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Small cell lung cancer (SCLC) is a highly lethal subtype of lung cancer with a particularly poor prognosis. For decades, the best available systemic therapy was platinum plus etoposide chemotherapy, which offered frequent but transient responses. Survival gains were finally realized with the addition of immune checkpoint inhibitors to first-line chemotherapy. The phase III IMpower 133 trial showed that the addition of atezolizumab to chemotherapy improved survival. The subsequent CASPIAN trial demonstrated a similar benefit with durvalumab. These results quickly established chemo-immunotherapy as the preferred initial treatment for advanced SCLC, but outcomes remain poor for most patients. Here, we review the current and evolving role of immunotherapy in SCLC and outline emerging strategies poised to further elevate the standard of care.

Resume Contexte Differentes mesures de l’utilisation des antimicrobiens assurent leur bon usage, dans le cadre d’un programme d’antibiogouvernance (aussi appele programme de gerance des antimicrobiens). Objectif L’objectif principal de cette etude etait de decrire la consommation d’antibiotiques au sein d’un etablissement universitaire mere-enfant en utilisant la classification AWaRe sur une periode 15 ans. Methode L’etude descriptive et retrospective a inclus toutes les donnees de consommations d’antibiotiques des patients admis dans un centre hospitalier universitaire mere-enfant du 1er avril 2005 au 31 mars 2021. Des 180 denominations communes d’antibiotiques proposees par l’Organisation mondiale de la sante (OMS), 54 etaient utilisees. Le nombre de jours de traitement (JT) par 1000 jours-presence (JP) a ete calcule par annee, par patientele (chirurgie, pediatrie, oncologie, soins intensifs, soins intensifs neonataux, pouponniere, psychiatrie, readaptation et obstetrique-gynecologie) et de facon globale. Les donnees ont ete classees selon les trois groupes AWaRe de l’OMS. Resultats Un total de 10 489 JT/1000JP a ete collecte sur 15 ans, soit 53,9 % du groupe « Access », 45,2 % du groupe « Watch » et 0,9 % du groupe « Reserve ». Sur 15 ans, on note une faible reduction du recours aux antibiotiques. Le rapport des valeurs de consommation en JT/1000JP de 2020-2021 sur celles de 2005-2006 etait de 0,84 globalement (4743/5653), 0,79 pour le groupe « Access » (286/361), 0,89 pour le groupe « Watch » (270/302) et 0,88 pour le groupe « Reserve » (2,1/2,4). Conclusion La classification AWaRe a ete utilisee afin de decrire la consommation d’antibiotiques au sein d’un centre mere-enfant. La consommation du centre hospitalier etudie se compare avantageusement aux donnees internationales et s’approche des cibles de l’OMS. Cette position peut etre liee a la presence d’un programme structure d’antibiogouvernance mis en place depuis plusieurs annees au sein de notre etablissement. D’autres travaux sont necessaires afin de cibler plus finement les antibiotiques devant profiter d’un meilleur encadrement.

An important question is whether consensus mechanisms for copper monooxygenase enzymes such as peptidylglycine monooxygenase (PHM) and dopamine β-monooxygenase (DBM) generated via computational and spectroscopic approaches account for important experimental observations. We examine this question in the light of recent crystallographic and QMMM reports which suggest that alternative mechanisms involving an open to closed conformational cycle may be more representative of a number of experimental findings that remain unaccounted for in the canonical mononuclear mechanisms. These include (i) the almost negligible reactivity of the catalytic copper site (CuM) with oxygen in the absence of substrate, (ii) the carbonyl chemistry and in particular the substrate-induced activation exemplified by the lowered CO stretching frequency, (iii) the peroxide shunt chemistry which demands an intermediate that facilitates equilibrium between a Cu(II)-peroxo state and a Cu(I)-dioxygen state, and (iv) clear evidence for both closed and open conformational states in both PHM and DBM. An alternative mechanism involving a dinuclear copper intermediate formed via an open to closed conformational transition appears better able to accommodate these experimental observations, as well as being shown by QMMM methodologies to be energetically feasible. This suggests that future experiments should be designed to distinguish between these competing mechanisms and the factors that govern the oxygen reactivity of the copper centers. In particular, determining how oxygen reactivity is activated by binding of substrate, should be considered an important new challenge.

Background Hip fracture is one of the most common injuries in adults and can be a life changing experience for most. Many patients are ill-prepared for the changes in their normal daily activity that often occur in the following months after surgery. Community rehabilitation services vary, as management often focuses on acute over community services. This can impact on the patient’s experience post hip fracture. Objectives The aim of this review was to understand and examine patients’ perspective, views and experiences of physiotherapy rehabilitation in the community after hip fracture surgery, to improve future clinical practice for this population. Design A qualitative thematic synthesis was undertaken to investigate the aim. A content thematic analysis approach was used to analyse the qualitative data. Data sources A systematic search was carried out of the following databases: CINAHL, PEDro, PubMed, Whiley Online, AMED & CINAHL. Further searches were performed in Google Scholar and backwards citation was used to search within included studies. Study selection A review of qualitative studies was performed using the SPIDER tool for identification of suitable studies and the CASP tool for analysis of quality. Studies were included if they were qualitative or part qualitative and involved patients’ perceptions of rehabilitation after hip fracture following hospital discharge. Results Full text review was performed on 35 studies of which, 10 were identified as suitable. Three key themes were identified regarding experiences of rehabilitation within the community after hip fracture: Engaging in physical activity; Maintaining a positive perspective, and Support. Conclusion Findings support the need for the patient perspective and experience to be considered in the improvement of hip fracture care pathways regarding rehabilitation in the community setting after hip fracture. This can help identify key areas of improvement in rehabilitation to enhance and improve the patient journey after hip fracture. Systematic Review Registration Number PROSPERO CRD42018095434.

Laser scabbling of concrete is a process by which the surface layer of concrete is removed through the use of a high power (low power density) laser beam. In order to understand how the age and treatment of structures may affect the laser scabbling process, the aim of the research presented in this paper was to establish a relationship between laser interaction time, surface temperature and volume removal for cementitious materials of different ages and different degrees of saturation. The investigation focussed on (i) the effect of age on saturated specimens and (ii) the effect of prolonged drying. The results show that drying of specimens had the largest effect on scabbling. The effect of age on saturated specimens was small for PFA + OPC pastes, mortars and concretes, but significant for OPC pastes, where the volume of scabbling dramatically reduced with age.

Previous studies of a synthesis of phomactin A had resulted in the synthesis of a 15-methylenebicyclo[9.3.1]pentadecadiene. The next step in the synthesis was to be the epoxidation of this methylenecyclohexane that was hoped would lead to a 1-(hydroxymethyl)cyclohexene by rearrangement of the exocyclic epoxide, but the epoxidation was difficult to carry out regioselectively on advanced intermediates. However, oxidation of a 15-methylenebicyclo[9.3.1]pentadeca-3,7-dien-14-ol using tetra-n-propylammonium perruthenate and N-methylmorpholine-N-oxide led to conversion of this homoallylic alcohol into the corresponding 14-oxobicyclo[9.3.1]pentadeca-1(15),3,7-triene-15-carboxaldehyde in one step. Reduction of this using DIBAL-H gave a promising intermediate for a synthesis of a phomactin. The scope of this oxidation of homoallylic alcohols was briefly investigated.

Industrial activity periodically experiences breakthrough innovations in energy efficiency, but the estimated impacts of these innovations on aggregate energy use are highly varied. We develop a general equilibrium model to show this variation is in part determined by the structure of the economy’s input–output network. Our results show industrial energy efficiency improvements affect aggregate energy use through adjustments in factor and commodity markets, and a process of structural transformation that alters the way energy is used and produced in the economy. We describe the aggregate impact of these processes using new energy centrality concepts that measure the extent to which an industry implicitly produces or consumes energy resources. In a calibrated simulation, we find variation in these energy centrality concepts explains between 38 and 92% of variation in the rebound effect, which suggests input–output structure is a critical determinant of the aggregate effects of energy efficiency.

The expansion of distributed solar necessitates additional research into the impacts on both utilities and their customers. In this paper we use New Jersey solar data, PJM market data, and demand profiles from a PJM utility to investigate rate and bill impacts of large-scale solar penetration. In addition to the subsidization of solar adopters by non-participants, we highlight the channels through which cross-subsidization of rate classes can arise in practice. The results of our study indicate that the fear of a utility “death spiral” may be exaggerated. Significant solar can be incorporated with only a 2% increase in non-participant bills. At high levels of penetration, distributed solar has the potential to alter the system peak hour which affects the allocation of costs across rate-classes. As the peak hour shifts to the evening when solar production diminishes, residential customers face higher distribution costs. Policy makers and utilities need to be aware of these challenges in designing the next generation of rates that are better aligned with cost causality.

Objectives To investigate seasonal injury incidence and musculoskeletal screening as a predictor of injury in elite Olympic class sailors. Design Prospective cohort study. Methods A 12-month analysis of injury surveillance data was performed for elite Australian sailors (age = 16–30 years, N = 22). Pre-season musculoskeletal screening (incorporating mobility, stability and neural tests) and seasonal injury data were analysed for predictive relationships, and associations between potential predictor variables and injury status. Results Injuries requiring medical attention occurred at a rate of 3.6 injuries/athlete, while injuries resulting in disability occurred at a rate of 0.6 injuries/athlete, with the lumbar spine the main site of injury (23% and 33%, respectively). Wrist and hand injury resulted in the highest number of days of disability (110 days), followed by injury to the lumbar spine (87 days). Across the season 75% of injuries to the lumbar spine occurred in the latter half of the season. The only screening measure predictive of injured/uninjured status was better left-sided single-leg decline-squat performance (OR = 0.29; 95% CI = 0.09–0.88; p = 0.03), while increasing age was significantly (p = 0.03) associated with thoracic (OR = 1.48; 95% CI = 1.03–2.12) and lumbar spine (OR = 1.46; 95% CI = 1.04–2.04) injury. Conclusions Though clinically useful, current screening protocols do not adequately assess the risk of seasonal injury in elite Olympic class sailors, and should be revised. Due to the increased risk of spinal injury and potential lost/modified participation in older Olympic class sailors, injury prevention activities should be individualised and age appropriate.

6-Halouridine derivatives were synthesized regiospecifically through the coupling of N3-protected 6-halouracil to a ribose derivative. The combination of the silylating reagent N,O -bis(trimethylsilyl)acetamide and Lewis acid catalyst trimethylsilyl trifluoromethanesulfonate is unique in their ability to facilitate the coupling of sterically hindered pyrimidine bases to ribose to form nucleoside derivatives.

To compare the outcomes of microcalcifications recalled on full-field digital (FFDM) and FFDM and combined tomosynthesis (Combo) to synthetic (SM) screening mammograms.We reviewed medical records, radiology, and pathology reports of all patients found to have abnormal calcifications requiring further evaluation on mammography screening at our institution between 11/1/2016-11/1/2018 and collected patient demographics, calcification morphology and distribution, and mammography technique (SM, FFDM, or Combo). We used biopsy pathology or at least 1-year imaging follow-up to establish overall diagnostic outcome (benign or malignant). Fisher's exact test was used to compare validation rates at diagnostic work-up, BI-RADS category, and final outcome of calcifications identified on each screening technique. T-test was used for continuous variables.Of 699 calcifications in 596 women recalled, 176 (30%) of 596 were from SM and 420 (70%) FFDM/Combo. There was a significantly higher rate of calcifications unvalidated at diagnostic work-up for SM compared to FFDM/Combo (0.8% vs. 10%, p0.0001). SM calcifications were more likely to receive BI-RADS 2/3 at diagnostic work-up compared to FFDM/Combo ones (55% vs. 42%, p = 0.003). Of 346 (49%) calcifications that underwent biopsy, 88 (25%) were malignant (36% of SM vs. 22% of FFDM/Combo, OR:0.5 [95% CI: 0.3, 0.8] p = 0.01). Of 622 lesions with established diagnostic outcome, there was no difference between having an overall benign or malignant outcome between SM and FFDM/Combo (17% vs. 13%, OR: 0.8 [95% Cl: 0.5, 1.2] p = 0.27).Synthetic tomosynthesis screening results in a higher rate of false positive and unvalidated calcification recalls compared to FFDM/Combo.

Copyright © 2016 The Author(s). Duplex stainless steel (DSS) is one of the materials of choice for structural and nuclear applications, having high strength and good corrosion resistance when compared with other grades of stainless steel. The welding process used to join these materials is critical as transformation of the microstructure during welding directly affects the material properties. High power laser welding has recently seen an increase in research interest as it offers both speed and flexibility. This paper presents an investigation into the important parameters affecting laser welding of DSS grade 2205, with particular focus given to the critical issue of phase transformation during welding. Bead-on-plate melt-run trials without filler material were performed on 6mm thick plates using a 5 kW Yb-fibre laser. The laser beam was characterized and a Design of Experiment approach was used to quantify the impact of the process parameters. Optical metallographic methods were used to examine the resulting microstructures.

On treatment with n-butyllithium, 4-alkoxy- and 4-silyloxy-2-(tributylstannylmethoxymethyl)-1,6-dimethyl-1-(phenylsulfonylmethyl)cyclohex-2-enes undergo tin–lithium exchange followed by [2,3]-Wittig rearrangements to give 3-alkoxy- and 3-silyloxy-2-hydroxymethyl-5,6-dimethyl-1-methylene-6-(phenylsulfonylmethyl)cyclohexanes in which the 2-hydroxymethyl and 6-phenylsulfonylmethyl residues are cis-disposed about the six-membered ring. In contrast, the corresponding 1-(phenylsulfanylmethyl)cyclohexenes give mainly methylenecyclohexanes with the 2-hydroxymethyl and 6-phenylsulfanylmethyl groups trans-disposed about the six-membered ring. This stereoselectivity is independent of the nature of the alkoxy- or silyloxy-substituent and configuration at C4. The 3-tert-butyldiphenylsilyloxy-1-methylene-6-(phenylsulfonylmethyl)cyclohexane was converted into a macrocyclic precursor of the phomactins.

We discuss a geometric error model for those large volume laser scanners that have the laser source and a spinning prism mirror mounted on a platform that can rotate about the vertical axis. We describe the terms that constitute the model, address their effect on measured range and angles, and discuss the sensitivity of different two-face and volumetric length tests to each term in the model. We report on experiments performed using commercially available contrast targets to assess the validity of the proposed model. Geometric error models are important not only in improving the accuracy of laser scanners, but also in facilitating the identification of test procedures for performance evaluation of these instruments and therefore in the development of documentary Standards. The work described in this paper lays the foundation for such efforts.

The copper-transporting ATPase ATP7A has an essential role in human physiology. ATP7A transfers the copper cofactor to metalloenzymes within the secretory pathway; inactivation of ATP7A results in an untreatable neurodegenerative disorder, Menkes disease. Presently, the mechanism of ATP7A-mediated copper release into the secretory pathway is not understood. We demonstrate that the characteristic His/Met-rich segment Met(672)-Pro(707) (HM-loop) that connects the first two transmembrane segments of ATP7A is important for copper release. Mutations within this loop do not prevent the ability of ATP7A to form a phosphorylated intermediate during ATP hydrolysis but inhibit subsequent dephosphorylation, a step associated with copper release. The HM-loop inserted into a scaffold protein forms two structurally distinct binding sites and coordinates copper in a mixed His-Met environment with an ∼2:1 stoichiometry. Binding of either copper or silver, a Cu(I) analog, induces structural changes in the loop. Mutations of 4 Met residues to Ile or two His-His pairs to Ala-Gly decrease affinity for copper. Altogether, the data suggest a two-step process, where copper released from the transport sites binds to the first His(Met)(2) site, triggering a structural change and binding to a second 2-coordinate His-His or His-Met site. We also show that copper binding within the HM-loop stabilizes Cu(I) and protects it from oxidation, which may further aid the transfer of copper from ATP7A to acceptor proteins. The mechanism of copper entry into the secretory pathway is discussed.

Computed tomographic (CT) scanning technology now employs up to 320 detector rows of 0.5-mm width and allows rapid acquisition of isotropic volume datasets over the entire body. Data from a single CT acquisition can be reconstructed into image series that would formerly have required multiple acquisitions. Small isotropic voxels permit scan parameters to be general while reconstruction algorithms remain specific to anatomy. While this results in more efficient operation in the Emergency Department, it necessitates new ways of displaying, interpreting, and archiving the information. Critical decisions include how much of the patient to scan and how to time contrast injections when imaging multiple organs. These choices must be made in light of dose considerations to the patient and the general population of patients. The technical basis of high-density CT scanning is discussed, including detector configurations and reconstruction techniques. Volumetric scanning in the Emergency Department can improve patient care but requires a change of technical habits.

Copper-transporting ATPase ATP7B is essential for human copper homeostasis and normal liver function. ATP7B has six N-terminal metal-binding domains (MBDs) that sense cytosolic copper levels and regulate ATP7B. The mechanism of copper sensing and signal integration from multiple MBDs is poorly understood. We show that MBDs communicate and that this communication determines the oxidation state and conformation of the entire N-terminal domain of ATP7B (N-ATP7B). Mutations of copper-coordinating Cys to Ala in any MBD (2, 3, 4, or 6) change the N-ATP7B conformation and have distinct functional consequences. Mutating MBD2 or MBD3 causes Cys oxidation in other MBDs and loss of copper binding. In contrast, mutation of MBD4 and MBD6 does not alter the redox status and function of other sites. Our results suggest that MBD2 and MBD3 work together to regulate access to other metal-binding sites, whereas MBD4 and MBD6 receive copper independently, downstream of MBD2 and MBD3. Unlike Ala substitutions, the Cys-to-Ser mutation in MBD2 preserves the conformation and reduced state of N-ATP7B, suggesting that hydrogen bonds contribute to interdomain communications. Tight coupling between MBDs suggests a mechanism by which small changes in individual sites (induced by copper binding or mutation) result in stabilization of distinct conformations of the entire N-ATP7B and altered exposure of sites for interactions with regulatory proteins.

The bicyclic sulfone 28, which has the intact carbon skeleton of phomactins, was prepared using a stereoselective [2,3]-Wittig Still rearrangement, a ytterbium triflate-mediated addition of a vinyllithium reagent to an aldehyde and macrocyclisation via an intramolecular sulfone alkylation, as key steps. During studies into the conversion of this intermediate into phomactin A, it was found that oxidation of homoallylic alcohols using TPAP can give unsaturated keto-aldehydes, and the stereoselectivity of reduction of a ketone at C(14) is influenced by the presence of a remote sulfonyl group at C(10).

Gram-negative bacteria utilize dual membrane resistance nodulation division-type efflux systems to export a variety of substrates. These systems contain an essential periplasmic component that is important for assembly of the protein complex. We show here that the periplasmic protein CusB from the Cus copper/silver efflux system has a critical role in Cu(I) and Ag(I) binding. Isothermal titration calorimetry experiments demonstrate that one Ag(I) ion is bound per CusB molecule with high affinity. X-ray absorption spectroscopy data indicate that the metal environment is an all-sulfur 3-coordinate environment. Candidates for the metal-coordinating residues were identified from sequence analysis, which showed four conserved methionine residues. Mutations of three of these methionine residues to isoleucine resulted in significant effects on CusB metal binding in vitro. Cells containing these CusB variants also show a decrease in their ability to grow on copper-containing plates, indicating an important functional role for metal binding by CusB. Gel filtration chromatography demonstrates that upon binding metal, CusB undergoes a conformational change to a more compact structure. Based on these structural and functional effects of metal binding, we propose that the periplasmic component of resistance nodulation division-type efflux systems plays an active role in export through substrate-linked conformational changes.

Proton NMR spectroscopy was used to investigate changes in composition of lipids in the liver, kidneys and adrenal glands of Meriones unguiculatus infected with Echinococcus multilocularis. It was found that all three organs of infected animals had less total glycerophospholipid and CH2 in the fatty acid (FA) component CHCH(CH2CHCH)n than the corresponding organs of uninfected animals. The concentrations of other lipids in these organs were variable in their response to infection. The livers of infected jirds had lower concentrations of phosphatidylcholine (PTC), phosphatidylinositol, cholesterol (CTL) and the FA component CH2CH2COO, but more phosphatidylethanolamine (PTE). Kidneys of infected animals had less PTC, PTE and arachidonic acid. The adrenal glands, which were most affected by E. multilocularis infection, had lower concentrations of PTE, CTL, total FA, triacylglycerol, linoleic acid, and the FA components CH2CH2COO, CH2COO, CH2 in (CH2)n, CHCH and CH2CHCH.

Two chromatographic forms of laccase c1 and c2 were purified approximately 225-fold from the extracellular culture fluid of ligninolytic cultures of Dichomitus squalens, using DEAE–Sepharose and Mono-Q fast protein liquid chromatography. Each homogeneous laccase (c1 and c2) has a molecular mass of approximately 66 kDa as determined by SDS–PAGE. Both forms are glycoproteins, and each contains four copper atoms per molecule of protein. The first 20 amino acids of the N-terminal sequences of these two laccases are identical and are similar to those of laccases from other lignin-degrading fungi. The electronic absorption spectra of these laccases exhibit bands at 610 and 330 nm, indicative of type I and type III copper. The EPR spectrum of laccase c1 exhibits bands indicative of type I and type II copper. Each laccase oxidizes a variety of phenolic substrates, has a pH optimum of 3.0 for the oxidation of 2,6-dimethoxyphenol, and is inhibited strongly by fluoride and azide.

Tribolium confosum beetles infected with metacestodes of Hymenolepis diminuta, Hymenolepis microstoma , or Hymenolepis nana were used to study the effect of parasitism on carbohydrate metabolism. 13 C NMR in vivo spectra of uninfected and infected T. confusum , fed d -[1- 13 C]glucose for 24 hr, showed resonances due to CH 3 , (CH 2 ) N , and C=C of fatty acids chains, C 1 , C 6 , and C 2-5 of trehalose and C 1 of glycogen. The 13 C NMR spectra of extracts of these beetles confirmed these assignments and revealed additional small peaks from C 1 of α-glucose, C 1 of β-glocose, C 6 of both αand β-glucose, and C 3 of alanine. The 1 H NMR spectra of these extracts showed resonances due to the same compounds and, in addition, resonances from betaine, cholines, succinate, acetate, and lactate. All infected beetles contained less glucose and lactate than uninfected controls. Furthermore, beetles infected with H. diminuta had less trehalose but more glycogen and those infected with H. microstoma had less succinate and acetate than controls.

1. 1. 1H NMR spectra of the duodenum, jejunum and ileum tissues of the small intestine of a rat showed metabolic gradients. 2. 2. The concentrations of metabolites in these gut regions were altered by the presence of the tapeworm Hymenolepis diminuta. 3. 3. In the infected duodenum there was significantly less glycogen, glucose and phosphocreatine/creatine, but significantly more lactate than in the corresponding controls. 4. 4. Infected jejunum contained significantly less betaine but significantly more succinate, alanine and lactate. 5. 5. Infected ileum had significantly less glycogen and taurine but significantly more alanine and lactate.

PURPOSE: To report a patient with an initial presentation of optic disk edema secondary to Propionibacterium acnes endophthalmitis. METHODS: Interventional case report. The patient had surgery and treatment related to endophthalmitis. Nine months after cataract surgery with posterior chamber lens implant, a 79-year-old man receiving topical corticosteroids in the same eye presented with best-corrected visual acuity of 20/60, a superior visual field defect, and optic nerve edema without intraocular inflammation. One year postoperatively, the eye presented a further decrease in best-corrected visual acuity, and a dense white plaque was noted on the posterior capsule. RESULTS: One year postoperatively, a partial capsulectomy with vitrectomy and injection of intravitreal antibiotics was performed. Hematoxylin and eosin stain of the posterior capsule plaque revealed gram-positive coccobacilli characteristic of P. acnes . CONCLUSION: Propionibacterium acnes endophthalmitis may present after cataract surgery with intraocular lens implant with decreased vision, optic disk edema, and a visual field defect.

This paper presents a comprehensive framework and methodology in an attempt to direct policy solutions to soil and water degradation from water-related soil erosion. The perspective adopted by this research is social science in nature. Past research on the adoption of soil conservation practices has tended to concentrate on the micro (individual) level of inquiry and has tended to ignore environmental (i.e. biophysical) factors. Previous models of the adoption of soil conservation practices are reviewed and critiqued. Based on the strengths and limitations of these approaches, a comprehensive analytical framework that identifies and relates micro (e.g. farm and farmer characteristics) and macro (e.g. institutional arrangements, fiscal and monetary policies, agricultural policies) factors influencing the adoption and continued use of soil conservation measures is proposed. It is hypothesized that economic and institutional constraints will exert the greatest influence on decisions to use land stewardship practices when problem awareness exists at the micro level. Based on this framework, a research methodology is developed to classify the farm population into relatively homogeneous sub-groups based on farmers' receptivity to the adoption and use of currently available and prospective conservation practices. These groupings could then form the basis for targeting a range of policies, programs, and other measures appropriate for each group.

In open chest anaesthetised dogs, dofetilide increased the ventricular effective refractory period over the dose range 1-100 micrograms/kg i.v. and the ventricular fibrillation threshold at doses between 3-100 micrograms/kg and was 80-1000 times more potent than sematilide, racemic sotalol, d-sotalol or quinidine. The maximal increases in ventricular fibrillation threshold induced by sematilide and quinidine were less than that induced by the other drugs. A change in the character of the induced arrhythmia from true ventricular fibrillation to a rapid ventricular flutter, with frequent spontaneous conversion, was observed following all drugs. No adverse haemodynamic effects of dofetilide, sematilide or d-sotalol were observed, but quinidine induced marked cardiac depression and racemic sotalol also impaired left ventricular contractility. All drugs reduced heart rate, though the effect of racemic sotalol was clearly greater than that of the other agents. Dofetilide is a potent class III antiarrhythmic agent with antifibrillatory properties and a favourable haemodynamic profile.

Copper uptake proteins (CTRs), mediate cellular acquisition of the essential metal copper in all eukaryotes. Using electron cryomicroscopy, we determined a 3D-structure of hCTR1 at ∼7A resolution. The structure suggests that CTR1 proteins transport copper through a movement of Cu(I)-ions between defined binding sites and that intracellular copper chaperones are capable of directly obtaining copper from CTR1. To test these ideas, we used EXAFS to determine copper binding sites in hCTR1. We find that trimeric hCTR1 can stably bind 2 Cu(I)-ions through 3-coordinate Cu-S bonds. Moreover, EXAFS data obtained using Se-Cys-labeled CCS is consistent with the idea that the chaperone can obtain Cu(I) directly from copper loaded hCTR1. Modeling of a hypothetical hCTR1-CCS complex furthermore suggests that CCS may be able to associate with the membrane. Such a partitioning would greatly increase the efficiency of copper transfer to the chaperone because it would allow CCS to find hCTR1 through a 2D-diffusional search rather than a 3D-random walk. In support of this idea, we find that hCCS can bind to bilayers in vitro. Lastly, we generated a C-alpha model of the membrane embedded region of hCTR1 to aid future mechanistic studies. The model is consistent with the results of an extensive Trp-scan analysis of the membrane domain of hCTR1 and yCTR3 in that the overwhelming majority of residues found to be structurally and/or functionally important participate in helix packing interactions or face the copper permeation pathway along the 3-fold axis the CTR trimer.

The structure of the copper sites in oxidized and reduced dopamine beta-hydroxylase has been studied by extended x-ray absorption fine structure spectroscopy using a restrained refinement approach to data analysis. An histidine-rich active site has been found to be present with an average histidine coordination of between two and three histidine ligands per copper. In the oxidized protein, the data support four-coordination, involving two to three imidazole groups at 1.99 A with additional ligands derived from water or exogenous O-donor groups at an average distance of 1.94 A. Studies on the reduced enzyme have focused on resolving the controversy in the literature (Scott, R. A., Sullivan, R. J., De Wolfe, W. E., Dolle, R. E., and Kruse, L. I. (1988) Biochemistry 27, 5411-5417; Blumberg, W. E., Desai, P. R., Powers, L., Freedman, J. H., and Villafranca, J. J. (1989) J. Biol. Chem. 264, 6029-6032) as to whether a S/Cl scatterer is a ligand to Cu(I). Five independent samples of reduced enzyme prepared under conditions designed to probe the Cu(I) ligand environment have been measured and analyzed. All five samples gave identical spectra and could be simulated by two to three imidazoles (1.93 A) and 0.5 S/Cl (2.25 A) per Cu(I). The spectra were insensitive to the presence of added bromide or to exclusion of chloride during preparation. The results establish that the heavy atom scatterer is derived from a sulfur donor. Some evidence was found for an additional O/N scatterer at 2.6 A in the reduced enzyme. A hypothesis for the structure of the copper sites has been proposed involving inequivalent CuA(His)3(H2O)...CuB-(His)2X(H2O) coordination in the oxidized enzyme, which upon reduction loses coordinated water and coordinates a sulfur probably from a methionine.

The carbon monoxide complex of ascorbate-reduced dopamine beta-hydroxylase has been prepared and characterized by Fourier transform infrared, fluorescence, and x-ray absorption spectroscopies. CO has previously been shown to be a competitive inhibitor with respect to O2, and binds to only one of the two copper atoms/active site (Blackburn, N. J., Pettingill, T. M., Seagraves, K. S., and Shigeta, R. T. (1990) J. Biol. Chem. 265, 15383-15386). Thus, it acts as an excellent probe of the O2-binding site. A single C-O infrared absorption band is observed at 2089 cm-1, shifting by 46 cm-1 to lower energy on substitution with either 13C16O or 12C18O. The 13C isotope shift is reversed to the position expected for 12CO upon vacuum flushing with 12CO gas, indicating that formation of the CO adduct is a fully reversible process. Binding of the substrate tyramine does not eliminate the infrared peak but causes a 3-cm-1 shift to lower energy. On the other hand, binding of a bifunctional inhibitor which cross-links the substrate and O2-binding site does eliminate the CO peak. These data, in conjunction with the competitive nature of CO binding with respect to O2, identify the CO-binding site as the O2-binding site, and place it in close proximity to the substrate-binding site. CO-dopamine beta-hydroxylase exhibits no luminescence in the visible region, suggesting a structure different from carbonmonoxy hemocyanin, and in all probability mononuclear. Analysis of extended x-ray absorption spectroscopy data is most consistent with an average coordination per Cu of 2-3 histidines, 0.5 CO, and 0.5 S atoms as ligands, and absorption edge comparisons indicates pseudo-4 coordination as the most likely geometry at each Cu(I) center. The results can be interpreted by a model involving inequivalent 4-coordination at each Cu(I) center in the CO adduct with CuAHis3S...CuBHis2CO-X as the coordination most consistent with all of the data.

The direct effects of the inflammatory mediators, histamine (HI) and serotonin (SE), on the glucose metabolism of Hymenolepis diminuta in vitro were studied by analyzing the excretory products from culture media, containing d - 1 - 13 C-glucose and various concentrations of HI and/or SE, by 1 H-nuclear magnetic resonance (n.m.r.) spectroscopy. The results revealed that HI markedly accelerated the glycolysis process by increasing the amount of lactate production. The increased glycolytic activity was reflected in a concentration-dependent increase in glucose uptake. Excretion of acetate was also stimulated by HI. A low concentration of SE significantly increased succinate, acetate and lactate excretions, whereas a high concentration had little effect on lactate production and significantly decreased succinate and acetate excretions. A combination of HI and SE treatment at a low concentration had no significant effect, but at a high concentration showed an additive effect, with an increase in lactate production, a decrease in succinate production and an increase in glucose uptake. Thus this work confirms that HI and SE directly influence, albeit differently, energy metabolism of the tapeworm H. diminuta .

The current study was undertaken to gain further insight into the carbohydrate metabolism of the proliferating larvae of Mesocestoides corti by studying the effect of the metabolic inhibitors oxaloacetate and iodoacetate on the incorporation of label from NaH13CO3 into the excretory products lactate and succinate. These products were converted to their methyl derivatives and analyzed by gas chromatography/mass spectrometry (GC/MS) to determine the isotope ratios. The percentage of [l-13C]lactate, [l-13C]succinate, and [1,4-13C2]succinate decreased in the presence of oxaloacetate; iodoacetate did not significantly influence the relative amount of the former, but markedly increased percentages of the latter two. The data provide information on the relative rates of the pathways and steps within them and the influence of the inhibitors on these pathways.

Ascorbate-reduced dopamine beta-hydroxylase (DBH) is inhibited by CO in a competitive manner with respect to molecular O2. Measurement of the stoichiometry of CO binding indicates 0.50 CO bound per Cu(I), which provides the first evidence that the Cu(I) centers in the reduced enzyme are structurally inequivalent. FTIR spectroscopy has been used to detect an infrared absorption band characteristic of coordinated CO, with v(CO) = 2089 cm-1. Comparison of this frequency with those of other Cu(I)-carbonyls in both inorganic and protein systems suggests a coordination site with fewer or less basic ligands than the 3-histidine site of carbon-monoxy hemocyanin.

We wanted to determine the long-term effects of a continuous infusion of PGE1 on DO2 and VO2 in patients with ARDS. Data were obtained from a randomized double-blind multicenter trial, which evaluated the effects of PGE1 on survival in patients with ARDS. Patients were stratified according to treatment and outcome: placebo-died (n = 8); PGE1-died (n = 12); placebo-survived (n = 9); and PGE1-survived (n = 8). In the placebo-died group, elevations occurred in VO2, which were associated with increases in O2ext and a constant DO2. In contrast, in the PGE1-died group, elevations in VO2 were associated with increases in DO2 and an unchanged O2ext. In the placebo-survived group, VO2 and DO2 decreased, whereas in the PGE1-survived group, VO2 and DO2 increased; however, O2ext decreased in both of these groups. Since impaired O2ext occurs in ARDS, PGE1-induced elevations in DO2, rather than compensatory increases in O2ext, may achieve better tissue oxygenation. We conclude that although the recently completed multicenter trial failed to show an enhancing effect of PGE1 on survival in patients with advanced ARDS, PGE1 may have important effects on oxygen transport and, therefore, may still have a role in the treatment of early manifestations of ARDS, either alone or in combination with other agents.

Juvenile coho were reared using photoperiod control to produce zero-age smolts. After 5 months of rearing the final densities were 6·1 (low), 12·1 (medium) and 26·2 (high) g liter −1 . Each treatment had equal dissolved oxygen. Weight, survival and seawater adaptability were not affected by density treatment. We conclude that zero-age coho salmon can be reared at densities up to at least 25 g liter −1 without impairing growth or smolt quality.