Mass density images from the diffraction enhanced imaging technique

Conventional x-ray radiography measures the projected x-ray attenuation of an object. It requires attenuation differences to obtain contrast of embedded features. In general, the best absorption contrast is obtained at x-ray energies where the absorption is high, meaning a high absorbed dose. Diffraction-enhanced imaging (DEI) derives contrast from absorption, refraction, and extinction. The refraction angle image of DEI visualizes the spatial gradient of the projected electron density of the object. The projected electron density often correlates well with the projected mass density and projected absorption in soft-tissue imaging, yet the mass density is not an "energy"-dependent property of the object, as is the case of absorption. This simple difference can lead to imaging with less x-ray exposure or dose. In addition, the mass density image can be directly compared (i.e., a signal-to-noise comparison) with conventional radiography. We present the method of obtaining the mass density image, the results of experiments in which comparisons are made with radiography, and an application of the method to breast cancer imaging.

C-peptide stimulates ERK1/2 and JNK MAP kinases via activation of protein kinase C in human renal tubular cells

AIMS/HYPOTHESIS

Accumulating evidence indicates that replacement of C-peptide in type 1 diabetes ameliorates nerve and kidney dysfunction, but the molecular mechanisms involved are incompletely understood. C-peptide shows specific binding to a G-protein-coupled membrane binding site, resulting in Ca(2+) influx, activation of mitogen-activated protein kinase signalling pathways, and stimulation of Na(+), K(+)-ATPase and endothelial nitric oxide synthase. This study examines the intracellular signalling pathways activated by C-peptide in human renal tubular cells.

METHODS

Human renal tubular cells were cultured from the outer cortex of renal tissue obtained from patients undergoing elective nephrectomy. Extracellular-signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK) and Akt/protein kinase B (PKB) activation was determined using phospho-specific antibodies. Protein kinase C (PKC) and RhoA activation was determined by measuring their translocation to the cell membrane fraction using isoform-specific antibodies.

RESULTS

Human C-peptide increases phosphorylation of ERK1/2 and Akt/PKB in a concentration- and time-dependent manner in renal tubular cells. The C-terminal pentapeptide of C-peptide is equipotent with the full-length C-peptide, whereas scrambled C-peptide has no effect. C-peptide stimulation also results in phosphorylation of JNK, but not of p38 mitogen-activated protein kinase. MEK1/2 inhibitor PD98059 blocks the C-peptide effect on ERK1/2 phosphorylation. C-peptide causes specific translocation of PKC isoforms delta and epsilon to the membrane fraction in tubular cells. All stimulatory effects of C-peptide were abolished by pertussis toxin. The isoform-specific PKC-delta inhibitor rottlerin and the broad-spectrum PKC inhibitor GF109203X both abolish the C-peptide effect on ERK1/2 phosphorylation. C-peptide stimulation also causes translocation of the small GTPase RhoA from the cytosol to the cell membrane. Inhibition of phospholipase C abolished the stimulatory effect of C-peptide on phosphorylation of ERK1/2, JNK and PKC-delta.

CONCLUSIONS/INTERPRETATION

C-peptide signal transduction in human renal tubular cells involves the activation of phospholipase C and PKC-delta and PKC-epsilon, as well as RhoA, followed by phosphorylation of ERK1/2 and JNK, and a parallel activation of Akt.

C-peptide stimulates Na+, K+-ATPase via activation of ERK1/2 MAP kinases in human renal tubular cells

Proinsulin-connecting peptide (C-peptide) exerts physiological effects partially via stimulation of Na(+), K(+)-ATPase. We determined the molecular mechanism by which C-peptide stimulates Na(+), K(+)-ATPase in primary human renal tubular cells (HRTCs). Incubation of the cells with 5 nM human C-peptide at 37 degrees C for 10 min stimulated (86)Rb(+) uptake by 40% (p<0.01). The carboxy-terminal pentapeptide was found to elicit 57% of the activity of the intact molecule. In parallel with ouabain-sensitive (86)Rb(+) uptake, C-peptide increased alpha subunit phosphorylation and basolateral membrane (BLM) abundance of the Na(+), K(+)-ATPase alpha(1) and beta(1) subunits. The increase in BLM abundance of the Na(+), K(+)-ATPase alpha(1) and beta(1) subunits was accompanied by depletion of alpha(1) and beta(1) subunits from the endosomal compartments. C-peptide action on Na(+), K(+)-ATPase was ERK1/2-dependent in HRTCs. C-peptide-stimulated Na(+), K(+)-ATPase activation, phosphorylation of alpha(1)-subunit and translocation of alpha(1) and beta(1) subunits to the BLM were abolished by a MEK1/2 inhibitor (20 muM PD98059). C-peptide stimulation of (86)Rb(+) uptake was also abolished by preincubation of HRTCs with an inhibitor of PKC (1 muM GF109203X). C-peptide stimulated phosphorylation of human Na(+), K(+)-ATPase alpha subunit on Thr-Pro amino acid motifs, which form specific ERK substrates. In conclusion, C-peptide stimulates sodium pump activity via ERK1/2-induced phosphorylation of Thr residues on the alpha subunit of Na(+), K(+)-ATPase.

Direct determination of strain and composition profiles in SiGe islands by anomalous x-Ray diffraction at high momentum transfer

Anomalous x-ray scattering is employed for quantitative measurements of the Ge composition profile in islands on Si(001). The anomalous effect in SiGe is enhanced exploiting the dependence of the complex atomic form factors on the momentum transfer. Comparing the intensity ratios for x-ray energies below and close to the K edge of Ge at various Bragg reflections in the grazing incidence diffraction setup, the sensitivity for the Ge profile is considerably enhanced. The method is demonstrated for SiGe dome-shaped islands grown on Si(001). It is found that the composition inside the island changes rather abruptly, whereas the lattice parameter relaxes continuously.

A lamellar model for the X-ray rocking curves of sagittally bent Laue crystals

The use of sagittally bent asymmetric Laue crystals in horizontally focusing monochromators for high-energy synchrotron X-rays necessitates simulation of the X-ray reflectivity by such crystals. Based on the theory of the lattice distortion in the diffraction plane of sagittally bent Laue crystals, a lamellar model was developed to predict their rocking curves. The model was experimentally verified by rocking-curve measurements from various reflections on silicon crystals of four representative orientations, sagittally bent to various radii, using X-rays of 67 keV energy.

An improved resazurin-based cytotoxicity assay for hepatic cells

A simple resazurin-based cytotoxicity assay is presented for screening of cytotoxicity in hepatocytes and liver cell lines. Human hepatoma (HepG2) cells in 96-well culture plates were exposed to known toxic (cisplatin, 5-fluorouracil, ethionine, flufenamic acid, and diflunisal) and control (transplatin, 5-chlorouracil, methionine, and acetylsalicylic acid) compounds for 1-3 days, and resazurin (5 micromol/L) was added. A conventional short-term (1 h) assay was first performed, where cytotoxicity is indicated by decreased reduction of resazurin to its fluorescent product resorufin. Our improved assay consists of additionally measuring fluorescence 2-4 days later, when cytotoxicity is indicated by a striking increase in the concentration of resorufin, resulting from two distinct processes. First, viable liver-derived cells slowly convert resorufin to nonfluorescent metabolites. Fluorescence of control cell wells decreased to background during a 2- to 4-day exposure to resazurin. This metabolism of resorufin was largely blocked by dicumarol and to lesser extents by disulfiram and SKF525a. Second, dead or dying cells slowly convert resazurin to resorufin but do not further metabolize resorufin; thus this fluorescent metabolite accumulates to high levels in wells with dead cells by 2 to 4 days. A similar increase in fluorescence associated with cytotoxicity was observed in primary cultures of rat hepatocytes using the long-term resazurin-based assay. In addition to an improved signal relative to the short-term assay, the inversion of the fluorescent signal from high = alive short-term to high = dead long-term allows determination of two independent cytotoxicity endpoints after addition of one innocuous vital dye.

Diffraction enhanced imaging contrast mechanisms in breast cancer specimens

We have investigated the contrast mechanisms of the refraction angle, and the apparent absorption images obtained from the diffraction enhanced imaging technique (DEI) and have correlated them with the absorption contrast of conventional radiography. The contrast of both the DEI refraction angle image and the radiograph have the same dependence on density differences of the tissues in the visualization of cancer; in radiography these differences directly relate to the contrast while in the DEI refraction angle image it is the density difference and thickness gradient that gives the refraction angle. We show that the density difference of fibrils in breast cancer as measured by absorption images correlate well with the density difference derived from refraction angle images of DEI. In addition we find that the DEI apparent absorption image and the image obtained with the DEI system at the top of the reflectivity curve have much greater contrast than that of the normal radiograph (x8 to 33-fold higher). This is due to the rejection of small angle scattering (extinction) from the fibrils enhancing the contrast.

Rocking-curve width of sagittally bent Laue crystals

The use of bent asymmetric Laue crystals to sagittally focus high-energy synchrotron X-rays calls for an understanding of the mechanisms affecting X-ray diffraction by such crystals. The rocking-curve width, a measurable quantity directly related to the distortion of the lattice planes, is the necessary first step towards such an understanding. A model is formulated for assessing the rocking-curve widths of sagittally bent Laue crystals, considering the elastic anisotropy. A method for depth-resolved measurement of the rocking curves was also developed to verify the model. The model successfully explains the wide range of rocking-curve widths of a large number of reflections from silicon crystals with two different orientations.

Structure-function relationships for human antibodies to pneumococcal capsular polysaccharide from transgenic mice with human immunoglobulin Loci

To investigate the influence of antibody structure and specificity on antibody efficacy against Streptococcus pneumoniae, human monospecific antibodies (MAbs) to serotype 3 pneumococcal capsular polysaccharide (PPS-3) were generated from transgenic mice reconstituted with human immunoglobulin loci (XenoMouse mice) vaccinated with a PPS-3-tetanus toxoid conjugate and their molecular genetic structures, epitope specificities, and protective efficacies in normal and complement-deficient mice were determined. Nucleic acid sequence analysis of three MAbs (A7, 1A2, and 7C5) revealed that they use two different V(H)3 genes (A7 and 1A2 both use V3-15) and three different V(kappa) gene segments. The MAbs were found to have similar affinities for PPS-3 but different epitope specificities and CDR3 regions. Both A7 and 7C5 had a lysine at the V(H)-D junction, whereas 1A2 had a threonine. Challenge experiments with serotype 3 S. pneumoniae in BALB/c mice revealed that both 10- and 1- micro g doses of A7 and 7C5 were protective, while only a 10- micro g dose of 1A2 was protective. Both A7 and 7C5 were also protective in mice lacking either an intact alternative (FB(-/-)) or classical (C4(-/-)) complement pathway, but 1A2 was not protective in either strain. Our data suggest that PPS-3 consists of epitopes that can elicit both highly protective and less protective antibodies and that the superior efficacies of certain antibodies may be a function of their structures and/or specificities. Further investigation of relationships between structure, specificity, and efficacy for defined MAbs to PPS may identify antibody features that might be useful surrogates for antibody (and vaccine) efficacy.

Proinsulin C-peptide and its analogues induce intracellular Ca2+ increases in human renal tubular cells

Based on the findings that proinsulin C-peptide binds specifically to cell membranes, we investigated the effects of C-peptide and related molecules on the intracellular Ca2+ concentration ([Ca2+]i) in human renal tubular cells using the indicator fura-2/AM. The results show that human C-peptide and its C-terminal pentapeptide (positions 27-31, EGSLQ), but not the des (27-31) C-peptide or randomly scrambled C-peptide, elicit a transient increase in [Ca2+]i. Rat C-peptide and rat C-terminal pentapeptide also induce a [Ca2+]i response in human tubular cells, while a human pentapeptide analogue with Ala at position 1 gives no [Ca2+]i response, and those with Ala at positions 2-5 induce responses with different amplitudes. These results define a species cross-reactivity for C-peptide and demonstrate the importance of Glu at position 1 of the pentapeptide. Preincubation of cells with pertussis toxin abolishes the effect on [Ca2+]i by both C-peptide and the pentapeptide. These results are compatible with previous data on C-peptide binding to cells and activation of Na-,K+ATPase. Combined, all data show that C-peptide is a bioactive peptide and suggest that it elicits changes in [Ca2+]i via G-protein-coupled pathways, giving downstream enzyme effects.

Nile Red binding to HepG2 cells: an improved assay for in vitro studies of hepatosteatosis

Nile Red is a fluorescent dye used extensively to study fat accumulation in many types of cells; unfortunately protocols that work well for most cells are not effective for studying drug-induced lipid accumulation in cultured liver cells and hepatocyte-derived cell lines. Using human hepatoma (HepG2) cells, we have developed a simple Nile Red binding assay as a screen for steatosis-inducing compounds. Increases in Nile Red binding in response to known hepatotoxic compounds were observed after incubating treated cells with 1 microM Nile Red for several hours, washing away free Nile Red, and then allowing redistribution, and/or clearance of the lipid-indicator dye. Several compounds known to cause hepatic fat accumulation in vivo were examined and most robustly increased Nile Red binding in HepG2 cells. These include estrogen and other steroids, ethionine, cyclosporin A, and valproic acid. Required concentrations for increased Nile Red binding were generally three-fold or more lower than the cytotoxic concentration determined by a resazurin reduction assay in the same cells. Qualitatively similar Nile Red binding results were obtained when primary canine or rat hepatocytes were used. Morphological differences in Nile Red staining were observed by confocal fluorescence microscopy in HepG2 cells after treatment with different compounds and likely reflect distinct toxicological mechanisms.

Diffraction-enhanced X-ray imaging of articular cartilage

OBJECTIVE

To introduce a novel X-ray technology, diffraction-enhanced X-ray imaging (DEI), in its early stages of development, for the imaging of articular cartilage.

DESIGN

Disarticulated and/or intact human knee and talocrural joints displaying both undegenerated and degenerated articular cartilage were imaged with DEI. A series of three silicon crystals were used to produce a highly collimated monochromatic X-ray beam to achieve scatter-rejection at the microradian level. The third crystal (analyser) was set at different angles resulting in images displaying different characteristics. Once the diffraction enhanced (DE) images were obtained, they were compared to gross and histological examination.

RESULTS

Articular cartilage in both disarticulated and intact joints could be visualized through DEI. For each specimen, DE images were reflective of their gross and histological appearance. For each different angle of the analyser crystal, there was a slight difference in appearance in the specimen image, with certain characteristics changing in their contrast intensity as the analyser angle changed.

CONCLUSIONS

DEI is capable of imaging articular cartilage in disarticulated, as well as in intact joints. Gross cartilage defects, even at early stages of development, can be visualized due to a combination of high spatial resolution and detection of X-ray refraction, extinction and absorption patterns. Furthermore, DE images displaying contrast heterogeneities indicative of cartilage degeneration correspond to the degeneration detected by gross and histological examination.

Viral gene delivery of superoxide dismutase attenuates experimental cholestasis-induced liver fibrosis in the rat

Hydrophobic bile acids lead to generation of oxygen free radicals in mitochondria. Accordingly, this study investigated if gene delivery of superoxide dismutase (SOD) would reduce hepatic injury caused by experimental cholestasis. Rats were given adenovirus (Ad; 3 x 10(9) p.f.u., i.v.) carrying the bacterial control gene lacZ, mitochondrial Mn-SOD or cytosolic Cu/Zn-SOD genes 3 days before bile duct ligation. Both Mn- and Cu/Zn-SOD activity was increased in the liver about four-fold 3 days after viral infection. Serum alanine transaminase increased to about 710 U/l after bile duct ligation, which was blunted by about 70% in rats receiving Ad-Mn-SOD, but by only 30% in rats receiving Ad-Cu/Zn-SOD. Bile duct ligation caused focal necrosis, apoptosis and fibrosis in the liver and increased collagen alpha1 mRNA about 20-fold. These effects were reduced significantly by Ad-Mn-SOD, but not by Ad-Cu/Zn-SOD. In addition, bile duct ligation increased 4-hydroxynonenal, a product of lipid peroxidation, activated NF-kappaB and increased synthesis of TNF(alpha) and TGF-beta. These effects were also blunted significantly by Ad-Mn-SOD, but not by Ad-Cu/Zn-SOD. Taken together, it is concluded that cholestasis causes liver injury by mechanisms involving mitochondrial oxidative stress. Gene delivery of mitochondrial Mn-SOD blocks formation of oxygen radicals and production of toxic cytokines thereby minimizing liver injury caused by cholestasis.

Sequence analysis of a 101-kilobase plasmid required for agar degradation by a Microscilla isolate

An agar-degrading marine bacterium identified as a Microscilla species was isolated from coastal California marine sediment. This organism harbored a single 101-kb circular DNA plasmid designated pSD15. The complete nucleotide sequence of pSD15 was obtained, and sequence analysis indicated a number of genes putatively encoding a variety of enzymes involved in polysaccharide utilization. The most striking feature was the occurrence of five putative agarase genes. Loss of the plasmid, which occurred at a surprisingly high frequency, was associated with loss of agarase activity, supporting the sequence analysis results.

Cyclosporin A causes a hypermetabolic state and hypoxia in the liver: prevention by dietary glycine

Acute cyclosporin A (CsA) treatment inhibits mitochondrial respiration, yet effects of chronic treatment remain unclear. Accordingly, the effects of chronic CsA on oxygen metabolism in perfused rat liver and isolated mitochondria were investigated. Basal rates of oxygen uptake of around 120 micromol/g/h in isolated perfused livers from vehicle-treated controls were elevated about 1.6-fold by chronic CsA treatment. In the presence of ammonium chloride, a substrate for urea synthesis, oxygen uptake was about 150 micromol/g/h and was increased about 1.7-fold by CsA, indicating that chronic CsA treatment causes a robust hypermetabolic state in the liver. In isolated mitochondria, state 3 rates of oxygen uptake were increased about 1.6-fold by chronic CsA treatment. Since significant increases in oxygen consumption could cause hypoxia, the hypoxia marker pimonidazole was given. Pimonidazole binding in the liver was increased about 3-fold by chronic CsA. Moreover, intracellular calcium in Kupffer cells isolated from vehicle-treated rats was not altered by CsA addition; however, in cells isolated from chronic CsA-treated rats, CsA increased intracellular calcium about 15-fold and prostaglandin E(2) (PGE(2)) production 3.5-fold. Importantly, dietary glycine (5%) largely blocked chronic CsA-induced activation of Kupffer cells, blunted production of PGE(2), prevented the hypermetabolic state, and minimized tissue hypoxia. Taken together, it is concluded that chronic CsA treatment causes a hypermetabolic state leading to hypoxia and injury to the liver. It is hypothesized that CsA activates Kupffer cells and increases production of PGE(2), which alters mitochondria leading to a hypermetabolic state. Glycine inhibits activation of Kupffer cells thus preventing liver injury.

[Pharmacological study on the extracts from Typhonium flagelliforme Blume]

OBJECTIVE

To study the pharmacological action of Typhonium flagelliforme Blune(TFB).

METHODS

Relieving a cough and eliminating expectoration were observed by strong aqua spray and pheol red determining methods. The antiasthmatic action was observed by whole spraying method. The analgesia and anti-inflammation were studied by the twisting test induced by acetic acid and ear swelling induced by xylene. The sedation was determined by autonomic action test. The toxicity of TFB was studied through the acute toxicity test in mice.

RESULTS

All the water, alcohol and ester extracts of TFB could significantly decrease cough times, increase phenol red outage in trachea, prolong asthma incubation period, decrease twisting times, inhibit ear swelling and decrease autonomic action times.

CONCLUSION

All water, alcohol and ester extracts of TFB have effects of relieving a cough, eliminating expectoration, antiasthmatic, analgesia, anti-inflammation and sedation. The maximum tolerances of TFB for acute toxicity were 720 g/kg(water extract), 900 g/kg (alcohol extract) 3240 g/kg(ester extract) respectively.

Sagittal focusing of high-energy synchrotron X-rays with asymmetric Laue crystals. II. Experimental studies

The use of bent asymmetric Laue crystals to focus synchrotron X-rays sagittally from 15 to 50 keV is described. A four-bar bender, bending a rectangular planar crystal, produced the necessary sagittal and meridional bending for this unique application. Adjustments of the tilt angle and height of the bent crystal resulted in first- and second-order corrections, respectively, to the dependence of the angle of diffraction on the horizontal position on the crystal. After these corrections, the remaining variation of the diffraction angle was of the order of 10 µrad. The theoretical sagittal focal length was verified. A prototype of a double-crystal sagittally focusing monochromator was constructed and tested, using two identical Laue crystals. A horizontal divergence of 3 mrad was focused to a horizontal dimension of about 0.4 mm. The X-ray flux density at the focus was a few hundred times larger than that of unfocused X-rays.

Producing parallel x rays with a bent-crystal monochromator and an x-ray tube

A bent Laue monochromator and a conventional x-ray tube were used to produce a fan beam that was parallel in the plane perpendicular to the plane of the fan. The x-ray fan beam was tunable in energy and had about 12% energy bandwidth at a slice height of 5 mm when tuned to 50 keV. The beam's energy was slightly coupled to the vertical position on the beam's height. The slice height could be varied from 1 to 10 mm. The flux at 50 keV was approximately 2x10(6) photons/mm2/s with a rotating anode tungsten x-ray tube operating at 120 kVp and 100 mA. The narrow energy bandwidth of the beam produced is advantageous over a conventional divergent polychromatic beam for all radiography applications, while the parallelism of the beam enhances its intensity by about threefold and offers some advantages for computed tomography.

Cytochrome P450 induction in rat hepatocytes assessed by quantitative real-time reverse-transcription polymerase chain reaction and the RNA invasive cleavage assay

The acceleration of drug discovery due to combinatorial chemistry and high-throughput screening methods has increased the numbers of candidate pharmaceuticals entering the drug development phase, and the capability to accurately predict whether drug candidates will induce various members of the drug-metabolizing cytochrome P450 (CYP) enzyme superfamily is currently of great interest to the pharmaceutical industry. In the present study, we describe the rapid and reliable analysis of CYP induction in a readily obtained model system (cultured rat hepatocytes) using both real-time quantitative reverse transcription-polymerase chain reaction (real-time RT-PCR) and the RNA invasive cleavage assay. The levels of members in the three primary inducible rat CYP subfamilies (CYP1A1, CYP2B1/2, and CYP3A1) were analyzed in untreated and induced (beta-naphthoflavone, phenobarbital, and hydrocortisone) hepatocyte cultures under various media conditions to screen for optimal CYP induction profiles. The fold inductions measured by real-time RT-PCR and the RNA invasive cleavage assay were also compared with enzyme activity measurements in parallel cultures using liquid chromatography/double mass spectrometry-based assays, and the sensitivity and the specificity of the two RNA analysis methods were compared. Using these techniques, various culture conditions were examined for optimizing induction of the three CYP subfamily members. Both real-time RT-PCR and the RNA invasive cleavage assay prove to be effective methods for determining the effects of drugs on specific CYPs in primary rat hepatocytes.

Protection against glutamate toxicity through inhibition of the p44/42 mitogen-activated protein kinase pathway in neuronally differentiated P19 cells

Excessive levels of the neurotransmitter glutamate trigger excitotoxic processes in neurons that lead to cell death. N-Methyl-D-aspartate (NMDA) receptor over-activation is a key excitotoxic stimulus that leads to increases in intracellular calcium and activation of downstream signaling pathways, including the p44/42 mitogen-activated protein (MAP) kinase pathway. In the present study, we have demonstrated that 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio]butadiene (U0126), a potent and selective inhibitor of the p44/42 MAP kinase signaling pathway, prevents glutamate-induced death in neuronally differentiated P19 cells. In addition, we show that differentiated, but not undifferentiated, P19 cells expressed zeta1, epsilon1, and epsilon2 subunits of the NMDA receptor. Differentiated P19 cells exhibited specific NMDA receptor binding and intracellular calcium responses to glutamate that were blocked by the selective NMDA receptor antagonist [5R,10S]-[+]-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine (MK-801), but not U0126. Glutamate treatment of differentiated P19 cells triggered a rapid and sustained induction in p42 MAP kinase phosphorylation that was blocked by U0126. Pretreatment of differentiated P19 cells with U0126, but not other classes of protein kinase inhibitors, protected against glutamate-induced cell death. Post-treatment with U0126, even as late as 6 hr after glutamate application, also protected against glutamate toxicity. These results suggest that the p44/42 MAP kinase pathway may be a critical downstream signaling pathway in glutamate receptor-activated toxicity.

Sagittal focusing of high-energy synchrotron X-rays with asymmetric Laue crystals. I. Theoretical considerations

The ability of asymmetric Laue crystals to focus X-rays sagittally is demonstrated. The extent of such focusing is similar to that of sagittal focusing by a Bragg crystal, except for a factor related to the asymmetry angle. The anticlastic bending facilitates the use of inverse-Cauchois geometry in the meridional plane to provide better energy resolution and to increase the photon flux by an order of magnitude compared with traditional sagittal focusing with Bragg crystals. Furthermore, for sagittal focusing at X-ray energies above 30 keV, a Laue crystal is preferred to a Bragg crystal because the length of the beam's footprint on a Laue crystal, unlike on a Bragg crystal, is small and insensitive to energy. The conditions imposed on the asymmetry angle of the Laue crystal to achieve simultaneous sagittal focusing and inverse-Cauchois geometry in the meridional plane are derived for both single-crystal and double-crystal fixed-exit sagittally focusing monochromators.

C-Peptide Binding to Human Cell Membranes: Importance of Glu27

In addition to its established role in proinsulin folding, C-peptide has a function in regulation of cellular activity. The 31-residue peptide influences renal, vascular, and metabolic functions in patients with insulin-dependent diabetes mellitus. Binding to cells has been demonstrated for C-peptide, which can be displaced by its C-terminal pentapeptide. We have now used fluorescence correlation spectroscopy to investigate structural requirements on the pentapeptide part for C-peptide binding. All pentapeptide residues, E(27)GSLQ(31), were individually replaced with Ala and the capacity of the resulting peptides to displace rhodamine-labelled full-length human C-peptide from human renal tubular cell membranes was determined. This showed that Glu27 is essential for displacement, while replacement of Gly28 with Ala has little effect, and replacement of any of the three most C-terminal residues had intermediate effects. Morevover, free Glu displaces full-length C-peptide to about 50%, while free Ala, C-peptide(1-26), and the truncated pentapeptide, corresponding to the tetrapeptide G(28)SLG(31), have no displacing capacity. The peptides EVARQ (corresponding to the rat C-terminal pentapeptide) and ELGGGPGAG (corresponding to positions 11-19 of human C-peptide) do not displace human C-peptide. These results indicate that Glu27 of C-peptide is critically involved in binding to cellular targets.

A self-assembled homooxacalix[3]arene-based dimeric capsule constructed by a Pd(II)-pyridine interaction which shows a novel chiral twisting motion in response to guest inclusion

A capsule-like molecule was constructed by dimerization of pyridine-containing homooxacalix[3]aryl esters utilizing a Pd(II)-pyridine interaction when Li(+) ions were bound to the ionophoric lower rims. (1)H NMR spectral studies showed that the self-assembled molecular capsule 3b.(Li(+))(2) has a highly symmetrical D(3)(h)-structure. It was also found that this self-assembled molecular system can form capsular structures in the presence of Na(+) or ammonium (RNH(3)(+)) ions. Very interestingly, these molecular capsules are twisted into triply bridged helical structures, and chiral RNH(3)(+) guests included in the cavity induce a change in the (P) versus (M) ratio, resulting in high chiral induction ( approximately 70%). These results indicate that the self-assembled molecular capsule 3b has a novel chiral factor in which the (P) versus (M) equilibrium is readily controllable by the inclusion of chiral guest molecules.

Response of avian embryonic brain to spatially segmented x-ray microbeams

Duck embryo was studied as a model for assessing the effects of microbeam radiation therapy (MRT) on the human infant brain. Because of the high risk of radiation-induced disruption of the developmental process in the immature brain, conventional wide-beam radiotherapy of brain tumors is seldom carried out in infants under the age of three. Other types of treatment for pediatric brain tumors are frequently ineffective. Recent findings from studies in Grenoble on the brain of suckling rats indicate that MRT could be of benefit for the treatment of early childhood tumors. In our studies, duck embryos were irradiated at 3-4 days prior to hatching. Irradiation was carried out using a single exposure of synchrotron-generated X-rays, either in the form of parallel microplanar beams (microbeams), or as non-segmented broad beam. The individual microplanar beams had a width of 27 microm and height of 11 mm, and a center-to-center spacing of 100 microm. Doses to the exposed areas of embryo brain were 40, 80, 160 and 450 Gy (in-slice dose) for the microbeam, and 6, 12 and 18 Gy for the broad beam. The biological end point employed in the study was ataxia. This neurological symptom of radiation damage to the brain developed within 75 days of hatching. Histopathological analysis of brain tissue did not reveal any radiation induced lesions for microbeam doses of 40-160 Gy (in-slice), although some incidences of ataxia were observed in that dose group. However, severe brain lesions did occur in animals in the 450 Gy microbeam dose groups, and mild lesions in the 18 Gy broad beam dose group. These results indicate that embryonic duck brain has an appreciably higher tolerance to the microbeam modality, as compared to the broad beam modality. When the microbeam dose was normalized to the full volume of the irradiated tissue. i.e., the dose averaged over microbeams and the space between the microbeams, brain tolerance was estimated to be about three times higher to microbeam irradiation as compared with broad beam irradiation.

Polarization rotation via a monoclinic phase in the piezoelectric 92% PbZn(1/3)Nb(2/3)O3-8% PbTiO3

The origin of ultrahigh piezoelectricity in the relaxor ferroelectric PbZn(1/3)Nb(2/3)O3-PbTiO3 was studied with an electric field applied along the [001] direction. The zero-field rhombohedral R phase starts to follow the direct polarization path to tetragonal symmetry via an intermediate monoclinic M phase, but then jumps irreversibly to an alternate path involving a different type of monoclinic distortion. Details of the structure and domain configuration of this novel phase are described. This result suggests that there is a nearby R-M phase boundary as found in the Pb(Ti,Zr)O3 system.

Multicopy plasmids are clustered and localized in Escherichia coli

We localized the multicopy plasmid RK2 in Escherichia coli and found that the number of fluorescent foci observed in each cell was substantially less than the copy number of the plasmid, suggesting that many copies of RK2 are grouped into a few multiplasmid clusters. In minimal glucose media, the majority of cells had one or two foci, with a single focus localized near midcell, and two foci near the 1/4 and 3/4 cell positions. The number of foci per cell increased with cell length and with growth rate, and decreased upon entering stationary phase, suggesting a coordination of RK2 replication or segregation with the bacterial cell cycle. Time-lapse microscopy demonstrated that partitioning of RK2 foci is achieved by the splitting of a single focus into two or three smaller foci, which are capable of separating with rapid kinetics. A derivative of the high-copy-number plasmid pUC19 containing the lacO array was also localized by tagging with GFP-LacI. Whereas many of the cells contained numerous, randomly diffusing foci, most cells exhibited one or two plasmid clusters located at midcell or the cell quarter positions. Our results suggest a model in which multicopy plasmids are not always randomly diffusing throughout the cell as previously thought, but can be replicated and partitioned in clusters targeted to specific locations.

Creation of novel chiral cryptophanes by a self-assembling method utilizing a pyridyl-Pd(II) interaction

[structure: see text]. This Letter demonstrates the molecular design of novel self-assembled chiral cryptophanes. Mediated by square-planar Pd(II) complexes, racemic pyridyl cyclotriveratrylene derivative rac-2 self-assembles into mixtures of racemic chiral cryptophanes and meso cryptophanes (1), which interconvert with each other, and the rates are remarkably enhanced by the addition of a slight excess of rac-2. On the other hand, optically resolved P-2 or M-2 self-assembles into the chiral cryptophane as the only product.

Viral delivery of superoxide dismutase gene reduces cyclosporine A-induced nephrotoxicity

BACKGROUND

Cyclosporine A (CsA) increases free radical formation in the kidney. Accordingly, this study investigated whether gene delivery of superoxide dismutase (SOD) reduced radical production and nephrotoxicity caused by CsA.

METHODS

Rats were given adenovirus (Ad) carrying lacZ or Cu/Zn-SOD genes three days prior to CsA treatment. Histology, glomerular filtration rates (GFRs) and free radical adducts in urine were assessed.

RESULTS

SOD activity was increased 2.5-fold three days after viral infection and remained at 2- and 1.6-fold higher 10 and 17 days later. Treatment with CsA for seven days decreased GFR by 70% in rats infected with Ad-lacZ as expected; however, the decrease was diminished significantly in rats receiving Ad-SOD. CsA treatment for two weeks caused a loss of brush border and dilation of proximal tubules, necrosis, and increased leukocyte infiltration into the kidney; these effects were minimized by SOD. Dimethyl sulfoxide (DMSO) was attacked by the hydroxyl radical to produce a methyl radical. Indeed, administration of CsA with 12C-DMSO in rats infected with Ad-lacZ produced a radical adduct with hyperfine coupling constants similar to 4-POBN/methyl radical adduct and another unknown radical adduct. CsA given with 13C-DMSO produced a 12-line spectrum, confirming the involvement of hydroxyl radicals. Free radical adducts detected in urine were increased approximately fivefold by CsA, an effect blocked completely by SOD.

CONCLUSIONS

CsA increases free radical formation. Gene delivery of SOD blocks formation of free radicals, thereby minimizing nephrotoxicity caused by CsA.

Secretion of a soluble T cell promoting factor by the human prostate adenocarcinoma cell line DU-145

INTRODUCTION

A variety of cancers suppress host immune defenses by secretion of soluble factors. Conditioned media (CM) from numerous cancer cell lines possess the ability to suppress proliferation of activated T cells. The effects of CM from the prostate cancer cell line DU-145 on T cell activation was investigated.

MATERIALS AND METHODS

Human PBMC, purified T cells and Jurkat T cells were treated with DU-145 CM. Proliferation, cell cycle, apoptosis, Fas expression/and cytokine secretion were assessed by thymidine incorporation, flow cytometry and ELISA.

RESULTS

DU-145 CM increased proliferation of concanavalin-A (ConA) activated peripheral blood mononuclear cells (PBMC) increasing the percentage of cells in the S/G2 phase of cell cycle. Treatment of the Jurkat T cell line with DU-145 CM induced a potent proliferative response. ConA-induced proliferation of purified T cells from human PBMC and murine splenocytes was augmented in a dose-dependent manner by addition of DU- 145 CM. DU- 145 CM treatment of ConA-activated T cells induced an increase in interleukin-2 (IL-2) production. The soluble factor(s) responsible for promoting T cell proliferation was dependent on protein synthesis by the DU- 145 cells and possessed a molecular weight greater than 10 kDa.

CONCLUSION

DU- 145 cells secrete a soluble factor(s) > 10 kDa, whose production is dependent on protein synthesis and which acts as a promoter of T cell activation.

[Extraction of MUAP from NEMG signal using self-organization competing NN]

The pattern classification of motor unit action potential (MUAP) of needle electrode electromyogram (NEMG) signal by means of self-organization competing Neural Network(NN) has been accomplished in this paper. The parameters and the power of excited white-noise of auto-regressive (AR) model are taken as the feature of MUAP. The results of simulated NEMG and real NEMG all show that this method of classification is very effective and correct, and thus it presents a new approach to the extraction of MUAP template in the study of decomposition of NEMG.

Metal-mediated self-assembly of pyridylcalixarenes: prevention of intramolecular metal chelation is essential in constructing molecular capsules

To construct calixarene-based molecular capsules utilizing the pyridyl-Pd(II) interaction, reactions of cone-pyridylcalix[4]arene 3, cone-pyridylcalix[5]arene 13, and cone-pyridylcalix[4]arene bis-crown 16 with square-planar Pd(II) complex 7 were investigated. Because of the coexistence of intermolecular binding and chelate-forming intramolecular binding, the reactions of cone-pyridylcalix[4]arene 3 or cone-pyridylcalix[5]arene 13 with cis-Pd(II) complex 7 yield complicated, structure-unknown oligomers. The short dioxyethylene bridges on the lower rim of pyridylcalix[4]arene bis-crown 16 rigidify the cone conformation and thus prohibit 16 from the intramolecular binding with a metal component. Thus, two cone-tetrapyridylcalix[4]arene bis-crown 16 and four cis-Pd(II) complex molecules self-assemble into molecular capsules that exist as a parallel/antiparallel conformer mixture in a nearly 1:1 ratio. The results demonstrated that to prevent entropically favorable intramolecular binding is essential is constructing higher capsule-like structures with calixarene building blocks by self-assembling.

Specific binding of proinsulin C-peptide to intact and to detergent-solubilized human skin fibroblasts

Proinsulin C-peptide exerts physiological effects on kidney and nerve function, but the mechanisms involved remain incompletely understood. Using fluorescence correlation spectroscopy, we have studied binding of rhodamine-labelled human C-peptide to intact human skin fibroblasts and to detergent-solubilised extracts of fibroblasts, K-562, and IEC-6 cells. Specificity was shown by displacement of rhodamine-labelled human C-peptide with unlabelled human C-peptide. C-peptide was found to bind to the cell membranes of intact fibroblasts with an association constant of 3 x 10(9) M(-1), giving full saturation at about 0.9 nM, close to the physiological C-peptide plasma concentration. Treatment of all investigated cells with the zwitter-ionic detergent Chaps was found to release macromolecules that bind specifically to C-peptide. The binding in Chaps extracts of fibroblasts was sensitive to time but remained reproducible for up to 2 h at room temperature. Lysophosphatidylcholine, Triton X-100, beta-octylglucopyranoside, SDS, or cholate gave extracts with only low or nonspecific binding. It is concluded that C-peptide binding components can be solubilised from cells, and that Chaps appears to be a suitable detergent.

Gene delivery of Cu/Zn-superoxide dismutase improves graft function after transplantation of fatty livers in the rat

Oxygen-derived free radicals play a central role in reperfusion injury after organ transplantation, and fatty livers are particularly susceptible. Endogenous radical scavengers such as superoxide dismutase (SOD) degrade these radicals; however, SOD is destroyed rapidly when given exogenously. Therefore, an adenoviral vector encoding the Cu/Zn-SOD gene (Ad.SOD1) was used here to test the hypothesis that organ injury would be reduced and survival increased in a rat model of transplantation of fatty livers. Donors received chow diet (untreated), high-fat diet, or ethanol-containing high-fat diet. Some of the ethanol-fed donors were infected either with the gene lacZ encoding bacterial beta-galactosidase (Ad.lacZ), or Ad.SOD1. After liver transplantation, SOD activity and protein expression in liver, survival, histopathology, release of transaminases, free radical adducts in bile, and activation of NF-kappaB, IkappaB kinase (IKK), Jun-N-terminal kinase (JNK), and TNFalpha were evaluated. Ad.SOD1 treatment increased survival dramatically, blunted transaminase release, and reduced necrosis and apoptosis significantly. Free radical adducts were increased two-fold in the ethanol group compared with untreated controls. Ad. SOD1 blunted this increase and reduced the activation of NF-kappaB. However, release of TNFalpha was not affected. Ad.SOD1 also blunted JNK activity after transplantation. This study shows that gene therapy with Ad.SOD1 protects marginal livers from failure after transplantation because of decreased oxygen radical production. Genetic modification of fatty livers using viral vectors represents a new approach to protect marginal grafts against primary nonfunction.

[Effect of combined operation including splenorenal shunt as the main technique for portal hypertension in children]

OBJECTIVE

To assess the effect of combined operation including splenorenal shunt as the main technique for portal hypertension in children.

METHODS

22 patients were reviewed and followed up from 1980 to 1998 (13 male, 9 female). The average age was 9.45 years. Intrahepatic type was shown in 16 patients and prehepatic type in 6. All patients had hematemesis, hematochezia or severe esophageal varices. Liver function was classified Child A in 14 patients, B in 7, and C in 1. Combined operation was performed in all patients.

RESULTS

There was no operative death in this group. 21 patients (95.5%) were followed up, with the longest time for 19 years (average 9.58 years). Six patients had hemorrhage from the esophageal varices after operation, and two died of hemorrhage. The survival rates of < 3, -5, -10, -15, > 15 years were 95.2%, 100%, 93.8%, 100%, 100% respectively. No hepatic encephalopathy was noted.

CONCLUSION

In treating and preventing hemorrhage from the esophageal varices, combined operation including splenorenal shunt as the main technique is the first choice for the portal hypertension in children. Attention must be paid to the patients who had hemorrhage from the esophageal varices after operation.

Using a prism to reject or select harmonic reflections in an X-ray monochromator

The angle by which an X-ray deviates from its original direction when it passes through a refractive prism is proportional to the square of the X-ray wavelength. This effect was used to discriminate between different harmonic orders of a two-crystal non-dispersive monochromator. Two cases are discussed. In the first case, a refractive prism allows tuning of the silicon 333 reflection to the peak of its double-crystal rocking curve while the higher-order harmonics are suppressed, with much of the harmonic rejection being controllable by the angle of the prism. In the second case, it is demonstrated that slightly tuning the second crystal of the monochromator allows the selection of a specific harmonic order from among reflections 333, 444 and 555.

Kupffer cell-derived prostaglandin E(2) is involved in alcohol-induced fat accumulation in rat liver

Destruction of Kupffer cells with gadolinium chloride (GdCl(3)) and intestinal sterilization with antibiotics diminished ethanol-induced steatosis in the enteral ethanol feeding model. However, mechanisms of ethanol-induced fatty liver remain unclear. Accordingly, the role of Kupffer cells in ethanol-induced fat accumulation was studied. Rats were given ethanol (5 g/kg body wt) intragastrically, and tissue triglycerides were measured enzymatically. Kupffer cells were isolated 0-24 h after ethanol, and PGE(2) production was measured by ELISA, whereas inducible cyclooxygenase (COX-2) mRNA was detected by RT-PCR. As expected, ethanol increased liver triglycerides about threefold. This increase was blunted by antibiotics, GdCl(3), the dihydropyridine-type Ca(2+) channel blocker nimodipine, and the COX inhibitor indomethacin. Ethanol also increased PGE(2) production by Kupffer cells about threefold. This increase was also blunted significantly by antibiotics, nimodipine, and indomethacin. Furthermore, tissue triglycerides were increased about threefold by PGE(2) treatment in vivo as well as by a PGE(2) EP(2)/EP(4) receptor agonist, whereas an EP(1)/EP(3) agonist had no effect. Moreover, permeable cAMP analogs also increased triglyceride content in the liver significantly. We conclude that PGE(2) derived from Kupffer cells, which are activated by ethanol, interacts with prostanoid receptors on hepatocytes to increase cAMP, which causes triglyceride accumulation in the liver. This mechanism is one of many involved in fatty liver caused by ethanol.

[Direct determination of rare earth elements in rare earth chloride and light rare earth oxide by ICP-AES]

ICP-AES was used for the direct determination of 15 rare earth elements in synthetic solutions and real sample. Spectral interferences between REEs in the mixtures of rare earth were investigated with a high-resolution echelle spectrometer and suitable analytical lines of 15 rare earth elements were selected. The Multicomponent Spectral Fitting(MSF) models were made. The method was used to remove spectral interferences and background. The factors influence the modes were discussed. The influences of acidity and ICP parameters were investigated. The compromise condition of simultaneous determination of 15 REEs was selected. Axially viewed ICP torch was used to determine 15 REEs, The detection limits are Y 0.21 microgram.L-1, La 9.1 micrograms.L-1, Ce 14.1 micrograms.L-1, Pr 1.9 micrograms.L-1, Nd 7.8 micrograms.L-1, Tm 0.37 microgram.L-1, Yb 0.12, Lu microgram.L-1, Ho 0.06 microgram.L-1, Er 0.06 microgram.L-1, Tb 0.53 microgram.L-1, Sm 1.14 micrograms.L-1, Eu 0.09 microgram.L-1, Dy 0.08 microgram.L-1, Gd 0.30 microgram.L-1. The recoveries of this procedure are between 98.4% and 101.7%. The RSD is within 2%. The method is rapid and accuracy.

Blood transfusion administration in seriously ill patients: an evaluation of SUPPORT data. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments

BACKGROUND

Administration of blood transfusion in seriously ill patients is highly variable. Limited data are available to guide transfusion decisions.

OBJECTIVE

To explore characteristics of patients who received blood transfusions and decisions to forego transfusions in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).

DESIGN

Prospective study of preferences, decision-making, and outcomes.

SETTING

Five teaching hospitals.

PARTICIPANTS

9105 patients aged 18 years and older meeting defined diagnostic and illness severity criteria.

MEASUREMENT

Data included blood transfusions, demographic characteristics, diagnoses, comorbid conditions, acute physiology score (APS), nutritional support, and functional status before hospitalization.

RESULTS

A total of 2863 patients (31.4%) received blood transfusions, usually early in their hospitalization. Transfused patients were more likely male (57.3 %; P = .008), with a younger mean age (56 vs 64 years), significantly higher APS (P < .001), and significantly lower 2- and 6-month survival predictions (P < .001). The patients with acute respiratory failure or multiorgan system failure with sepsis (1714; 59.9% of all patients receiving transfusions), multiorgan system failure with malignancy (480, 16.8%), and cirrhosis (248, 8.7%) were more likely to receive blood than those with other diseases. Few patients made a decision not to receive blood before (5; 0.05%) or after (126; 1.4%) study entry. Most patients with decisions to forego transfusions also had decisions against trying resuscitation.

CONCLUSIONS

Most transfusions occurred in patients with acute respiratory or multiorgan system failure. Few patients decide to forego transfusions. Additional investigation is necessary to evaluate blood transfusion practices in seriously ill patients.

The effects of patient race on outcomes in seriously ill patients in SUPPORT: an overview of economic impact, medical intervention, and end-of-life decisions. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments

BACKGROUND

Black Americans have significantly lower life expectancy than white Americans. Racial differences in medical access, management, and DNR orders have been documented.

OBJECTIVE

To review the effects of patient race on intervention and end-of-life decisions in seriously ill patients in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT).

DESIGN

Review of published analyses from SUPPORT.

SETTING

Five teaching hospitals

PARTICIPANTS

A total of 9105 patients aged 18 years or older (15% black race) meeting diagnostic and illness severity criteria.

MEASUREMENT

Analysis of data collected by chart abstraction and interviews.

RESULTS

Blacks reported significant loss in savings, although adjusting for diagnosis and disease severity did not demonstrate significant racial differences. Economic hardship was associated with a preference for comfort care, except in black patients (OR 0.71; CI 95%, 0.57-0.88). Blacks received less intervention with no significant difference in survival. Pain level and control were not affected by race. Blacks were more likely to want CPR, although adjustment for self-pay or Medicaid eliminated racial differences. Blacks were more likely to continue to prefer CPR 2 months after hospitalization (28% vs 17%) and were more likely to change a DNR order to preferring CPR (40 vs 27%). Blacks also more frequently wished to discuss CPR preferences with their physicians but were less likely to have this type of communication (OR 1.53; CI 95%, 1.11-2.11).

CONCLUSIONS

Patient race may impact on medical intervention and preferences in seriously ill patients. However, in this population, the differences are of modest clinical importance.

Dying with cancer: patients' function, symptoms, and care preferences as death approaches

OBJECTIVE

To characterize the dying experience of patients with cancer over the last 6 months of life.

STUDY DESIGN

A retrospective analysis of the last 6 months of life among patients with colon cancer and non-small cell lung cancer enrolled in a prospective cohort study from June 1989 to June 1991 and from January 1992 to January 1994.

SETTING

Five geographically diverse tertiary care academic medical centers participating in the Study to Understand Patient Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT) Project.

PARTICIPANTS

All patients enrolled in SUPPORT who had either colon cancer, metastatic to the liver or stage III or stage IV non-small cell lung cancer and died within 1 year of their index hospitalization. This report examines 316 of 520 patients with metastatic colon cancer and 747 of 939 patients with lung cancer enrolled in SUPPORT.

METHODS

Data were collected by interview and chart abstraction at several time points in the SUPPORT Project. To describe progression to death, we constructed four observational windows backward in time beginning with patients' date of death and ending with their date of entry into the SUPPORT Project or 6 months before their death, whichever came first: (1) 3 days before death, (2) 3 days to 1 month before death, (3) 1 month to 3 months before death, and (4) 3 months to 6 months before death. For each outcome, patients contributed information to all windows during which they had data collected. We describe the frequency distributions of each outcome over time and report tests for trend.

OUTCOME MEASURES

We examined several outcomes over time, including: percentage of days spent in a hospital; prognosis as measured by model-based prognostic estimates of 6-month survival; severity of illness as measured by the acute physiology score; functional status as measured by dependencies in activities of daily living (ADLs); severe physical and emotional symptoms, including pain, depression, and anxiety; patients' preferences for care; and the financial impact on patients' families.

RESULTS

The death rate within 1 year of study entry was high among patients with metastatic colon cancer and advanced non-small cell lung cancer enrolled in SUPPORT (61% and 80%, respectively). As patients with cancer progress toward death, their estimated 6-month prognosis decreases significantly and the severity of their disease worsens. Patients' functional status also declines significantly as they approach death, such that most patients have four or more impairments within the 3 days before death. Patients with cancer experience significantly more pain and confusion as death approaches. Severe pain is common; more than one-quarter of patients with cancer experience serious pain 3 to 6 months before death and more than 40% were in serious pain during their last 3 days of life. However, dying patients are only modestly depressed and anxious during their last 3 days of life. As death approaches, patients favor comfort measures over life-extension, and about two-thirds want to forego resuscitation within 3 days of death. Families of patients dying with cancer incurred significant financial burdens during the last 6 months of life, and much of this burden was already experienced by 3 to 6 months before death.

CONCLUSIONS

The last 6 months of life for patients with cancer is characterized by functional decline and poorly controlled severe pain and confusion. Although patients increasingly prefer comfort care as they near death, many die in severe pain. These findings highlight important opportunities to improve the quality of care at the end of life for patients dying with cancer.

Dying with end stage liver disease with cirrhosis: insights from SUPPORT. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment

OBJECTIVES

To understand patterns of care and end-of-life preferences for patients dying with end stage liver disease with cirrhosis (ESLDC).

METHODS

Data were collected during the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment (SUPPORT), a prospective cohort study of seriously ill hospitalized adults at five teaching hospitals in the United States, and included all patients enrolled in SUPPORT with ESLDC.

RESULTS

Of 575 patients with ESLDC, 166 died during index hospitalization, and 168 died in the following year. The majority were male (65%) and white (80%); the median age was 52 years. Most rated their quality of life as poor or fair, and multiple comorbidities were common. Most spent their last few days completely disabled. Families often reported loss of most income and the need to leave work or other activities in order to care for patients. Pain was at least moderately severe most of the time in one-third of patients. End-of-life preferences were not associated with survival. Most patients (66.8%) preferred CPR, but DNR orders and orders against ventilator use increased near death.

CONCLUSIONS

Patients with liver disease were young, likely to be male, and often had low incomes. The high burden of pain was comparable to that reported for patients with lung and colon cancer. Persons dying with liver disease may benefit from increased attention to relief of symptoms, improved home care, and advanced care planning.

Patients who want their family and physician to make resuscitation decisions for them: observations from SUPPORT and HELP. Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment. Hospitalized Elderly Longitudinal Project

OBJECTIVE

To determine the extent to which older or seriously ill inpatients would prefer to have their family and physician make resuscitation decisions for them rather than having their own stated preferences followed if they were unable to decide themselves.

DESIGN

Analysis of existing data from the Hospitalized Elderly Longitudinal Project (HELP) and the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatment (SUPPORT).

SETTING

Five teaching hospitals in the United States.

PARTICIPANTS

2203 seriously ill adult inpatients (SUPPORT) and 1226 older inpatients (HELP) who expressed preferences about resuscitation and about advance decision-making.

MEASURES

We used a logistic regression model to determine which factors predicted preferences for family and physician decision-making.

RESULTS

Of the 513 HELP patients in this analysis, 363 (70.8%) would prefer to have their family and physician make resuscitation decisions for them whereas 29.2% would prefer to have their own stated preferences followed if they were to lose decision-making capacity. Of the 646 SUPPORT patients, 504 (78.0%) would prefer to have their family and physician decide and 22.0% would prefer to have their advance preferences followed. Independent predictors of preference for family and physician decision-making included not wanting to be resuscitated and having a surrogate decision-maker.

CONCLUSIONS

Most inpatients who are older or have serious illnesses would not want their stated resuscitation preferences followed if they were to lose decision-making capacity. Most patients in both groups would prefer that their family and physician make resuscitation decisions for them. These results underscore the need to understand resuscitation preferences within a broader context of patient values.