Identification of factor XIII-A as a marker of alternative macrophage activation

Factor XIII subunit A of blood coagulation (FXIII-A) is known to be synthesized but not secreted by the monocyte/macrophage cell line. On the basis of its intracellular localization and substrate profile, FXIII-A is thought to be involved in certain intracellular processes. Our present study was designed to monitor the changes in FXIII-A gene expression and protein production in long-term culture of human monocytes during their differentiation into macrophages in the presence of activating agents (interleukin-4, interferon-gamma, Mycobacterium bovis BCG) inducing classical and alternative activation pathways. By using quantitative RT-PCR and fluorescent image analysis at the single-cell level we demonstrated that the expression of FXIII-A both at the mRNA as well as at the protein level is inversely regulated during the two activation programmes. Here we conclude that FXIII-A expression is an intracellular marker for alternatively activated macrophages, while its absence in monocyte-derived macrophages indicates their classically activated state.

Retinoid X receptors: X-ploring their (patho)physiological functions

Retinoid X receptor (RXR) belongs to a family of ligand-activated transcription factors that regulate many aspects of metazoan life. A class of nuclear receptors requires RXR as heterodimerization partner for their function. This places RXR in the crossroad of multiple distinct biological pathways. This and the fact that the debate on the endogenous ligand requirement for RXR is not yet settled make RXR still an enigmatic transcription factor. Here, we review some of the biology of RXR. We place RXR into the evolution of nuclear receptors, review structural details and ligands of the receptor. Then processes regulated by RXR are discussed focusing on the developmental roles deduced from studies on knockout animals and metabolic roles in diseases such as diabetes and atherosclerosis deduced from pharmacological studies. Finally, aspects of RXR's involvement in myeloid differentiation and apoptosis are summarized along with issues on RXR's suitability as a therapeutic target.

pH-sensitive fluorescent dye as probe for proton uptake in photosynthetic reaction centers

Isolated and purified reaction centers (RC) from Rhodobacter sphaeroides R-26.1 were solubilised in detergent with excess quinone and external electron donors and illuminated in the presence of pyranine. The pH change accompanying the reaction center photocycle was monitored by recording the variation of the pyranine fluorescence intensity. Using Q(B)-depleted reaction centers or blocking the photocycle with terbutryne strongly reduced the pH change. The usefulness and limits of this technique in monitoring the pH changes during the RC photocycle are also discussed.

The promoter of the mouse tissue transglutaminase gene directs tissue-specific, retinoid-regulated and apoptosis-linked expression

Tissue transglutaminase is a multifunctional enzyme that accumulates to high levels in cells undergoing apoptosis. Retinoids act as an acute and direct regulator of tissue transglutaminase gene transcription. The studies reported here were carried out to elucidate the molecular mechanisms involved in the regulation of tissue transglutaminase expression. We have isolated and characterized the mouse tissue transglutaminase gene promoter and 3.8 kb of 5'-flanking DNA. A large fragment of the promoter that includes both the core promoter and 3.8 kb of 5'-flanking DNA shows retinoid-dependent transcriptional activity when stably transfected into HeLa cells. In these stably transfected HeLa cells both the endogenous tissue transglutaminase gene and transfected mouse tissue transglutaminase promoter are activated by all-trans retinoic acid and by retinoic acid receptor (RAR)-specific and retinoid X receptor (RXR)-specific retinoids. In embryos made transgenic with a transglutaminase promoter-beta-galactosidase reporter gene, the transgene shows specific patterns of expression during limb development. The transglutaminase transgene is expressed in cartilage, the cells of the apical ectodermal ridge, and in regions of apoptotic cell death of the interdigital mesenchyme. It appears that cis-acting elements responsible for the complex retinoid regulation, tissue- and apoptosis-specific expression are embedded within the proximal 3.8 kb of DNA flanking the 5'-end of the mouse tissue transglutaminase gene.

Imaging features of pseudoaneurysms of the hand in children and adults

OBJECTIVE

Our objective was to review the imaging features of pseudoaneurysms of the hand in 25 patients. The patients presented with a mass, peripheral paresthesia, or ischemia. Pseudoaneurysm of the hand is a rare and often clinically unsuspected diagnosis. Correct diagnosis is important because there are risks for distal embolic disease with ischemia or gangrene of the fingers, ulnar or digital nerve dysfunction, rupture, or bone erosion and joint destruction. Scant reports appear in the world literature, and this report is the first review, to our knowledge, of the imaging features. The cause may be a history of a single direct trauma or chronic trauma, as seen in patients with hypothenar or thenar hammer syndrome.

CONCLUSION

Awareness of the specific imaging appearances of pseudoaneurysms of the hand and their complications may improve the accuracy of radiologic diagnosis, advance the preoperative workup, and prevent possible clinical complications such as digital gangrene, nerve dysfunction, and aneurysm rupture.

Restoration of pinch grip in ulnar nerve paralysis: extensor carpi radialis longus to adductor pollicis and abductor pollicis longus to first dorsal interosseus tendon transfers

A double tendon transfer was used to restore thumb pinch in nine consecutive patients. The extensor carpi radialis longus was transferred to the adductor pollicis tendon and one slip of the abductor pollicis longus was transferred to the first dorsal interosseus tendon. The patients were followed for 6 (range, 2-10) years and there were no instances of transfer rupture. Selective recruitment of the motors of the transfers was possible in all cases. Their amplitude was considered adequate for all the cases of adductor transfers but was limited in all of the first dorsal interosseus ones. Key pinch was 73% (range, 41-104%), the pulp-to-pulp pinch was 72% (range, 50-95%) and the power grip was 73% (range, 35-91%) of the opposite hand. The force of thumb adduction was 63% (range, 27-132%) and of index finger abduction was 58% (range, 21-104%) of the unaffected side.

The retinoid X receptor and its ligands: versatile regulators of metabolic function, cell differentiation and cell death

Retinoid X Receptors (RXRs) consist of a family of nuclear receptors that target and regulate multiple signalling pathways. The early evolutionary emergence of RXRs in comparison to other nuclear receptors may have allowed for the development of unique properties as transcriptional regulators. Indeed, the complexity of these receptors is derived from their ability to activate transcription as homodimers or as obligate heterodimeric partners of a multitude of other nuclear receptors. In addition, RXRs can regulate gene expression in a ligand-dependent (forming permissive heterodimeric complexes) or - independent (forming non-permissive heterodimeric complexes) manner. Given that ligand binding is a critical component of RXR function, this review will focus on the ligand dependent functions of RXR. The remarkably conserved ligand binding domain of RXR is a multi-functional structure that in addition to ligand binding, serves as a homo- and heterodimeric interface, and a region to bind coactivactor and corepressor molecules. RXRs have a small ligand binding pocket and therefore bind their ligands (such as 9-cis RA) with both high affinity and specificity. In the presence of ligand, permissive RXR heterodimers bind coactivators, but nonpermissive complexes can bind coactivators or corepressors depending on the activation of the RXR's heterodimeric partner. Physiologically, the temporal and tissue specific pattern of RXRs as well as the presence of phenotypic abnormalities in receptor knockout studies (most severe in RXRa -/- animals) demonstrate the important role for these receptors both during development (morphogenesis) and in adult differentiated tissues (cell proliferation, cell differentiation, cell death). These receptors also play an important regulatory role metabolic signaling pathways (glucose, fatty acid and cholesterol metabolism), including metabolic disorders such as type 2 diabetes, hyperlipidemia and atherosclerosis. RXRs function as master regulators producing diverse physiological effects through the activation of multiple nuclear receptor complexes. RXRs represent important targets for pharmacologic interventions and therapeutic applications.

Development and study of an amperometric biosensor for the in vitro measurement of low concentration of putrescine in blood

An amperometric biosensor was developed for the in vitro determination of putrescine in blood samples because elevated level of putrescine in blood can be a diagnostic indicator of certain kinds of cancer. The electrochemical transducer consisted of a flat form, three electrode amperometric micro-cell fabricated with thin film photolithography on flexible Kapton substrate. An immobilized putrescine oxidase (PUO) layer provided the biocatalytic oxidation of the putrescine, while the generated hydrogen peroxide was detected on the platinum-working electrode. An electropolymerized poly(m-phenylenediamine) (pPDA) size-exclusion layer was used to protect the working electrode from fouling and to prevent signal generation by common electroactive interferents present in blood. The preparation of the biocatalytic enzyme- and outer protective layers was optimized for improved sensitivity and response time. A detection limit of 50 nM was achieved in pH-adjusted whole blood samples, which is below pathological levels.

Coordination properties of adenosine-5'-monophosphate and related ligands towards Me2Sn(IV)2+ in aqueous solution

The coordination of Me2Sn(IV)2+ to adenosine-5'-monophosphate (AMP) and the related compounds D-ribose-5-phosphate (R5P), D-glucose-1-phosphate (G1P) and D-glucose-6-phosphate (G6P) in aqueous solution was investigated by means of potentiometric titration, and 1H-, 31P-NMR and Mössbauer spectroscopic methods in the pH range 2-11 (I=0.1 M NaClO4, 298 K). The complex of AMP and Me2Sn(IV)2+ precipitated at low pH was characterised by elemental analysis, FT-IR and Mössbauer spectroscopic methods. From a comparison of the pK values obtained in the presence and absence of metal ion and the stability constants for the different systems, the coordination of [N] is excluded, while bidentate coordination of the phosphate group is presumed. Mössbauer spectroscopic measurements recorded in the glassy state confirmed bidentate coordination of the phosphate and the formation of mixed hydroxo complexes in the weakly acidic, neutral and strongly basic pH range. With increasing pH, the phosphate groups were replaced by the deprotonated alcoholic [O] atoms of the sugar moiety. The solid complex proved to be tbp structure with bidentate phosphate coordination.

Melorheostosis of the hand with complicating bony spur formation and bursal inflammation: diagnosis and treatment

A 37-year old woman presented with intolerable pain associated with a slowly growing mass on the dorsum of the right hand. The radiographs were characteristic of melorheostosis involving the third and fourth metacarpals, with a cortical bony projection extending from the base of the third metacarpal eroding slightly into the fourth metacarpal, associated with bursal formation. Magnetic resonance imaging (MRI) demonstrated an inflamed bursal collection adjacent to the spur. This region corresponded to the patient's severe clinical, focal pain. To our knowledge, this is the first case report in which melorheostosis of the hand has been associated with bony spur formation and complicated by an inflamed bursa.

Role of tyrosine, DOPA and decarboxylase enzymes in the synthesis of monoamines in the brain of the locust

The metabolic transformation of tyrosine (TYR) by the decarboxylase and hydroxylase enzymes was investigated in the central nervous system of the locust, Locusta migratoria. It has been demonstrated that the key amino acids, 3,4-dihydroxyphenylalanine (DOPA), 5-hydroxytryptophan (5HTP) and tyrosine are decarboxylated in all part of central nervous system. DOPA and 5HTP decarboxylase activities show parallel changes in the different ganglia, but the rank order of the activity of TYR decarboxylase is different. Enzyme purification has revealed that the molecular weights of TYR decarboxylase and DOPA/5HTP decarboxylase are 370,000 and 112,000, respectively. The decarboxylation of DOPA by DOPA/5HTP decarboxylase is stimulated, whereas the decarboxylation of DOPA by TYR decarboxylase is inhibited in the presence of the cofactor pyridoxal-5'-phosphate. TYR hydroxylase could not be detected and 3H-TYR is found to be metabolised to tyramine (TA), but not to DOPA. The haemolymph contains a significant concentration of DOPA (120 pmol/100 microl haemolymph), and the ganglia incorporates DOPA from the haemolymph by a high affinity uptake process (K(M)=12 microM and V(max)=24 pmol per ganglion/10 min). Our results suggest that no tyrosine hydroxylase is present in the locust CNS and the DOPA uptake into the ganglia by a high affinity uptake process as well as the DOPA decarboxylase enzyme may be responsible for the regulation of the ganglionic dopamine (DA) level. Two types of decarboxylases exist, one of them decarboxylating DOPA and 5HTP (DOPA/5HTP decarboxylase), other decarboxylating TYR (TYR decarboxylase). The DOPA/5HTP decarboxylase enzyme present in the insect brain may correspond to the 5HTP/DOPA decarboxylase in vertebrate brain, whereas TYR decarboxylase is characteristic only for the insect brain.

Equilibrium and structural studies on metal complexes of carbohyrates and their derivatives

A summary is presented of the studies of our group on metal complexes of carbohydrates (aldoses, ketoses, mono-, di- and polysaccharides) and their derivatives (aldonic, alduronic acids, polyalcohols, amino sugars, amino acid sugar adducts, AMP, ATP, etc.). The results are reported of equilibrium, electrochemical, solution and solid-state structural studies of complexes of transition metals [Cu(II), Fe(III), Ni(II), Zn(II), Co(II), Ag(I), Mn in different oxidation states and organotin(IV)]. The structural parameters (coordination number, bond distance, and Debye-Waller factor) obtained by extended X-ray absorption fine structure spectroscopic (EXAFS) spectroscopy are discussed in detail. The general rules concerning the formation and structure of such complexes are emphasized.

Mental health insurance claims among spouses of frequent business travellers

OBJECTIVES

Following up on two earlier publications showing increased psychological stress and psychosocial effects of travel on the business travellers this study investigated the health of spouses of business travellers.

METHODS

Medical claims of spouses of Washington DC World Bank staff participating in the medical insurance programme in 1997-8 were reviewed. Only the first of each diagnosis with the ninth revision of the international classification of diseases (ICD-9) recorded for each person was included in this analysis. The claims were grouped into 28 diagnostic categories and subcategories.

RESULTS

There were almost twice as many women as men among the 4630 identified spouses. Overall, male and female spouses of travellers filed claims for medical treatment at about a 16% higher rate than spouses of non-travellers. As hypothesised, a higher rate for psychological treatment was found in the spouses of international business travellers compared with non-travellers (men standardised rate ratios (RR)=1.55; women RR=1.37). For stress related psychological disorders the rates tripled for both female and male spouses of frequent travellers (>or= four missions/year) compared with those of non-travelling employees. An increased rate of claims among spouses of travellers versus non-travellers was also found for treatment for certain other diagnostic groups. Of these, diseases of the skin (men RR=2.93; women RR=1.41) and intestinal diseases (men RR=1.31; women RR=1.47) may have some association with the spouses' travel, whereas others, such as malignant neoplasms (men RR=1.97; women RR=0.79) are less likely to have such a relation.

CONCLUSION

The previously identified pattern of increased psychological disorders among business travellers is mirrored among their spouses. This finding underscores the permeable boundary between family relations and working life which earlier studies suggested, and it emphasises the need for concern within institutions and strategies for prevention.

Avoidance of vascular compression in decompressive surgery for brain edema caused by trauma and tumor ablation

BACKGROUND

In case of severe brain swelling especially caused by trauma or other operative manipulation (tumor ablation), decompressive craniectomy with durotomy has not resulted in significant chances of recovery. Decompressive craniectomy has been defined only as an option within guidelines.

METHOD

A new operative technique was developed to improve the efficacy of decompressive surgery. With an increase in intracranial pressure (ICP) threatening with brainstem herniation, wide bilateral craniectomy was carried out, followed by dura opening and subsequent formation of a vascular tunnel in a simple way--using hemostatic sponge cushions--around the main cortical veins at the entering points of the herniated area. The maintenance of vessel patency prevents the herniated brain segment from venous congestion, i.e., from further swelling and necrosis.

RESULTS

Twenty operations with traumatic brain edema were performed using this vascular tunnel method. All patients were exposed to surgery in the state of coma. One operation was performed after tumor removal. The results were promising in comparison with the well-known surgical or conservative treatment.

DISCUSSION

Applying very strict selection criteria (Glasgow coma scale < 6, signs of severe edema on CT, or intracranial pressure permanently > or = 30 mmHg) in this small series of patients with severe brain injury, good results were achieved using the new operative technique. In case of postoperative edema after tumor ablation, it also showed promising results.