Survey of fungi and yeast in polymicrobial infections in chronic wounds

OBJECTIVE

To assess the incidence, abundance and species diversity of fungi in chronic wounds, as well as to describe the associations of major fungi populations.

METHOD

Comprehensive molecular diagnostic reports were evaluated from a total of 915 chronic wounds in a retrospective study.

RESULTS

Of the 915 clinical specimens, 208 (23%) were positive for fungal species. These samples were further compared in a compiled dataset, and sub-classified among the four major chronic wound types (decubitus ulcer, diabetic foot ulcer, non-healing surgical wound, and venous leg ulcer). The most abundant fungi were yeasts in the genus Candida; however, Curvularia, Malessezia, Aureobasidium, Cladosporium, Ulocladium, Engodontium and Trichtophyton were also found to be prevalent components of these polymicrobial infections. A notable bacterial/fungal negative correlation was found to be apparent between Staphylococcus and Candida. There were also significant relationships between both bacterial and fungal genera and patient metadata including gender, diabetes status and cardiovascular comorbidities.

CONCLUSION

This microbial survey shows that fungi are more important wound pathogens and opportunistic pathogens than previously reported, exemplifying the impact of these under-reported pathogens. With the application of modern cost-effective and comprehensive molecular diagnostics, clinicians can now identify and address this significant component of chronic wound bioburden with targeted therapies, thereby improving healing trajectories.

AMG 386 in combination with sorafenib in patients (pts) with metastatic renal cell cancer (mRCC): A randomized, double-blind, placebo-controlled, phase II study

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Background: AMG 386 inhibits angiogenesis by sequestering angiopoietin-1 and -2, thus preventing their interaction with the Tie2 receptor on endothelial cells. Combination with VEGF receptor inhibition has demonstrated additive effects in vivo. The efficacy and tolerability of sorafenib plus AMG 386, an investigational peptide-Fc fusion protein, were evaluated in mRCC pts.

Methods: Treatment-naive pts with clear cell mRCC were randomized 1:1:1 to sorafenib 400 mgPO BID plus AMG 386 10 mg/kg (Arm A) or 3 mg/kg (Arm B) QW; or placebo (Arm C) IV QW. Endpoints were progression-free survival (PFS; primary); and (secondary) objective response rate (ORR), change in tumor burden, adverse events (AEs) and pharmacokinetics. Tumor assessment was performed at baseline and every 8 weeks thereafter.

Results: 152 pts were randomized: Arms A/B/C, n=50/51/51. 60/61/61% of pts had intermediate and 40/39/37% had low MSKCC risk at baseline. PFS was similar in all 3 arms, whereas ORR was higher in the AMG 386 arms ( Table ). In Arms A/B/C the incidence of grade ≥ 3 AEs was 66/73/86% and serious AEs 36/49/28%. The most common AEs included diarrhea (70/67/56%; grade ≥3 8/10/8%), hand- foot syndrome (52/47/54%; grade ≥3 12/16/28%), alopecia (50/45/50%; grade ≥3 0/0/2%), and hypertension (42/49/46%; grade ≥3 18/20/14%). Median steady-state Cmax and Cmin for AMG 386 were similar to those reported previously. Sorafenib coadministration did not markedly affect AMG 386 exposure.

Conclusions: Sorafenib plus AMG 386 was tolerable but did not improve PFS compared with sorafenib plus placebo. Increased ORR and the observed reduction in tumor burden are suggestive of an antitumor effect of AMG 386 in mRCC.

[Table: see text]

[Table: see text]

Pharmacokinetics of dexmedetomidine in Chinese post-surgical intensive care unit patients

BACKGROUND

Dexmedetomidine is a rather new drug in China. We sought to describe the pharmacokinetics of dexmedetomidine in patients requiring post-operative sedation and ventilation in our surgical intensive care unit.

METHODS

Twenty-two patients received post-operative infusions of dexmedetomidine at 6 μg/kg/h for 10 min, followed by 0.4 μg/kg/h for 350 min. Venous blood samples were drawn and assayed for plasma concentration. The pharmacokinetics were analysed using a nonlinear mixed-effect model with an interindividual and intraindividual error model. An initial estimation was performed to determine which of the one-, two- or three-compartment models is best to describe the concentration-time data. The covariates age, gender, weight, height, lean body mass (LBM), body surface area (BSA) and body mass index (BMI) were tested for significant effects on parameters using a stepwise forward addition and backward elimination approach. Covariate effects were judged based on changes in the objective function value (OFV).

RESULTS

The pharmacokinetics of dexmedetomidine were best described by a three-compartment model. The model was further improved when height was a covariate of systemic clearance (Cl1), with a decrease in OFV by -13.56 (P<0.01). From the heights of 155-178 cm, Cl1 increased by approximately 143%. The final pharmacokinetic parameter values were as follows: V1 =63.4 l, V2=41.3 l, V3 =284.3 l, Cl1=0.47×(height/160 cm)(6.42) l/min, Cl2=2.43 l/min and Cl3=0.086 l/min.

CONCLUSIONS

This study identified (i) the effect of height on the pharmacokinetics of dexmedetomidine; (ii) that there is no influence of age, gender, weight, LBM, BSA and BMI on pharmacokinetic parameters; and (iii) it established a preliminary population pharmacokinetic model for Chinese patients.

Measurement of the parity-violating longitudinal single-spin asymmetry for W± boson production in polarized proton-proton collisions at sqrt[s] = 500 GeV

We report the first measurement of the parity-violating single-spin asymmetries for midrapidity decay positrons and electrons from W+ and W- boson production in longitudinally polarized proton-proton collisions at sqrt[s] = 500 GeV by the STAR experiment at RHIC. The measured asymmetries, A(L)(W+) = -0.27 ± 0.10(stat.) ± 0.02(syst.) ± 0.03(norm.) and A(L)(W-) = 0.14 ± 0.19(stat.) ± 0.02(syst.) ± 0.01(norm.), are consistent with theory predictions, which are large and of opposite sign. These predictions are based on polarized quark and antiquark distribution functions constrained by polarized deep-inelastic scattering measurements.

DMP1 processing is essential to dentin and jaw formation

Dentin matrix protein 1 (DMP1), an acidic protein that is essential to the mineralization of bone and dentin, exists as proteolytically processed fragments in the mineralized tissues. In this study, we characterized the tooth and jaw phenotypes in transgenic mice containing no wild-type DMP1, but expressing a mutant DMP1 in which Asp(213), a residue at one cleavage site, was replaced by Ala(213) (named "Dmp1-KO/D213A-Tg" mice). The teeth and mandible of Dmp1-KO/D213A-Tg mice were compared with those of wild-type, Dmp1-knockout (Dmp1-KO), and Dmp1-KO mice expressing the normal Dmp1 transgene. The results showed that D213A-DMP1 was not cleaved in dentin, and the expression of D213A-DMP1 failed to rescue the defects in the dentin, cementum, and alveolar bones in the Dmp1-KO mice. These findings indicate that the proteolytic processing of DMP1 is essential to the formation and mineralization of dentin, cementum, and jaw bones.

Randomized, double-blind, placebo-controlled phase II study of AMG 386 in combination with cisplatin and capecitabine (CX) in patients (pts) with metastatic gastroesophageal adenocarcinoma

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Background: AMG 386, a first-in-class investigational peptide-Fc fusion protein (peptibody), blocks angiogenesis via inhibiting the interaction between angiopoietins-1 and -2 and the Tie2 receptor. We evaluated the efficacy and tolerability of AMG 386 or placebo plus CX in the first-line treatment of metastatic gastroesophageal adenocarcinoma.

Methods: Pts with confirmed metastatic adenocarcinoma of the stomach, gastroesophageal junction or distal esophagus were randomized 1:1:1 to receive CX (cisplatin, 80 mg/m2 IV Q3W; capecitabine, 1,000 mg/m2 orally BID for 14 days Q3W) plus AMG 386 10 mg/kg (Arm A), 3 mg/kg (Arm B), or placebo (Arm C) IV QW. The primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate (ORR; in pts with measurable disease), adverse events (AEs), and pharmacokinetics (PK).

Results: 171 pts were randomized (Arm A/B/C, n = 56/59/56). Efficacy results are summarized in the table. The incidence of grade ≥ 3 AEs in Arms A/B/C was 80/84/75%. Serious AEs occurred in 73/60/47% and serious AEs grade ≥ 3 in 66/60/43% of pts. AEs in Arms A/B/C included abdominal pain (30/40/17%; grade ≥ 3, 18/3/4%), peripheral edema (13/29/6%; grade ≥ 3, 0/2/0%), venous thromboembolic events (20/22/19%; grade ≥ 3, 20/19/17%), and pulmonary embolism (9/3/15%; grade ≥ 3, 9/2/13%). Median AMG 386 Cmax and Cmin values at steady state after CX coadministration were dose-proportional. Coadministration with CX did not markedly affect AMG 386 exposure.

Conclusions: In this study, AMG 386 plus CX did not significantly improve PFS or ORR over placebo plus CX in this patient population. The toxicity of the combination of AMG 386 plus CX, compared with placebo, was greater but manageable. No unexpected AEs occurred.

[Table: see text]

[Table: see text]

Adjuvant chemotherapy for gastric cancer: Less drug, same efficacy

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Background: Adjuvant chemotherapy is proved to improve survival in gastric cancer by meta-analyses. However, no evidence showed the best regimen. We conducted a retrospective analysis to compare triplets with doublets in the adjuvant setting.

Methods: We collected data from January 2004 to December 2008 from patients performed radical surgery and adjuvant chemotherapy. Doublets were defined as 5-FU 750 mg/m2 (d1- 5) or capecitabine 1,000 mg/m2 (d1-14) plus cisplatin 60 mg/m2 (d1) or oxaliplatin 130 mg/m2 (d1), while triplets had epirubicin 50 mg/m2 (d1) added. Chemotherapy was initiated within 6 weeks after surgery, repeated every three weeks and planned for 6 cycles. Patients were followed up in the outpatient clinic until death or April 30, 2010. Cox proportional-hazard model and chi-square test were used to test statistical difference.

Results: A total of 316 patients (210 in doublets, 106 in triplets) had a median follow-up time of 47 months. 77 patients died at the end of follow-up (3-year survival of 67.4%).Two groups were well balanced except age (median age of 57 in doublets, 51 in triplets, p < 0.001). All the patients tolerated well, with few grade 3/4 side effects (21.9% in doublets, 30.2% in triplets, p = 0.107). Two groups had similar disease-free survival (median DFS, 16 months vs. 23 months, p = 0.656) and overall survival (3-year survival rate, 59.6% vs. 64.8%, p = 0.293). Subgroup analysis showed the same benefit on survival between the two groups.

Conclusions: Our study suggested doublets and triplets had the same efficacy as the adjuvant chemotherapy. Furthermore, doublets seem more cost-effective.

[Table: see text]

No significant financial relationships to disclose.

Application of a modified linear solvation energy relationship (LSER) model to retention on a butylimidazolium-based column for high performance liquid chromatography

Previously, a new HPLC stationary phase based on n-butylimidazolium bromide was investigated using a linear solvation energy relationship (LSER) to systematically evaluate the intermolecular interactions between 32 test solutes and the stationary phase. The results and further comparisons with conventional reversed phase systems revealed that retention properties are similar to phenyl phases in both methanol/water and acetonitrile/water mixtures. In this work, the LSER model is extended by including the degree of ionization molecular descriptor, D, which takes into account the pK(a) of ionizable analytes and the pH of the mobile phase. The D molecular descriptor has been further divided into D(+) and D(-) components that separately account for the ionization of basic and acidic solutes, respectively. This is the first study where the ionization terms for weakly acidic solutes and weakly basic solutes have been separated. LSER results obtained with the expanded solute set with and without the inclusion of the D(+) and D(-) solute descriptors were compared. The improved correlation and standard error obtained for the expanded test set in the presence and absence of the D(+) and D(-) descriptors (R(2): 0.987 vs 0.846; SE: 0.051 vs 0.163 for 60% MeOH) support inclusion of these additional terms. Further, the coefficients obtained from the multiple linear regression for the expanded test set with the D(+) and D(-) descriptors were more consistent with the coefficients obtained when the test set included just neutral analytes. In addition, the expanded LSER model did a better job of predicting elution order for the ionizable analytes. This work provides further supporting evidence for the multimodal nature of the butylimidazolium stationary phase.

Ribosomal protein S27-like and S27 interplay with p53-MDM2 axis as a target, a substrate and a regulator

Several ribosomal proteins regulate p53 function via modulating MDM2. We recently found that RPS27L, a RPS27 like protein, is a direct p53 inducible target. Here we showed that RPS27 itself is a p53 repressible target. Furthermore, the N-terminal region of either RPS27L or RPS27 binds to MDM2 on the central acidic domain of MDM2. RPS27L or RPS27 forms an in vivo triplex with MDM2-p53 and competes with p53 for MDM2 binding. Like p53, RPS27L, but not RPS27, is a short-lived protein and a novel MDM2 substrate. Degradation of RPS27L requires the RING or acidic domain of MDM2. Ectopic expression of RPS27L or RPS27 inhibits MDM-2-mediated p53 ubiquitination and increases p53 levels by extending p53 protein half-life, whereas siRNA silencing of RPS27L decreases p53 levels by shortening p53 half-life with a corresponding reduction in p53 transcription activity. RPS27L is mainly localized in the cytoplasm, but upon p53-activating signals, a portion of RPS27L shuttled to the nucleoplasm where it co-localizes with MDM2. Both cytoplasmic and nuclear p53, induced by ribosomal stress, were reduced upon RPS27L silencing. Our study reveals a multi-level interplay among RPS27L/S27 and p53-MDM2 axis with RPS27L acting as a p53 target, an MDM2 substrate, and a p53 regulator.

Rechargeable infection-responsive antifungal denture materials

Candida-associated denture stomatitis (CADS) is a significant clinical concern. We developed rechargeable infection-responsive antifungal denture materials for potentially managing the disease. Polymethacrylic acid (PMAA) was covalently bound onto diurethane dimethacrylate denture resins in the curing step. The PMAA resins bound cationic antifungal drugs such as miconazole and chlorhexidine digluconate (CG) through ionic interactions. The anticandidal activities of the drug-containing PMAA-resin discs were sustained for a prolonged period of time (weeks and months). Drug release was much faster at acidic conditions (pH 5) than at pH 7. Drugs bound to the denture materials could be "washed out" by treatment with EDTA, and the drug-depleted resins could be recharged with the same or a different class of anticandidal drugs. These results suggest clinical potential of the newly developed antifungal denture materials in the management of CADS and other infectious conditions.

Bandwidth tuning triggers interplay of charge order and superconductivity in two-dimensional organic materials

We observe charge-order fluctuations in the quasi-two-dimensional organic superconductor β''-(BEDT-TTF)2SF5CH2CF2SO3, both by means of vibrational spectroscopy, locally probing the fluctuating charge order, and by investigating the in-plane dynamical response by infrared reflectance spectroscopy. The decrease of the effective electronic interaction in an isostructural metal suppresses both charge-order fluctuations and superconductivity, pointing to their interplay. We compare the results of our experiments with calculations on the extended Hubbard model.

Measurement of the bottom quark contribution to nonphotonic electron production in p + p collisions at √s=200 GeV

The contribution of B meson decays to nonphotonic electrons, which are mainly produced by the semileptonic decays of heavy-flavor mesons, in p + p collisions at √s=200  GeV has been measured using azimuthal correlations between nonphotonic electrons and hadrons. The extracted B decay contribution is approximately 50% at a transverse momentum of pT≥5  GeV/c. These measurements constrain the nuclear modification factor for electrons from B and D meson decays. The result indicates that B meson production in heavy ion collisions is also suppressed at high pT.