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A series of three 2,5-Diketopiperazine (DKPs) were synthesized via one-pot process through the post- isocyanide-based multicomponent reactions (IMCR)-transformation strategy. This strategy emphasizes the role of orthogonal bifunctional reagents in the IMCR process to increase their synthetic potential, allowing us accessing a synthetic platform from which it is possible to obtain privileged heterocyclic peptidomimetics via lactamization reaction.

Tissue engineering approaches for bone repair have rapidly evolved due to the development of novel biofabrication technologies, providing an opportunity to fabricate anatomically-accurate living implants with precise placement of specific cell types. However, limited availability of biomaterial inks, that can be 3D-printed with high resolution, while providing high structural support and the potential to direct cell differentiation and maturation towards the osteogenic phenotype, remains an ongoing challenge. Aiming towards a multifunctional biomaterial ink with high physical stability and biological functionality, this work describes the development of a nanocomposite biomaterial ink (Mg-PCL) comprising of magnesium hydroxide nanoparticles (Mg) and polycaprolactone (PCL) thermoplastic for 3D printing of strong and bioactive bone regenerative scaffolds. We characterised the Mg nanoparticle system and systematically investigated the cytotoxic and osteogenic effects of Mg supplementation to human mesenchymal stromal cells (hMSCs) 2D-cultures. Next, we prepared Mg-PCL biomaterial ink using a solvent casting method, and studied the effect of Mg over mechanical properties, printability and scaffold degradation. Furthermore, we delivered MSCs within Mg-PCL scaffolds using a gelatin-methacryloyl (GelMA) matrix, and evaluated the effect of Mg over cell viability and osteogenic differentiation. Nanocomposite Mg-PCL could be printed with high fidelity at 20 wt% of Mg content, and generated a mechanical reinforcement between 30%–400% depending on the construct internal geometry. We show that Mg-PCL degrades faster than standard PCL in an accelerated-degradation assay, which has positive implications towards in vivo implant degradation and bone regeneration. Mg-PCL did not affect MSCs viability, but enhanced osteogenic differentiation and bone-specific matrix deposition, as demonstrated by higher ALP/DNA levels and Alizarin Red calcium staining. Finally, we present proof of concept of Mg-PCL being utilised in combination with a bone-specific bioink (Sr-GelMA) in a coordinated-extrusion bioprinting strategy for fabrication of hybrid constructs with high stability and synergistic biological functionality. Mg-PCL further enhanced the osteogenic differentiation of encapsulated MSCs and supported bone ECM deposition within the bioink component of the hybrid construct, evidenced by mineralised nodule formation, osteocalcin (OCN) and collagen type-I (Col I) expression within the bioink filaments. This study demonstrated that magnesium-based nanocomposite bioink material optimised for extrusion-based 3D printing of bone regenerative scaffolds provide enhanced mechanical stability and bone-related bioactivity with promising potential for skeletal tissue regeneration.

3D bioprinting of constructs for tissue engineering and regenerative medicine has steadily gained attention due to its potential to fabricate anatomically-precise living constructs, localise specific cell types and enable the regeneration of functional tissues in a clinical setting. However, the limited availability of bioinks that can be successfully 3D bioprinted with high fidelity and simultaneously provide encapsulated cells with a tailored, low-stiffness microenvironment supporting functional tissue formation remains an unmet challenge. To address both the physical and biological limitations of available bioinks, this study aimed to develop a nanocomposite bioink (Sr-GelMA) comprising of strontium-carbonate (Sr) nanoparticles and low concentration (5 w/v%) gelatin-methacryloyl (GelMA) hydrogel for extrusion-based 3D bioprinting of low-stiffness cell-laden scaffolds with high shape fidelity and bone-specific cell signalling factors. We systematically investigated the effect of Sr incorporation on hydrogel physico-chemical properties, print fidelity, scaffold shape retention, as well as cell viability, osteogenic differentiation and in vitro bone formation. Nanocomposite Sr-GelMA hydrogels retained their physical and mechanical properties, while rheological studies revealed a significant increase in viscosity profiles that led to notably enhanced printability compared to GelMA alone. Moreover, bioprinted Sr-GelMA scaffolds exhibited excellent shape fidelity evidenced by a defined pore geometry on the x-y-z axis, resulting in an interconnected bioink filament and pore network that was maintained even after long-term culture and osteogenic differentiation (28 days) of human mesenchymal stromal cells (hMSCs). The presence of clustered Sr nanoparticles in the cell-laden bioink allowed high quality bioprinting combined with high hMSC viability (>95%) post-fabrication. Furthermore, Sr addition resulted in enhanced osteogenic differentiation of hMSCs as revealed by higher alkaline phosphatase (ALP) levels, osteocalcin (OCN) and collagen type-I (Col I) expression, with mineralised nodule formation distributed homogenously throughout the bioprinted construct. This study demonstrated that strontium-based nanocomposite bioinks optimised for extrusion-based 3D bioprinting of osteoconductive scaffolds support long-term shape retention with promising potential for bone tissue regeneration.

Hormones are an important component in the regulatory networks guiding plant development. Cytokinins are involved in different physiological and developmental processes in plants. In the model plant Arabidopsis thaliana, cytokinin application during gynoecium development produces conspicuous phenotypes. On the other hand, Brassica napus, also known as canola, is a crop plant belonging to the Brassicaceae family, as A. thaliana. This makes B. napus a good candidate to study whether the cytokinin responses observed in A. thaliana are conserved in the same plant family. Here, we observed that cytokinin treatment in B. napus affects different traits of flower and fruit development. It increases ovule and seed number, affects stamen filament elongation and anther maturation, and causes a conspicuous overgrowth of tissue in petals and gynoecia. Furthermore, cytokinin recovers replum development in both wild type B. napus and in the A. thaliana rpl ntt double mutant, in which no replum is visible. These results indicate both conserved and novel responses to cytokinin in B. napus. Moreover, in this species, some cytokinin-induced phenotypes are inherited to the next, untreated generation, suggesting that cytokinins may trigger epigenetic modifications.

Background: Biodegradable polymers were developed to reduce the hypersensitivity reaction associated to durable polymers found with the first generation drug-eluting stents, while maintaining antiproliferative efficacy and increasing safety. This study evaluated the 9-month angiographic follow-up and long-term clinical outcomes of biodegradable polymer-coated drug-eluting stents compared with identical platform metallic stents in patients with high-risk for restenosis. Methods: Patients with a reference diameter ≤ 2.5 mm, lesion length ≥ 15 mm, diabetes, or a combination of these characteristics were selected from the population of the PAINT trial. These patients were previously randomized and allocated for percutaneous coronary intervention with either a sirolimus-eluting biodegradable polymer-coated stent, a paclitaxel-eluting biodegradable polymer-coated stent, or an identical metallic platform stent, at a ratio of 2:2:1. Results: One hundred and seventy-eight patients were treated with biodegradable polymer-coated drug-eluting stents (n = 142) or bare metal stents (n = 36). At the 9-month angiographic follow-up, biodegradable polymercoated drug-eluting stents had lower rates of late loss (0.40 ± 0.42 mm vs. 0.90 ± 0.47 mm; p < 0.01) and binary restenosis (7.4% vs. 25%; p

Good quality zinc oxide ZnO films were deposited on alumina substrates by the polymeric precursor method (PPM) using zinc acetate as the precursor. X-ray diffraction (XRD) was used to confirm the crystallinity of the zinc oxide films which were free of impurities and SEM study revealed the uniform deposition of fine grains with a thickness of 120 nm. ZnO films were used for CO gas detection at different times by recording the change in the film conductance. The faster response of ZnO sensors to CO gas is believed to be due to high porous sensing films which show higher surface-to-volume ratio. The O 2 ′, O″, O ′ species concentration emerging from the [ZnO 5 ·VO•]+1/2O 2 → [ZnO 6 ] chemisorptions reaction affects the ZnO gas sensor response owing to the fact that the oxygen ion acts as a trap for electrons from the bulk of films.

Bioprinting of living cells is rapidly developing as an advanced biofabrication approach to engineer tissues. Bioinks can be extruded in three-dimensions (3D) to fabricate complex and hierarchical constructs for implantation. However, lack of functionality can often be attributed to poor bioink properties. Indeed, advanced bioinks encapsulating living cells should: (i) present optimal rheological properties and retain 3D structure post-fabrication, (ii) promote cell viability and support cell differentiation, (iii) localise proteins of interest (e.g. vascular endothelial growth factor (VEGF)) to stimulate encapsulated cell activity and tissue ingrowth upon implantation. In this study, we present the results of the inclusion of a synthetic nanoclay, Laponite (LPN) together with a gelatin methacryloyl (GelMA) bioink and the development of a functional cell-instructive bioink. A nanocomposite bioink displaying enhanced shape fidelity retention and interconnected porosity within extrusion-bioprinted fibres was observed. Human bone marrow stromal cell (HBMSC) viability within the nanocomposite showed no significant changes over 21 days of culture in LPN-GelMA (85.60 ± 10.27 %), compared to a significant decrease in GelMA from 7 (95.88 ± 2.90 %) to 21 days (55.54 ± 14.72 %) (p

The mechanisms underlying the reactive component of pulmonary hypertension (PH) in heart failure (HF) are unclear. We examined whether resting systemic oxygen levels are related to pulmonary hemodynamics in HF.Thirty-nine HF patients underwent right heart catheterization. Subsequently, patients were classified as having: 1) no PH (n = 12); 2) passive PH (n = 10); or 3) reactive PH (n = 17). Blood was drawn from the radial and pulmonary arteries for the determination of PaO(2), SaO(2), PvO(2), SvO(2), and vasoactive neurohormones. PaO(2) and PvO(2) were lower in reactive PH versus no PH and passive PH patients (65.3 ± 8.6 vs 78.3 ± 11.4 mm Hg and 74.5 ± 14.0 mm Hg; 29.2 ± 4.1 vs 36.2 ± 2.8 mm Hg and 33.4 ± 2.3 mm Hg; P .05). SaO(2) and SvO(2) were lower in reactive PH versus no PH patients (93 ± 3% vs 96 ± 3%; 51 ± 11% vs 68 ± 4%; P .05), but not different versus passive PH patients. The transpulmonary pressure gradient (TPG) was inversely related to PaO(2), PvO(2), SaO(2), and SvO(2) in the reactive PH patients only (r ≤ -0.557; P .05). Similarly, plasma endothelin-1 correlated with PaO(2), PvO(2), SvO(2) (r ≤ -0.495), and TPG (r = 0.662; P .05) in reactive PH patients only.Systemic hypoxia may play a role in the reactive component of PH in HF, potentially via a hypoxia-induced increase in endothelial release of the vasoconstrictor endothelin-1.

Background Locally advanced laryngeal and hypopharyngeal cancers (LHC) represent a group of cancers for which surgery, laryngectomy-free survival (LFS), overall survival (OS), and progression-free survival (PFS) are clinically meaningful end points. Patients and methods These outcomes were analyzed in the subgroup of assessable LHC patients enrolled in TAX 324, a phase III trial of sequential therapy comparing docetaxel plus cisplatin and fluorouracil (TPF) against cisplatin and fluorouracil (PF), followed by chemoradiotherapy. Results Among 501 patients enrolled in TAX 324, 166 had LHC (TPF, n = 90; PF, n = 76). Patient characteristics were similar between subgroups. Median OS for TPF was 59 months [95% confidence interval (CI): 31–not reached] versus 24 months (95% CI: 13–42) for PF [hazard ratio (HR) for death: 0.62; 95% CI: 0.41–0.94; P = 0.024]. Median PFS for TPF was 21 months (95% CI: 12–59) versus 11 months (95% CI: 8–14) for PF (HR: 0.66; 95% CI: 0.45–0.97; P = 0.032). Among operable patients (TPF, n = 67; PF, n = 56), LFS was significantly greater with TPF (HR: 0.59; 95% CI: 0.37–0.95; P = 0.030). Three-year LFS with TPF was 52% versus 32% for PF. Fewer TPF patients had surgery (22% versus 42%; P = 0.030). Conclusions In locally advanced LHC, sequential therapy with induction TPF significantly improved survival and PFS versus PF. Among operable patients, TPF also significantly improved LFS and PFS. These results support the use of sequential TPF followed by carboplatin chemoradiotherapy as a treatment option for organ preservation or to improve survival in locally advanced LHC.

A randomized phase 3 trial of the treatment of squamous-cell carcinoma of the head and neck compared induction chemotherapy with docetaxel plus cisplatin and fluorouracil (TPF) with cisplatin and fluorouracil (PF), followed by chemoradiotherapy.We randomly assigned 501 patients (all of whom had stage III or IV disease with no distant metastases and tumors considered to be unresectable or were candidates for organ preservation) to receive either TPF or PF induction chemotherapy, followed by chemoradiotherapy with weekly carboplatin therapy and radiotherapy for 5 days per week. The primary end point was overall survival.With a minimum of 2 years of follow-up (or =3 years for 69% of patients), significantly more patients survived in the TPF group than in the PF group (hazard ratio for death, 0.70; P=0.006). Estimates of overall survival at 3 years were 62% in the TPF group and 48% in the PF group; the median overall survival was 71 months and 30 months, respectively (P=0.006). There was better locoregional control in the TPF group than in the PF group (P=0.04), but the incidence of distant metastases in the two groups did not differ significantly (P=0.14). Rates of neutropenia and febrile neutropenia were higher in the TPF group; chemotherapy was more frequently delayed because of hematologic adverse events in the PF group.Patients with squamous-cell carcinoma of the head and neck who received docetaxel plus cisplatin and fluorouracil induction chemotherapy plus chemoradiotherapy had a significantly longer survival than did patients who received cisplatin and fluorouracil induction chemotherapy plus chemoradiotherapy. (ClinicalTrials.gov number, NCT00273546 [ClinicalTrials.gov].).

Microglia, which are CNS-resident neuroimmune cells, transform their morphology and size in response to CNS damage, switching to an activated state with distinct functions and gene expression profiles. The roles of microglial activation in health, injury and disease remain incompletely understood due to their dynamic and complex regulation in response to changes in their microenvironment. Thus, it is critical to non-invasively monitor and analyze changes in microglial activation over time in the intact organism. In vivo studies of microglial activation have been delayed by technical limitations to tracking microglial behavior without altering the CNS environment. This has been particularly challenging during chronic neurodegeneration, where long-term changes must be tracked. The retina, a CNS organ amenable to non-invasive live imaging, offers a powerful system to visualize and characterize the dynamics of microglia activation during chronic disorders. This protocol outlines methods for long-term, in vivo imaging of retinal microglia, using confocal ophthalmoscopy (cSLO) and CX3CR1GFP/+ reporter mice, to visualize microglia with cellular resolution. Also, we describe methods to quantify monthly changes in cell activation and density in large cell subsets (200-300 cells per retina). We confirm the use of somal area as a useful metric for live tracking of microglial activation in the retina by applying automated threshold-based morphometric analysis of in vivo images. We use these live image acquisition and analyses strategies to monitor the dynamic changes in microglial activation and microgliosis during early stages of retinal neurodegeneration in a mouse model of chronic glaucoma. This approach should be useful to investigate the contributions of microglia to neuronal and axonal decline in chronic CNS disorders that affect the retina and optic nerve.

There is growing interest in understanding the properties of SiC-SiO2 interfaces, which can be formed by oxidation of silicon carbide surfaces. Here, we used variable cell shape ab initio molecular dynamics to investigate the structural and electronic properties of crystalline phases of silicon oxycarbide which could appear within such interfaces. We find that carbonoxygen single bonds may remain stable inside a silicon oxide matrix. For the Si2CO6 compound, there are at least two crystalline phases, both having large bulk modulii and wide bandgaps.

We performed a theoretical investigation on the effects of hydrogenation and dehydrogenation in the structural properties of amorphous silicon carbide (a-SiC). The calculations were carried out combining interatomic potentials with free volume Monte Carlo simulations. Our prototype amorphous silicon carbide systems contained as much as 85 000 atoms, allowing for a good statistical sampling. We addressed the role of hydrogen on the local and mid-range order of the material. We found that carbon atoms segregate, forming small clusters, embedded in an extensive silicon network. Ring statistics showed that hydrogenation increases the concentration of micro-voids in the structure and reduces its mid-range order. On the other hand, dehydrogenation recovers most of the original structural order.

We theoretically studied the phase transition between the cubic-diamond and β-Sn structures for the Si 0.5 Ge 0.5 alloy. We performed first principles calculations based on the density-functional theory, using the local-density approximation, and the variable cell shape molecular dynamics approach. The alloy was modeled using an ordered zincblende type lattice, and we obtained a transition pressure of 8.35 GPa. We also calculated the enthalpy curves at zero as well as at the transition pressure. At zero pressure, the enthalpy difference between the two phases is 0.016 Ry/atom, and there is a barrier of approximately 0.026 Ry/atom. At the transition pressure, the enthalpy barrier is still 0.018 Ry/atom, a sign of the strong first order character of this phase transformation.

We have performed systematical ab initio studies of the electronic and structural properties of the disordered phase of the Si1−xGex alloy. For the defect free alloy, we find that the Si–Si bond length has a tendency to maintain its natural value (x=0) all the way up to x>0.5, similarly to what is found experimentally. We also analyze the vacancy, and note, as expected for a structurally as well as chemically disordered solid, that there is no local symmetry around the vacancy site. Finally, we perform some studies of the alloy under pressure all the way up to 30 GPa, and find that the structure is highly distorted in some cases, indicating that an amorphous phase may be found in the pressure region of the diamond–β-tin phase transition.

The regioselective ozonolysis of methyl abietate to a stable epoxy-ozonide is described.

Condensation of 3, 6-dimethoxy-2-nitrobenzoyl chloride with L-proline methyl ester afforded amide 4, which underwent reductive cyclization with iron(II) sulfate and ammonium hydroxide to yield pyrrolobenzodiazepine 5. Oxidation of 5 with ammonium cerium(IV) nitrate led to the new heterocyclic quinone 6 in 53% overall yield.

Using first principles variable cell shape molecular dynamics, we predict a new structure for silica. This structure results from annealing {alpha} -quartz at pressures near a major phonon instability. The new phase is obtained by rotations of SiO{sub 4} tetrahedra producing edge-sharing SiO{sub 6} octahedra and SiO{sub 5} cuboids. This type of mechanism was proposed to account for structural transitions in silicate melts and amorphous solids under pressure. Here this mechanism is observed in a crystalline to crystalline phase transformation for the first time. The diffraction pattern of the new phase compares favorably with that of the unidentified intermediate crystalline phase found in silica during the amorphization. {copyright} {ital 1998} {ital The American Physical Society}

Using variable cell ab initio molecular dynamics, we have investigated hypothetical crystalline phases of silicon oxycarbide (Si1−xCxO2). We found that silicon oxide remains energetically stable with carbon incorporation, and the resulting oxycarbide material has a moderately large bulk modulus. Our results also indicated that there are at least two possible, and competing, crystalline phases for the Si2CO6. We discuss the possibility of those phases forming near the SiC/SiO2 interfaces.

AIMS The long-term clinical performance of drug-eluting stents (DES) coated with biodegradable polymers is poorly known. METHODS AND RESULTS A total of 274 coronary patients were randomly allocated to paclitaxel-eluting stents, sirolimus-eluting stents, or bare metal stents (2:2:1 ratio). The two DES used the same biodegradable polymers and were identical except for the drug. At three years, the pooled DES population had similar rates of cardiac death or myocardial infarction (9.0% vs. 7.1; p=0.6), but lower risk of repeat interventions (10.0% vs. 29.9%; p

The use of molecular methods to investigate microalgal communities of natural and engineered freshwater resources is in its infancy, with the majority of previous studies carried out by microscopy. Inefficient or differential DNA extraction of microalgal community members can lead to bias in downstream community analysis. Three commercially available DNA extraction kits have been tested on a range of pure culture freshwater algal species with diverse cell walls and mixed algal cultures taken from eutrophic waste stabilization ponds (WSP). DNA yield and quality were evaluated, along with DNA suitability for amplification of 18S rRNA gene fragments by polymerase chain reaction (PCR). QiagenDNeasy(®) Blood and Tissue kit (QBT), was found to give the highest DNA yields and quality. Denaturant Gradient Gel Electrophoresis (DGGE) was used to assess the diversity of communities from which DNA was extracted. No significant differences were found among kits when assessing diversity. QBT is recommended for use with WSP samples, a conclusion confirmed by further testing on communities from two tropical WSP systems. The fixation of microalgal samples with ethanol prior to DNA extraction was found to reduce yields as well as diversity and is not recommended.

The regioselective ozonolysis of methyl abietate to a stable epoxy-ozonide is described.

Condensation of 3, 6-dimethoxy-2-nitrobenzoyl chloride with L-proline methyl ester afforded amide 4, which underwent reductive cyclization with iron(II) sulfate and ammonium hydroxide to yield pyrrolobenzodiazepine 5. Oxidation of 5 with ammonium cerium(IV) nitrate led to the new heterocyclic quinone 6 in 53% overall yield.

FUNDAMENTO: Descrevemos as bases teóricas e o formato do Estudo PAINT - Intervenção percutânea com stents com eluição de paclitaxel ou sirolimus em polímero biodegradável comparados com stents sem recobrimento no tratamento de lesões coronárias de novo. OBJETIVO: Avaliar duas novas formulações de stents com eluição de paclitaxel ou sirolimus em comparação com um stent de estrutura metálica idêntica, porém sem recobrimento polimérico ou eluição de droga. MÉTODOS: O PAINT é um estudo randomizado, multicêntrico, de 3 braços, conduzido em centros terciários brasileiros, que incluiu 275 pacientes alocados para tratamento com os stents InfinniumR (paclitaxel), the SupralimusR (sirolimus) ou Milennium MatrixR (sem recobrimento) na proporção 2:2:1 ratio. Os pacientes apresentavam lesões coronarianas de novo em vasos nativos com um diâmetro entre 2,5 e 3,5 mm, passíveis de tratamento com um único stent com comprimento de 29 mm ou menos. O objetivo primário era comparar a perda tardia aos nove meses de ambos stents com paclitaxel- ou sirolimus versus a perda luminal dos stents convencionais de controle. Objetivos secundários importantes incluíam a comparação angiográfica entre os dois tipos de stents farmacológicos, bem como a análise da ocorrência de eventos clínicos adversos. RESULTADOS E CONCLUSÕES: O estudo PAINT apresenta um formato peculiar e único que permitiu a avaliação da segurança e eficácia de duas novas formulações de stents farmacológicos, com carreador polimérico biodegradável, e liberação de paclitaxel ou sirolimus, os quais foram comparados contra um stent metálico convencional (objetivo primário). Uma vez que os stents farmacológicos diferiram entre sí somente pela droga, mas eram idênticos nas suas outras características, os estudo também permitiu a comparação do efeito anti-restenótico entre sirolimus e paclitaxel (objetivo secundário). BACKGROUND: We describe the rationale and design for the PercutAneous INTervention with biodegradable-polymer based paclitaxel-eluting or sirolimus-eluting versus bare stents for de novo coronary lesions - PAINT trial. OBJECTIVES: To evaluate two novel formulations of paclitaxel-eluting stent and the sirolimus-eluting stent against a stent with the same metallic structure but without polymer coating or drug elution. METHODS: The PAINT is a multicenter 3-arm randomized trial, conducted in Brazilian tertiary institutions, which included 275 patients allocated for the InfinniumR paclitaxel-eluting stent, the SupralimusR sirolimus-eluting stent or the Milennium MatrixR bare metal stent in a 2:2:1 ratio. Patients had de novo coronary lesions in native vessels with a diameter between 2.5 and 3.5 mm, amenable for treatment with a single stent of 29 mm or less in length. The primary objetive was to compare the in-stent late loss at 9 months of both paclitaxel- and sirolimus-eluting versus the late loss of control bare metal stents. Important secondary objectives included the comparison in outcomes between sirolimus and paclitaxel stents, as well as the analysis of the incidence of major adverse cardiac events. RESULTS AND CONCLUSIONS: The PAINT trial had a unique design that allowed for the evaluation of the safety and efficacy profiles of two novel drug-eluting stent formulations, with a biodegradable-polymer carrier and releasing paclitaxel or sirolimus, which were compared against a bare metal stent (primary objective). As the drug-eluting stents differed by the drug, but were identical otherwise, the trial also allowed the comparison of the anti-restenosis effects of sirolimus versus paclitaxel (secondary objective). FUNDAMENTO: Describimos las bases teóricas y el formato del Estudio PAINT - Intervención percutánea con stents recubiertos de paclitaxel o sirolimus en polímero biodegradable comparados con stents no recubiertos en el tratamiento de lesiones coronarias de novo. OBJETIVO: Evaluar dos nuevas formulaciones de stents con liberación de paclitaxel o sirolimus en comparación con un stent de estructura metálica idéntica, pero sin recubierto polimérico o liberación de droga. MÉTODOS: El PAINT es un estudio randomizado, multicéntrico, de 3 brazos, llevado a cabo en centros terciaros brasileños, que incluyó a 275 pacientes destinados a tratamiento con los stents InfinniumR (paclitaxel), the SupralimusR (sirolimus) o Milennium MatrixR (no recubierto) en la proporción 2:2:1. Los pacientes presentaban lesiones coronarias de novo en vasos nativos con un diámetro entre 2,5 y 3,5 mm, pasibles de tratamiento con un único stent de hasta 29 mm de longitud. El objetivo primario era comparar la pérdida luminal tardía a los nueve meses de ambos stents con paclitaxel- o sirolimus versus la pérdida luminal de los stents convencionales de control. Los objetivos secundarios importantes incluían la comparación angiográfica entre los dos tipos de stents farmacológicos, así como el análisis de la ocurrencia de eventos clínicos adversos. RESULTADOS Y CONCLUSIONES: El estudio PAINT presenta un formato peculiar y único que permitió la evaluación de la seguridad y eficacia de dos nuevas formulaciones de stents farmacológicos, con transportador polimérico biodegradable, y liberación de paclitaxel o sirolimus, los que fueron comparados con un stent metálico convencional (objetivo primario). Dado que los stents farmacológicos diferían entre sí solamente por la droga, pero eran idénticos en sus otras características, el estudio también permitió la comparación del efecto antireestenótico entre sirolimus y paclitaxel (objetivo secundario). Universidade de São Paulo Faculdade de Medicina Instituto do Coração Hospital Universitário Cassiano Antonio de Moraes Hospital Santa Marcelina Natal Hospital Center Hospital Meridional Universidade Federal de São Paulo (UNIFESP) EPM Hospital Universitário Walter Cantidio PUC-RS Hospital São Lucas Rede D'Or de Hospitais Hospital Biocor São Camilo Hospital UNIFESP, EPM SciELO

Objectives: We tested two novel drug-eluting stents (DES), covered with a biodegradable-polymer carrier and releasing paclitaxel or sirolimus, which were compared against a bare metal stent (primary objective). The DES differed by the drug, but were identical otherwise, allowing to compare the anti-restenosis effects of sirolimus versus paclitaxel (secondary objective). Background: The efficacy of novel DES with biodegradable polymers should be tested in the context of randomized trials, even when using drugs known to be effective, such as sirolimus and paclitaxel. Methods: Overall, 274 patients with de novo coronary lesions in native vessels scheduled for stent implantation were randomly assigned (2:2:1 ratio) for the paclitaxel (n = 111), sirolimus (n = 106), or bare metal stent (n = 57) groups. Angiographic follow-up was obtained at 9 months and major cardiac adverse events up to 12 months. Results: Both paclitaxel and sirolimus stents reduced the 9-month in-stent late loss (0.54–0.44 mm, 0.32–0.43 mm, vs. 0.90–0.45 mm respectively), and 1-year risk of target vessel revascularization and combined major adverse cardiac events (P < 0.05 for both, in all comparisons), compared with controls. Sirolimus stents had lower late loss than paclitaxel stents (P < 0.01), but similar 1-year clinical outcomes. There were no differences in the risk of death, infarction, or stent thrombosis among the study groups. Conclusion: Both novel DES were effective in reducing neointimal hyperplasia and 1-year re-intervention, compared to bare metal stents. Our findings also suggest that sirolimus is more effective than paclitaxel in reducing angiographic neointima, although this effect was not associated with better clinical outcomes.© 2009 Wiley-Liss, Inc.

The regioselective synthesis of 2,3,4,5‐tetrahydro‐1H‐1,4‐benzodiazepin‐5‐ones by the Schmidt rearrangement of 1,2,3,4‐tetrahydro‐4‐quinolones with oxygen substituents at C‐8 is described.

We carried out a theoretical investigation of the structural properties of annealed $\ensuremath{\alpha}\ensuremath{-}\mathrm{SiC}$ and $\ensuremath{\alpha}\ensuremath{-}\mathrm{S}\mathrm{i}\mathrm{C}:\mathrm{H}.$ The calculations were performed using the free volume Monte Carlo method combined with interatomic potentials. Our prototype nanoparticle contained as much as 85 000 atoms which allows for a superior statistical sampling of the material. The results show that C atoms segregate, forming small clusters embedded in an extensive Si network. Si atoms are mostly contained in a single extensive network and a few small clusters. Unprecedented detailed ring statistics analysis shows that C clusters do not form strictly C rings and that the introduction of H increases the occurrence of microvoids in the structure. Moreover, the incorporation of H slightly reduces the chemical order in the material and, to a larger extent, reduces the midrange structural order. Hydrogen also relaxes bonding stress around atoms in the network. The results are consistent with the available experimental data.

The importance of the double bonds in the furan ring of avocadofurans with relation to their insecticidal activity was examined. The insecticidal activity of two naturally occurring avocadofurans, 2-(pentadecyl)furan and 2-(heptadecyl)furan, was compared to the toxicity of five tetrahydrofurans with alkyl chains at position 2 and varying side chains from 14 to 18 carbons. We found that eliminating the sites of unsaturation in the furan ring of avocadofurans significantly reduced the detrimental effects on the mortality and growth of the generalist insect herbivore Spodoptera exigua. In 7-day bioassays, S. exigua larvae were significantly more affected when fed a diet containing avocadofurans as compared to a larvae fed diet treated with the analogous tetrahydrofurans. Although larvae fed with the tetrahydrofurans showed reduced growth as compared to controls, larval mortality was not significantly increased. We conclude that the double bonds in the furan ring of avocadofurans play an important role in their insecticidal effects.

The insecticidal activity of five alkylfurans against the generalist insect herbivore beet armyworm, Spodoptera exigua, was examined. Two naturally occurring compounds, the avocadofurans 2-(pentadecyl)furan (1) and 2-(heptadecyl)furan (2), previously isolated from specialized avocado idioblast oil cells, and three homologues, 2-(tetradecyl)furan (3), 2-(hexadecyl)furan (4), and 2-(octadecyl)furan (5), were synthesized. Bioassays of alkylfurans 1-5 using a 9-day diet-incorporation initiated with neonates showed that all alkylfurans tested significantly increased S. exigua larval mortality and reduced larval weights, with maximal biological activity detected among the naturally occurring alkylfurans 1 and 2.

Sirolimus and Paclitaxel are well known anti-restenosis agents; they have been tested in different stents with different platforms and polymers. We aim to compare the neointimal inhibition efficacy of two drug eluting stents with identical platforms and biodegradable polymers, but with different

The distributions of oxidative capacities among type-identified muscle fibers in the developing cat diaphragm were examined by quantifying succinate dehy- drogenase (SDH) activity using a microdensitometric pro- cedure. Animals were studied during the first six weeks of postnatal development and compared to adults. Muscle fiber SDH activities were initially low during the first 2 postnatal wk, then increased to their highest values be- tween 3 and 6 wk. Thereafter, fiber SDH activities declined to adult values. At each age, the distributions of SDH activities for both type I and I1 fibers were unimodal. Thus, no objective basis exists for subclassifying type I1 fibers based on differences in oxidative capacity. Fibers could be subclassified as type IIA, JIB, or IIC based on the acid pH lability of ATPase staining. In neonates, approximately 90% of all fibers were classified as type IIC. Thereafter, the proportion of IIC fibers decreased while the propor- tions of type I, IIA, and IIB increased. Adult fiber type proportions were reached by 6 wk of age. The SDH activity of type I fibers was generally higher than that of type I1 fibers at all ages, although there was considerable overlap in the distributions of SDH activities among type I and I1 fibers. The SDH activity of type IIC fibers was also higher than that of either type IIA or IIB during development. Only in the adult diaphragm was the SDH activity of type IIA fibers higher than that of type IIB. At no age could type IIA, JIB, or IIC fibers be discriminated based solely on differences in oxidative capacity. (Pediatr Res 29: 586- 593,1991)

We evaluated 38 males who had psoriasis vulgaris for evidence of hypothalamus-pituitary-adrenal axis suppression (HPAS) during treatment with superpotent topical glucocorticosteroids. All men were treated with 49 g per week of either Betamethasone Diproprionate in an optimized vehicle or Clobetasol Proprionate ointment. Three methods used to assess HPAS were compared. Classic 8 a.m. plasma cortisol measurements, urinary-free cortisol, and 17-hydroxycorticosteroid determinations and gas chromatograph-mass spectrometry (GCMS) quantitation of urinary cortisol metabolites were compared. Values for all methods were obtained just prior to therapy and at days 4, 7, 14, and 21 during therapy and at day 28 after treatment was stopped for 7 d. Plasma cortisol measurements correlated well with other measures of HPAS. GCMS determination of urinary cortisol metabolites was slightly more sensitive at detecting HPAS than the other two methods. Persistent HPAS after day 7 was only appreciated by GCMS. Urinary-free cortisol and 17-hydroxycortisol was the least sensitive of the three methods. Analysis of urinary cortisol metabolites by GCMS may be most useful in the monitoring of HPAS resulting from use of topical glucocorticosteroid preparations.

Made available in DSpace on 2018-12-11T17:20:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-07-15 National Natural Science Foundation of China Secondary caries and hybrid layer degradation are two major challenges encountered in long-term resin-dentin bond stability. As a link between resin and dentin, adhesives that possess both antimicrobial and anti-proteolytic activities are in demand for eliminating bacteria-induced secondary caries and preventing hybrid layers from degradation. In the present study, a new quaternary ammonium methacryloxy silane (QAMS) prepared from sol-gel chemistry was incorporated into experimental adhesives to examine their antimicrobial effect and anti-proteolytic potential. This functional methacrylate resin monomer contains polymerizable methacryloxy functionalities as well as a positively-charged quaternary ammonium functionality with a long, lipophilic -C18H37 alkyl chain for puncturing the cell wall/membrane of surface-colonizing organisms. Antibacterial testing performed using agar diffusion test, live/dead bacterial staining and colony-forming unit counts all indicated that the QAMS-containing adhesives killed Streptococcus mutans and Actinomyces naeslundii in a dose-dependent manner via a predominant contact-killing mechanism. Gelatinolytic activity within the hybrid layers created by these adhesives was examined using in-situ zymography. Hybrid layers created with 0% QAMS-containing adhesive exhibited intense green fluorescence emitted by the hydrolyzed fluorescein-conjugated gelatin, with 4-fold increase in enzymatic activity compared with an experimental adhesive containing 5% QAMS. Taken together, incorporation of 5% QAMS in the experimental adhesive provides simultaneous antimicrobial and anti-proteolytic activities that are crucial for the maintenance of long-term resin-dentin bond integrity. Statement of Significance: Durability of resin-dentin interfacial bond remains a clinically-significant challenge. Secondary caries caused by bacteria and the degradation of hybrid layers via endogenous dentin proteases are two important contributors to the poor resin-dentin bond durability. The present study developed a new 5% QAMS-containing adhesive that provides simultaneous antimicrobial and dentin protease inhibition functions to extend the longevity of resin-dentin bonds. State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cariology and Endodontics West China Hospital of Stomatology Sichuan University The Dental College of Georgia Augusta University Department of Restorative Dentistry Institute of Science and Technology São Paulo State University UNESP São Jose dos Campos Department of Biomedical and Neuromotor Sciences DIBINEM University of Bologna – Alma Mater Studiorum State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Oral Diseases School of Stomatology The Fourth Military Medical University Department of Restorative Dentistry Institute of Science and Technology São Paulo State University UNESP São Jose dos Campos