Coronary Artery Calcification as a Marker for Coronary Artery Stenosis: Comparing Kidney Failure to the General Population.

RATIONALE & OBJECTIVE: The presence of calcified plaques in the coronary arteries is associated with cardiovascular mortality and is a hallmark of chronic kidney failure, but it is unclear whether this is associated with the same degree of coronary artery stenosis as in patients without kidney disease. We compared the relationship of coronary artery calcification (CAC) and stenosis between dialysis patients and patients without chronic kidney disease (CKD). STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: 127 dialysis patients and 447 patients without CKD with cardiovascular risk factors underwent cardiac computed tomography (CT), consisting of non-contrast-enhanced CT and CT angiography. CAC score and degree of coronary artery stenosis were assessed by independent readers. PREDICTOR: Dialysis treatment. OUTCOME: Association between calcification and stenosis. ANALYTICAL APPROACH: Logistic regression to determine the association between CAC score and the presence of stenosis in a matched cohort and, in the full cohort, testing for the interaction of dialysis status with this relationship. RESULTS: 112 patients were matched from each cohort, totaling 224 patients, using propensity scores for dialysis, balancing numerous cardiovascular risk factors. Median CAC score was 210 (IQR, 19-859) in dialysis patients and 58 (IQR, 0-254) in patients without CKD; 35% of dialysis patients and 36% of patients without CKD had coronary artery stenosis ≥ 50%. Per each 100-unit higher CAC score, the matched dialysis cohort had significantly lower ORs for stenosis than the non-CKD cohort, 0.67 (95% CI, 0.52-0.83) for stenosis ≥ 50% and 0.75 (95% CI, 0.62-0.90) for stenosis ≥ 70%. LIMITATIONS: No comparison with the gold standard fractional flow reserve. CONCLUSIONS: Dialysis patients have higher risk for coronary artery stenosis with higher CAC scores, but this risk is comparatively lower than in patients without CKD with similar CAC scores. In dialysis patients, a high CAC score can easily be found without significant stenosis. Our data enable "translation" of degree of calcification to the probability of coronary stenosis in dialysis patients.

Xerocomellus (Boletaceae) in western North America.

Understanding diversity in the genus Xerocomellus in western North America has been obscured by morphological variability, widespread use of species epithets typified by specimens from Europe and eastern North America, misunderstood phylogenetic relationships, and species complexes. We collected extensively and used genetic and morphological data to establish the occurrence of ten Xerocomellus species in western North America. We generated ITS sequences from five type collections and from vouchered representative collections to clarify our understanding of existing species concepts. We describe three new species (Xerocomellus atropurpureus, X. diffractus, and X. salicicola) and propose two new combinations (X. amylosporus and X. mendocinensis), transfer Boletus coccyginus to Hortiboletus, and provide a dichotomous key to species of Xerocomellus in western North America.

Facile synthesis of supported Ru-Triphos catalysts for continuous flow application in selective nitrile reduction.

The selective catalytic hydrogenation of nitriles represents an important but challenging transformation for many homogeneous and heterogeneous catalysts. Herein, we report the efficient and modular solid-phase synthesis of immobilized Triphos-type ligands in very high yields, involving only minimal work-up procedures. The corresponding supported ruthenium-Triphos catalysts are tested in the hydrogenation of various nitriles. Under mild conditions and without the requirement of additives, the tunable supported catalyst library provides selective access to both primary amines and secondary imines. Moreover, the first application of a Triphos-type catalyst in a continuous flow process is presented demonstrating high catalyst life-time over at least 195 hours without significant activity loss.

The effect of switching protease inhibitors to raltegravir on endothelial function, in HIV-infected patients.

Objective Lipid management is one of the cornerstones of cardiovascular risk reduction. Treatment of HIV infection with protease inhibitors (PIs) may cause dyslipidaemia, whilst the integrase inhibitor raltegravir (RAL) has a relatively favorable effect on plasma lipids. We examined the effect of switching from PIs to RAL on endothelial function, and its effect on immunological and inflammatory parameters. Methods We performed a 16-week open-label prospective crossover study: 8 weeks intervention (switch PIs to RAL) and 8 weeks control (unchanged cART regimen). Flow-mediated dilatation (FMD), inflammatory plasma, and cellular markers of immune activation were measured at weeks 0, 8, and 16. Results Study participants (n = 22) with a median age of 50 years (IQR 42-60) and known HIV infection of 6.5 years (IQR 5.0-17.3) were on stable cART with undetectable HIV viral loads. After 8 weeks of RAL therapy, a reduction in FMD of -0.81% was seen, compared to +0.54% control (pairwise, p = 0.051), while fasting total cholesterol (-17% versus +10%; p < 0.001), LDL cholesterol (-21% versus -3%; p = 0.026), and triglycerides (-41% versus +18%; p = 0.001) significantly decreased during RAL therapy compared to the control. Furthermore, a relation between the change in percentage of B-1 cells and the change in FMD was found (ß 0.40, 95%CI 0.16; 0.64, p = 0.005) during treatment with RAL. Finally, during RAL therapy, 27% of the patients experienced an increased ALT rise. Conclusions We present an overall negative study, where switching from PIs to RAL slightly reduced the endothelial function while decreasing plasma lipids, thus possibly decreasing the CVD risk in the long term. A transient elevation of ALT was seen upon switch to RAL.

Balsamia (Sequestrate Helvellaceae, Ascomycota) in western North America.

Balsamia, a hypogeous, sequestrate genus in the Helvellaceae, has been characterized variously as having three to eight species in North America, and these have been considered either different from or conspecific with European species. No available modern systematic treatment of Balsamia exists to allow for accurate identification at the species level. We sequenced DNA from recent western North American Balsamia collections, assessed relationships by sequence similarity, and identified molecular taxonomic units. From these data, we determined which matched descriptions and types of named species. ITS sequences supported 12 Balsamia species in western North America, five originally described by Harkness and Fischer and seven new species that we describe here. No sequences from Balsamia collections in western North America were nested among those of European species. We found no clear evidence for separation of Balsamia into multiple genera.

Phosphinines versus mesoionic carbenes: a comparison of structurally related ligands in Au(i)-catalysis.

Gold(i) complexes based on a 2,4,6-triarylphosphinine and a mesoionic carbene derivative have been prepared and characterized crystallographically. Although structurally related, both heterocycles differ significantly in their donor/acceptor properties. These opposed electronic characteristics have been exploited in Au(i)-catalyzed cycloisomerization reactions. For the conversion of the standard substrate dimethyl 2-(3-methylbut-2-enyl)-2-(prop-2-ynyl)malonate the results obtained for both Au-catalysts were found to be very similar and comparable to the ones reported in the literature for other carbene- or phosphorus(iii)-based Au(i)-complexes. In contrast, a clear difference between the catalytic systems was found for the cycloisomerization of the more challenging substrate N-2-propyn-1-ylbenzamide. A combination of the phosphinine-based complex and [AgSbF6] or [Cu(OTf)2] leads to a catalytic species, which is more active than the mesoionic carbene-based coordination compound. We attribute these differences to the stronger π-accepting ability of phosphinines in comparison to mesoionic carbenes. The here presented results show for the first time that phosphinines can be used efficiently as π-accepting ligands in Au(i)-catalyzed cycloisomerization reactions.

Maraviroc Intensification Improves Endothelial Function in Abacavir-Treated Patients, an Open-Label Randomized Cross-Over Pilot Study.

BACKGROUND: The increased risk of abacavir in cardiovascular disease (CVD) in HIV-infected patients is still being debated. Maraviroc, a CCR5 blocker, has been shown to decrease immune activation and monocyte infiltration in atherosclerotic plaques in murine experiments. Therefore, we examined the effect of maraviroc intensification on flow-mediated dilatation (FMD) in abacavir-treated HIV-infected patients and its effect on immunological and inflammatory parameters. METHODS: A open-label prospective crossover study with a duration of 16 weeks: 8 weeks of intervention (maraviroc intensification) and 8 weeks of control (unchanged cART regimen). FMD, HIV-specific variables, expression of HIV co-receptors, markers of inflammation and coagulation and cellular markers of immune activation were measured at weeks 0, 8 and 16. The changes (Δ) in these variables were compared between intervention and control periods using non-parametric tests. To evaluate the relation with the change in FMD, linear regression modeling was used. RESULTS: Twenty-one male patients with suppressed plasma HIV-RNA, on cART, had a known HIV infection for 9.2 years (IQR 6.9-13.5) with abacavir use for 6.5 years (2.8-9.3). A significantly increased FMD of 0.73% (IQR -0.25 to 1.70) was seen after maraviroc intensification compared to a decrease of -0.42% (IQR -1.89 to 0.25; p = 0.049) in the control period. There was a negative relation between ΔFMD with ΔD-dimer (ß -22.70, 95% CI -39.27; -6.13, p = 0.011) and ΔCD95+ CD4+ T cells (ß -0.16, 95% CI -0.28; -0.04, p = 0.013), adjusted for age and duration of HIV. CONCLUSION: Maraviroc intensification modestly improves endothelial function in HIV-infected patients on an abacavir-containing regimen. TRIAL REGISTRATION: NCT01389063.

Modular solid-phase synthesis, catalytic application and efficient recycling of supported phosphine-phosphite ligand libraries.

In spite of decades of research in the field of homogeneous asymmetric catalysis the discovery of new high performance catalysts still relies heavily on trial-and-error. There is still a lack of efficient combinatorial methods which enable the synthesis and screening of vast ligand libraries, especially for bidentate phosphorus ligands. Here we present a highly modular solid-phase synthetic approach which provides facile access to libraries of phosphine-phosphite ligands in quantitative yield requiring only minimal work-up. The obtained library of supported phosphine-phosphites was successfully applied in rhodium catalyzed asymmetric hydrogenation obtaining high enantioselectivities up to 98%. Also, these polymer supported ligands could be successfully recycled under batch conditions exhibiting only a small decline of activity and no loss of selectivity.

Cyclometalation of aryl-substituted phosphinines through C-H-bond activation: a mechanistic investigation.

A series of 2,4,6-triarylphosphinines were prepared and investigated in the base-assisted cyclometalation reaction using [Cp*IrCl2]2 (Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl) as the metal precursor. Insight in the mechanism of the C-H bond activation of phosphinines as well as in the regioselectivity of the reaction was obtained by time-dependent (31)P{(1)H} NMR spectroscopy. At room temperature, 2,4,6-triarylphosphinines instantaneously open the Ir-dimer and coordinate in an η(1)-fashion to the metal center. Upon heating, a dissociation step towards free ligand and an Ir-acetate species is observed and proven to be a first-order reaction with an activation energy of ΔEA = 56.6 kJ mol(-1) found for 2,4,6-triphenylphosphinine. Electron-donating substituents on the ortho-phenyl groups of the phosphorus heterocycle facilitate the subsequent cyclometalation reaction, indicating an electrophilic C-H activation mechanism. The cyclometalation reaction turned out to be very sensitive to steric effects as even small substituents can have a large effect on the regioselectivity of the reaction. The cyclometalated products were characterized by means of NMR spectroscopy and in several cases by single-crystal X-ray diffraction. Based on the observed trends during the mechanistic investigation, a concerted base-assisted metalation-deprotonation (CMD) mechanism, which is electrophilic in nature, is proposed.

Relapse prevention with gepirone ER in outpatients with major depression.

To evaluate long-term efficacy and tolerability of the serotonin 5-HT1A receptor agonist, gepirone extended release (ER), a multicenter, randomized, placebo-controlled relapse prevention study was performed in patients with recurrent major depression (DSM-IV criteria). Patients 18 to 70 years, with a primary diagnosis of recurrent major depression (DSM-IV; 296.3) and a screening and baseline HAMD-17 total score >/=20 were eligible. After a 3- to 14-day (dependent on pretrial medication) single-blind placebo washout period, eligible patients entered an 8- or 12-week (depending on time to remission) open-label gepirone ER treatment period. They initially received a dose of 20 mg/d gepirone ER and were titrated to a dose of 40 to 80 mg/d. Patients who achieved remission (HAMD-17 total score /=16 or discontinuation for lack of efficacy. A total of 420 patients were treated in the open-label phase. Of these, 303 (72.1%) completed the open-label phase and 250 (59.5%) fulfilled the criteria for remission and were randomized into the double-blind continuation phase (gepirone ER: n = 126; placebo: n = 124). The mean (+/-SD) final titrated dose of gepirone ER was 61.9 (+/-17.0) mg/d in the double-blind continuation phase. The relapse rate in the gepirone ER group was statistically significantly lower than that in the placebo group, 23.0% versus 34.7%, respectively (P = 0.024). During the open-label phase, adverse events that occurred in more than 5% of patients were nausea (15.7%), dizziness (13.1%), headache (12.9%), insomnia (6.2%), and vertigo (6.0%). During the continuation phase, the incidence of newly or re-emerging adverse events was similar with gepirone ER (43.7%) and placebo (42.7%). Adverse events different from those occurring during the open-label phase were not apparent. All adverse events occurred in less than 5% of patients with the exception of flu syndrome and headache. In conclusion, gepirone ER at a dose range of 40 to 80 mg/d is effective for relapse prevention in patients with recurrent major depression. It is well tolerated during long-term treatment for up to approximately one year.

A double-blind, randomized, group-comparative study of the tolerability and efficacy of 6 weeks' treatment with mirtazapine or fluoxetine in depressed Chinese patients.

AIM: To compare the efficacy and tolerability of mirtazapine and fluoxetine treatment in a sample population consisting of Chinese patients suffering moderate-to-severe depression. METHOD: 133 patients with a diagnosis of major depressive episode (DSM-IV) and scoring 15 or more on the 17-item Hamilton Rating Scale for Depression (HAM-D) were randomly assigned to receive 6 weeks of treatment with either mirtazapine (15-45 mg/day) or fluoxetine (20-40 mg/day). Efficacy was assessed using the HAM-D and Clinical Global Impressions scale, with analyses performed on the intent-to-treat sample using the last-observation-carried-forward method. Safety analysis was based on the all-subjects-treated group. RESULTS: Mean daily doses were 34.1 mg for mirtazapine (N = 66) and 30.7 mg for fluoxetine (N = 66). Thirty patients in the mirtazapine group and 22 in the fluoxetine group dropped out. Both drugs proved equally effective for reduction of the overall symptoms of depression throughout the treatment period. At day 42, the mean reductions in HAM-D total score (compared with baseline) were 11.8 and 10.6 for the mirtazapine and fluoxetine groups, respectively; however, the changes were not statistically significant. Both treatments were well tolerated, with more nausea and influenza-like symptoms observed for the fluoxetine group, and greater weight increase and somnolence for the mirtazapine analog. CONCLUSION: Both mirtazapine and fluoxetine were indistinguishable in effectiveness for treatment of depressive symptoms, and both were well tolerated by our population of depressed Chinese patients. In line with analogous Western reports, the safety of mirtazapine and fluoxetine was comparable for our depressed Chinese patients; however, slightly different side effect profiles were noted for the 2 drugs in our study.

Levels of monocyte reactive oxygen species are associated with reduced natural killer cell activity in major depressive disorder.

Major depressive disorder (MDD) is associated with reductions in natural killer cell activity (NKCA), however the mechanism(s) mediating reduced NKCA in MDD has yet to be determined. In light of evidence that MDD is associated with an inflammatory immune response, we propose that reactive oxygen species (ROS), generated by inflammatory leukocytes (monocytes and/or neutrophils), may mediate the suppression of NKCA in MDD. Intracellular levels of monocyte ROS were significantly associated with reductions in NKCA in outpatients (n = 15) diagnosed with MDD. Sleep disturbance was also significantly correlated with reductions in NKCA. Elevated levels of ROS may be an additional characteristic of a subset of depressed patients in whom an inflammatory response persists and elevations in ROS may, in part, mediate the associations observed between MDD, cardiovascular disease, and cancer.

Ionic implantation of silicone chronic venous access devices does not alter thrombotic complications: a double-blinded, randomized clinical trial.

BACKGROUND: Ion implantation of silicone vascular catheters has been shown in preclinical and pilot studies to alter the thrombogenicity of silicone surfaces through the reduced adherence of thrombin. This prospective, randomized double-blinded study was designed to detect differences in function related to thrombotic events between ion-implanted and standard silicone chronic venous access devices (CVAD) placed in patients with cancer who are receiving chemotherapy. METHODS: Patients with nonleukemic malignancies who required venous access for chemotherapy and who were not receiving anticoagulants were randomized to receive standard or ion-implanted CVAD. Postoperative functional assessments of the ease of infusion or aspiration were performed by oncology nurses caring for the patients. RESULTS: Follow-up, available for 100 of 106 randomized patients, showed more episodes of occlusion to aspiration in the ion implantation group (47%) than in the control group (39%) but this difference was not significant. There were no significant differences between the 2 groups in the number of occasions when anticoagulation or local thrombolytic therapy was required nor were there differences in the numbers of infection or deep venous thromboses. CONCLUSIONS: Ion implantation of silicone catheter material does not alter the incidence of local thrombotic complications of CVAD. Although there were no serious complications resulting from this treatment, the use of ion-implanted catheters cannot be recommended on the basis of this trial.

Monocyte 5-HT1A receptors mediate pindobind suppression of natural killer cell activity: modulation by catalase.

Serotonin (5-hydroxytryptamine; 5-HT) modulates constituents of the immune system. 5-HT1A receptor antagonists potently suppress lymphocyte function. NK cell activity (NKCA) was measured after exposure of mononuclear cells to the 5-HT1A receptor antagonist pindobind and the 5-HT(1C/2) receptor antagonist ketanserin. Elutriated monocytes were exposed to pindobind, incubated with peripheral blood lymphocytes (PBL) in the presence or absence of an H2O2 scavenger catalase, and NKCA measured. Pindobind, but not ketanserin, suppressed NKCA in vitro. Pindobind-treated monocytes suppressed NKCA, whereas pindobind treatment of PBL did not affect NKCA. Catalase inhibited pindobind-induced suppression of NKCA. These data are consistent with previous results that 5-HT modulates NKCA via 5-HT1A receptors on monocytes and suggest that 5-HT may abrogate monocyte suppression of NKCA by inhibiting monocyte signals such as H2O2.

Routine chest roentgenography is unnecessary in the work-up of stage I and II breast cancer.

PURPOSE: Clinical practice guidelines of many professional societies call for routine staging chest x-rays (SCXR) for all patients with invasive cancer. Given the estimated 157,000 patients annually for whom this recommendation pertains, this screening examination represents a considerable health care expenditure. If it were shown that SCXR rarely changed the management of low-risk subsets of this population, it might be possible to selectively omit this practice from the care of these patients with substantial resultant cost savings. PATIENTS AND METHODS: All patients with clinical stage I and II breast cancer presenting to the Baystate Medical Center from 1989 through 1997 were identified through the Tumor Registry. Their hospital records were reviewed for clinical presentation and documentation of SCXR. RESULTS: One thousand four hundred ninety-four patients were identified with clinical stage I and II disease. SCXR were available for review on 1,003 patients. Only one asymptomatic patient was upstaged to stage IV based on a SCXR. Two patients with primary lung tumors were also identified. These data demonstrate an asymptomatic pulmonary metastasis detection rate of 0. 099% (95% confidence interval, 0.0% to 0.6%). The total charges of SCXR for this group approached $180,000. CONCLUSION: These data demonstrate the low diagnostic yield and high cost of routine SCXR in the management of asymptomatic patients with clinical stage I and stage II breast cancer. Because other studies have shown that SCXR changes neither quality of life nor overall survival, SCXR should be limited to symptomatic patients in whom metastatic disease is suspected.

Multiple ejaculations and chronic fluoxetine: effects on male rat copulatory behavior.

Male rats were treated with fluoxetine (FLX) or vehicle daily for 14 days and copulatory behavior tested on day 15. Rats were either mated to three ejaculations or to sexual exhaustion. Both standard measures and the mount bout analysis were used to evaluate the effects of the chronic FLX on male rat copulatory behavior. Only 56.25% of the animals treated with FLX achieved three ejaculations. FLX inhibited the consumatory aspect of male sexual behavior, especially the ability to achieve three ejaculations, but there was no effect on the propensity of the male to pursue the female. These differences were observed for the first three ejaculations. Analysis of the last three ejaculations in those animals that mated to exhaustion did not reveal an effect of FLX. The behavioral pattern of FLX-treated animals during the first three ejaculations resembled that observed during the last three ejaculatory series in the vehicle-treated animals that mated to exhaustion. The results are discussed in terms of the serotonergic effects on male rat sexual behavior.

The effects of St. John's Wort (Hypericum perforatum) on NK cell activity in vitro.

St. John's Wort (Hypericum perforatum; H. perforatum) is a popular herbal supplement used to treat mild to moderate depression. H. perforatum possesses serotonergic properties such as inhibition of serotonin (5-hydroxytryptamine; 5-HT) reuptake. Serotonergic pharmacotherapy is associated with amelioration of depression as well as increases in natural killer (NK) cell activity (NKCA). Also, 5-HT and 5-HT analogs augment NKCA in vitro. Considering the serotonergic properties of H. perforatum, the effects of H. perforatum on NKCA were assessed in vitro. Mononuclear cells (MNCs) from normal donors were exposed in vitro to an extract of H. perforatum (LI160s) or established 5-HT stimulators of NKCA. After an overnight incubation, cells were washed and a standard 51Cr-release cytotoxicity assay performed to assess NKCA. LI160s at all concentrations failed to augment NKCA. However, in corroboration of previous studies, 5-HT, the selective serotonin reuptake inhibitors (SSRIs), paroxetine and norfluoxetine, and alpha-interferon augmented NKCA above control levels. Though an efficacious treatment for mild to moderate depression, H. perforatum differs from commonly prescribed serotonergic antidepressants insofar as H. perforatum fails to enhance NKCA in vitro. Therefore, the present results are consistent with pharmacologic studies indicating that H. perforatum possesses, at best, weak serotonergic activity.

The unsatisfactory margin in breast cancer surgery.

BACKGROUND: Surgical margin involvement with breast cancer usually results in obligatory reexcision or mastectomy. While unalterable occult host and pathologic factors may interfere with margin clearance during the initial excision, it is possible that alterations in surgical technique might increase the likelihood of obtaining satisfactory margins. METHODS: Two hundred and thirty-five patients who were candidates for breast conservation therapy were identified for 1991 and 1996 using the Tumor Registry. Margins were defined as "unsatisfactory" if there was microscopic involvement with tumor or the margin was close at initial excisional biopsy and the surgeon opted for reexcision. Multiple logistic regression analyses of factors associated with margin status were performed. RESULTS: One hundred thirty-two (56%) patients had positive or close (unsatisfactory) margins; this rate increased from 51% in 1991 to 59% in 1996. Patients with unsatisfactory margins underwent more procedures (mean 2.0 versus 1.2; P <0.0001) than patients whose margins were satisfactory. The breast conservation rate for patients with unsatisfactory margins was 64% compared with 99% for patients with satisfactory margins. A multiple logistic regression demonstrated that patients with unsatisfactory margins were 67 times more likely to have a mastectomy than patients whose margins were satisfactory after adjusting for other significant factors (P <0.0001). The practice of fine needle aspiration biopsy, orientation of specimen margins by the surgeon, and reexcision of tumor at the first operation were statistically significant technical factors in obtaining satisfactory margins. Significant pathology factors were extensive intraductal component (EIC), lobular or ductal extension, and tumor size. CONCLUSION: These data show that technical factors in the surgical management of breast cancer, as well as biological factors such as EIC, can influence the success of breast conservation.

Intrapancreatic ciliated enteric duplication cyst presenting with biliary obstruction.

A 46-yr-old man presenting with biliary obstruction from an intrapancreatic tumor underwent pancreaticoduodenectomy. The pathology report showed the tumor to be an enteric duplication cyst. Diagnostic imaging features and operative management are discussed.