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Model-based real-time scenario monitoring for transient event prediction with RAPTOR

Vitreoretinal eye surgery requires ultimate surgeon's precision and skills. Significant variation exists in the approaches between different surgeons. Procedures are often indicated as difficult to perform. The surgeon's personal skill level is considered critical, including hand motion stability and left/right hand dexterity. Precision of instrument manipulation is a key requirement and a limiting factor in such procedures. The collaboration between high-precision research at the Eindhoven University of Technology and a spin-off company PRECEYES has produced a working prototype for teleoperation robot-assistance during vitreoretinal surgery. This PRECEYES Surgical System enables the surgeon to achieve a higher level of precision and decrease the time span of procedures.

Twenty-six cases of B cell lymphoproliferative disorder (BLPD) were identified among 2395 patients following hematopoietic stem cell transplants (HSCT) for which an overall incidence of BLPD was 1.2%. The true incidence was probably higher, since 9/26 of the diagnoses were made at autopsy. No BLPD was observed following autologous HSCT, so risk factor analyses were confined to the 1542 allogeneic HSCT. Factors assessed were HLA-mismatching (> or = 1 antigen), T cell depletion (TCD), presence of acute GvHD (grades II-IV), donor type (related vs unrelated), age of recipient and donor, and underlying disease. Factors found to be statistically significant included patients transplanted for immune deficiency and CML, donor age > or = 18 years, TCD, and HLA-mismatching, with recipients of combined TCD and HLA-mismatched grafts having the highest incidence. Factors found to be statistically significant in a multiple regression analysis were TCD, donor age and immune deficiency, although 7/8 of the patients with immunodeficiencies and BLPD received a TCD graft from a haploidentical parent. The overall mortality was 92% (24/26). One patient had a spontaneous remission, but subsequently died >1 year later of chronic GVHD. Thirteen patients received therapy for BLPD. Three patients received lymphocyte infusions without response. The only patients with responses and longterm survival received alpha interferon (alphaIFN). Of seven patients treated with alphaIFN there were four responses (one partial and three complete). These data demonstrate that alphaIFN can be an effective agent against BLPD following HSCT, if a timely diagnosis is made.

For advanced motion systems there is an increasing demand for higher production throughput and accuracy. Traditionally, such systems are designed using a rigid-body design paradigm, which aims at designs with high stiffness. The alternative is to design a lightweight system and deal with the resulting flexibilities by over-actuation and over-sensing. This paper presents a data-based spatial feedforward method based on previous task trials, which aims at reducing the vibrations over the complete structure during motion. The proposed method is experimentally validated on an industrial prototype and compared to standard mass feedforward using rigid-body decoupling.

Remote maintenance will determine the available uptime of future fusion plants such as ITER. Experience at JET showed that a human- in- the- loop tele- operated approach is crucial, although this approach entails drawbacks such as the required extensive operator training and relatively long execution times. These drawbacks are common knowledge, but little quantitative research is available to guide improvements (such as improved training methods, or active operator support systems). The aim of this paper is to identify the key areas for further improvement of tele-operated maintenance for ITER. This is achieved by a detailed task analysis based on recent maintenance at JET, using task logbooks and video data as well as interviews with experienced master- slave operators. The resulting task analysis shows the (sub)tasks that were most time- consuming and shows a large variance in time performance within operators, but also substantial differences between qualified operators with different levels of experience. The operator interviews indicate that intuitive (virtual) visual feedback and artificial (guiding) forces are promising directions for improvement. The results found in this study will be used for future research and development activities focusing on haptic guiding strategies, with the aim to further design and optimize RH maintenance systems for ITER and beyond.

Intravenous immunoglobulins (IVIg) purified by cold ethanol fractionation have a very good safety record with regard to the transmission of many viruses. However, a few cases of non-A-non-B hepatitis have been described after intravenous injection of some immunoglobulin preparations. To ensure even higher safety for our IVIg, an additional virus inactivation step, based on pasteurization, was developed. The heating of aqueous IVIg was performed without stabilizer, and at a very low salt concentration (< 1 mM) at acidic pH. No generation of polymer was detected after pasteurization and a significant decrease in the proportion of dimers was observed. Analysis of the secondary structure by circular dichroism showed a very slight change in the secondary structure. The biological properties of the Fc region as well as the Fab region were not affected by the pasteurization. Our method has several advantages: (1) improvement of viral safety; (2) there is no need to add stabilizer which may stabilize viral particles, and (3) the absence of any hypotensive effect and low anticomplementary activity indicates a good clinical tolerance of IgG preparation.

A highly purified preparation of human plasma factor VIIa was submitted to chromogenic assays with S-2288 factors IXa, Xa, activated protein C and thrombin being absent. Factor VIIa alone or in the presence of calcium, kept its activity even in the presence of high concentrations of aprotinin, inhibition appeared only in the presence of a factor VIIa-tissue factor complex. A two-stage amidolytic assay using activation of purified factor X and hydrolysis of S-2765 chromogenic substrate by the generated Xa was used to show a competitive inhibition with a Ki value of 30 microM. Aprotinin had no effect on factor Xa amidolytic activity per se. The factor VIIa-tissue factor complex could be adsorbed to immobilized aprotinin and removed by a chaotropic ion like KSCN 3 M. The assays with the DFP inactivated VIIa-tissue factor complex proved that the interaction involved the active site of factor VIIa. The inhibition of the VIIa-tissue factor complex was demonstrated in a clotting assay using aprotinin enriched normal or factor VIII deficient plasma.

For more than three decades there has been speculation regarding a possible role of zoonotic diseases in the development of human leukemia. This study investigated the potential relationship between exposure to pets and the development of childhood leukemia.Data from 2359 cases of acute leukemia from two large case-control studies were analyzed. Cases were individually matched to population controls on telephone exchange, age, and race. Conditional logistic regression was used to estimate odds ratios (OR) associated with pet ownership.Overall, there was no association between pet ownership (either "any pet", dog, or cat) and childhood acute leukemia (OR(any pet:) = 1.01, 95% CI 0.89-1.2). Additionally, no relationship was found between exposure to an ill pet and childhood leukemia.The results of this analysis suggest that pet ownership (healthy or sick) is unrelated to an increased risk of childhood leukemia.

Studies of the relation between parental smoking and childhood leukemia have produced inconsistent results. In the largest case-control studies of childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) conducted to date, the authors evaluated leukemia risk relative to parental self-report of cigarette smoking.In telephone interviews in which a structured questionnaire was used, parents of 1842 ALL patients, 517 AML patients, and their matched controls were asked about their cigarette smoking habits before, during, and after the pregnancy with the index child. Risk of leukemia was examined by histologic type, age of the child at diagnosis, immunophenotype (for ALL), and French-American-British morphology group (for AML).The risk of ALL was not associated with the father's ever having smoked (odds ratio [OR] = 1.04, 95% confidence interval [CI] 0.90-1.20) or the mother's ever having smoked (OR = 1.04, 95% CI 0.91-1.19). Similarly, no significant risk of AML was observed for paternal (OR = 0.88, 95% CI 0.67-1.16) or maternal smoking (OR = 0.95, 95% CI 0.74-1.22). The relative risk of leukemia was not significantly different from the null for parental smoking in any time period during or around the index pregnancy, nor was it related to the number of cigarettes, the number of years of smoking, or the number of pack-years. A small number of sporadic, statistically significant associations were found, but overall there appeared to be no association between parental cigarette smoking and ALL or AML, or any subgroup of leukemia.Parental smoking while pregnant or exposure to cigarette smoke shortly after birth is unlikely to contribute substantially to the risk of childhood leukemia in North America.

Archival slides are a potentially useful source of DNA for mutation analyses in large population-based studies. However, it is unknown whether specimen age or histological stains alter the accuracy of Taq polymerase or induce secondary mutations in sample DNA. To address this question, we evaluated five methods for extraction of genomic DNA from archival bone marrow slides of 17 leukemia patients and analyzed exons 1 and 2 of the N- and K-ras genes for the presence of mutations. Of the five methods, optimal DNA purification was achieved by boiling and phenol:chloroform extraction. N-and K-ras exons 1 and 2 were independently amplified using 35 cycles of PCR, and 6-12 clones for each exon were isolated and individually sequenced for each patient. Mutations were confirmed by repeat extraction, cloning, and sequencing. Sixteen of 17 patient samples were successfully amplified (94%), including slides up to 29 years old. Twelve slides had been stained with Wright-Giemsa, I stained with toluidine blue, and 4 were unstained. A total of 16 single-base mutations were identified of 33,840 nucleotides sequenced. No insertions or deletions were identified. Six of 16 single-base mutations were previously described activating mutations in codon 13 of N-ras exon 1. The 10 other mutations were in other regions of the N- and K-ras genes and were not reproduced after repeat extraction, cloning, and sequencing. The frequency of these other alterations was I of 3384 bp. This value is comparable with the inherent error frequency for Taq polymerase. Our findings suggest that high fidelity DNA amplification can be achieved using archival hematological slides as old as 29 years and can be reliably used in genetic analyses.

Autologous transplantation for non-Hodgkins lymphoma and Hodgkin's disease is widely used as standard therapy for those with high-risk or relapsed tumor. Peripheral blood stem cell (PBSC) collections have nearly completely replaced bone marrow stem cell (BMSC) harvests because of the perceived advantages of more rapid engraftment, less tumor contamination in the inoculum, and better survival after therapy. The advantage of PBSC, however, may derive from the hematopoietic stimulating cytokines used for PBSC mobilization. Therefore, we tested a randomized comparison of GM-CSF vs. G-CSF used to prime either BMSC or PBSC before collection for use in autologous transplantation. Sixty-two patients receiving transplants (31 PBSC; 31 BMSC) for non-Hodgkin's lymphoma (n = 51) or Hodgkin's disease (n = 11) were treated. All patients received 6 days of randomly assigned cytokine. Those with cellular marrow in morphologic remission underwent BMSC harvest, while those with hypocellular marrow or microscopic marrow tumor involvement had PBSC collected. Neutrophil recovery was similarly rapid in all groups (median 14 days; range 10-23 days), though two patients had delayed neutrophil recovery using GM-CSF primed PBSC (p = 0.01). Red cell and platelet recovery were significantly quicker after BMSC mobilized with GM-CSF or PBSC mobilized with G-CSF. This speedier hematologic recovery resulted in earlier hospital discharge as well. However, in multivariate analysis, neither the stem cell source nor randomly assigned G-CSF vs. GM-CSF was independently associated with earlier multilineage hematologic recovery or shorter hospital stay. Relapse-free survival was not independently affected by either the assigned stem cell source or the randomly assigned priming cytokine, though malignant relapse was more frequent in those assigned to PBSC (RR of relapse 3.15, p = 0.03). These data document that BMSC, when collected following cytokine priming, can yield a similarly rapid hematologic recovery and short hospital stay compared with cytokine-primed PBSC. Using primed BMSC, no difference in malignant relapse or relapse-free survival was observed. These findings suggest that despite widespread use of PBSC for transplantation, BMSC, when collected following hematopoietically stimulating cytokines, may remain a satisfactory source of stem cells for autologous transplantation. G-CSF and GM-CSF are both effective in priming autologous PBSC or BMSC for collection.

Bone marrow transplantation (BMT) can cure patients with high-risk or recurrent acute lymphoblastic leukemia (ALL). Those lacking a related donor can receive either autologous or histocompatible unrelated donor (URD) marrow. Autotransplantation may result in higher risk of relapse, whereas URD allografts, although associated with serious posttransplant toxicities, may reduce relapse risk. Six years (1987 to 1993) of consecutive autologous BMT (University of Minnesota, Dana Farber Cancer Institute; n = 214) were compared with URD transplants (National Marrow Donor Program; n = 337). Most transplants (70% autologous, 48% URD) were in early remission (first or second complete remission [CR1 or CR2]); 376 patients (75% autologous, 64% URD) were less than 18 years old. Autologous BMT led to significantly lower transplant-related mortality (TRM; relative risk [RR] 0.35; P = .001). URD transplantation offered greater protection against relapse (autologous RR 3.1; P = .001). Patients greater than 18 years old, women, and BMT recipients beyond CR2 had higher TRM, whereas adults, BMT recipients in CR2+, or BMT recipients during 1991 through 1993 had significantly more relapse. After 25 months median follow-up, 100 URD and 56 autologous recipients survive leukemia free. URD BMT in CR2 resulted in superior disease-free survival (DFS), especially for adult patients. Multivariate analysis showed superior DFS for children, men, and BMT during CR1 or 2. Autologous and URD BMT can extend survival for a minority of patients unlikely to be cured by chemotherapy, and the results with either technique are comparable. Greater toxicity and TRM after URD BMT are counterbalanced by better protection against relapse. Prospective studies addressing additional clinical variables are needed to guide clinical decision making about transplant choices for patients with ALL.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder of immune regulation leading to widespread lymphocytic and hemophagocytic infiltration of vital organs. Apparent cure has only been achieved with allogeneic bone marrow transplantation (BMT). This report describes 20 consecutive patients, who underwent either matched sibling donor (n = 4) or unrelated donor (URD; n = 16) BMT. Age at the time of BMT was 0.4 to 5.3 years (median, 0.8 years). Central nervous system disease was present at diagnosis in 13 patients. At BMT, 14 patients were in a clinical remission, whereas 6 patients had active HLH. All patients were engrafted after cytoreduction with busulfan, cyclophosphamide, and etoposide. The probability of grade II-III acute graft-versus-host disease (GVHD) for all patients was 57% (95% confidence limit [CL], 0.28, 0.86), and 73% (95% CL, 0.44, 1.0) in URD patients. The overall probability of survival at 3 years was 45% (95% CL, 0.23, 0.67) and 44% (95% CL, 0.19, 0.68) when URD BMT was evaluated separately. Favorable BMT outcome was associated with clinical remission status at the time of BMT. The preparative regimen was well tolerated, and in the 9 surviving patients it provided durable engraftment and was effective at eradicating the underlying disease.

The design logic and experimental evaluation of high-lift, low-drag, two-element, NLF airfoils are described. The main driver for this development was the improvement of the endurance performance of long-endurance aircraft with high aspect ratio wings, operating at medium and high altitudes. Structural and internal volume considerations were attended to by designing airfoils with an increased thickness ratio, while the bridging between different points in the flight envelope was achieved by exploiting the concept of variable geometry. This concept is particularly attractive for high altitude flight, because of its potential to provide a simultaneous response to aerodynamic, structural, internal volume and hinge moment requirements. C /C

We undertook an analysis of 2,150 recipients of bone marrow transplant (BMT) at the University of Minnesota to determine the incidence of post-BMT malignant neoplasms (MNs). Fifty-one patients developed 53 MNs, compared with 4.3 expected from general population rates (standardized incidence ratio [SIR], 11.6, 95% confidence interval [CI], 8.2-14.5). These included 22 occurrences of B-cell lymphoproliferative disorder (BLPD), 17 solid nonhematopoietic tumors, 10 myelodysplastic syndromes (MDS), 1 acute myelogenous leukemia (AML), 2 non-Hodgkin's lymphoma (NHL), and 1 Hodgkin's disease (HD). The estimated actuarial incidence of any post-BMT malignancy was 9.9% +/- 2.3% at 13 years posttransplant. The cumulative probability of BLPD plateaued at 1.6% +/- 0.3% by 4 years from transplant and factors independently associated with increased risk included in vitro T-cell depletion of marrow (relative risk (RR) = 11.9, P.001), HLA mismatch (RR = 8.9, P.001), use of antithymocyte globulin (ATG) for graft versus host disease (GVHD) prophylaxis (RR = 5.9, P.001) or in the preparative regimen (RR = 3.1, P = .03) and primary immunodeficiency (RR = 2.5, P = .06). The cumulative probability of developing solid malignancy was 5.6% +/- 2.2% at 13 years from BMT. Malignant melanomas were the most common (SIR, 10.3, 95% CI 1.9 to 25.4). The actuarial incidence of MDS/AML plateaued at 2.1% +/- 0.8% at 9 years and was seen most often in older patients receiving autologous peripheral blood stem cells for HD or NHL. These data document that BMT recipients are at an increased risk of later malignancy, which may add significant morbidity and mortality to the transplant process. Methods for screening and identification of individuals at increased risk need to be addressed in future studies.

Twenty-three second bone marrow transplants (BMT) were performed between October 1987 and January 1994 for patients with malignant relapse following initial BMT. For first BMT, twenty-one of 23 (91%) were conditioned with cyclophosphamide plus total body irradiation. For second BMT, a uniform conditioning regimen consisting of busulfan and cyclophosphamide was used. Eleven patients had chronic myelogenous leukemia, seven acute leukemia, four lymphoma, and one myelodysplastic syndrome. Median patient age at second BMT was 32 years, the median time between first BMT and relapse was 22 months, and the median time to second BMT after relapse was 5 months. The second BMT marrow source included: autologous marrow (1), unrelated donors (4), new matched sibling donors (5) and same matched sibling donors as the first BMT (13). The Kaplan-Meier disease-free survival and survival rates at 3 years were 38 and 43%, respectively (median follow-up of survivors was 45 and 48 months, respectively), and five patients survive disease-free at 4-6 years. Nine of the 13 deaths occurred within 100 days after second BMT; eight had relapsed within 1 year of the first BMT. We conclude that: (1) second BMT can offer durable long-term survival in certain patients, especially those who relapse late after first transplant; (2) busulfan and cyclophosphamide is a suitable conditioning regimen for second BMT.

A pasteurized preparation of fibrin glue composed of two separate stable, liquid components: highly purified human thrombin and fibrinogen concentrate is described. The components are mixed extemporaneously during application. Thrombin was prepared using a prothrombin complex concentrate as starting material which was activated by calcification and then heated in solution during 10 hours at 60 degrees C in the presence of stabilizers. The isolation of thrombin was carried out using a column of benzamidine-Sepharose 6B. The eluate contained thrombin with a high degree of purity (more than 95% assessed by SDS-PAGE) with a specific activity2,500 IU/mg protein. The purified liquid thrombin preparation remained stable for at least 6 months. The fibrinogen concentrate was prepared from cryoprecipitate after removal of factor VIII and then virally inactivated by pasteurization in the presence of glucose and sorbitol. After purification the concentrate containing a high level of fibrinogen was formulated with urea 0.5 M or arginine 5% before conditioning. Both components of the fibrin glue kept its biological properties for more than 6 months at +4 degrees C.

EBVirus-associated B cell lymphoproliferative disorder (BLPD) is a recognized complication of primary immunodeficiency and organ as well as bone marrow transplantation. Although the nature of the immune defects that predispose to the development of BLPD are unknown, it is postulated that aberrant T cell responses are involved. It is our hypothesis that unbalanced lymphokine production is a major contributory factor to abnormal B cell growth in response to EBV, resulting in BLPD. Since IFN-alpha and IL-4 are important regulators of B cell proliferation and also regulate the synthesis of IgE, we determined serum levels of IFN-alpha, IL-4, and IgE in 8 patients with newly diagnosed BLPD. Comparison was made to healthy recipients of organ transplants on immunosuppressive therapy without BLPD, and normal EBV seropositive controls. Levels of serum IL-4 were significantly elevated in both patients with BLPD as well as in healthy immunosuppressed organ transplant recipients as compared with normal healthy individuals. Patients with BLPD exhibited a combination of significantly lower levels of serum IFN-alpha, and significantly higher levels of serum IgE than either healthy EBV seropositive individuals or healthy recipients of organ transplants on immunosuppressive therapy. These results suggest that imbalance in the proportions of circulating cytokines favoring B cell proliferation may be contributing to the development of EBV-associated BLPD. The potential significance of the finding of low IFN-alpha in patients who develop BLPD is exemplified by our recent success in the treatment of BLPD with IFN-alpha and intravenous IgG.

BACKGROUND: Previous studies have demonstrated that high levels of glucocorticoid (GC) exposure are associated with increased fracture risk. However, none has reported potential cost impacts. OBJECTIVE: To estimate the marginal costs from vertebral fractures among GC patients. METHODS: Subjects 18–64 years old with different GC exposure levels, with and without fractures, were selected (n = 50,191). GC exposure was categorized into three levels: high (3+ claims of continuous use or> 9.5 prednisone-equivalent mg/day), low (other GC use), and no GC use. Fractures, comorbid conditions, and costs were determined 15 months before and up to 3.5 years after index date. Regression models were used to estimate the marginal effects of vertebral fractures on pharmacy costs, medical costs and total costs. The models controlled for age, gender, pre-index date costs, GC exposure/fracture combinations, and pre-index and new post-index date comorbid conditions. RESULTS: Vertebral fractures led to significant per-member per-month (PMPM) cost increases in each GC exposure group. Furthermore, the additional increase in marginal cost from vertebral fracture on total PMPM costs among high GC patients versus low GC patients was 83% ($170; p < 0.001). Differential increases in pharmacy and medical PMPM costs between high and low GC patients were 151% ($56; p < 0.01) and 68% ($115; p = 0.014), respectively. CONCLUSIONS: Vertebral fractures were associated with increased PMPM costs, holding constant patients' underlying conditions. High GC patients had greater PMPM increases from vertebral fractures compared to those with low or no GC exposure. These findings provide new evidence that vertebral fractures have substantial increases on treatment costs among GC patients. Also, greater PMPM increases from vertebral fractures among high GC patients versus low GC patients suggest vertebral fractures increase in severity with GC exposure. These results also support the need for adjuvant therapy to reduce fracture risk and associated morbidities.

This paper considers the design of fixed order dynamic controllers for uncertain systems. Necessary conditions are derived for the minimum of a mixed H2/H∞ performance objective. Additionally, the paper considers the problem of deriving relevant uncertainty descriptions in this H2/H∞ framework. The design method is applied to a high bandwidth control design problem for a flexible servo system with an uncertainty of the frequency of the resonance. The H2/H∞ controller has been implemented in a Digital Signal Processor. The servo behaviour shows robust performance for the considered envelope of frequencies of the resonance.

The study of the interaction between activated protein C (APC) and non-plasmatic inhibitors allowed us to demonstrate that aprotinin is a potent competitive inhibitor of APC with a Ki of 1.35 μmol/L. It was possible to adsorb immunopurified protein C (PC) activated by venom activator to insolubilized aprotinin and to recover the active enzyme after elution by HCl 0.1 Nor by a chaotropic ion, for example KSCN 3 mol/L. The interaction involved the active-site of the enzyme since PC and DIP-APC did not bind to the matrix. Thus, APC could be purified, after activation, in a one-stage procedure out of a mixture of protein such as a prothrombin complex concentrate.

Pure alpha2M is prepared with fresh plasma as starting material, to prevent the interaction of alpha2M from proteolytic enzymes of plasma such as thrombin, plasmin and kallikrein. During the purification steps, polybrene and aprotin are used as inhibitors and plasminogen is absorbed onto bentonite. When alpha 2M is submitted to polyacrylamide gel electrophoresis (PAA) containing 0.1% SDS, a complete dissociation in two half-molecules of MW 380,000 occurs. When alpha2M is incubated in 1% SDS and 1% beta-mercaptoethanol as reducing agent, only one component of MW 190,000 is observed in PAA-SDS. This experiments show that the alpha2M molecule consist of two symetric halves of same MW (380,000) linked by non covalent bonds. Each two-half-molecules is made of two polypeptides chains MW 190,000 linked by disulfide bonds. Thus alpha2M molecule contains four polypeptides chains having a same MW. The same techniques were applied to the study of alaph2M proteinases complexes. Three different proteinases (plasmin, trypsin and papain) were used in these experiments. Trypsin and papain are commercialy available. Plasminogen was obtained by affinity chromatography and activated into plasmin by insoluble streptokinase fixed on PAB cellulose.

Inter-alpha-trypsin inhibitor (I alpha I) has been purified from C.N.T.S. fraction III as starting material. The purification procedure includes D.E.A.E. cellulose chromatography and gel filtration on G 150 Sephadex in the presence of EDTA. The purified protein gives one precipitation line in immunoelectrophoresis against anti-whole human serum. It reacts only with an anti I alpha I immune serum and possesses a strong antitryptic activity. When studied in starch or polyacrylamide gel electrophoresis 2 components are observed, each of them having the same antigenic structure and the same antitryptic activity as the crude preparation. The slower and less important component is dissociated by 0,1% SDS. The molecular weight estimation of I alpha I BY PAA/SDS is about 180,000. This result is not modified by the presence of 1% beta mercaptoethanol indicating that I alpha I consists of one polypeptide chain. Crude preparation reveals under the same electrophoretical conditions small amounts of low molecular weight components (135,000 52,000 and 26,000) which can be due to a proteolytic action on I alpha I. Indeed plasmin is able to produce such fragments having an antitryptic activity as shown by fibrin/polyacrylamide gel electrophoresis. The relationship between small molecular weight inhibitors of human serum and bronchial secretions and those obtained after degradation of I alpha I by plasmin is discussed.

Resume Un dosage radio-immunologique des anticorps de classe IgG a ete mis au point et utilise pour mesurer les anticorps antipollen de graminees dans le serum humain et dans des preparations d'immunoglobulines a usage therapeutique. Dans cette methode, l'allergene est couple covalentement a un support solide et les anticorps IgG sont reveles par la proteine A, marquee a l'iode 125. Le taux des anticorps mesure dans le serum de sujets ayant subit une immunotherapie, est significativement plus eleve que dans une population temoin. Le taux des anticorps antipollen de graminees a ete mesure dans des solutions d'immunoglobulines a usage therapeutique. Ces taux sont, en moyenne, de 5 a 15 fois ceux observes dans un pool de serum pris comme reference. Lorsque ces methodes de dosage sont appliquees a des preparations d'immunoglobulines fractionnees selon un procede utilisant l'acide caprylique, des taux d'anticorps de 15 a 30 fois superieurs a ceux du serum de reference, sont obtenus.

Clq can be isolated as a by-product of large scale fractionation. The euglobulins of fraction III are submitted to chromatography on CM-cellulose in a batch-procedure. The active fraction being frequently contaminated by lysozyme the protein can be further purified by gel-filtration in the presence of carbohydrates. The purified Clq is suitable for the detection of immune complexes.

Summary The prothrombin complex is adsorbed from plasma or cryoconcentrate supernatant onto DEAE-sephadex A50. The adsorbent is washed several times with 0.21 M NaCl. The first washing proved to be a new subfraction of routine fractionation suitable as starting material for the purification of several proteins such as C1-inactivator, N-carboxypeptidase, ceruloplasmin and kallikrein.

A number of different processes clear peptides from the circulation. These will be described and illustrated using examples from a range of peptide hormones and analogues.

Antibodies directed against viruses and bacteria are not equally distributed among the main classes of immunoglobulins, e.g. IgG, IgA and IgM. It has been found that IgM is mostly concerned with certain antibacterial activities (Salmonella, Escherichia coli and Pseudomonas) and IgA with high antibody titers for poliomyelitis virus I whereas antibody activities against many viruses such as influenza and measles virus occur preferentially in the IgG population. Furthermore, isolated immunoglobulin deficiency syndromes are actually well known. In the light of these findings, new concepts of immunotherapy have developed. Massive i.v. IgG-therapy is already widely used in congenital and acquired severe hypogammaglobulinemia. Preparations enriched in IgA and IgM are needed to complete the immunotherapeutical possibilities. Such a fraction called IgGAM has already been prepared in our Institute. Fraction III obtained during large scale fractionation is used as starting material and caprylic acid for the precipitation of most proteins other than the immunoglobulins present in fraction III. The immunoglobulin concentrate is finally obtained by ethanol precipitation of the caprylic acid supernatant. The present study is concerned with various modifications of the initial technique in order to obtain fractions more specially enriched in IgA or in IgM. In some cases the standard IgGAM fraction has been submitted to a further fractionation step, such as adsorption of IgG on DEAE-cellulose or precipitation of certain immunoglobulins achieved by Rivanol or by lowering the salt concentration. In other trials the fractionation procedure starting from fraction III has been modified. Rivanol has been used as a precipitating agent for the subfractionation of fraction III. It is well known that IgG is soluble in the presence of Rivanol. This technique was thus used in order to obtain preparations enriched mainly in IgM and IgA. The precipitate obtained after the addition of Rivanol was dissociated by NaCl and the solution further subfractionated by caprylic acid. In a similar way PEG was associated with the caprylic acid precipitation step. PEG precipitates proteins mainly in function of their molecular weight. However, the enrichment of IgM of the final fraction did not exceed 32% and much IgM was lost under the experimental conditions. It proved easiest to suspend fraction III in distilled water leaving IgM in the precipitate; it is dissolved and the solution submitted to a slightly modified caprylic acid precipitation step. This fraction contains 35-40% IgM, few (2-6%) IgA and about 50% IgG whereas an IgA (35%) enriched fraction is obtained when fraction III is solubilized with acetate at pH 6.2 and then submitted to precipitation by caprylic acid under slightly modified conditions as compared with our standard IgGAM. Thus, simple modifications of the standard procedure allow to prepare fractions enriched more specially in IgM or IgA. Fractions poor or almost devoid of IgG can also be obtained...

Summary Resonance Raman spectra of ceruloplasmin using the 632.8 nm He-Ne radiation show bands at 415, 402 (shoulder), 382, 360 and 340 cm−1 which can be assigned to the metal-ligand stretching modes of the two “blue” Cu(II) ions present in the enzyme. After addition of N3− and SCN− to ceruloplasmin the Cu(II)-ligand bonds of one of the two “blue” copper sites are disrupted and three bands in the RR spectra disappear, namely, at 415, 382 and 340 cm−1. RR data enable the assignment of the metal-ligand stretching vibrations of each “blue” cupric ion, give evidence of subtle conformational changes around the non disrupted one, and confirm previous results indicating the non equivalency of the two “blue” copper sites.