OP0130 COMPOSITE OF RELEVANT ENDPOINTS IN SJÖGREN’S SYNDROME (CRESS): A COMPREHENSIVE TOOL FOR CLINICAL TRIALS

Background:

Several large randomised controlled trials (RCTs) in primary Sjögren’s syndrome (pSS) failed to demonstrate drug efficacy.1-4 Many of these trials used ESSDAI as primary endpoint, showing large but similar response rates in active treatment and placebo groups.1,3,4 Given the heterogeneous nature of pSS, there is need for a composite endpoint including multiple clinically relevant parameters.

Objectives:

To develop and validate the Composite of Relevant Endpoints in Sjögren’s Syndrome (CRESS).

Methods:

A multidisciplinary team of pSS experts selected clinically relevant items and measurements to include in the CRESS. Definition of response of CRESS items was based on clinical relevance, previously defined minimal clinically important improvement (MCII) and data of the single-centre ASAP-III (abatacept) trial.1 CRESS was validated in three independent RCTs: TRACTISS (rituximab) trial2, multi-centre abatacept trial3 and ETAP (tocilizumab) trial4. CRESS response rates were assessed at the primary endpoint visit of all four trials.

Results:

Five complementary items were selected to form CRESS: systemic disease activity, patient-reported symptoms, tear gland, salivary gland and serological item. Definition of response per item is presented in Table 1. Total CRESS response was defined as response on ≥3 of 5 items. Since not all trials have ocular staining score or salivary gland ultrasonography (SGUS) available, the concise CRESS (cCRESS) was developed simultaneously, leaving Schirmer’s test and unstimulated whole saliva flow for the tear and salivary gland items, respectively. In the ASAP-III trial, CRESS response rates were 24/40 (60%) for abatacept vs. 7/39 (18%) for placebo at week 24 (p<0.001).

Table 1.

CRESS items and definition of response

ItemsMeasurementsDefinition of responseSystemic disease activityClinESSDAIScore<5 (low disease activity)Patient-reported symptomsESSPRIDecrease of ≥1 point or ≥15%Tear gland*Schirmer/OSS**-If abnormal Schirmer (≤5 mm) at baseline: increase of ≥5 mm in Schirmer-Or if abnormal OSS (≥3 points) at baseline: decrease ≥2 points in OSS-Or if both Schirmer/OSS normal scores at baseline: no change to abnormal in bothSalivary gland*UWS/SGUSIncrease of ≥25% in UWS (or if score is 0 at baseline, any increase)Or decrease of ≥25% in total Hocevar score (SGUS)SerologicalRF/IgGDecrease of ≥25% in RFOr decrease of ≥10% in IgGCRESS responderResponder on ≥3 of 5 items

Ocular Staining Score (OSS), Unstimulated whole salivary flow (UWS), Salivary gland ultrasonography (SGUS), Rheumatoid factor (RF), Immunoglobuline G (IgG)

*Concise CRESS (cCRESS): CRESS without OSS and SGUS, leaving Schirmer and UWS for tear and salivary gland items, respectively

**Mean of both eyes

In the external validation trials, cCRESS response rates for TRACTISS were: 33/67 (49%) rituximab vs. 20/66 (30%) placebo at week 48 (p=0.026). CRESS response rates (without SGUS) for the multi-centre abatacept trial were: 41/92 (45%) abatacept vs. 30/95 (32%) placebo at week 24 (p=0.067). cCRESS response rates (without rheumatoid factor) for ETAP were: 10/55 (18%) tocilizumab vs. 13/55 (24%) placebo at week 24 (p=0.482) (Figure 1A-D). Compared to ESSDAI MCII of ≥3 points decrease, CRESS was able to approximately halve placebo response rates in RCTs with high baseline ESSDAI scores (>5) (Figures 1E-H).

Conclusion:

CRESS shows lower placebo response rates compared to ESSDAI MCII, which is crucial for demonstrating treatment efficacy. With the CRESS, higher response rates in abatacept and rituximab treated patients compared to placebo were found in RCTs which previously showed negative primary endpoint results. CRESS confirmed that no differences were found for almost all outcome measures between tocilizumab and placebo,4 with low response rates. The CRESS is a well-balanced, feasible, composite endpoint for use in clinical trials in pSS patients.

References:

[1]Van Nimwegen 2020;9913(19):1–11

[2]Bowman 2017;69(7):1440–50

[3]Baer (doi:218599)

[4]Felten (doi:21846)

Acknowledgements:

The authors would like to acknowledge all contributors of the included trials.

Disclosure of Interests:

Suzanne Arends: None declared, Liseth de Wolff: None declared, Jolien F. van Nimwegen Speakers bureau: Bristol Myers Squibb, Consultant of: Bristol Myers Squibb, Gwenny M. Verstappen: None declared, Jelle Vehof: None declared, Michele Bombardieri Consultant of: MedImmune, GlaxoSmithKline, Grant/research support from: MedImmune, Simon J. Bowman Consultant of: AstraZenecea/MedImmune, Bristol Myers Squibb, Celgene, Eli Lilly, Glenmark, GlaxoSmithKline, MTPharma, Novartis, Ono, Pfizer, Takeda, UCB, XTLBio, Elena Pontarini: None declared, Alan Baer Consultant of: Bristol Myers Squibb, Sanofi, VielaBio, Novartis, Marleen Nys Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Jacques-Eric Gottenberg Grant/research support from: Bristol Myers Squibb, Pfizer, Renaud FELTEN: None declared, Neelanjana Ray Shareholder of: Bristol Myers Squibb, Employee of: Bristol Myers Squibb, Arjan Vissink: None declared, Frans G.M. Kroese Speakers bureau: Bristol Myers Squibb, Roche and Janssen-Cilag, Consultant of: Bristol Myers Squibb, Grant/research support from: Unrestricted grants from Bristol Myers Squibb, Hendrika Bootsma Speakers bureau: Bristol Myers Squibb and Novartis, Consultant of: Bristol Myers Squibb, Roche, Novartis, Medimmune, Union Chimique Belge, Grant/research support from: Unrestricted grants from Bristol Myers Squibb and Roche

A Disease Control-Oriented Land Cover Land Use Map for Myanmar

Malaria is a serious infectious disease that leads to massive casualties globally. Myanmar is a key battleground for the global fight against malaria because it is where the emergence of drug-resistant malaria parasites has been documented. Controlling the spread of malaria in Myanmar thus carries global significance, because the failure to do so would lead to devastating consequences in vast areas where malaria is prevalent in tropical/subtropical regions around the world. Thanks to its wide and consistent spatial coverage, remote sensing has become increasingly used in the public health domain. Specifically, remote sensing-based land cover/land use (LCLU) maps present a powerful tool that provides critical information on population distribution and on the potential human-vector interactions interfaces on a large spatial scale. Here, we present a 30-meter LCLU map that was created specifically for the malaria control and eradication efforts in Myanmar. This bottom-up approach can be modified and customized to other vector-borne infectious diseases in Myanmar or other Southeastern Asian countries.

Malaria Exposure in Ann Township, Myanmar, as a Function of Land Cover and Land Use: Combining Satellite Earth Observations and Field Surveys

Despite progress toward malaria elimination in the Greater Mekong Subregion, challenges remain owing to the emergence of drug resistance and the persistence of focal transmission reservoirs. Malaria transmission foci in Myanmar are heterogeneous and complex, and many remaining infections are clinically silent, rendering them invisible to routine monitoring. The goal of this research is to define criteria for easy-to-implement methodologies, not reliant on routine monitoring, that can increase the efficiency of targeted malaria elimination strategies. Studies have shown relationships between malaria risk and land cover and land use (LCLU), which can be mapped using remote sensing methodologies. Here we aim to explain malaria risk as a function of LCLU for five rural villages in Myanmar's Rakhine State. Malaria prevalence and incidence data were analyzed through logistic regression with a land use survey of ~1,000 participants and a 30-m land cover map. Malaria prevalence per village ranged from 5% to 20% with the overwhelming majority of cases being subclinical. Villages with high forest cover were associated with increased risk of malaria, even for villagers who did not report visits to forests. Villagers living near croplands experienced decreased malaria risk unless they were directly engaged in farm work. Finally, land cover change (specifically, natural forest loss) appeared to be a substantial contributor to malaria risk in the region, although this was not confirmed through sensitivity analyses. Overall, this study demonstrates that remotely sensed data contextualized with field survey data can be used to inform critical targeting strategies in support of malaria elimination.

Weight of salivary gland ultrasonography compared to other items of the 2016 ACR/EULAR classification criteria for Primary Sjögren's syndrome

OBJECTIVE

Major salivary gland ultrasonography (SGUS) is widely used for the diagnosis of primary Sjögren's syndrome (pSS). Our objective was to assess the contribution of SGUS compared to other items of the 2016 ACR/EULAR pSS classification criteria, based on expert opinion.

METHODS

A secure web-based relational database was used by 24 experts from 14 countries to assess 512 realistic vignettes developed from data of patients with suspected pSS. Each vignette provided classification criteria items and information on history, clinical symptoms and SGUS findings. Each expert assessed 64 vignettes, and each vignette was assessed by 3 experts. A diagnosis of pSS was defined according to at least 2 of 3 experts. Validation was performed in the independent French DiapSS cohort of patients with suspected pSS.

RESULTS

A criteria-based pSS diagnosis and SGUS findings were independently associated with an expert diagnosis of pSS (P < 0.001). The derived diagnostic weights of individual items in the 2016 ACR/EULAR criteria including SGUS were as follows: anti-SSA, 3; focus score ≥ 1, 3; SGUS score ≥ 2, 1; positive Schirmer's test, 1; dry mouth, 1; and salivary flow rate < 0.1 mL/min, 1. The corrected C statistic area under the curve for the new weighted score was 0.96. Adding SGUS improves the sensitivity from 90.2 % to 95.6% with a quite similar specificity 84.1% versus 82.6%. Results were similar in the DiapSS cohort: adding SGUS improves the sensitivity from 87% to 93%.

CONCLUSION

SGUS had similar weight compared to minor items, and its addition improves the performance of the 2016 ACR/EULAR classification criteria.

Randomized clinical trial of elective resection versus observation in diverticulitis with extraluminal air or abscess initially managed conservatively

Background

The aim of this RCT was to determine whether elective resection following successful non-operative management of a first episode of acute sigmoid diverticulitis complicated by extraluminal air with or without abscess is superior to observation in terms of recurrence rates.

Methods

This was a single-centre, sequential design RCT. Patients were randomized to elective surgery or observation following non-operative management and colonoscopy. Non-operative management included nil by mouth, intravenous fluids, intravenous antibiotics, CT with intravenous contrast on arrival at hospital, and repeat CT with intravenous and rectal contrast on day 3 in hospital. The primary endpoint was recurrent diverticulitis at 24 months. Patients with a history of sigmoid diverticulitis, immunosuppression or peritonitis were not included.

Results

Of 137 screened patients, 107 were assigned randomly to elective surgery (26) or observation (81), and underwent the allocated intervention after successful non-operative management. Conservative management failed in 15 patients. Groups were similar in age, sex, BMI, co-morbidities and colorectal POSSUM. Rates of recurrent diverticulitis differed significantly in the elective surgery and observation groups (8 versus 32 per cent; P = 0·019) at a mean(s.d.) follow-up of 37·8(8·6) and 35·2(9·2) months respectively. There was also a significant difference in time to recurrence (median 11 versus 7 months; P = 0·015). A total of 28 patients presented with recurrent diverticulitis complicated by extraluminal air and/or abscess (2 elective surgery, 26 observation), all of whom recovered with repeat non-operative management.

Conclusion

The majority of patients observed following conservative management of diverticulitis with local extraluminal air do not require elective surgery. Registration number: NCT01986686 (http://www.clinicaltrials.gov).

Basic steps to building a research program

Establishing a clinical trial infrastructure is an important step when developing a successful research program. Two areas required for success include financial oversight and a qualified research team.

Autotaxin (NPP-2) in the brain: cell type-specific expression and regulation during development and after neurotrauma

Autotaxin is a secreted cell motility-stimulating exo-phosphodiesterase with lysophospholipase D activity that generates bioactive lysophosphatidic acid. Lysophosphatidic acid has been implicated in various neural cell functions such as neurite remodeling, demyelination, survival and inhibition of axon growth. Here, we report on the in vivo expression of autotaxin in the brain during development and following neurotrauma. We found that autotaxin is expressed in the proliferating subventricular and choroid plexus epithelium during embryonic development. After birth, autotaxin is mainly found in white matter areas in the central nervous system. In the adult brain, autotaxin is solely expressed in leptomeningeal cells and oligodendrocyte precursor cells. Following neurotrauma, autotaxin is strongly up-regulated in reactive astrocytes adjacent to the lesion. The present study revealed the cellular distribution of autotaxin in the developing and lesioned brain and implies a function of autotaxin in oligodendrocyte precursor cells and brain injuries.

Molecular signature of CD34+ hematopoietic stem and progenitor cells of patients with CML in chronic phase

In this study, we provide a molecular signature of highly enriched CD34+ cells from bone marrow of untreated patients with chronic myelogenous leukemia (CML) in chronic phase in comparison with normal CD34+ cells using microarrays covering 8746 genes. Expression data reflected several BCR-ABL-induced effects in primary CML progenitors, such as transcriptional activation of the classical mitogen-activated protein kinase pathway and the phosphoinositide-3 kinase/AKT pathway as well as downregulation of the proapoptotic gene IRF8. Moreover, novel transcriptional changes in comparison with normal CD34+ cells were identified. These include upregulation of genes involved in the transforming growth factorbeta pathway, fetal hemoglobin genes, leptin receptor, sorcin, tissue inhibitor of metalloproteinase 1, the neuroepithelial cell transforming gene 1 and downregulation of selenoprotein P. Additionally, genes associated with early hematopoietic stem cells (HSC) and leukemogenesis such as HoxA9 and MEIS1 were transcriptionally activated. Differential expression of differentiation-associated genes suggested an altered composition of the CD34+ cell population in CML. This was confirmed by subset analyses of chronic phase CML CD34+ cells showing an increase of the proportion of megakaryocyte-erythroid progenitors, whereas the proportion of HSC and granulocyte-macrophage progenitors was decreased in CML. In conclusion, our results give novel insights into the biology of CML and could provide the basis for identification of new therapeutic targets.

Uptake and trafficking of DNA in keratinocytes: evidence for DNA-binding proteins

The skin is an interesting organ for human gene therapy due to accessibility, immunologic potential and synthesis capabilities. In this study, we attempted to visualize and measure the uptake of naked FITC-labeled plasmid by FACS analysis detecting up to 15% internalization in a dose- and time-dependent manner. Cycloheximide treatment inhibited the uptake by >90%, suggesting a protein-mediated uptake. The inhibition of different internalization pathways demonstrated that blocking macropinocytosis (by amiloride and N,N-dimethylamylorid) reduced DNA uptake by >85%, while the inhibition of clathrin-coated pits (by chlorpromazine) and caveolae (by nystatin/filipin III) did not limit the uptake. Colocalization studies using confocal laser microscopy revealed a time-dependent accumulation of plasmid DNA in endosomes and lysosomes. When a green fluorescent protein (GFP) expression vector was used, specific GFP-RNA became detectable by reverse transcriptase-PCR, whereas measurable amounts of protein could not be identified in FACS experiments. To detect the potential DNA receptors on the keratinocyte surface, membrane proteins were extracted and subjected to South-Western blotting using digoxigenin-labeled calf thymus and lambda-phage DNA. Two DNA-binding proteins, ezrin and moesin, known as plasma membrane-actin linkers, were identified by one- and two-dimensional-South-Western blots and matrix-assisted laser desorption and ionization-mass spectrometry. Ezrin and moesin are functionally associated with a number of transmembrane receptors such as the EGF, CD44 or ICAM-1 receptor. Taken together, naked plasmid DNA seems to enter human keratinocytes through different pathways, mainly by macropinocytosis. Two DNA-binding proteins were identified that seemed to be involved in binding/trafficking of internalized DNA.

Functional characterization of transgene integration patterns by halo fluorescence in situ hybridization: electroporation versus retroviral infection

Gene transfer techniques are essential for bioengineering and gene therapy. Retroviral vectors constitute an important tool in this context as integrase-catalyzed genomic anchoring is one of the best defined results of nonhomologous recombination, occurring at loci with favorable expression properties. On the basis of a retroviral expression cassette, this study focuses on differences regarding the genomic targets after its transfer by either retroviral infection or electroporation. Fluorescence in situ hybridization (FISH) of clones generated by infection revealed for the majority an association of the transgene with the nuclear matrix while this was true only for a minority of single copy clones if the same construct was transferred by electroporation. Our results demonstrate that the process of integration is distinct for both gene transfer routes and confirm that retroviral survival strategies favor integration next to scaffold/matrix attachment regions. These results may be one key to explain recent consequences of gene therapy trials that have led to the deregulation of endogenous genes.

Targeting CD19 with genetically modified EBV-specific human T lymphocytes

Human Epstein-Barr virus-specific T cells were genetically modified to express chimeric receptors specific for human CD19, which is expressed on the cell surface of most B cell malignancies. The receptor-modified EBV-specific T cells can be expanded and maintained long term in the presence of EBV-infected B cells. They recognize autologous EBV-infected targets through their conventional T cell receptor, and allogeneic EBV-infected targets and tumor targets through their chimeric receptor. They efficiently lyse both EBV and CD19-positive tumor targets in the absence of background cytotoxicity against CD19-negative targets. Donor-derived EBV-specific T cells expressing chimeric anti-tumor receptors may represent a source of effector cells that could be safely administered to leukemia patients to eradicate minimal residual disease after allogeneic bone marrow transplantation.

Genomic imbalances in the progression of endocrine pancreatic tumors

Endocrine pancreatic tumors (EPTs) are neoplasms with malignant potential. To explore the molecular basis of metastatic progression in human EPTs, we analyzed 17 paired specimens of primary EPTs and their metastases and 28 nonmetastatic EPTs using comparative genomic hybridization (CGH). Genomic alterations were detected in all of the matched primary/metastatic tumors and 19 (58%) nonmetastatic EPTs. The mean number of genomic changes was 17.3 in metastases, 12.5 in their primary tumors, and 4.5 in nonmetastatic EPTs. Statistical analysis of shared genomic changes in matched pairs of primary tumors and metastases showed a high probability (>95%) of a clonal relationship in 15 of the 17 cases. A closely related genetic pattern was also demonstrated on the basis of concordance analysis of the two groups. The most striking genomic changes which were enriched in metastases included gains of chromosomes 4 and 7 and losses of 21q. Other common regions of frequent losses (>40%) identified in metastases and/or their primary tumors involved 2p, 2q, 3p, 3q, 6q, 10p, and 11p, whereas frequently detected gains (>40%) in the paired tumors involved 5p, 5q, 12q, 14q, 17q, 18q, and 20q. These chromosomal aberrations were found in significantly fewer nonmetastatic EPTs. Some of these chromosomal loci may harbor genes contributing to the progression of EPT.

Spitzoid malignant melanoma with lymph-node metastasis. Is a copy-number loss on chromosome 6q a marker of malignancy?

Distinction of spitzoid malignant melanomas (SMM) from Spitz nevi may be difficult or even impossible on the basis of conventional histology. In this report, a patient suffering from a primary lesion diagnosed as a Spitz nevus and a metastatic malignant melanoma approximately 4 years thereafter is described. A diagnosis of SMM was made subsequently upon review of the primary lesion. In the present analysis, we used comparative genomic hybridization (CGH) to define markers characteristic of SMM. The primary lesion revealed deletions on chromosomes 6q and 9p. In the metastasis, additional deletions on chromosomes 10p and 10q and gains of chromosome 7 were found. To our knowledge, no chromosomal aberration on chromosome 6 was hitherto demonstrated in benign melanocytic nevi. Findings reported in the literature suggest that human melanoma metastasis suppressor gene maps to 6q. In contrast, losses on chromosome 9p seem to be an early event in the development of melanoma. However, they are not only found in melanomas but are occasionally present in Spitz nevi as well as in atypical nevi. The CGH result with deletion of 6q in this difficult to diagnose primary melanocytic lesion strongly supports the diagnosis of malignant melanoma. To demonstrate the reliability of loss on chromosome 6q as a marker of SMM, a larger number of lesions must be investigated.

Coping with kinetic and thermodynamic barriers: RMCE, an efficient strategy for the targeted integration of transgenes

Site-specific recombinases have become powerful tools for the targeted integration of transgenes into defined chromosomal loci. They have been successfully used both to achieve predictable gene expression in cell culture and for the systematic creation of transgenic animals. A recent improvement of this method, the recombinase-mediated cassette exchange procedure (RMCE), permits expression in the absence of any co-expressed selection marker gene.

Transcriptional properties of genomic transgene integration sites marked by electroporation or retroviral infection

As a possible consequence of their survival strategy, proviruses are predominantly found in transcription-promoting genomic sites. For certain applications, these findings have led to the preferential use of retroviral vectors for the stable integration of transgenes. This study demonstrates that transcription levels of single-copy proviruses, which have been established either by infection or by single-copy transfection (electroporation), are rather comparable. Therefore, electroporation is suggested as an alternative gene transfer route in cases where the use of infectious retroviral vehicles is to be avoided due to safety considerations. A difference between clones derived from these two gene transfer routes concerns the inactivation pattern which, for electroporated clones, is an exclusive property of the low expressers. This difference may be due to the nature of the illegitimate recombination event which is thought to be less invasive if catalyzed by the retroviral integrase. Substantial differences between infection and Ca phosphate-mediated transfection that have been reported earlier are explained by the respective transfection parameters.

[The sonographic picture of an echogenic liver is an indicator of pathologic glucose tolerance]

BACKGROUND

Almost all patients in departments of internal medicine routinely undergo abdominal ultrasound examination in which liver changes indicating hepatic steatosis are often detected. The aim of this study was to assess the occurrence of pathological oral glucose tolerance, manifest diabetes mellitus and other changes indicative of a metabolic syndrome in patients with sonographic signs of hepatic steatosis.

PATIENTS AND METHODS

577 patients were examined during a period of 6 months: 90 patients fulfilled the inclusion criteria.

RESULTS

Among the 90 patients with echodense liver who were included in the study (42 female, 48 male) 36 patients presented with previous diagnosis of diabetes mellitus (40%). The oral glucose tolerance test was impaired in 19 patients (21%) and in four patients with manifest diabetes mellitus (4%). Among patients with echodense liver a high percentage presented with obesity and impaired fat metabolism.

CONCLUSIONS

The large number of patients with an impaired oral glucose tolerance test converting to manifest diabetes, as well as the large number of patients with manifest disorders of fat metabolism suggest that screening for diabetes should be performed in patients who present with sonographic signs of hepatic steatosis.

Dissociative recombination of HD+ in selected vibrational quantum states

Rate coefficients for dissociative recombination of HD+ in selected vibrational states have been measured by a combination of two molecular fragment imaging methods by using the heavy-ion storage ring technique. Recombination fragment imaging yields state-to-state reaction rates. These rates are converted to rate coefficients by using vibrational level populations of the stored ion beam, derived from nuclear coordinate distributions measured on extracted ions. The results show strongly increasing rate coefficients for high vibrational excitation, where additional dissociation routes open up, in agreement with a theoretical calculation. Very low rate coefficients are found for certain, isolated vibrational states.

Erythropoietin response to anemia as a function of age

The erythropoietin (EPO) response to anemia was assessed for 244 subjects aged 1-64 years (mean 45.2 years) and 121 subjects aged 65-94 years (mean 68.3 years). Subjects included non-anemic individuals as well as those with anemia of various etiologies, excluding renal disease and pregnancy. Significant inverse correlations between serum immunoreactive EPO and hematocrit were noted for both groups. Regression lines failed to show a significantly lower slope or y-intercept for older compared to younger subjects. EPO levels were not significantly lower for older compared to younger subjects when controlled for hematocrit level. These results suggest that the EPO response to anemia in older subjects is similar to that of younger subjects.

Insulin-mediated and non-insulin-mediated metabolic effects of gastroenteropancreatic peptides in type I and type II diabetes

In this brief review of regulatory function of gastroenteropancreatic peptides in control of intermediary metabolism in normal and diabetic states, with and without mediation by insulin and/or glucagon, a variety of possible mechanisms have been described. It is apparent that the pharmacologic actions of the peptides identified in various locations provide models for multiple routes of delivery and modes of action of effectors in this control system. Examples already exist of each of the hypothetical mechanisms illustrated in the scheme in Figure 4. It is clear that a great deal of study will be necessary in identification of the active agents and assessment of their importance in the physiology of intermediary metabolism. With respect to the possible pathophysiologic roles of regulatory peptides of the gastroenteropancreatic system other than insulin and glucagon, a number of considerations of Type I and Type II diabetes have been raised. The balance of the evidence suggests that Type I diabetes may be viewed as an insulin deficiency syndrome, so that physiological replacement with insulin may be expected to result in correction of the metabolic abnormalities. Nevertheless, the difficulty of physiologic replacement treatment, which may call for portal delivery of insulin, is well recognized, and abnormalities secondary to insulin deficiency even in "well-treated" Type I diabetes may be compounded by the effects of gastroenteropancreatic peptides other than insulin, exerted through the various mechanisms discussed. In Type II diabetes mellitus, current understanding of the pathophysiology is much less complete and no convincing description of the etiology exists. The various metabolic actions of the gastroenteropancreatic peptides, and their interactions with other endocrine, paracrine and nervous regulatory mechanisms, represent a dauntingly complex control system. The elucidation of this system can provide fertile ground for the development and testing of hypotheses for the pathophysiology of disordered metabolism in Type II diabetes mellitus.

Isolation and partial characterization of ovine lactoferrin

Ovine lactoferrin was isolated by ammonium sulfate precipitation and ion exchange chromatography. Comparative analyses were performed with the bovine protein. Differences in the amino acid compositions and the tertiary structure of the proteins were observed.

Deoxyribonucleic acid polymerase from Physarum polycephalum. Properties of the major cytoplasmic activity in exponentially growing microplasmodia

DNA polymerase was purified 1000-fold from the cytoplasm of microplasmodia of the myxomycete Physarum polycephalum. The activity was found in two forms exhibiting molecular weights of 204000 and 116000 respectively. Both forms eluted together from DNA-cellulose and DEAE-Sephadex columns. The Stokes radii were 6.5 and 5.5 nm. The sedimentation coefficients were 7.6 and 5.2 S. The frictional ratios of 1.69 suggest a highly hydrated and/or an asymmetric structure of the molecule. The enzyme-catalyzed reaction was sensitive to N-ethylmaleimide (60% inhibition by 1 mM). Unlike DNA polymerase alpha from mammalian cells the Physarum enzyme was stimulated by 30 mM NaCl. Activated DNA was the preferred template. Poly(A) . (DT)12 was not accepted. The Km value for deoxynucleoside triphosphates was 3 micron, for activated DNA 50 microgram/ml and for Mg2+ at the optimum [k+] of 150 mM about 0.6 mM.

Genetic factors and malaria in the Temuan

The jungle habitat of the Temuan aborigines harbors a variety of infectious diseases, the most notable being malaria. Our study of 15 genetic systems in the Temuan revealed substantial polymorphism and within-population genetic diversity. The polymorphisms for Hb beta, G6PD, and El are of interest in regard to genetic adaptation to malaria. Among the polymorphisms investigated we conclude that G6PD deficiency and elliptocytosis are likely to have malaria-resistant effects as evidenced by their low association with malarial parasitemia or their higher frequency in adults than in children. These findings suggest that the malarial habitat of the Temuans is livable in the long range sense for them because of the cluster of malaria-resistant alleles in their gene pool (G6PD)-, El, and possibly, but not tested here because of its low frequency, Hb beta E). The same condition probably holds for the Semai, the nearest aborigine neighbors of the Temuan (although the Semai have not been tested for malarial parasitemia and for these polymorphisms simultaneously), since the Semai have substantial Hb betaE, G6PD-, and El. The Temuan have a cultural identity system of rituals, beliefs, and certain aspects of language which effectively isolates them genetically from Malays and other nonaborigines. This system hinders the dilution of the malaria-resistant alleles of the Temuan gene pool with the malaria-susceptible alleles of the nonaborigine gene pools.

Hemoglobin Constant Spring (slow-moving hemoglobin X components) and hemoglobin e in Malayan aborigines

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