transcription factor activation, reactive oxygen species production, intercellular junction disruption and leucocyte-adhesion molecule upregulation in these cells. In vivo, the pro-angiogenic/proinflammatory activity of PDR vitreous was tested in murine Matrigel plug and chick embryo chorioallantoic membrane (CAM) assays. Finally, the FPR inhibitors Boc-Phe-Leu-Phe-Leu-Phe (Boc-FLFLF) and Ac- l-Arg-Aib- l-Arg- l-Cα(Me)Phe-NH tetrapeptide (UPARANT) were evaluated for their capacity to affect the biological responses elicited by PDR vitreous. Results: PDR vitreous activates a pro-angiogenic/proinflammatory phenotype in endothelial cells. Accordingly, PDR vitreous triggers a potent angiogenic/inflammatory response in vivo. Notably, the different capacity of individual PDR vitreous samples to induce neovessel formation in the CAM correlates with their ability to recruit infiltrating CD45 cells. Finally, the FPR inhibitor Boc-FLFLF and the novel FPR antagonist UPARANT inhibit neovessel formation and inflammatory responses triggered by PDR vitreous in the CAM assay. Conclusions/interpretation: This study provides evidence that inflammation mediates the angiogenic activity of PDR vitreous and paves the way for the development of FPR-targeting anti-inflammatory/anti-angiogenic approaches for PDR therapy. [ABSTRACT FROM AUTHOR]

In the article entitled "The classic prognostic factors in advanced Hodgkin's lymphoma patients are losing their meaning at the time of Pet-guided treatments", the affiliation of Armando Santoro should be corrected as follows: [ABSTRACT FROM AUTHOR]

Erythropoietin (Epo) is the crucial cytokine regulator of red blood cell production, and recombinant human erythropoietin (rHuEpo) is widely used in clinical practice for the treatment of anemia, primarily in kidney disease and in cancer. Increasing evidence suggests several biological roles for Epo and its receptor, Epo-R, unrelated to erythropoiesis, including angiogenesis. Epo-R has been found expressed in various non-haematopoietic cells and tissues, and in cancer cells. Here, we detected the expression of Epo-R in bone marrow-derived macrophages (BMMAs) from multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) patients and assessed whether Epo/Epo-R axis plays a role in MM macrophage-mediated angiogenesis. We found that Epo-R is over-expressed in BMMAs from MM patients with active disease compared to MGUS patients. The treatment of BMMAs with rHuEpo significantly increased the expression and secretion of key pro-angiogenic mediators, such as vascular endothelial growth factor, hepatocyte growth factor and monocyte chemotactic protein (MCP-1/CCL-2), through activation of JAK2/STAT5 and PI3 K/Akt pathways. In addition, the conditioned media harvested from rHuEpo-treated BMMAs enhanced bone marrow-derived endothelial cell migration and capillary morphogenesis in vitro, and induced angiogenesis in the chorioallantoic membrane of chick embryos in vivo. Furthermore, we found an increase in the circulating levels of several pro-angiogenic cytokines in serum of MM patients with anemia under treatment with Epo. Our findings highlight the direct effect of rHuEpo on macrophage-mediated production of pro-angiogenic factors, suggesting that Epo/Epo-R pathway may be involved in the regulation of angiogenic response occurring in MM. [ABSTRACT FROM AUTHOR]

The design, synthesis, and metal-binding properties of DF3, a new de novo designed di-iron protein model are described (“DF” represents due ferri, Italian for “two iron,” “di-iron”). DF3 is the latest member of the DF family of synthetic proteins. They consist of helix–loop–helix hairpins, designed to dimerize and form an antiparallel four-helix bundle that encompasses a metal-binding site similar to those of non-heme carboxylate-bridged di-iron proteins. Unlike previous DF proteins, DF3 is highly soluble in water (up to 3 mM) and forms stable complexes with several metal ions (Zn, Co, and Mn), with the desired secondary structure and the expected stoichiometry of two ions per protein. UV–vis studies of Co(II) and Fe(III) complexes confirm a metal-binding environment similar to previous di-Co(II)- and di-Fe(III)-DF proteins, including the presence of a μ-oxo-di-Fe(III) unit. Interestingly, UV–vis, EPR, and resonance Raman studies suggest the interaction of a tyrosine adjacent to the di-Fe(III) center. The design of DF3 was aimed at increasing the accessibility of small molecules to the active site of the four-helix bundle. Indeed, binding of azide to the di-Fe(III) site demonstrates a more accessible metal site compared with previous DFs. In fact, fitting of the binding curve to the Hill equation allows us to quantify a 150% accessibility enhancement, with respect to DF2. All these results represent a significant step towards the development of a functional synthetic DF metalloprotein. [ABSTRACT FROM AUTHOR]

Whilst there is an ever-growing literature on the economic and political aspects of ‘globalization,’ at present there are few studies analyzing how intergovernmental organizations have reacted to this phenomenon. This article aims to fill this gap by analyzing the response to globalization of UNESCO, one of the least studied organizations of the UN constellation. Addressing the global orientation of some of the current programs, this article shows how a recent re-evaluation of scientific humanism—the main philosophical framework contributing to the creation of UNESCO—has influenced both UNESCO’s self-understanding and its understanding of globalization. Scientific humanism is a philosophical utopia that couples the advance of scientific knowledge with the diffusion of a common philosophical framework and promotes a universal system of education in order to establish a global community. Based on the philosophical appeal of a culture of peace based on science, humanism and human rights, UNESCO’s representation of globalization represents an intriguing example of how our global future may be conceived and, to some extent, realized. [ABSTRACT FROM AUTHOR]

Peptide-based models have an enormous impact for the development of metalloprotein models, as they seem appropriate candidates to mimic both the structural characteristics and reactivity of the natural systems. Through the de novo design of four-helix bundles, we developed the DF (Due Ferri) family of artificial proteins, as models of di-iron and di-manganese metalloproteins. The goal of our research is to elucidate how the electrostatic environment, polarity and solvent accessibility of the metal-binding site, influence the functional properties of di-iron proteins. The first two subsets of the DF protein family, DF1 and DF2, consist of two non-covalently associated helix-loop-helix motifs, which bind the di-metal cofactor near the center of the structure. The DF2 subset was designed to improve the properties of DF1: DF2 and DF2t have several changes in their sequences to improve solubility and metal ion access, as well as a change in the loop connecting the two helices. In order to evaluate how these changes affect the overall structure of the model proteins, we solved the NMR structures of the di-Zn(II) complexes of DF2 and DF2t, and compared these structures with those recently obtained from X-ray crystallography. Further, we examined the thermodynamic consequences associated with the mutations, by measuring the stability of DF2t in the presence of different metal ions, and comparing the results with the data already obtained for DF2. Taken together, analysis of all the data showed the importance of the turn conformation in the design and stability of four-helix bundle. [ABSTRACT FROM AUTHOR]

Protein design provides an attractive approach to test the essential features required for folding and function. Previously, we described the design and structural characterization in solution of mimochromes, a series of miniaturized metalloproteins, patterned after the F-helix of the hemoglobin β-chain. Mimochromes consist of two medium-sized helical peptides, covalently linked to the deuteroporphyrin. CD and NMR characterization of the prototype, mimochrome I, revealed that the overall structure conforms well to the design. However, formation of Δ and Λ diastereomers was observed. To overcome the problem of diastereomer formation, we re-designed mimochrome I, by engineering intramolecular, interchain interactions. The resulting model was mimochrome IV: the solution structural characterization showed the presence of the Λ isomer as a unique form. To examine the extent to which the stereochemical stability and uniqueness of mimochrome IV was retained in the solid state, the crystal structure of Co(III)-mimochrome IV was solved by X-ray diffraction, and compared to the solution structure of the same derivative. Co(III)-mimochrome IV structures, both in solution and in the solid state, are characterized by the following common features: a bis-His axial coordination, a Λ configuration around the metal ion, and a predominant helical conformation of the peptide chains. However, in the crystal structure, intrachain Glu1–Arg9 ion pairs are preferred over the designed, and experimentally found in solution, interchain interactions. This ion pairing switch may be related to strong packing interactions. [ABSTRACT FROM AUTHOR]

Certain chemokines act as natural antagonists of human immunodeficiency virus (HIV) by blocking key viral coreceptors, such as CCR5 and CXCR4, on the surface of susceptible cells. Elucidating the structural determinants of the receptor-binding and HIV-inhibitory functions of these chemokines is essential for the rational design of derivative molecules of therapeutic value. Here, we identify the structural determinants of CCR5 recognition and antiviral activity of the CC chemokine RANTES, showing that critical residues form a solvent-exposed hydrophobic patch on the surface of the molecule. Moreover, we demonstrate that the biological function is critically dependent on dimerization, resulting in the exposure of a large (∼180 Å2), continuous hydrophobic surface. Relevant to the development of novel therapeutic approaches, we designed a retroinverted RANTES peptide mimetic that maintained both HIV- and chemotaxis-antagonistic functions. [ABSTRACT FROM AUTHOR]

The coordination state of Fe(III)- and Fe(II)-mimochrome I, a covalent peptide-deuteroheme sandwich involving two nonapeptides bearing a histidine residue in a central position, was studied by UV-visible, EPR, and resonance Raman spectroscopy. The ferric and ferrous states of this new iron species mainly exist, at pH 7, in a low-spin hexacoordinate form with two axial histidine ligands coming from the peptide chains. A minor amount of high-spin form for the ferric state is also present at pH 7. However, it is mainly high-spin at pH 2 or in DMSO. Fe(II)-mimochrome I binds CO with an affinity comparable to that of myoglobin and hemoglobin. Fe(III)-mimochrome I reacts with alkylhydroxylamine and arylhydrazines, leading to the corresponding Fe(II)-nitrosoalkyl and Fe(III)-σ-aryl complexes, respectively. These reactions were greatly dependent on the solvent used and on the pH, and were much slower than the corresponding reactions performed by deuterohemin in the presence of excess imidazole. All these results indicate that the reactivity of iron-mimochrome I is controlled by the binding of the peptide chains to the iron. The reactivity shown by this complex at neutral pH is intermediate between that observed for iron porphyrins in the presence of excess imidazole and that of hemoproteins characterized by a strong bis-histidine axial coordination, such as cytochrome b5. Fe(III)-mimochrome I is able to catalyze styrene epoxidation by using a [Fe(III)-mimochrome I]/[H2O2]/[stryrene] ratio of 1 : 10 : 2000 in phosphate buffer solution (pH 7.2) containing 2% CTAB both under strictly anaerobic conditions and in the presence of oxygen, at 0 °C. [ABSTRACT FROM AUTHOR]

A synthetic, terminally blocked homohexapeptide from α-aminoisobutyric acid has been examined by single-crystal X-ray diffraction and the structure refined to R = 0.047. The compound is folded into almost two turns of a 3-helix, stabilized by four consecutive intramolecular N-H⋯·O=C H-bonds. An asymmetric covalent geometry for the α-aminoisobutyric acid residues, known to be responsible for the onset of the 3-helix in homopeptides from this C-dialkylated α-aminoacid on the basis of a theoretrical conformational analysis, has been experimentally found also in this structure. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia with hand-mirror cells (HMC) was diagnosed in nine adult patients. Blast HMC were seen only in the bone marrow (12-57% range). Cytochemical studies revealed a positive reaction to tartrate-sensitive acid phosphatase in the tail portion of the cells in seven cases, with a strong, localized cytoplasmic reaction in four. Leukemic cells lacked surface immunoglobulins and were E rosette negative in all cases. Normal levels of adenosine deaminase activity (ADA) were found in five of the seven patients. Electron microscope studies confirmed the hand-mirror shape of the cell. These HMC contained large numbers of mitochondria and microspikes in the handle portion of the cell. The patients failed to respond to initial conventional ALL chemotherapy, but the prolonged survival with passable health of the majority of these, despite their lack of complete remission, is emphasized. [ABSTRACT FROM AUTHOR]

Here we report the de novo design and NMR structure of a four-helical bundle di-iron protein with phenol oxidase activity. The introduction of the cofactor-binding and phenol-binding sites required the incorporation of residues that were detrimental to the free energy of folding of the protein. Sufficient stability was, however, obtained by optimizing the sequence of a loop distant from the active site. [ABSTRACT FROM AUTHOR]

The objective of this study was to make a contribution to the debate on the cause-effect relationship between low-dose exposure to benzene and onset of hemopathies. We report the case of a coke plant worker suffering from aplastic anemia. Before being hired at the coke plant, he underwent a medical examination including a blood cell count: no disease or abnormalities of the blood crasis were found. For 3 years the patient was then exposed to gas containing-as measured in environmental investigation carried out at the coke plant-concentrations of benzene lower than TLV-TWA ACGIH (measured values 21-109 μg/m). In the absence from the patient's history of any exposure to other myelotoxic agents and of any earlier pathology causing aplastic anemia, we assume there is a relationship between exposure to low levels of benzene and onset of the disease. However, it is very important to consider that exposure to low levels of benzene could promote myelotoxic reactions when the working environment contains other substances that may act synergstically or compete for the same metabolism sites, or when carcinogenic substances are present in the working environment. [ABSTRACT FROM AUTHOR]