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TMG Research gGmbH aims to help develop a more systematic understanding of how agri-food systems can be transformed as part of a project on the Assessment and Communication of Climate Impacts of Food (CLIF), funded through the International Climate Initiative (IKI) of the German Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV) and jointly implemented with corsus and WWF Germany. This project promotes sustainable consumption patterns and helps companies, policymakers, and consumers choose more sustainable options in relation to food. The main contribution of TMG to this project is in developing a more systematic understanding of how to transform agri-food systems by publishing a series of strategic reports on the current status of agri-food systems and the likely drivers and agents of their transformation. This report is part of the FORESEE (4C) series on The Transformation of Agri-Food Systems in Times of Multiple Crises, which explores the status quo of the current agri-food system in the light of challenges linked to the multiple crises. This part of the series reviews the blind spots and gaps in the debate around agri-food systems transformation and how these hinder the transformation. Furthermore, this report offers recommendations on how to address these gaps to facilitate an agri-food system transformation aligned to the leading themes of people, planet, and prosperity. The report was drafted by TMG with contributions from an extended group of experts.

Cet article consiste en une réflexion conceptuelle d’ordre épistémologique et didactique sur un enseignement de la technologie centré sur le processus de conception technique. En vue de construire une communauté discursive interdisciplinaire scolaire dans ce domaine, nous convions les enseignant·e·s à faire acquérir aux élèves six pratiques épistémiques d’ingénierie : définir un problème technique, générer et sélectionner des solutions en recourant à une approche systématique et itérative, analyser et modéliser, expérimenter et évaluer, communiquer et prendre des décisions. Cespratiques discursives interdisciplinaires caractérisant la pensée design des élèves sont cohérentes avec les pratiques sociotechniques de référence et jouent un rôle central dans le développement d’une culture technique authentique. (DIPF/Orig.), This article consists of an epistemological and didactic conceptual reflection on technology education centred on the engineering design process. In order to build a school interdisciplinary discursive community in this field, we invite teachers to teach students six epistemic engineering practices: defining a technical problem, generating and selecting solutions using a systematic and iterative approach, analysing and modelling, experimenting and evaluating, communicating and making decisions. These interdisciplinary discursive practices characterising students’ design thinking are coherent with the sociotechnical practices of reference and play a central role in the development of an authentic technical culture. (DIPF/Orig.)

Objective To describe a case of an adult female Filipino with hypereosinophilia and bilateral carotid artery aneurysms who subsequently developed bilateral cerebral hemisphere strokes following aneurysm stenting. Case Description A 57-year-old female patient with persistent hypereosinophilia presented with progressively enlarging bilateral neck masses, revealed to be carotid artery aneurysms on computed tomography angiography. Following surgical exploration, she later developed right-sided hemiplegia, aphasia, and right hemianopia. Cranial computed tomography revealed infarcts on both middle cerebral artery territories. Bone marrow biopsy and fluorescent in situ hybridization revealed findings suggestive of hypereosinophilic syndrome. She was started on standard aspirin and statin therapy and was discharged sixteen days after the procedure. Partial improvement of neurologic deficits was noted two months later on follow up. Chemotherapy with imatinib was initiated. Conclusions This patient's prothrombotic state from FIP1L1-PDGFRA–positive hypereosinophilia may have led to large carotid artery aneurysm formation and intramural thrombosis. This case demonstrates a possible and heretofore undocumented neurovascular sequela of hypereosinophilic syndrome.

Ce texte pose les bases conceptuelles d’un cadre d’analyse des relations entre les disciplines scolaires, notamment celles des sciences de la nature et des sciences humaines, et les « Éducations à », afin de mener des analyses comparatives de curriculums dans le monde francophone. Le texte évoque d’abord les principales caractéristiques des « Éducations à » pour ensuite circonscrire les zones de tensions qui découlent de leur prise en charge par les disciplines scolaires. L’assise conceptuelle présentée subséquemment conduit à dégager quatre configurations théoriques pouvant soutenir l’analyse des relations entre les disciplines scolaires et les « Éducations à » sur le plan des finalités éducatives, des apprentissages visés, du statut du savoir disciplinaire et des dispositifs de formation privilégiés., This text lays the conceptual foundations for a framework to analyse the relationships between school disciplines, particularly those in the natural sciences and the humanities, and “Éducations à” in order to conduct comparative analyses of curricula in the French-speaking world. The text first discusses the main characteristics of “Éducations à” and then circumscribes the areas of tension that arise from their handling by school disciplines. The conceptual basis presented subsequently leads to the identification of four theoretical configurations that can support the analysis of the relationships between school disciplines and “Éducations à” in terms of the educational purposes, targeted learning, status of disciplinary knowledge, and preferred modes of instruction.

Nicotinic acetylcholine receptors (nAChRs) are best known to function as ligand-gated ion channels in the nervous system. However, recent evidence suggests that nicotine modulates inflammation by desensitizing non-neuronal nAChRs, rather than by inducing channel opening. Silent agonists are molecules that selectively induce the desensitized state of nAChRs while producing little or no channel opening. A silent agonist of α7 nAChRs has recently been shown to reduce inflammation in an animal model of inflammatory pain. The objective of this study was to determine whether a silent agonist of α7 nAChRs can also effectively modulate inflammation and disease manifestation in an animal model of multiple sclerosis. We first evaluated the effects of various nAChR ligands and of an α7 nAChR-selective silent agonist, 1-ethyl-4-(3-(bromo)phenyl)piperazine (m-bromo PEP), on the modulation of mouse bone marrow-derived monocyte/macrophage (BMDM) numbers, phenotype and cytokine production. The non-competitive antagonist mecamylamine and the silent agonist m-bromo PEP reduced pro-inflammatory BMDM numbers by affecting their viability and proliferation. Both molecules also significantly reduced cytokine production by mouse BMDMs and significantly ameliorated disease in experimental autoimmune encephalomyelitis. Finally, m-bromo PEP also reduced chronic inflammatory pain in mice. Taken together, our results further support the hypothesis that nAChRs may modulate inflammation via receptor desensitization rather than channel opening. α7 nAChR-selective silent agonists may thus be a novel source of anti-inflammatory compounds that could be used for the treatment of inflammatory disorders.

Schweizerische Zeitschrift fur Bildungswissenschaften 42 (2020) 3, S. 537-541 Padagogische Teildisziplin: Schulpadagogik; Fachdidaktik/Sprache und Literatur

Neutrophils play a key role in the innate immunity with their ability to generate and release inflammatory mediators that promote the inflammatory response and consequently restore the hemostasis. As active participants in several steps of the normal inflammatory response, neutrophils are also involved in chronic inflammatory diseases such as asthma, atherosclerosis, and arthritis. Given their dual role in the modulation of inflammation, regulating the inflammatory response of neutrophils has been suggested as an important therapeutic approach by numerous researchers. The neutrophils have a relatively short lifespan, which can be problematic for some in vitro experiments. To address this issue, researchers have used the human monomyelocyte cell line PLB-985 as an in vitro model for exploratory experiments addressing neutrophil-related physiological functions. PLB-985 cells can be differentiated into a neutrophil-like phenotype upon exposure to several agonists, including dimethyl sulfoxide (DMSO). Whether this differentiation of PLB-985 affects important features related to the neutrophil's normal functions (i.e., mitochondrial activity, eicosanoid production) remains elusive, and characterizing these changes will be the focal point of this study. Our results indicate that the differentiation affected the proliferation of PLB-985 cells, without inducing apoptosis. A significant decrease in mitochondrial respiration was observed in differentiated PLB-985 cells. However, the overall mitochondria content was not affected. Immunoblotting with mitochondrial antibodies revealed a strong modulation of the succinate dehydrogenase A, superoxide dismutase 2, ubiquinol-cytochrome c reductase core protein 2 and ATP synthase subunit α in differentiated PLB-985 cells. Finally, eicosanoids (leukotriene B4, 12-hydroxyheptadecatrienoic and 15-hydroxyeicosatetraenoic acids) production was significantly increased in differentiated cells. In summary, our data demonstrate that the differentiation process of PLB-985 cells does not impact their viability despite a reduced respiratory state of the cells. This process is also accompanied by modulation of the inflammatory state of the cell. Of importance, our data suggest that PLB-985 cells could be suitable in vitro candidates to study mitochondrial-related dysfunctions in inflammatory diseases.

Cet article vise à rendre compte des représentations de la pratique interdisciplinaire chez 173 futurs enseignants suisses du primaire. Sur la base d’une modélisation originale de sept configurations théoriques possibles de la pratique interdisciplinaire inscrites dans la continuité selon le degré d’intégration des objets de savoir, un corpus de données constitué d’attributs et de situations emblématiques pour caractériser cette pratique a fait l’objet d’une analyse lexicométrique et d’une analyse de contenu dans une perspective de complémentarité des méthodes d’analyse. Les résultats indiquent que la plupart des futurs enseignants confondent approche interdisciplinaire et deux autres approches intégratives : l’approche par thème et l’approche par projet. Pour les trois quarts d’entre eux, les situations emblématiques proposées relèvent de pratiques hégémonique, pseudo-interdisciplinaire, holistique, multidisciplinaire ou pluridisciplinaire dont le degré d’intégration des objets de savoir varie sur un continuum allant d’un degré négatif à un degré moyen. Seulement le quart d’entre eux conçoit la pratique interdisciplinaire en tant qu’interdisciplinarité au sens strict. Les descriptifs des situations rapportées sont souvent marqués par une identification floue des contributions disciplinaires ou par une absence des considérations épistémologiques des disciplines scolaires. Ces résultats rappellent l’importance d’assurer une solide formation des enseignants sur l’interdisciplinarité en relation avec les spécificités et les enjeux des didactiques disciplinaires. This article aims to report on the representations of interdisciplinary practice among 173 future Swiss primary school teachers. On the basis of an original model of seven possible theoretical configurations of interdisciplinary practice in continuity according to the degree of integration of knowledge objects, a body of data consisting of attributes and emblematic situations to characterize this practice was subjected to lexicometric analysis and content analysis with a view to ensuring complementarity of analytical methods. The results indicate that most future teachers confuse an interdisciplinary approach with two other integrative approaches: the thematic approach and the project approach. For three quarters of them, the emblematic situations proposed are hegemonic, pseudo-interdisciplinary, holistic, multidisciplinary or pluridisciplinary practices whose degree of integration of knowledge objects varies over a continuum ranging from a negative degree to a medium degree. Only a quarter of them conceives interdisciplinary practice as interdisciplinarity in the strict sense. The descriptions of the situations reported are often marked by a vague identification of disciplinary contributions or by an absence of epistemological considerations of school disciplines. These results highlight the importance of ensuring solid teacher training on interdisciplinarity in relation to the specificities and challenges of disciplinary didactics.

High levels and activity of Src kinase are common among breast cancer subtypes, and several inhibitors of the kinase are currently tested in clinical trials. Alterations in mitochondrial activity is also observed among the different types of breast cancer. Src kinase is localized in several subcellular compartments, including mitochondria where it targets several proteins to modulate the activity of the organelle. Although the subcellular localization of other oncogenes modulates the potency of known treatments, nothing is known about the specific role of intra-mitochondrial Src (mtSrc) in breast cancer. The aim of this work was to determine whether mtSrc kinase has specific impact on breast cancer cells. We first observed that activity of mtSrc is higher in breast cancer cells of the triple negative subtype. Over-expression of Src specifically targeted to mitochondria reduced mtDNA levels, mitochondrial membrane potential and cellular respiration. These alterations of mitochondrial functions led to lower cellular viability, shorter cell cycle and increased invasive capacity. Proteomic analyses revealed that mtSrc targets the mitochondrial single-stranded DNA-binding protein, a regulator of mtDNA replication. Our findings suggest that mtSrc promotes aggressiveness of breast cancer cells via phosphorylation of mitochondrial single-stranded DNA-binding protein leading to reduced mtDNA levels and mitochondrial activity. This study highlights the importance of considering the subcellular localization of Src kinase in the development of potent therapy for breast cancer.

Myeloid cells, including proinflammatory monocytes and neutrophils, have important roles in the pathology of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE). These cells infiltrate the CNS in the early stages of disease development and contribute to the inflammatory response that is associated with symptom severity. It is thus crucial to identify and understand new mechanisms that can regulate the CNS infiltration of proinflammatory myeloid cells. Nicotinic acetylcholine receptors (nAChRs) have been increasingly studied for their immune-regulatory properties. In this study, we assessed the ability of nicotine, an nAChR ligand, to modulate proinflammatory myeloid cell numbers within the bone marrow, spleen, blood, and CNS of EAE mice. We found that nicotine significantly inhibits the infiltration of proinflammatory monocytes and neutrophils into the CNS at time points where these cells are known to play critical roles in disease pathology. In contrast, nicotine does not affect the expansion of other monocytes. We also show that nicotine exerts these effects by acting on α7 and α9 nAChR subtypes. Finally, mRNA transcript levels for CCL2 and CXCL2, chemokines involved in the chemotaxis of proinflammatory monocytes and neutrophils, respectively, are reduced in the brain of nicotine-treated EAE mice before the massive infiltration of these cells. Taken together, our data provide evidence that nAChRs can regulate proinflammatory cell infiltration into the CNS, which could be of significant value for the treatment of neuroinflammatory disorders.

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The acute administration of estradiol benzoate (EB) to the ovariectomized (OVX) rat induces low levels of lordosis while sexually appetitive behaviors (e.g., hops, darts, solicitations) are absent, yet the repeated administration of EB results in a behavioral sensitization in which lordosis is potentiated and sexually appetitive behaviors are induced. We have shown that repeated copulation attenuates the sensitization of appetitive sexual behaviors. Here, we assessed which component of male stimulation during copulation is involved in the attenuation. On 8 occasions, sexually experienced OVX Long-Evans rats were treated with 10μgEB and 48h later assigned to one of six groups that differed in their experience on intermediates tests (2-7). One was given repeated access to a male (EB/Male), and another was placed in the copulation chamber alone (EB/Alone) on intermediate tests. Three groups were given one of three somatosensory stimuli by the experimenter: manual flank stimulation (FLS), clitoral stimulation (CLS), or vaginocervical stimulation (VCS). Finally, the control group was left undisturbed in the animal care facility (ACF). Sexual behaviors were measured on Tests 1 and 8. VCS received from the experimenter (VCS) or from the male during copulation (EB/Male) attenuated the magnitude of the sensitization of appetitive sexual behaviors compared with those that were not brought to the testing rooms (ACF), and the effect was most pronounced on sexual solicitations. These results suggest that VCS received during penile intromission inhibits the sensitization of sexually appetitive behaviors by repeated administration of EB. As such, repeated administration of EB may oppose those mechanisms that induce estrous termination, perhaps by sensitizing inhibitory processes within the ventromedial hypothalamus that typically prevent the display of sexual behaviors (i.e., by facilitating disinhibition).

Aspergillus fumigatus is a ubiquitous opportunistic fungal pathogen that can cause aspergillosis in humans. Over the last decade there have been increasing global reports of treatment failure due to triazole resistance. An emerging hypothesis states that agricultural triazole fungicide use causes clinical triazole resistance. Here we test this hypothesis in Hamilton, Ontario, Canada, by examining a total of 195 agricultural, urban, and clinical isolates using 9 highly polymorphic microsatellite markers. For each isolate, the in vitro susceptibilities to itraconazole and voriconazole, 2 triazole drugs commonly used in the management of patients, were also determined. Our analyses suggested frequent gene flow among the agricultural, urban environmental, and clinical populations of A. fumigatus and found evidence for widespread sexual recombination within and among the different populations. Interestingly, all 195 isolates analyzed in this study were susceptible to both triazoles tested. However, compared with the urban population, agricultural and clinical populations showed significantly reduced susceptibility to itraconazole and voriconazole, consistent with ecological niche-specific selective pressures on A. fumigatus populations in Hamilton. Frequent gene flow and genetic recombination among these populations suggest greater attention should be paid to monitor A. fumigatus populations in Hamilton and other similar jurisdictions.

Objective.Previous studies combining biologic disease-modifying antirheumatic drugs (bDMARD) to treat rheumatoid arthritis (RA) have shown an increased risk of infection. However, the risk of infection with concurrent use of denosumab, a biologic agent for the treatment of osteoporosis, and a bDMARD remains unclear. Here, we evaluated the incidence of serious and opportunistic infections in patients treated concurrently with denosumab and a bDMARD and patients treated with a bDMARD alone.Methods.A chart review of patients with RA from 2 Canadian rheumatology practices between July 1, 2010, and July 31, 2014, identified 2 groups of patients: those taking denosumab and a bDMARD concurrently (concurrent group) and those taking only a bDMARD (biologic-alone group). Patients were followed from the time of initiation of denosumab, or a matched index date for the biologic-alone group, to the end of the study or loss to followup. Instances of serious or opportunistic infections were recorded.Results.A total of 308 patients (n = 102 for the concurrent group and n = 206 for the biologic-alone group) were evaluated. Within the concurrent group, 3 serious infection events occurred. Within the biologic-alone group, 4 serious infection events and 1 opportunistic infection event occurred. In both groups, all patients with serious or opportunistic infection recovered, and there were no instances of death during the study period.Conclusion.This study demonstrated a low occurrence of serious and opportunistic infections in patients with RA taking bDMARD, including patients with concurrent denosumab use.

The objective of this study is to describe the way in which two important biological phenomena, namely diffusion and osmosis, are addressed in the classroom. The study builds on extensive research conducted over the past twenty years showing that students’ appropriation of these two phenomena remains partial and incomplete. To understand some of the difficulties these students face in understanding such concepts, we have geared our research toward analysis of classroom practices based on a theoretical framework involving general and specific dimensions of teaching science. Using a case study (a course made up of eight periods), we collected data in three stages: interviews with the teacher regarding his planning; a video recording of the entire course; and feedback interviews with the teacher subsequent to the course. The study’s results show that the difficulties encountered by the students cannot be attributed solely to their personal characteristics (state of development of the scientific mindset, prior learning, etc.). Instead, they appear to be largely associated with teaching practices and the potential these practices hold in terms of allowing students to appropriate these concepts. The results presented in this article are significant in their contribution to improving teaching methods for diffusion and osmosis, and thus to facilitating their understanding by students. The paper also presents an example of a conceptual and methodological framework for the study of classroom practices with a view to addressing the gap between educational research and classroom practice.

It is increasingly clear that nicotinic acetylcholine receptors (nAChRs) are involved in immune regulation, and that their activation can protect against inflammatory diseases. Previous data have shown that nicotine diminishes the numbers of peripheral monocytes and macrophages, especially those of the pro-inflammatory phenotype. The goal of the present study was to determine if nicotine modulates the production of bone marrow -derived monocytes/macrophages. In this study, we first found that murine bone marrow cells express multiple nAChR subunits, and that the α7 and α9 nAChRs most predominant subtypes found in immune cells and their precursors. Using primary cultures of murine bone marrow cells, we then determined the effect of nicotine on monocyte colony-stimulating factor and interferon gamma (IFNγ)-induced monocyte production. We found that nicotine lowered the overall number of monocytes, and more specifically, inhibited the IFNγ-induced increase in pro-inflammatory monocytes by reducing cell proliferation and viability. These data suggested that nicotine diminishes the ratio of pro-inflammatory versus anti-inflammatory monocyte produced in the bone marrow. We thus confirmed this hypothesis by measuring cytokine expression, where we found that nicotine inhibited the production of the pro-inflammatory cytokines TNFα, IL-1β and IL-12, while stimulating the secretion of IL-10, an anti-inflammatory cytokine. Finally, nicotine also reduced the number of pro-inflammatory monocytes in the bone marrow of LPS-challenged mice. Overall, our data demonstrate that both α7 and α9 nAChRs are involved in the regulation of pro-inflammatory M1 monocyte numbers.

The incorporation of a carboxylic acid within in a series of 3-amido-4-aryl substituted piperidines (represented by general structure 32) led to the discovery of potent, zwitterionic, renin inhibitors with improved off-target profiles (CYP3A4 time-dependent inhibition and hERG affinity) relative to analogous non-zwitterionic inhibitors of the past (i.e., 3). Strategies to address the oral absorption of these zwitterions are also discussed within.

The discovery and SAR of a series of potent renin inhibitors possessing a novel biaryl scaffold are described herein. Molecular modeling revealed that the cyclopropylamide spacer present in 1 can be replaced by a simple, substituted aromatic ring such as a toluene in 2. The resulting compounds exhibit subnanomolar renin IC50 and good oral bioavailability in rats.

This paper deals with the application of fractional system identification to lead acid battery state of charge estimation. Fractional behavior of lead acid batteries is justified. A fractional system identification method recently developed is presented and a new fractional model of the battery is proposed. Based on parameter variations of this model, a state of charge estimation method is presented. Validation tests of this method on unknown state of charge are carried out. These validation tests highlights that the proposed estimation method gives a state of charge estimation with an error close to 5% whatever the operating temperature.

Background: Recommendations for the management of left ventricular (LV) systolic dysfunction in the general population and patients with end-stage renal disease (ESRD) include the use of angiotensin-converting enzyme (ACE) inhibitors and β-blockers. Limited data from the literature suggest that these pharmacological agents may be underused in patients with ESRD. The goal of this study is to describe the use of these medications and investigate barriers to their use in dialysis patients. Methods: We prospectively studied 420 hemodialysis patients. Diagnosis of systolic dysfunction was based on echocardiogram results. Use of cardiac medication was recorded for all patients with systolic dysfunction, and a questionnaire was administered to nephrologists to determine the basis for decisions concerning ACE-inhibitors and β-blockers use/nonuse. Results: Forty-seven patients (11%) were found to have an LV ejection fraction of 40% or less. Of those, 72% were administered a β-blocker and 36% were administered an ACE inhibitor. Only 12 patients (25.5%) were administered a combination of β-blocker and ACE inhibitor. Reasons indicated by nephrologists for not prescribing these medications were "concern about adverse reactions (eg, hypotension, hyperkalemia)" in 88% of cases, "adequate control of symptoms with ultrafiltration" in 38%, "unproven benefit" in 25%, and "unfavorable risk-benefit ratio" in 17%. Medication costs and concern about patient compliance were not identified as significant concerns by physicians. Conclusion: Only 25.5% of patients with ESRD with LV systolic dysfunction receive appropriate treatment. Concern regarding adverse reactions was the most frequent reason indicated by nephrologists for not prescribing ACE inhibitors and β-blockers.

A series of substituted 5-, 6-, and 7-azaindoles were prepared via the Hemetsberger-Knittel reaction. In general, better yields were obtained at higher temperatures and shorter reaction times than required for the formation of the analogous indoles, and in some cases, only decomposition occurred below a minimum temperature. The resulting templates offer up to five sites for subsequent functionalization to allow a wide range of chemical diversity.

The SAR from our peptide libraries was exploited to design a series of potent deoxybenzoin PTP-1B inhibitors. The introduction of an ortho bromo substituent next to the difluoromethylphosphonate warhead gave up to 20-fold increase in potency compared to the desbromo analogues. In addition, these compounds were orally bioavailable and active in the animal models of non-insulin dependent diabetes mellitus (NIDDM).

The use of the 3D detector geometry, where the electrodes go through the bulk of the semiconductor instead of sitting at the surface, allows the life of semiconductor devices to be extended in harsh radiation environments. This geometry also enables the use of less than optimal material, i.e. with poorer charge collection efficiency. Three different production methods have been investigated: dry etching, laser machining and photoelectrochemical etching. The electrical characteristics of the resulting test devices made in low resistivity silicon and gallium arsenide have been studied. Some of these 3D detectors were characterised after irradiation by 300 MeV/ c pions, up to a fluence of 10 14 π/cm 2 at the Paul Scherrer Institute, Villigen.

The COX-2 inhibitor DFP [5,5-dimethyl-3-(2-propoxy)-4-methanesulfonylphenyl)-2(5H)-furanone] was found to have a long half-life in humans. Analogues have been characterized in order to optimize pharmacokinetics. This has lead to the discovery of 5(S)-(5-ethyl-5-methyl-3-(2-propoxy)-4-methanesulfonylphenyl)-2(5H)-furanone analogue 11 a potent and selective COX-2 inhibitor which is metabolized to a greater extent than DFP upon incubation with rat and human hepatocytes, suggesting a shorter half-life in humans.

Inhibitors of PTP-1B could be therapeutically beneficial in the treatment of type 2 diabetes. Owing to the large number of phosphatases in the cell, inhibitors against PTP-1B must not only be potent but selective as well. N-Benzoyl-L-glutamyl-[4-phosphono(difluoromethyl)]-L-phenylalanine-[4-phosphono(difluoro-methyl)]-L-phenylalanineamide (BzN-EJJ-amide) is a low nanomolar inhibitor of PTP-1B that shows selectivity over several protein tyrosine phosphatases. To gain an insight into the basis of its potency and selectivity, we evaluated several analogues of the inhibitor and introduced amino acid substitutions into PTP-1B by site-directed mutagenesis. We also determined the crystal structure of PTP-1B in complex with BzN-EJJ-amide at 2.5 A resolution. Our results indicate that the high inhibitory potency is due to interactions of several of its chemical groups with specific protein residues. An interaction between BzN-EJJ-amide and Asp48 is of particular significance, as substitution of Asp48 to alanine resulted in a 100-fold loss in potency. The crystal structure also revealed an unexpected binding orientation for a bisphosphonate inhibitor on PTP-1B, where the second difluorophosphonomethyl phenylalanine (F(2)PMP) moiety is bound close to Arg47 rather than in the previously identified second aryl phosphate site demarked by Arg24 and Arg254. Our results suggest that potent and selective PTP-1B inhibitors may be designed by targeting the region containing Arg47 and Asp48.