Highly efficient infrared optical nonlinearity of a wide-bandgap chalcogenide Li(2)CdGeS(4).

A quaternary chalcogenide Li(2)CdGeS(4) is an excellent candidate for a nonlinear optical (NLO) material exhibiting wide transparency spanning from its fundamental band edge (3.15 eV) to the terahertz regime (23.5 µm). Strong optical nonlinearity of Li(2)CdGeS(4) has been investigated over a wide spectral range (λ=1.064-3.3 µm) based on second- and third-harmonic generation. The compound has a high damage threshold at λ=1.064 µm because of saturable three-photon absorption, and is phase-matchable for λ>1.5 µm with χ(2) ≃50 pm/V. It also exhibits strong third-order nonlinearity of χ(3) ≃10(5) pm(2)/V(2). Li(2)CdGeS(4) is promising for high-power NLO applications in the broad infrared spectrum.

Dissecting the regions of virion-associated Kaposi's sarcoma-associated herpesvirus complement control protein required for complement regulation and cell binding.

Complement, which bridges innate and adaptive immune responses as well as humoral and cell-mediated immunity, is antiviral. Kaposi's sarcoma-associated herpesvirus (KSHV) encodes a lytic cycle protein called KSHV complement control protein (KCP) that inhibits activation of the complement cascade. It does so by regulating C3 convertases, accelerating their decay, and acting as a cofactor for factor I degradation of C4b and C3b, two components of the C3 and C5 convertases. These complement regulatory activities require the short consensus repeat (SCR) motifs, of which KCP has four (SCRs 1 to 4). We found that in addition to KCP being expressed on the surfaces of experimentally infected endothelial cells, it is associated with the envelope of purified KSHV virions, potentially protecting them from complement-mediated immunity. Furthermore, recombinant KCP binds heparin, an analogue of the known KSHV cell attachment receptor heparan sulfate, facilitating infection. Treating virus with an anti-KCP monoclonal antibody (MAb), BSF8, inhibited KSHV infection of cells by 35%. Epitope mapping of MAb BSF8 revealed that it binds within SCR domains 1 and 2, also the region of the protein involved in heparin binding. This MAb strongly inhibited classical C3 convertase decay acceleration by KCP and cofactor activity for C4b cleavage but not C3b cleavage. Our data suggest similar topological requirements for cell binding by KSHV, heparin binding, and regulation of C4b-containing C3 convertases but not for factor I-mediated cleavage of C3b. Importantly, they suggest KCP confers at least two functions on the virion: cell binding with concomitant infection and immune evasion.

LiEuPSe4 and KEuPSe4: novel selenophosphates with the tetrahedral [PSe4]3- building block.

LiEuPSe4, the first quaternary lithium-containing selenophosphate, was synthesized as red polyhedra by reacting Eu with a molten mixture of Li2Se/P2Se5/Se at 750 degrees C. Similarly, the reaction of Eu with a molten mixture of K2Se/P2Se5/Se at 495 degrees C produced red polyhedral crystals of KEuPSe4. Both compounds are unstable in moist air. In addition, both compounds were plagued with crystal twinning. Acceptable crystal structure refinements could only be obtained by identifying the type of twinning and taking it into account in the final refinement. LiEuPSe4 crystallizes in the noncentrosymmetric space group Ama2 (no. 40) with a = 10.5592 (9) A, b = 10.415 (1) A, c = 6.4924(7) A, and Z = 4. The structure is three-dimensional and composed of EuSe8 distorted square antiprisms and PSe4 tetrahedral building blocks that create tunnels, running down the a axis, in which the Li ions reside. The Li ions are in a highly distorted tetrahedral coordination. KEuPSe4 crystallizes in the space group P2(1)/m (no. 11) with a = 6.8469(6) A, b = 6.9521(6) A, c = 9.0436(8) A, beta = 107.677(2) degrees, and Z = 2. The structure has two-dimensional character with layers composed of EuSe6 trigonal prisms and PSe4 tetrahedral units. Between the [EuPSe4]nn- layers the K ions reside in a bicapped trigonal prism of Se atoms. The structure of the [EuPSe4]nn- framework is similar to that found in CsPbPSe4. Both compounds are semiconductors with band gaps of 2.00 and 1.88 eV, respectively. Differential thermal analysis and infrared spectroscopic characterization are also reported.

Economic evaluation of the use of nadroparin calcium in the prophylaxis of deep vein thrombosis and pulmonary embolism in surgical patients in Italy.

The objective of this study was to compare the costs, from the perspective of the payer, of using nadroparin calcium, a low-molecular-weight heparin, instead of unfractionated heparin in the prophylaxis of venous thromboembolism in patients undergoing orthopaedic surgery or major general surgery in Italy. The methods used were based on a published meta-analysis and a survey of clinical practice. We constructed a model of the prophylaxis and management of venous thromboembolism in Italy. Resource use associated with individual events was estimated on the basis of the clinical survey. Unit costs, not available from published sources, were taken from charges made by hospitals and from direct observation. A sensitivity analysis was conducted to examine whether the results were robust to changes in key variables. In the base case, compared with unfractionated heparin, prophylaxis with nadroparin calcium reduced the expected costs of managing thromboembolism by 267,226 Italian lire (L, 1994 values; $US1 = L1600 approx.) per patient undergoing orthopaedic surgery, and by L45,588 per patient undergoing major general surgery. Therefore, switching from unfractionated heparin to nadroparin calcium in these patients offers the possibility of significant cost savings to the Italian healthcare system.

Economic evaluation of the use of nadroparin in the treatment of deep-vein thrombosis in Switzerland.

OBJECTIVE: To compare the cost implications, from the payer's perspective, of the use of nadroparin instead of unfractionated heparin in the initial treatment of deep-vein thrombosis. DESIGN: Cost-minimization study. SETTING: Switzerland. MATERIAL: Survey of clinical practice in six Swiss hospitals used to model three treatment regimens. MAIN OUTCOME MEASURES: Cost of treatment ($ US) per patient. RESULTS: Treatment with nadroparin instead of unfractionated heparin would reduce costs by $153 per patient. Treatment with nadroparin instead of subcutaneous unfractionated heparin would reduce costs by $109 per patient. CONCLUSIONS: The cost of initial treatment of deep-vein thrombosis is considerably lower with nadroparin than with either of the alternative regimens. Nadroparin reduces costs through greater ease of administration and by reducing the amount of laboratory monitoring. Treatment with nadroparin might also allow patients to be discharged from the hospital more quickly than is possible with intravenous infusion of unfractionated heparin.

Role of fibronectin in the organisation of the cytoskeleton during the spreading of rat mammary epithelial cells.

The correlation between the extracellular deposition of fibronectin and the development of the actin-containing cytoskeleton was studied during the attachment and spreading of the rat mammary epithelial cell line Rama 25. During the initial phase of cell spreading, actin is localised in peripheral microfilament bundles. As cell spreading increases, the peripheral ring is displaced towards the perinuclear region. Fibronectin, deposited beneath the basal surface, co-localises with the actin-containing peripheral ring. The peripheral ring subsequently disappears and is replaced by a system of radial microfilaments that extend from the perinuclear region to the cell periphery. At this stage, there is no correlation between the distribution of fibronectin and actin. As cells form colonies, radial microfilament bundles are replaced by peripheral microfilament bundles which do not co-localise with fibronectin. Cells at the edges of colonies extend lamellae that contain microfilament stress fibres. In these structures there is co-localisation of actin, fibronectin and the a5 beta 1-integrin fibronectin receptor.

Diagnosis and management of parkinsonism in the elderly.

Of 123 patients with parkinsonism attending a department of medicine for the elderly who were assessed, 73% were thought to have idiopathic Parkinson's disease, and 91% of these cases and 52% of the remaining cases had a history of rest tremor; 34% of all cases were demented. The prevalence of dementia did not correlate with the duration of disease. Demented patients with presumed idiopathic Parkinson's disease were not distinguishable from non-demented by duration of disease, presence of a history of rest tremor or use of L-dopa. Eighty-eight per cent of non-demented patients but only 44% of demented patients were thought to have responded to L-dopa. Lower doses of L-dopa were used than are conventional with younger patients.