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Heterogeneous catalysis is an important area of research that generates data as intricate as the phenomenon itself. Complexity is inherently coupled to the function of the catalyst and advance in knowledge can only be achieved if this complexity is adequately captured and accounted for. This requires integration of experiment and theory, high data quality and quality control, close interdisciplinary collaboration, and sharing of data and metadata, which is facilitated by the application of joint data management strategies. This Viewpoint Article first discusses the potential of a digital transition in catalysis research. Then, a summary of the current status in terms of data infrastructure in heterogeneous catalysis is presented, defining the various types of (meta-) data, from catalyst synthesis to functional analysis. Finally, an already implemented working concept for local data acquisition and storage is introduced and the benefits and further development directions for catalysis data use and sharing are discussed.

The use of nonhuman animals in research has long been a source of bioethical and scientific debate. We consider the oversight and use of nonhuman animals in chimeric research. We conducted interviews with twelve members of embryonic stem cell research oversight committees, nine members of institutional animal care and use committees, and fourteen scientists involved in human-nonhuman-animal chimeric research in different areas of the United States. Interviews addressed animal welfare and conceptual issues associated with moral status and humanization of nonhuman animals that contain human cells. Our findings suggest that concepts of enhanced moral status and consciousness are not very useful in human-nonhuman-animal chimeric research in part because their meanings are not easily defined, which presents challenges to applying the concepts in research. Instead, scientists and oversight committee members we interviewed seemed to rely on standard assessments of changes in animal welfare when focusing on the ethics of human-animal chimeric research.

A strong solid Lewis acid catalyst has been successfully obtained by modifying a known procedure of fluorinating γ-aluminium oxide, which was pre-calcined under vacuum. Calcination under vacuum at 700 °C followed by gas phase fluorination with CHClF2 led to various high-surface area materials. The structure and morphology of the catalysts was studied by P-XRD, N2 physisorption and MAS NMR spectroscopy. Their acidic sites were characterized by CD3CN adsorption and DRIFT spectroscopy as well as NH3 TPD measurements. The catalysts exhibit a moderate number of acidic sites, which however possess a very strong Lewis acidic character, and are remarkably active in catalysis, when compared to other fluorinated alumina phases known. They mediate in the presence of a silane with 1-fluoropentane dehydrofluorination reactions, isomerize 1,2-dibromohexafluoropropane and promote dismutation of CHClF2 at room temperature. This outstanding reactivity classifies these novel catalysts as strong solid Lewis acids, comparable with aluminium chlorofluoride or high-surface aluminium fluoride.

In the past decade, there has been an acceleration in genomic research, its applications, and its translation into healthcare products and services for the benefit of public health. These advances are critical to realizing the potential of genomic research for facilitating improved health and disease prevention, diagnosis, and treatment. Despite its tremendous opportunities, the dynamic and increasingly global landscape of genomic research commercialization has been accompanied by a variety of ethical challenges and concerns. The potential for unauthorized use of DNA samples from African people to develop a DNA chip amplifies discussion on the meanings, implications, and impacts of commercialization, benefit sharing, and appropriate consent in genomic research. Leadership of the Human Heredity and Health in Africa (H3Africa) Consortium convened a panel of experts to review research ethics practices employed in H3Africa Consortium projects and make recommendations regarding commercialization. Eighteen investigators submitted documents for projects involving data sharing and use of genetic information. A total of 39 informed consent documents associated with the 18 projects were reviewed. All 18 projects specified that samples would be used in future research. Less than half of the projects included language noting that samples could be used in drug or product development, that DNA samples would not be sold, and that profits would not be shared with participants. Four projects referred to commercialization. Analysis of information included in consent documents contributed to the development of a Commercialization Typology. The Typology identifies factors to consider regarding acceptability of particular instances of commercialization. DNA samples for translational research in product development require a transparent commercialization framework to inform the consent process.

As human genomics research in Africa continues to generate large amounts of data, ethical issues arise regarding how actionable genetic information is shared with research participants. The Human Heredity and Health in Africa Consortium (H3Africa) Ethics and Community Engagement Working group acknowledged the need for such guidance, identified key issues and principles relevant to genomics research in Africa and developed a practical guideline for consideration of feeding back individual genetic results of health importance in African research projects. This included a decision flowchart, providing a logical framework to assist in decision-making and planning for human genomics research projects. Although presented in the context of the H3Africa Consortium, we believe the principles described, and the decision flowchart presented here is applicable more broadly in African genomics research.

Aluminium chlorofluoride (ACF, AlClxF3-x, x = 0.05-0.3) and high-surface aluminium fluoride (HS-AlF3) were tested as heterogeneous catalysts for the reactivity towards 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), which is a potent greenhouse gas. Selective activation and dehydrofluorination of the C F bond was observed, under remarkable conditions, such as mild temperatures (70 °C) and without the need for a hydrogen source as a driving force. Consecutive reactions were developed by using C6D6 as a solvent or adding Et3SiH. Thus, the production of the dehydrofluorination product 2-chloro-3,3,3-trifluoropropene (HFO-1233xf) can be coupled to a hydroarylation or hydrodefluorination reaction in one-pot procedures.

A niobium doped high surface aluminium fluoride (HS-AlF3) catalyst was prepared, using an approach in which niobium doped aluminium hydroxide fluoride obtained via reaction of aqueous HF with the respective metal alkoxides in isopropanol is further fluorinated under flow of CHClF2 at 200 °C. A comparable procedure was used to synthesize a Nb-free variant for comparison. Both catalysts exhibit very strong Lewis acidic surface sites which are capable to activate strong carbon-halogen bonds at room temperature, just as the classical high-surface AlF3 (HS-AlF3), obtained by reacting aluminium isopropoxide with anhydrous HF, does. The catalysts were characterized by elemental analysis, P-XRD, MAS NMR spectroscopy, N2 adsorption, NH3-TPD, and pyridine photoacoustic FT-IR spectroscopy. In contrast to previously reported niobium doped HS-AlF3, which was prepared using anhydrous HF, the doped catalyst obtained via this aqueous HF-route shows excellent performance both in the isomerization of 1,2-dibromohexafluoropropane, a reaction that occurs only in the presence of the strongest Lewis acids, and in the cyclization of citronellal to isopulegol, a reaction which requires both, Lewis and Brønsted acid sites.

A series of acid catalysts were prepared, using niobium and antimony as dopants in the fluorolytic sol–gel synthesis of high surface aluminium fluoride. These new catalysts exhibit remarkable reactivity: they are able to isomerize compounds containing carbon–halogen bonds at room temperature by C–F, C–Cl and C–Br activation and perform the isomerization of double bonds and Friedel–Crafts-like reactions that are required for the cyclization of citronellal, for which the conversions increase by doping with Nb up to 99%. Furthermore, the characterization of the catalysts by means of MAS NMR, NH3-TPD, py-PAS and N2 adsorption is presented.

The health benefits of eating more plant-based foods and less meat are scientifically proven. This chapter examines the evidence in relation to common health and medical conditions, such as cardiovascular diseases, type 2 diabetes, cancers, mental health, and dementia. It also analyzes the issues related to gastrointestinal health and diet in light of the presence of fiber and other plant materials. Although the environmental benefits of a plant-based diet are well-established, there are some concerns about the ability of such food choices to supply essential nutrients to the human body, such as protein, iron, vitamin B12, and Omega 3 fatty acids. They are discussed within the framework of a healthy diet. Some of the disadvantages of diets rich on animal proteins, such as heme iron, are highlighted with a warning that the consumption of lab-grown meat may carry similar risks. A balanced plant-rich diet seems a better and easier choice.

Aluminium chlorofluoride (ACF) and high-surface aluminium fluoride (HS-AlF3) were analyzed by a set of characterization methods to assess their acidic properties: NH3-TPD, CO adsorption followed by DRIFTS, CD3CN-PAS-FTIR and MAS NMR spectroscopy after 15N-pyridine adsorption. Both catalysts contain very strong and medium-strong Lewis acid sites as confirmed by CO adsorption, in which small differences arise from the morphological properties of each catalyst, with ACF being microporous and HS-AlF3 mesoporous. Shifts of the CO vibration band of up to 77 cm−1 were observed, which account for very strong Lewis acid sites. In addition, very strong Lewis acid sites could be identified by CD3CN-PAS for both catalysts, exhibiting a shift of 95 cm−1 from free nitrile, the highest ever reported for a solid Lewis acid.

Aluminium chlorofluoride (ACF) and high-surface aluminium fluoride (HS-AlF3) were analyzed by a set of characterization methods to assess their acidic properties: NH3-TPD, CO adsorption followed by DRIFTS, CD3CN-PAS-FTIR and MAS NMR spectroscopy after 15N-pyridine adsorption. Both catalysts contain very strong and medium-strong Lewis acid sites as confirmed by CO adsorption, in which small differences arise from the morphological properties of each catalyst, with ACF being microporous and HS-AlF3 mesoporous. Shifts of the CO vibration band of up to 77 cm-1 were observed, which account for very strong Lewis acid sites. In addition, very strong Lewis acid sites could be identified by CD3CN-PAS for both catalysts, exhibiting a shift of 95 cm-1 from free nitrile, the highest ever reported for a solid Lewis acid.

The completion rate of advance directives by older African Americans remains low. This pilot study evaluated attitudes related to African Americans and advance directives and the effectiveness of the Five Wishes Education Protocol to increase completion rates. The researchers used a descriptive, cross-sectional pilot study and convenience sampling. Three group sessions were conducted over a 2-month period at three senior centers. Twenty-two older African Americans participated. The mean total score on the attitude survey indicated that participants were moderately positive towards advance directives. Following the intervention, the completion rate of the advance directive Five Wishes was 77.35% (n=17), and 54.5% (n=12) of the participants provided copies of the Five Wishes advance directives to their healthcare providers.

Here, we document for the first time the presence of the 26S proteasome and the ubiquitin pathway in a protozoan parasite that is in an early branch in the eukaryotic lineage. The 26S proteasome of Trypanosoma cruzi epimastigotes was identified as a high molecular weight complex (1400 kDa) with an ATP-dependent chymotrypsin-like activity against the substrate Suc-LLVY-Amc. This activity was inhibited by proteasome inhibitors and showed same electrophorectic migration pattern as yeast 26S proteasome in nondenaturating gels. About 30 proteins in a range of 25-110 kDa were detected in the purified T. cruzi 26S proteasome. Antibodies raised against the AAA family of ATPases from eukaryotic 26S proteasome and the T. cruzi 20S core specifically recognized components of T. cruzi 26S. To confirm the biological role of 26S in this primitive eukaryotic parasite, we analyzed the participation of the ubiquitin (Ub)-proteasome system in protein degradation during the time of parasite remodeling. Protein turnover in trypomastigotes was proteasome and ATP-dependent and was enhanced during the transformation of the parasites into amastigotes. If 20S proteasome activity is inhibited, ubiquitinated proteins accumulate in the parasites. As expected from the profound morphological changes that occur during transformation, cytoskeletal proteins associated with the flagellum are targets of the ubiquitin-proteasome pathway.

Malaria infection is initiated when an infected anopheline mosquito injects sporozoites during a bloodmeal. After injection, sporozoites enter the circulation and rapidly invade hepatocytes [1], where they develop into exoerythrocytic forms (EEF). There is a large body of evidence (reviewed in [2]) suggesting that sporozoite arrest in the liver is mediated by the binding of the parasite’s major surface protein, the circumsporozoite protein (CS; [3]), to heparan sulfate proteoglycans (HSPGs) on the hepatocyte surface. CS binding to HSPGs is mediated by region II-plus, a highly conserved stretch of amino acids, containing a motif of basic and hydrophobic residues, which binds to the negatively-charged sulfate moieties of HSPG glycosaminoglycan (GAG) chains. Physiologic ligands for these hepatic HSPGs include chylomicron and very low density lipoprotein remnants [4]. Like Plasmodium sporozoites, these lipoprotein remnants are rapidly cleared from the circulation by the liver. Clearance of these lipoproteins is mediated by apolipoprotein (apo) E which, like CS, binds to HSPGs. We have previously shown, that remnant lipoproteins can competitively inhibit sporozoite invasion of HepG2 cells in vitro and can decrease sporozoite infectivity in vivo, suggesting that sporozoites and remnant lipoproteins compete for the same HSPG binding sites at the cell surface [5]. After their sequestration from the plasma, by hepatic HSPGs [6], remnant lipoproteins are internalized by one of two receptors found on the hepatocyte surface, the LDL receptor (LDLR) and the LDL receptor-related protein (LRP) [7– * Corresponding author. Tel.: +1-212-263-6818; fax: +1212-263-8116. E-mail address: photini.sinnis@med.nyu.edu (P. Sinnis)

The importance of political competence as a new strategy for managing complexity and stress by mediators is discussed. The link between political and social/emotional competencies and the need to develop political competence into a mediation practice are highlighted.

This article explores the neglected dimensions of informed consent. In such documents as the that govern clinical research, it is explicitly stated that informed consent is a process, not a form to be signed. However, virtually all research on informed consent has proceeded as if informed consent is an event similar to a Miranda warning. The authors review what is known about the process of informed consent and ask what questions must be explored if the dynamics of the clinical decision-making process are to be better understood. Their investigation takes place in two parts. First, the authors survey what is known or not known about the effect and influence of two major parties to the decision-making process (ie, support groups in which the subject participates and the subject's primary care physician). Second, they focus on the cultural and demographic factors that contribute to the subject's identity. Although they do not propose that informed consent must become a complicated and burdensome process, they stress that understanding the process in any meaningful way will mean that one must understand these various influences to get beyond the voluminous, but often facile, research that has characterized work on informed consent.

We have recently shown that C5b-6 binds to the erythrocyte membrane via an ionic interaction with sialic acid before the addition of C7 and subsequent membrane insertion. In this study we assessed the role of anionic lipids in the binding of the terminal complement proteins to the membrane and the efficiency of subsequent hemolysis. Human erythrocytes were modified by insertion of dipalmitoyl phosphatidylcholine (DPPC), dipalmitoyl phosphatidylserine (DPPS), dipalmitoyl phosphatidylethanolamine (DPPE), or dipalmitoyl phosphatidic acid (DPPA). Lipid incorporation and the hemolytic assays were done in the presence of 100 μmol/L sodium orthovanadate to prevent enzymatic redistribution of lipid. We found that the neutral lipids, DPPC and DPPE, did not affect C5b-7 uptake or hemolysis by C5b-9. In contrast, the two acidic phospholipids, DPPS and DPPA, caused a dose-dependent increase in both lysis and C5b-7 uptake. We conclude that the presence of anionic lipids on the exterior face of the membrane increases C5b-7 uptake and subsequent hemolysis. It is known that sickle cell erythrocytes have increased exposure of phosphatidylserine on their external face and are abnormally sensitive to lysis by C5b-9. The data presented here provide a plausible mechanism for this increased sensitivity.

In recent years a number of studies have been carried out to try to understand why some people are successful in life and others are not. Psychologists have investigated the lack of positive correlation between IQ and success at work and in personal relationships. The brightest and the best do not always succeed, so how can we predict who will succeed and make the best choices about people and jobs?

8625 Introduction: We recently reported the clinical activity of IMiDs (both thalidomide (T) and lenalidomide (L)) in pts with CLL. VTE is a commonly reported complication of these agents requiring prophylaxis. Most available information is in pts treated for multiple myeloma (MM), a disease with a high baseline incidence of VTE. To determine whether the incidence of IMiDs associated VTE is similar in CLL pts we reviewed all CLL pts treated with IMiDs at our institute. Method: All CLL pts treated at our institute with T or L either alone or in combination with other antileukemic agents such as rituximab (R) or fludarabine (F)) were evaluable for this analysis. All pts were treated on IRB approved clinical trials and signed informed consent. Prophylaxis for VTE was recorded. Dose range for T was 100–300mg/day, while that of L was 5–25mg/day. Results: To date a total of 55 pts (35 on L and 20 on T) are treated with IMiDs at our center. All pts treated with L received single agent L while those treated with T received concurrent F (FT). All T treated pts also received low-dose warfarin (1 or 2 mg for body weight ≤ or > than 70 kg respectively) for VTE prophylaxis. No prophylaxis was given to L treated pts. VTE was noted in 2 (6%) pts on L and 2 (10%) on FT. Thus the cumulative incidence of IMiDs associated VTE in CLL pts at our center was 7% (4/55). Conclusion: VTE is a known side effect of IMiDs. Its incidence in CLL treated pts is unknown. Our experience with both T and L in CLL pts suggest that VTE remains a concern in this pt population as well though the incidence may be lower. Three other studies investigated T either alone (n=28)1, with F (n=18)2 or with dexamethasone/cyclophosphamide (n=3)3. Only 1 episode of VTE was reported in these studies.3 Our current analysis failed to reveal any apparent risk factors for VTE in CLL pts treated with IMiDs. Several pts on the L clinical trial continue to be on therapy. Updated results with prolonged L treatment will be presented at the meeting. 1. Kay N et al: ASH 2003 2. Furman RR et al: ASCO 2005 3. Trompeter S et al: IWCLL 2005 [Table: see text]

Introduction: Several cytokines (including TNF-alpha, IL-6 and VEGF) are reported to play a critical role in the pathogenesis of CLL cells. Targeting the tumor microenvironment through modulation of the cytokine milieu thus is a potential way to treat CLL. In 2 separate clinical studies we investigated the role of IMiDs (thalidomide and lenalidomide) either in combination with standard chemotherapy (thalidomide + fludarabine, FT) or single agent (lenalidomide, L) in pts with previously untreated or relapsed/refractory CLL, respectively. In these studies we observed tumor flare reaction not previously reported. In this report we describe the clinical characteristics of this side effect, its management and correlation with changes in serum cytokine levels. Flare Reaction (FR): CLL pts treated with IMiDs were noted to have tender increase in lymph nodes size starting within 24–48 hours of initiating therapy with or without erythema and rash. Some patients also increased their total white cell as well as absolute lymphocyte count (ALC). Results: A total of 48 pts (20 on FT and 28 on lenalidomide) are collectively treated on 2 clinical trials. Median age was------, -----had limited stage (0-II) and ----- has advance Rai stage (III, IV). ------(%) on the FT and 22 (78.5%) on the L developed a FR, which was noted as early as 24 hours after initiation of therapy (median 48 hours). Most pts resolved FR by day 14. A comparison of serum cytokine level at day 0 and 7 was done in 10 pts (9 with FR) treated with L. An increase in TNF-a (n=4), MIG (n=6), IP-10 (n=8), IL-8 (n=7) and IL-10 (n=6) was noted at day 7. Management: FR was treated with ibuprofen 400 mg q 6 hr with addition of oral morphine (or agents of equivalent potency) for improved pain control. Conclusion: FR is a new side effect noted in CLL pts treated with IMiDs that is fairly well managed by anti-inflammatory agent along with aggressive pain control. Higher incidence is noted with L. There seems to be no correlation of FR with clinical response to therapy. Identification of the FR is important to avoid confusion with disease progression. An increase in levels of inflammatory cytokine was noted in all pts treated with L which may explain the underlying mechanism of this phenomenon.

Using polyclonal and monoclonal antibodies to human recombinant IL-2 (rIL-2), we developed a sensitive radioimmunoassay (RIA) for quantitation of human IL-2. In this assay, microtitration plates pre-coated with an anti-rIL-2 monoclonal antibody (35H10), recognizing residues 59-72 of human IL-2, are incubated with serial dilutions of test samples. Captured IL-2 is quantitated by adding an affinity-purified rabbit anti-rIL-2 antibody followed by an 125I-labeled goat anti-rabbit IgG. Antibodies to chemically synthesized IL-2 peptides could replace the polyspecific rabbit anti-rIL-2 antibody as the second specific reagent in the assay. This configuration was more sensitive than others tested, approaching the level of detection of the conventional IL-2 bioassay, thus allowing detection of as little as 100-200 pg IL-2. Serum or plasma fluids, however, inhibited the assay, reducing its sensitivity by approximately 5-fold. This RIA correlated well with the conventional bioassay in measuring IL-2 levels in sera from IL-2-treated patients. This, and similar, RIAs may serve as a useful adjunct or alternative to the conventional IL-2 bioassay in detecting and quantitating human IL-2 in culture supernatants and clinical samples.

We describe a new approach to the analysis of the structural polymorphism of the DR beta, DQ alpha, and DQ beta polypeptide chains of human histocompatibility class II antigens. In comparison to conventional two-dimensional gel studies, this method provides sharper definition of the protein bands and side-by-side comparisons within the same gel, thereby permitting the detection of minor differences in the isoelectric points of the protein chains. Using this methodology we have analyzed the IEF polymorphism and the variability in the number of the DR beta chains encoded by different DR haplotypes. Twenty DR beta chain variants, which include the products of no less than two separate DR beta loci, have been thus far identified. Alleles at one of these loci are assumed to code for DR beta chains carrying the DR alloespecificities DR1, DR2, DR3, DR4, DR5, DRw6, DR7, and DR8. Alleles at a second DR beta locus encode DR beta chains that may be shared by serologically DR-different haplotypes and carry supertypic serologic specificities (i.e., DRw52 and DRw53). We also demonstrate here that the structural polymorphisms of the DQ alpha and DQ beta chains are more extensive than previously thought, report the characterization of 14 DQ beta variants, and define their relationship to the previously described DQw serologic specificities. In addition, we describe the class II haplotype associations observed for the different DR and DQ variants characterized.

To investigate the visual-memory ability of children referred for psychological evaluations of academic and/or behavior problems, 135 children were administered the Bender-Gestalt and then asked to reproduce as many designs from memory as they could. Analysis indicated that the number of designs recalled increased with age and Performance IQ but not Full Scale IQ. Results were discussed in terms of the importance of considering developmental level when evaluating children and the establishment of rough cut-off scores on recall of the Bender-Gestalt designs.

The distribution of glucuronic acid-and-sulfate-containing carbohydrate (GSC) epitope recognized by two monoclonal antibodies, HNK-1 and 4F4, was studied by immunocytochemistry in adult mouse brain. Both antibodies recognized proteins ranging in molecular weight from 60 to above 250 kDa in Western blot but no glycolipid was recognized in the adult brain. With both light and electron microscopic study, two patterns of staining are observed: diffuse neuropil staining, and individual neuronal somata staining. The diffuse neuropil staining is concentrated in discrete anatomically defined areas. At the EM level, this immunoreactivity is associated with numerous dendrites or astrocytic processes. At cell somata, most of neurons are stained only at Golgi apparatus (type 2); however, a distinct population of cells showed membranous staining (type 1) as well. Type 1 membranous immunoreactivity is observed only in membrane adjacent to astrocytic processes. In the cerebral cortex, type 1 neurons are found in layers III and V-VIa of somatosensory cortex, but only in layers V-VIa in most other cortical fields. Other areas containing type 1 neurons include the globus pallidus, the thalamic reticular nucleus, the hippocampus, the deep cerebellar nuclei, and a majority of the primary sensory and motor nuclei in the brainstem. The subpopulation of type 1 neurons show an overlap in distribution and morphology with some GABA-containing cells.

Xavier shares at least six characteristics with other developing institutions. some of which are not shared by all: private small, predominantly black, liberal arts-oriented, church-related, and serving a large percentage of disadvantaged students. Difficulties in launching and maintaining a computer science program at such an institution are not rooted in any one of these alone but rather in the complex, often apparently conflicting, cross currents of philosophies represented by these characteristics. Serving the needs of disadvantaged students in a liberal arts milieu is difficult enough, and once you establish computer science in this picture, you still have to meet the challenge of staffing with permanent, full-time faculty to effect continuity. It has been evident at Xavier from the beginning (1968) that without a strong computer science curriculum the ability to serve other departments would be severely limited; its experience bears this out. We have no great success story to tell, but we have experience to relate and some ideas for the future.

The human class II HLA-DP molecules are heterodimers of a 34–36,000 d polypeptide (DPα-chain) noncovalently associated to a 28–29,000 d polypeptide (DPβ-chain) with both the DPα and DPβ chains being encoded by genes located in the most centromeric region of the human major histocompatibility complex (MHC) (1–3). DP molecules, as the other class II molecules DR and DQ, can act as restriction elements for T-cell recognition of foreign antigens (4) and represent important histocompatibility antigens. Although the genetic polymorphism of the DP molecules can be shown by the use of serologic and cellular reagents (5,6), the precise biochemical characterization of the different polymorphic variants has been made difficult by the low levels of expression of these molecules and by their extensive microheterogeneity, particularly that of the DPβ chain. We report here on results of the biochemical analysis of the DPα and DPβ products in 137 individuals from 25 multiplex insulin-dependent diabetes mellitus (IDDM) families which allowed for the direct observation by segregation of the DP molecules encoded by 94 haplotypes. Two DPα and 7 DPβ isoelectric focusing (IEF) variants were characterized. Haplotypic associations between the DP IEF-variants and those of the DR and DQ loci were encountered which suggest a way to discriminate between high and low IDDM risk among otherwise indistinguishable HLA haplotypes.