092 Brain amylin accumulation in Parkinson’s disease is not driven by type 2 diabetes mellitus

Introduction

Type 2 diabetes (T2D) is increasingly recognised as being a risk factor for Parkinson’s disease (PD). One proposed mechanism is an interaction between amylin, a highly amyloidogenic pancre- atic hormone, and α-synuclein. Amylin accelerates α-synuclein aggregation in vitro and interacts with α-synuclein in the locus coeruleus, and neuronal, extracellular and vessel-associated amylin deposits have been reported in Alzheimer’s disease and control brains. However, the molecular link between amylin and PD and the role of T2D remains unclear.

Methods

The burden of amylin accumulation in post mortem anterior cingulate and frontal gyrus tissue from PD and non-neurodegenerative control cases, with and without T2D, was investigated using immu- nohistochemistry and western immunoblotting.

Results

Immunohistochemistry revealed very infrequent amylin labelling of senile plaques and neurofibril- lary tangles along with rare perivascular amylin deposits in PD and control brains, irrespective of T2D status. Although western immunoblotting revealed significantly increased amylin levels in PD cases compared to controls, there was no difference between diabetic and non-diabetic cases.

Conclusion

Our results do not support the hypothesis that brain amylin accumulation is increased by T2D. Higher amylin levels in PD may result from blood-brain barrier dysfunction but further studies are needed to clarify the relevance to PD pathogenesis.

Reply to 'Impulse control disorders are associated with lower ventral striatum dopamine D3 receptor availability in Parkinson's disease: A [11C]-PHNO PET study.'

Pagano and collaborators have recently reported lower ventral striatum D3 receptor availability in Parkinson's disease using PET scan. Our group conducted the first postmortem study of individuals with PD who had ICD and related behaviours in life and reported lower alpha-synuclein pathology and D3R levels in the nucleus accumbens of such individuals. The findings by Pagano and co-authors of low D3R binding in PD patients at baseline, when taken together with our findings of lower Lewy pathology and D3R in the nucleus accumbens, favour the hypothesis that D3R levels are downregulated because of excessive synaptic dopamine.

Lower nucleus accumbens α-synuclein load and D3 receptor levels in Parkinson's disease with impulsive compulsive behaviours

Impulsive compulsive behaviours in Parkinson's disease have been linked to increased dopaminergic release in the ventral striatum and excessive stimulation of dopamine D3 receptors. Thirty-one patients with impulsive compulsive behaviours and Parkinson's disease who donated their brains to the Queen Square Brain Bank for Neurological Disorders were assessed for α-synuclein neuropathological load and tyrosine hydroxylase levels in the nucleus accumbens, dorsal putamen and caudate using immunohistochemistry. Dopamine D2 and dopamine D3 receptors protein levels in the nucleus accumbens, frontal cortex and putamen were determined using western blotting. Results were compared to 29 Parkinson's disease cases without impulsive compulsive behaviours matched by age, sex, disease duration, age at Parkinson's disease onset and disease duration. The majority of patients with impulsive compulsive behaviours had dopamine dysregulation syndrome. Patients with Parkinson's disease and impulsive compulsive behaviours had lower α-synuclein load and dopamine D3 receptor levels in the nucleus accumbens. No differences were seen between groups in the other brain areas and in the analysis of tyrosine hydroxylase and dopamine D2 receptor levels. Lower α-synuclein load in the nucleus accumbens of individuals with Parkinson's disease and impulsive compulsive behaviours was confirmed on western blotting. Downregulation of the dopamine D3 receptor levels may have occurred either as a consequence of the degenerative process or of a pre-morbid trait. The lower levels of α-synuclein may have contributed to an excessive stimulation of the ventral striatum resulting in impulsive compulsive behaviours.

Pre-clinical characterisation of E2814, a high-affinity antibody targeting the microtubule-binding repeat domain of tau for passive immunotherapy in Alzheimer's disease

Tau deposition in the brain is a pathological hallmark of many neurodegenerative disorders, including Alzheimer's disease (AD). During the course of these tauopathies, tau spreads throughout the brain via synaptically-connected pathways. Such propagation of pathology is thought to be mediated by tau species ("seeds") containing the microtubule binding region (MTBR) composed of either three repeat (3R) or four repeat (4R) isoforms. The tau MTBR also forms the core of the neuropathological filaments identified in AD brain and other tauopathies. Multiple approaches are being taken to limit tau pathology, including immunotherapy with anti-tau antibodies. Given its key structural role within fibrils, specifically targetting the MTBR with a therapeutic antibody to inhibit tau seeding and aggregation may be a promising strategy to provide disease-modifying treatment for AD and other tauopathies. Therefore, a monoclonal antibody generating campaign was initiated with focus on the MTBR. Herein we describe the pre-clinical generation and characterisation of E2814, a humanised, high affinity, IgG1 antibody recognising the tau MTBR. E2814 and its murine precursor, 7G6, as revealed by epitope mapping, are antibodies bi-epitopic for 4R and mono-epitopic for 3R tau isoforms because they bind to sequence motif HVPGG. Functionally, both antibodies inhibited tau aggregation in vitro. They also immunodepleted a variety of MTBR-containing tau protein species. In an in vivo model of tau seeding and transmission, attenuation of deposition of sarkosyl-insoluble tau in brain could also be observed in response to antibody treatment. In AD brain, E2814 bound different types of tau filaments as shown by immunogold labelling and recognised pathological tau structures by immunohistochemical staining. Tau fragments containing HVPGG epitopes were also found to be elevated in AD brain compared to PSP or control. Taken together, the data reported here have led to E2814 being proposed for clinical development.

Combined fused in sarcoma-positive (FUS+) basophilic inclusion body disease and atypical tauopathy presenting with an amyotrophic lateral sclerosis/motor neurone disease (ALS/MND)-plus phenotype

AIMS

Amyotrophic lateral sclerosis/motor neurone disease (ALS/MND) is characterized by the presence of inclusions containing TDP-43 within motor neurones. In rare cases, ALS/MND may be associated with inclusions containing other proteins, such as fused in sarcoma (FUS), while motor system pathology may rarely be a feature of other neurodegenerative disorders. We here have investigated the association of FUS and tau pathology.

METHODS

We report a case with an ALS/MND-plus clinical syndrome which pathologically demonstrated both FUS pathology and an atypical tauopathy.

RESULTS

Clinical motor involvement was predominantly present in the upper motor neurone, and was accompanied by extrapyramidal features and sensory involvement, but with only minimal cognitive impairment. The presentation was sporadic and gene mutation screening was negative. Post mortem study demonstrated inclusions positive for FUS, including basophilic inclusion bodies. This was associated with 4R-tauopathy, largely as non-fibrillary diffuse phospho-tau in neurones, with granulovacuolar degeneration in a more restricted distribution. Double-staining revealed that neurones contained both types of protein pathology.

CONCLUSION

FUS-positive basophilic inclusion body disease is a rare cause of ALS/MND, but in this case was associated with an unusual atypical tauopathy. The coexistence of two such rare neuropathologies raises the question of a pathogenic interaction.

AV-65, a novel Wnt/β-catenin signal inhibitor, successfully suppresses progression of multiple myeloma in a mouse model

Multiple myeloma (MM) is a malignant neoplasm of plasma cells. Although new molecular targeting agents against MM have been developed based on the better understanding of the underlying pathogenesis, MM still remains an incurable disease. We previously demonstrated that β-catenin, a downstream effector in the Wnt pathway, is a potential target in MM using RNA interference in an in vivo experimental mouse model. In this study, we have screened a library of more than 100 000 small-molecule chemical compounds for novel Wnt/β-catenin signaling inhibitors using a high-throughput transcriptional screening technology. We identified AV-65, which diminished β-catenin protein levels and T-cell factor transcriptional activity. AV-65 then decreased c-myc, cyclin D1 and survivin expression, resulting in the inhibition of MM cell proliferation through the apoptotic pathway. AV-65 treatment prolonged the survival of MM-bearing mice. These findings indicate that this compound represents a novel and attractive therapeutic agent against MM. This study also illustrates the potential of high-throughput transcriptional screening to identify candidates for anticancer drug discovery.

Clinical and cellular effects of hypothermia, acidosis and coagulopathy in major injury

BACKGROUND

Hypothermia, acidosis and coagulopathy have long been considered critical combinations after severe injury. The aim of this review was to give a clinical update on this triad in severely injured patients.

METHODS

A non-systematic literature search on hypothermia, acidosis and coagulopathy after major injury was undertaken, with a focus on clinical data from the past 5 years.

RESULTS

Hypothermia (less than 35 °C) is reported in 1·6-13·3 per cent of injured patients. The occurrence of acidosis is difficult to estimate, but usually follows other physiological disturbances. Trauma-induced coagulopathy (TIC) has both endogenous and exogenous components. Endogenous acute traumatic coagulopathy is associated with shock and hypoperfusion. Exogenous effects of dilution from fluid resuscitation and consumption through bleeding and loss of coagulation factors further add to TIC. TIC is present in 10-34 per cent of injured patients, depending on injury severity, acidosis, hypothermia and hypoperfusion. More expedient detection of coagulopathy is needed. Thromboelastography may be a useful point-of-care measurement. Management of TIC is controversial, with conflicting reports on blood component therapy in terms of both outcome and ratios of blood products to other fluids, particularly in the context of civilian trauma.

CONCLUSION

The triad of hypothermia, acidosis and coagulopathy after severe trauma appears to be fairly rare but does carry a poor prognosis. Future research should define modes of early detection and targeted therapy.

Cognitive dysfunction and health-related quality of life after a cardiac arrest and therapeutic hypothermia

BACKGROUND

Evidence-based treatment protocols including therapeutic hypothermia have increased hospital survival to over 50% in unconscious out-of-hospital cardiac arrest survivors. In this study we estimated the incidence of cognitive dysfunctions in a group of cardiac arrest survivors with a high functional outcome treated with therapeutic hypothermia. Secondarily, we assessed the cardiac arrest group's level of cognitive performance in each tested cognitive domain and investigated the relationship between cognitive function and age, time since cardiac arrest and health-related quality of life (HRQOL).

METHODS

We included 26 patients 13-28 months after a cardiac arrest. All patients were scored using the Cerebral Performance Category scale (CPC) and Mini-Mental State Examination (MMSE). Twenty-five of the patients were tested for cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB). These patients were tested using four cognitive tests: Motor Screening Test, Delayed Matching to Sample, Stockings of Cambridge and Paired Associate Learning from CANTAB. All patients filled in the Short Form-36 for the assessment of HRQOL.

RESULTS

Thirteen of 25 (52%) patients were classified as having a cognitive dysfunction. Compared with the reference population, there was no difference in the performance in motor function and delayed memory but there were significant differences in executive function and episodic memory. We found no associations between cognitive function and age, time since cardiac arrest or HRQOL.

CONCLUSION

Half of the patients had a cognitive dysfunction with reduced performance on executive function and episodic memory, indicating frontal and temporal lobe affection, respectively. Reduced performance did not affect HRQOL.

Impact of the post-World War II generation on intensive care needs in Norway

BACKGROUND

A high birth rate during the first two decades following World War II has increased the proportion of elderly people in present-day society and, consequently, the demand for health-care services. The impact on intensive care services may become dramatic because the age distribution of critically ill patients is skewed towards the elderly. We have used registry data and population statistics to forecast the demand for intensive care services in Norway up until the year 2025.

METHODS

Data collected by the Norwegian intensive care registry (NIR), showing the age distribution in Norwegian intensive care units (ICU) during the years 2006 and 2007, were used with three different Norwegian prognostic models of population growth for the years 2008-2025 to compute the expected increase in intensive care unit bed-days (ICU bed-days).

RESULTS

The elderly were overrepresented in Norwegian ICUs in 2006-2007, with patients from 60 to 79 years of age occupying 44% of ICU bed-days. Population growth from 2008 to 2025 was estimated to be from 11.1 to 26.4%, depending on the model used. Growth will be much larger in the age group 60-79 years. Other factors kept unchanged, this will result in an increase in the need for intensive care (ICU bed-days) of between 26.1 and 36.9%.

CONCLUSION

The demand for intensive care beds will increase markedly in Norwegian hospitals in the near future. This will have serious implications for the planning of infrastructure, education of health care personnel, as well as financing of our health care system.

A comparison of SAPS II and SAPS 3 in a Norwegian intensive care unit population

BACKGROUND

Simplified Acute Physiology Score (SAPS II) is the most widely used general severity scoring system in European intensive care medicine. Because its performance has been questioned in several external validation studies, SAPS 3 was recently released. To our knowledge, there are no published validation studies of SAPS II or SAPS 3 in the Scandinavian countries. We aimed to evaluate and compare the performance of SAPS II and SAPS 3 in a Norwegian intensive care unit (ICU) population.

METHOD

Prospectively collected data from adult patients admitted to two general ICUs at two different hospitals in Norway were used. Probability of mortality was calculated using the SAPS 3 global equation (SAPS 3 G), the SAPS 3 Northern European equation (SAPS 3 NE), and the original SAPS II equation. Performance was assessed by the standardized mortality ratio (SMR), area under receiving operating characteristic, and the Hosmer and Lemeshow goodness-of-fit C test.

RESULTS

One thousand eight hundred and sixty-two patients were included after excluding readmissions, and patients who were admitted after coronary surgery or burns. The SMRs were SAPS 3 G 0.71 (0.65, 0.78), SAPS 3 NE 0.74 (0.68, 0.81), and SAPS II 0.82 (0.75, 0.91). Discrimination was good in all systems. Only the SAPS 3 equations displayed satisfactory calibration, as measured by the Hosmer-Lemeshow test.

CONCLUSION

The performance of SAPS 3 was satisfactory, but not markedly better than SAPS II. Both systems considerably overestimated mortality and exhibited good discrimination, but only the SAPS 3 equations showed satisfactory calibration. Customization of these equations based on a larger cohort is recommended.

Severity scoring in the ICU: a review

BACKGROUND

Patients in the intensive care unit (ICU) require huge resources because of the dysfunction of several of their vital organs. The heterogeneity and complexity of the ICU patient have generated interest in systems able to measure severity of illness as a method of predicting outcome, comparing quality-of-care and stratification for clinical trials.

METHODS

By searching Medline and EMBASE for publications describing scoring systems in the ICU, the most frequently used systems, defined as resulting in more than 50 references, are included in this review. Scoring systems belong to one of four classes prognostic, single-organ failure, trauma scores and organ dysfunction (OD). The different systems are described and discussed.

RESULTS

Three different prognostic scoring systems, including several versions, four single OD scores and three OD scores, were included in this review.

CONCLUSION

Different forms of scoring systems are frequently used in the ICU. They have become a necessary tool to describe ICU populations and to explain differences in mortality. As there are several pitfalls related to the interpretation of the numbers supplied by the systems, they should not be used without knowledge on the science of severity scoring.

Pure akinesia with gait freezing: a third clinical phenotype of progressive supranuclear palsy

The clinical syndrome of pure akinesia has most often been associated with progressive supranuclear palsy (PSP) and is characterized by difficulty initiating gait and "freezing" during walking, writing and speaking. Similar syndromes have been described under the rubrics of primary progressive freezing gait and primary gait ignition failure. We investigated the specificity of the clinical syndrome of pure akinesia with gait freezing (PAGF) for PSP-tau pathology. Among 749 patients archived at the QSBB, only 7 fulfilled proposed diagnostic criteria of: gradual onset of freezing of gait or speech; absent limb rigidity and tremor; no sustained response to levodopa; and no dementia or ophthalmoplegia in the first 5 years of disease. In these cases detailed pathological examination was performed. PSP was the pathological diagnosis in six patients, and Parkinson's disease (PD) in the seventh. As defined, this syndrome had a positive predictive value of 86% for PSP-tau pathology. In the cases with PSP there were no additional features of coexistent vascular or PD and the median PSP-tau score was 3, reflecting relative mild tau load. The clinical syndrome of PAGF appears to have a high specificity for PSP-tau pathology. This relatively uncommon presentation of PSP-tau pathology has less severe tau accumulation than in the more common, "classic" PSP clinical phenotype: Richardson's disease.

Frontotemporal lobar degeneration and ubiquitin immunohistochemistry

We set out to determine the frequency of the different pathologies underlying frontotemporal degeneration (FTD) in our brain bank series, by reviewing all cases of pathologically diagnosed FTD over the last 12 years. We identified and reviewed 29 cases of FTD and classified them using the most recent consensus criteria with further histological analysis of 6 initially unclassifiable cases. Detailed histological analysis of these 6 cases revealed variable numbers of ubiquitin-positive (tau and alpha-synuclein-negative) inclusions in 5 cases, consistent with the diagnosis of frontotemporal lobar degeneration with ubiquitin-only-immunoreactive neuronal changes (FTLD-U). As a consequence of the current re-evaluation, 18 (62%) of the 29 cases with FTD have underlying pathology consistent with FTLD-U. Therefore in our brain bank series of frontotemporal degeneration, most cases were non-tauopathies with FTLD-U accounting for 62% of all the diagnoses.

Occurrence of NKX3.1 C154T polymorphism in men with and without prostate cancer and studies of its effect on protein function

NKX3.1, a member of the NK class of homeodomain proteins, is expressed primarily in the adult prostate and has growth suppression and differentiating effects in prostate epithelial cells. A C-->T polymorphism at nucleotide 154 (NKX3.1 C154T) is present in approximately 11% of healthy men with equal distribution among whites and blacks. In a cohort of 1253 prostate cancer patients and age-matched controls, the presence of the polymorphism was associated with a 1.8-fold risk of having stage C or D prostate cancer or Gleason score > or =7 (confidence interval, 1.01-3.22). The NKX3.1 C154T polymorphism codes for a variant protein that contains an arginine-to-cysteine substitution at amino acid 52 (R52C) adjacent to a protein kinase C phosphorylation site at serine 48. Substitution of cysteine for arginine 52 or of alanine for serine 48 (S48A) reduced phosphorylation at serine 48 in vitro and in vivo. Phosphorylation of wild-type NKX3.1, but not of NKX3.1 R52C or NKX3.1 S48A, diminished binding in vitro to a high-affinity DNA binding sequence. NKX3.1 also serves as a transcriptional coactivator of serum response factor. Treatment of cells with 12-O-tetradecanoylphorbol-13-acetate to phosphorylate NKX3.1 had no effect on NKX3.1 coactivation of serum response factor. Neither the R52C nor the S48A substitution affected serum response factor coactivation by NKX3.1 We conclude that the polymorphic NKX3.1 allele codes for a variant protein with altered DNA binding activity that may affect prostate cancer risk.

Immunohistochemical localization of metallothionein in benign and malignant epithelial ovarian tumors

Metallothioneins (MTs) are a group of low-molecular-weight proteins that are overexpressed in a variety of human neoplasms and are related to differentiation and prognosis in some tumor types. This study investigated immunohistochemically detectable metallothionein expression in benign and malignant ovarian surface epithelial tumors of serous, mucinous, and endometrioid types. MT expression was observed in 56% of carcinomas (n = 139) and in 2% of benign neoplasms (n = 81). Of the malignant tumors, MT expression was found in 68% of endometrioid, 56% of mucinous, and 52% of serous neoplasms. There was increased MT expression in grade 3 carcinomas (64%) as compared with grade 2 (60%) and grade 1 (23%). The overexpression of MT in malignant as opposed to benign ovarian surface epithelial tumors may suggest a role in tumorigenesis. Analogous to the situation in endometrial carcinomas, there is a tendency toward higher expression in poorly differentiated tumors. Whether high MT expression is an independent prognostic factor and increased expression indicates chemotherapy resistance in ovarian cancer, as has been previously suggested, should be determined by further studies.

Immunohistochemical localization of metallothionein in benign and malignant epithelial ovarian tumors

Abstract.

McCluggage WG, Strand K, Abdulkadir A. Immunohistochemical localization of metallothionein in benign and malignant epithelial ovarian tumors.

Metallothioneins (MTs) are a group of low-molecular-weight proteins that are overexpressed in a variety of human neoplasms and are related to differentiation and prognosis in some tumor types. This study investigated immunohistochemically detectable metallothionein expression in benign and malignant ovarian surface epithelial tumors of serous, mucinous, and endometrioid types. MT expression was observed in 56% of carcinomas (n = 139) and in 2% of benign neoplasms (n = 81). Of the malignant tumors, MT expression was found in 68% of endometrioid, 56% of mucinous, and 52% of serous neoplasms. There was increased MT expression in grade 3 carcinomas (64%) as compared with grade 2 (60%) and grade 1 (23%). The overexpression of MT in malignant as opposed to benign ovarian surface epithelial tumors may suggest a role in tumorigenesis. Analogous to the situation in endometrial carcinomas, there is a tendency toward higher expression in poorly differentiated tumors. Whether high MT expression is an independent prognostic factor and increased expression indicates chemotherapy resistance in ovarian cancer, as has been previously suggested, should be determined by further studies.

Cooperative hemoglobins: conserved fold, diverse quaternary assemblies and allosteric mechanisms

Assembly of hemoglobin subunits into cooperative complexes produces a remarkable variety of architectures, ranging in oligomeric state from dimers to complexes containing 144 hemoglobin subunits. Diverse stereochemical mechanisms for modulating ligand affinity through intersubunit interactions have been revealed from studies of three distinct hemoglobin assemblages. This mechanistic diversity, which occurs between assemblies of subunits that have the same fold, provides insight into the range of regulatory strategies that are available to protein molecules.

Oncostatin M promotes biphasic tissue factor expression in smooth muscle cells: evidence for Erk-1/2 activation

Tissue factor (TF), a transmembrane glycoprotein, initiates the extrinsic coagulation cascade. TF is known to play a major role in mediating thrombosis and thrombotic episodes associated with the progression of atherosclerosis. Macrophages at inflammatory sites, such as atherosclerotic lesions, release numerous cytokines that are capable of modulating TF expression. This study examined the role of oncostatin M (OSM), a macrophage/ T-lymphocyte-restricted cytokine, in the expression of TF in vascular smooth muscle cells (SMCs). It is reported here that OSM stimulated a biphasic and sustained pattern of TF messenger RNA (mRNA). The effect of OSM on TF mRNA expression was regulated at the transcriptional level as determined by nuclear run-offs and transient transfection of a TF promoter-reporter gene construct. OSM-induced TF expression was regulated primarily by the transcription factor NF-kappaB. Activation of NF-kappaB by OSM did not require IkappaB-alpha degradation. Inhibition of MEK activity by U0126 prevented OSM-induced TF expression by suppressing NF-kappaB DNA binding activity as determined by gel-shift analysis. Further, inhibition of Erk-1/2 protein by antisense treatment resulted in suppression of TF mRNA expression, indicating a role for Erk-1/2 in modulating NF-kappaB DNA binding activity. These studies suggest that the induced expression of TF by OSM is primarily through the activation of NF-kappaB and that activation of NF-kappaB is regulated in part by the MEK/Erk-1/2 signal transduction pathway. This study indicates that OSM may play a key role in promoting TF expression in SMCs within atherosclerotic lesions.

Induction of the urokinase plasminogen activator system by oncostatin M promotes endothelial migration

Oncostatin M (OSM) is an inflammatory cytokine produced by activated macrophages and T-lymphocytes. We have previously demonstrated that OSM-induced endothelial cell migration, unlike endothelial cell proliferation and spindle formation, is independent of basic fibroblast growth factor expression (Wijelath et al. [1997] J. Cell. Sci. 110:871-879). To better understand the mechanism of OSM-induced endothelial cell migration, this study examined the potential role of the plasminogen activator system in promoting OSM mediated endothelial cell migration. OSM stimulated increased mRNA levels of urokinase-plasminogen activator (uPA) and urokinase-plasminogen activator receptor (uPAR) in a time and dose-dependent manner. Transcriptional run-off and mRNA stability analysis demonstrated that the increase in uPA and uPAR mRNA levels was due to both increased gene transcription and mRNA stability. The increase in mRNA correlated with increased protein levels of both uPA and uPAR. This increase was reflected in elevated levels of membrane-bound plasmin activity. OSM-induced endothelial cell migration was only partially dependent on plasmin activity since incubating endothelial cells without plasminogen or, in the presence of aprotinin, resulted in suppression of endothelial cell migration, indicating that OSM promoted endothelial cell migration through both a plasmin-dependent and -independent mechanism. Our results imply a role for OSM in promoting endothelial cell migration via a plasmin-dependent pathway and a uPAR-mediated pathway. Together, these and other recent studies support a role for OSM in modulating the different phases of angiogenesis.

Structural hierarchy in erythrocruorin, the giant respiratory assemblage of annelids

Many annelids, including the earthworm Lumbricus terrestris, have giant cooperative respiratory proteins (molecular masses greater than 3.5 million Da) freely dissolved in the blood, rather than packaged in cells. These complexes, termed either erythrocruorins or hemoglobins, are assembled from many copies of both hemoglobin subunits and nonhemoglobin or "linker" subunits. In this paper, we present the crystal structure of Lumbricus erythrocruorin at 5.5-A resolution, which reveals a remarkable hierarchical organization of 144 oxygen-binding hemoglobin subunits and 36 nonhemoglobin linker subunits. The hemoglobin chains arrange in novel dodecameric substructures. Twelve trimeric linker complexes project triple-stranded helical coiled-coil "spokes" toward the center of the complex; interdigitation of these spokes appears crucial for stabilization. The resulting complex of linker chains forms a scaffold on which twelve hemoglobin dodecamers assemble. This structure specifies the unique, self-limited assemblage of a highly cooperative single molecule.

Two distinct lineages of macaque gamma herpesviruses related to the Kaposi's sarcoma associated herpesvirus

BACKGROUND

KSHV, Kaposi's sarcoma-associated herpesvirus, is a necessary cofactor for the development of Kaposi's sarcoma (KS). We have previously reported KSHV-related DNA sequences in retroperitoneal fibromatosis (RF) tissue from two species of macaque. The putative herpesvirus was called RFHV for RF-associated herpesvirus. These data suggested that KSHV is a human representative of a larger family of primate herpesviruses.

OBJECTIVE

To identify and characterize other members of a putative family of KSHV-related herpesviruses in macaques in order to obtain information on the evolutionary history of KSHV infection in humans.

STUDY DESIGN

Lymphoid tissue cells and blood leukocytes from rhesus-, cynomolgus- and pigtailed-macaques were tested for the presence of unknown herpesviruses using degenerate primer-driven PCR amplification. The sequences obtained were compared against known herpesvirus sequences.

RESULTS

We have identified new herpesvirus DNA sequences in each of the three macaque species. Sequence comparisons indicate that these new viruses are most related to each other and form a separate phylogenetic lineage within the gamma herpesviruses. Screening of PBMC from Indonesian-origin quarantine animals suggests that these viruses (MGV, macaque gamma virus) are species-specific, and highly prevalent in the wild. They are readily cultured in vivo, and share a common tissue tropism with the previously identified RFHV.

CONCLUSIONS

MGV and RFHV represent two independent introductions of an ancestral gamma herpesvirus into macaque precursors.

Differential recognition of snake venom proteins expressing specific Arg-Gly-Asp (RGD) sequence motifs by wild-type and variant integrin alphaIIbbeta3: further evidence for distinct sites of RGD ligand recognition exhibiting negative allostery

Several studies have demonstrated that the amino acid residues flanking the Arg-Gly-Asp (RGD) sequence of high-affinity ligands modulate their specificity of interaction with integrin complexes. Because of the absence of structural data for integrin complexes with bound ligand, the molecular basis for this specificity modulation remains obscure. In a previous paper [Rahman, Lu, Kakkar and Authi (1995) Biochem. J. 312, 223-232] we demonstrated that two genetically distinct venom-derived RGD proteins, kistrin and dendroaspin (both containing the sequence PRGDMP), were simple competitors, indicating the recognition of an identical binding site on the alpha(IIb)beta(3) complex. Furthermore, both kistrin and dendroaspin inhibited the binding of the disintegrin elegantin (containing the sequence ARGDNP) via a non-competitive mechanism, suggesting that the binding of elegantin to the alpha(IIb)beta(3) complex was at a remote site and down-regulated via an allosteric mechanism. Here we present further evidence for distinct RGD ligand recognition sites on the alpha(IIb)beta(3) complex that exhibit a negative allosteric relationship. A panel of well-characterized recombinant dendroaspin and elegantin derivatives were employed for this study. These recombinant molecules were constructed as glutathione S-transferase fusion proteins with either an Ala or Pro residue N-terminal to the RGD sequence in combination with either a Met or an Asn residue immediately C-terminal. Equilibrium competition experiments showed that elegantin binding to ADP-treated platelets was inhibited by derivatives Eleg. AM (ARGDMP) and Eleg. PM (PRGDMP) via an allosteric competitive mechanism, providing direct evidence that modulation of the RGD motif can alter competitive behaviour. In addition, recombinant kistrin and dendroaspin both inhibited elegantin binding via a non-competitive mechanism, confirming our previous observations. Further evidence for distinct binding sites employing an independent approach was obtained by analysing the binding of the panel of venom proteins to the functionally defective heterodimer alpha(IIb)beta(3) Ser(123)-->Ala expressed on Chinese hamster ovary cells. These studies demonstrated that simple competitors kistrin and dendroaspin bound with high affinity to the variant integrin complex. In contrast, the binding of elegantin and most significantly, recombinant Dendro. PN (PRGDNP) and Dendro. AN (ARGDNP) were abolished. These observations, taken together, are consistent with a model depicting the presence of distinct sites of RGD ligand recognition on the alpha(IIb)beta(3) complex that show the preferential recognition of specific RGD motifs. Competition experiments demonstrate a negative allosteric relationship between these RGD recognition sites.

Need for job adjustment in pregnancy. Early prediction based on work history

OBJECTIVE

To examine whether a woman's need for job adjustment in pregnancy can be predicted by a short interview on working conditions at the first prenatal visit.

DESIGN

Midwives included a semi-structured work history during the interview of unselected first prenatal visits. Their early prediction about the woman's need for job adjustment was compared with the woman's own later report of such need and the need expressed as a risk score for preterm birth based on the woman's self-reported working conditions. Data on both were collected by a questionnaire presented to the woman at about the 36th week of pregnancy.

SETTING

Seven maternity centres in Oslo, Norway, April 1993-March 1994.

SUBJECTS

160 pregnant women in paid work.

MAIN OUTCOME MEASURES

The proportion of predictions of presence (positive predictive value) or absence (negative predictive value) of need that was confirmed by the woman's later report, or the risk score.

RESULTS

The positive predictive value was 86% and the negative predictive value 50% with the woman's later report as reference, and 56 and 79%, respectively, with the risk score for preterm birth as reference.

CONCLUSION

The work history allows early prediction of need for job adjustment in pregnancy.

Work pace control and pregnancy health in a population-based sample of employed women in Norway

OBJECTIVES

This study explored the possible effects of power to control one's own work pace on pregnancy health.

METHODS

Questionnaires were sent to all parturients in Norway between 16 October and 26 November 1989 for completion prior to discharge from the hospital; 87.2% responded. The study population comprised 3321 respondents with singleton pregnancies and paid work beyond the 3rd month of pregnancy. Power to control work pace was measured as self-reported influence on breaks and work pace and absence of external pacing. Pregnancy health was defined by the prevalence of preeclampsia, disabling posterior pelvic pain, low-back pain, and birthweight of <2500 g for the offspring.

RESULTS

Pregnancy health improved with increasing power to control work pace, both in manual and nonmanual work. The risk decreased with increasing control for all 4 outcomes, but the impact on birthweight was restricted to nullipara. After adjustment for age, parity, education, smoking, and manual work, the decreasing trend remained significant for preeclampsia and low birthweight of the first born. In a comparison with women with the highest level of control, the adjusted odds ratios for women with no control were 1.6 [95% confidence interval (95% CI) 0.9-3.1] for preeclampsia, 1.6 (95% CI 1.0-2.4) for disabling posterior pelvic pain, 1.3 (95% CI 1.0-1.8) for low-back pain, and 2.5 (95% CI 0.9-6.8) for low birthweight (nullipara).

CONCLUSIONS

Women with power to control their own work pace had better pregnancy health than women without such power. The results suggest increased individual control over work pace as a prime target for job adjustment during pregnancy.

Strenuous working conditions and birthweight, Norway 1989

OBJECTIVE

To examine whether strenuous working conditions in pregnancy are associated with reduced birthweight.

METHOD

Cross-sectional, population based study. Retrospective data collection by questionnaire to parturients in all maternity wards in Norway 16.10-26.11.89, completed before discharge from hospital, with response rate 87.2%. The study population consists of the 5388 women with singleton births, of whom 3321 were in paid work beyond the third month of pregnancy. Main outcome measures are prevalence of birthweight <2500 grams (LBW) and mean birthweight.

RESULTS

Strenuous working conditions increased risk of LBW, but only for nullipara, particularly non-smoking nullipara. Odds ratios with 95% confidence intervals for non-smoking nullipara, adjusted for age, education and income, were 0.3 (0.1,0.9) for influence on work pace, 2.8 (1.2,6.5) for exposure to heavy lifting and 2.2 (0.8,5.8) for twisting/bending. Four groups of occupations were defined according to exposure, solely based on reports from mothers with non-LBW children in order to avoid recall bias. Prevalence of LBW increased from 0.8% in the least exposed to 8.3% in the most exposed group. (Test for trend: p<0.05, after adjustment for age, education and income.) Strenuous working conditions had no independent effect on mean birthweight after adjustment for age, education, income and smoking.

CONCLUSION

Strenuous work increased the risk of LBW in nulliparae, particularly in non-smokers. Lack of influence on work pace was the strongest risk factor. The preventive effect of job modification in pregnancy may parallel smoking cessation.

Job adjustment as a means to reduce sickness absence during pregnancy

OBJECTIVES

This study examined the effect of job adjustment on sickness absence during pregnancy and also determined the conditions under which such adjustments are obtained.

METHODS

Data were derived from a nationally representative survey on work conditions during pregnancy in Norway in 1989. For employees (N = 2713) remaining in the same job throughout pregnancy, the percentage of women on sick leave immediately before delivery was determined according to the need for job adjustment and the obtainment of job adjustment. Those obtaining job adjustment were grouped according to workplace size, labor-market sector, co-worker gender, educational level, work schedules, weekly workhours, children under 16 years of age in the household, and age.

RESULTS

All told, 1691 women (62.3%) needed job adjustment, among whom 936 (55.4%) obtained such adjustment. The proportions of those on sick leave before delivery were 45.2% for "no need", 67.9% for "need - adjustment obtained", and 79.2% for "need - adjustment not obtained". In the last category, the difference (versus "adjustment obtained") constituted 44.5% of the weeks lost because of sickness absence in the last half of pregnancy. The odds ratio (OR) for obtaining job adjustment was larger for workplaces with more than 50 employees (OR 1.4) and smaller for jobs with work schedules other than daytime or shift work (OR 0.5) and also for women living with children under 16 years of age (OR 0.8).

CONCLUSIONS

Job adjustment is associated with reduced sickness absence during pregnancy. Further studies should explore workplace characteristics that make it difficult to obtain such adjustments, as required by law.

Work load, job control and risk of leaving work by sickness certification before delivery, Norway 1989

Sickness absence in pregnancy has been shown to be associated with strenuous working conditions and parity. So far, few studies have made adjustments for possible interaction and confounding. Such adjustments are needed to more precisely identify targets for preventive measures. We have, therefore, in a representative population of pregnant employees in Norway 1989, computed adjusted odds ratios for leaving work by sickness absence more than three (LSC > 3) and eight (LSC > 8) weeks before delivery according to working conditions identified as risk factors in earlier studies; adjusted for job control, domestic conditions and sickness absence the year prior to pregnancy. The cumulative percentage of LSC > 8 and LSC > 3 was 26.4 and 51.1. Ergonomically strenuous postures and heavy lifting increased the risk of both outcomes. In addition, shift work and hectic work pace increased the risk of LSC > 3. Influence on breaks reduced risk. Only para experienced reduced risk of LSC when working part-time. Sicklisting the year prior to pregnancy had no confounding effect, which suggest that pregnancy represents a new incompatibility with work. Preventive measures should address work postures and heavy lifting, as well as conditions influencing the woman's control with her time.

Working conditions and prevalence of pre-eclampsia, Norway 1989

OBJECTIVE

To study the associations between working conditions and pre-eclampsia.

METHODS

A cross-sectional study based on questionnaires to all parturients was conducted in Norway from 16 October 1989 to 26 November 1989, with an 87.2% response rate. Of the 5388 responders with singleton pregnancies, 3321 continued in paid work beyond the 3rd month of pregnancy. Pre-eclampsia was recorded if the woman reported hospitalization for hypertension, or if proteinuria and hypertension were diagnosed more than once in the pregnancy.

RESULTS

The prevalence of pre-eclampsia was increased in work involving the lifting of heavy loads of 10-20 kg (adjusted odds ratio (OR), 1.8; 95% CI, 1.2-2.5), hectic work pace (OR, 1.4; 95% CI, 1.0-2.0, P < 0.05), work with hands above shoulder level (OR, 1.4; 95% CI, 1.0-2.2; P = 0.07) and for parous women, shift work (OR, 2.0; 95% CI, 1.1-3.6). It was reduced when the woman had an influence on work pace (OR, 0.7; 95% CI, 0.5-1.0; P = 0.07). Prevalence was also increased with daily consumption of more than four cups of coffee (OR, 1.6; 95% CI, 1.1-2.3).

CONCLUSION

Prenatal care should include assessment of working conditions, as early improvements may reduce the risk of pre-eclampsia.

Smoking in pregnancy: a way to cope with excessive workload?

OBJECTIVE

To examine if abstention from smoking in pregnancy increases with opportunities to limit workload.

DESIGN

Cross-sectional study based on self-administered questionnaires to women post partum.

SETTING

All maternity wards in Norway, 16 October-26 November 1989.

SUBJECTS

5 438 women, or 87.2% of all parturients in Norway during the study period.

MAIN OUTCOME MEASURE

The abstention fraction (AF) defined as percentage of nonsmokers in pregnancy among prepregnancy daily smokers.

RESULTS

The abstention fraction was lower for women with lack of influence on work pace, with hectic work pace, exhaustion after work or work schedules other than daytime, for women with children <16 years of age in the household, and for women in paid work with 20 hours or more of housework weekly, than for women without these conditions. Adjusted odds ratios (OR) for abstention were low for women with children <16 years both when in paid work (OR 0.4) and as housewives (OR 0.3). Women who received extra help with housework had a high abstention fraction (OR 1.6) both when in paid work and as housewives. The abstention fraction was high for women with daytime work (OR 1.5) and low with hectic work pace (OR 0.7), compared with women without these conditions.

CONCLUSION

Abstention from smoking in pregnancy increases with opportunities to limit total workload.

Fertility patterns according to occupational grouping in Norway, 1989

In the early 1990s, most pregnant women in Norway were in gainful employment. This led to increased interest in the possible consequences for reproductive health, and a growing concern for the need to accommodate the pregnancy. We have therefore investigated how accurately general fertility rates predict the number of pregnancies in the workforce. Fertility rates (FR) among employed women and standardized fertility ratios (SFR) in occupational groups were estimated on the basis of information from the Labour Market Statistics and the national survey "Pregnancy and Work", Norway, 1989. The fertility rate among employed women was 17% higher than the general fertility rate. Two occupational groups had significantly different SFRs: technical/professional workers (SFR 118) and transport/communication workers (SFR 82). In addition, differences were found for parity-specific SFRs in administrative/executive work (SFR nullipara 80, SFR para 125) and service work (SFR nullipara 114, SFR para 80). We suggest that work status and occupation should be included among the variables registered in the Medical Birth Registry of Norway, in order to facilitate routine presentations of fertility rates and pregnancy outcomes for women in paid work. The results further indicate that work-specific conditions influence first-birth fertility. This should be explored in demographic studies of the relation between women's fertility and participation in paid work.

PSYCHIATRIC NURSING in a Psychosocial Setting

The revolutionary upheaval in this nation's health care system may cause many psychiatric nurses in traditional settings to be concerned about their future role. According to the United States Department of Health and Human Services (1990), there were 66,142 psychiatric registered nurses employed in inpatient hospital settings as of 1988. The advent of managed care, decrease in entitlements, and overburdening of the health care system has again led to less accessibility to inpatient psychiatric hospitalization, and briefer stays once hospitalized. As treatment once again moves into the community, nurses may wonder what types of new programs will follow, and if they will employ psychiatric nurses. One type of community based program uses the principles of psychosocial rehabilitation. The Village Integrated Services Agency is such an organization, allowing nurses to fully use their nursing skills, but without the focus on illness and the constraints on autonomy typically experienced in hospital settings.

Concurrence of congenital ocular motor apraxia and other motor problems: an expanded syndrome

The records of all cases of congenital ocular motor apraxia diagnosed by the Ophthalmology Department at the Children's Hospital, Boston, over the past 25 years were reviewed to ascertain other problems with motor organization. There were eight boys and two girls, ranging in age from eight months to 2 1/2 years at diagnosis. Eight of the 10 had evidence of oral motor planning problems which significantly affected their speech output. Five had evidence of awkwardness or clumsiness, suggesting difficulties with gross motor organization as well. This concurrence of motor planning problems in at least two spheres, ocular motor and oral motor, suggests more general difficulties with motor organization in this syndrome. In all cases for whom data were available the ocular motor problems resolved but oral motor problems persisted.

The effects of hydraulic resistance strength training in pre-pubertal males

In order to examine the effectiveness and safety of hydraulic resistance strength training in young males, 26 pre-pubertal males (mean age = 8.2 +/- 1.3 yr) completed a 14-wk strength training study. Subjects were evaluated before and after the 14-wk experimental period for pubertal state (Tanner's sexual maturity rating, serum testosterone, and serum dihydroepiandrosterone sulfate). Effectiveness of the strength training program was determined by measuring pre-post differences in: isokinetic strength for flexion and extension at the knee and elbow joints at two speeds (30 degrees and 90 degrees X s-1) (KIN COM, Chattecx, Inc., Chattanooga, TN), flexibility, standing long jump, vertical jump, body composition parameters, maximal oxygen consumption, and creatinine phosphokinase. Safety of strength training was assessed by biphasic musculoskeletal scintigraphy before and after the program and by physician evaluation of complaints by subjects. Strength training subjects (N = 16) participated in a 45 min/session, 3 session/wk, 14-wk supervised strength training program with an attendance rate of 91.5%. Participants performed concentric work using hydraulic resistance equipment (Hydra-Fitness Industries, Belton, TX). Eccentric work was not performed. Control subjects (N = 10) did not strength train but did participate in sport activities and activities of daily living. Results indicated that strength training subjects increased isokinetic strength as a result of strength training (average concentric work/repetition increases by 18.5 to 36.6% for the eight motions tested; torque scores over the first 90% of the range of motion increases by 13.1 to 45.1% for the eight motions tested). These changes were significantly greater than changes seen in the control group (P less than 0.05). Strength training subjects also demonstrated significant improvements (as compared to control subjects) in vertical jump (+10.4%), flexibility (+8.4%), and maximal oxygen consumption [+19.4% (l X min-1), +13.8% (ml X kg X min-1)] after the experimental period. Musculoskeletal scintigraphy revealed no evidence of damage to epiphyses, bone, or muscle as a result of strength training. Only one strength training-related injury was reported (left shoulder pain, 3 strength training sessions missed). In contrast, six strength training subjects sustained injuries during activities of daily living, resulting in 47 missed strength training sessions. It was concluded that, in the short term, supervised concentric strength training using hydraulic resistance equipment is safe and effective in pre-pubertal boys.