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Hereditary angioedema (HAE) is rare disease characterized by recurrent, unpredictable, and debilitating attacks of subcutaneous/submucosal tissue swelling.1,2 The reported median age of onset of HAE due to C1 inhibitor deficiency/dysfunction (type 1/2; C1-INH-HAE) is 11-12 years.1,3 Treatment options for pediatric patients are limited, owing to low childhood diagnosis rates and low representation in investigative clinical trials.4 We present a multicenter, open-label, single-arm, phase 3 study (NCT01386658) investigating the use of icatibant, a bradykinin B2 receptor antagonist, to treat HAE attacks in pediatric patients with a confirmed diagnosis of C1-INH-HAE.5 In Part 1, patients (aged 2 to

Oil activity has generated severe problems of soil contamination. Different techniques have been employed for the removal of pollutants, which are mainly used separately as treatments, but if combi...

Mechanical and tribological properties of titanium nitride, zirconium nitride, and (TiN/ZrN)n multilayers were studied to examine the potential of Kelvin probe force microscopy (KPFM) to identify wear mechanisms. Crystalline structure, chemical composition, residual stress, and the mechanical properties showed that the coatings are iso-structural polycrystalline multilayers, with a reduction of grain size, crystallite size, and compressive stress; however, hardness increased with increase in the number of the bilayers. Pin-on-disc test was used for tribological evaluation, and wear tracks were analyzed using field-emission scanning electron microscopy/energy dispersed spectroscopy (FE-SEM/EDS) and KPFM. The increase in mechanical properties generated predominantly abrasive wear mechanisms. Abrasive and adhesive wear mechanisms differentiated by KPFM demonstrated that fragile wear mechanisms presented differences in capacitance and surface potential and that the method is sensitive when the adhered material presents differences in chemical composition. We have demonstrated KPFM to be a promising technique to study tribo-oxidation processes, providing experimental evidence to understand the wear mechanisms at nanometric scales.

A new family of push-pull biphenyl-azopyrrole compounds 3b-g and 4b-d was efficiently obtained via a Suzuki cross-coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) or 3-(4'-iodophenyl-azo)-1,2,5-trimethyl pyrrole (2a) and 4'-substituted phenyl boronic acids in excellent yields. The influence of the π-biphenyl backbone and pyrrole pattern substitution was correlated with their optical properties. Solvatochromic studies via UV-visible spectrophotometry revealed that the inclusion of a 4'-nitro-biphenyl fragment favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Likewise, optical band-gaps were estimated by means of electronic absorption spectra and correlated with TD-DFT studies. The pyrrole pattern substitution and the π-conjugated backbone exhibit a clear influence on their thermal isomerization kinetics at room temperature. In all cases, biphenylazo-pyrrole compounds lead to the formation of J-type aggregates in binary MeOH : H2O solvents. Under these conditions, compounds 3b-c undergo a water-assisted cis-to-trans isomerization at room temperature.

Since the introduction of magnetic extraction sorbents in 1996 by Towler et al., magnetic nanoparticles (m-NPs) have gained importance as sorbents in sample preparation procedures, especially in the so-called magnetic-dispersive solid-phase extraction (m-dSPE), as a result of the simplification of the extraction procedure, which saves time and efforts. Despite the fact that m-NPs have been used in some cases as synthesized, without any further modifications, they do not generally have enough extraction capacity for organic analytes and have a high tendency to aggregate as well as a high chemical reactivity, which results in a loss of dispensability and magnetism. As a result, they are generally coated with different materials (i.e., silica, surfactants, ionic liquids, antibodies or aptamers, polymers, carbon nanotubes, molecular organic frameworks, etc. or their mixtures) which enable them to selectively and quantitatively extract a good number of organic analytes from different matrices. The aim of this chapter is to review the current state-of-the-art of the application of coated/functionalized m-NPs in sample pretreatment, especially in m-dSPE, providing a critical and updated overview of the different m-NP coatings and their effectiveness for organic analyte extraction.

Background and importance Flecainide is commonly used for conversion of recent onset ( Aim and objectives To evaluate successful cardioversion in patients treated with vernakalant or oral flecainide with recent onset AF attending the ED. Material and methods A single centre, non-randomised, retrospective study was conducted in patients diagnosed with recent onset AF in the ED. Vernakalant was approved by the Pharmacy and Therapeutics Committee in June 2018. The flecainide group included patients who attended the ED from January to June 2018 and the vernakalant group from July 2018 to October 2020. Patients received intravenous vernakalant (3 mg/kg followed by 2 mg/kg if necessary) or oral flecainide (200–300 mg). Sociodemographic and clinical variables were obtained from electronic health records. The primary endpoint was percentage of patients that achieved sinus rhythm in the ED. Secondary outcomes were conversion time to sinus rhythm, length of stay in the ED and percentage of patients that maintained sinus rhythm after 3 months of cardioversion. Results 63 patients were included in the study; 20 received vernakalant and 43 flecainide. Median age was 59 years (IQR 53–66) and 63% were men. Baseline characteristics were similar in both groups. Cardioversion was successful in 80% of patients treated with vernakalant and in 64.3% treated with flecainide (p=0.21). Conversion time was 13 min in the vernakalant group versus 489 min in the flecainide group (p Conclusion and relevance Vernakalant achieved a higher cardioversion rate than oral flecainide in recent onset AF patients. Conversion was significantly faster and was associated with shorter hospital stay. However, long term effectiveness was similar between both drugs, as well as the safety profile. References and/or acknowledgements Conflict of interest No conflict of interest

International audience; A method for the synthesis of a new phosphine-free [N,N,O]-tridentate Schiff base ligand L1 using the 2-Ferrocenyl-2-thiazoline as scaffold was developed. The 1,2-disubstituted ferrocene-based ligand was assembled using as key strategy the directed ortho-metalation (DoM) in 2-ferrocenyl-2-thiazoline. L1 was successfully obtained in 83% of overall yield after two-step synthesis. The coordination ability of L1 towards Ru(II) was evidenced and the resulting complex was characterized by IR, UV-vis and EPR. Its catalytic performance was tested in transfer hydrogenation of a variety of substrates giving moderate to excellent conversions.

Background and importance Ibrutinib is a tyrosine kinase inhibitor indicated for the treatment of chronic lymphocytic leukaemia (CLL) among other pathologies. Aim and objectives To assess the frequency and severity of adverse events (AEs) in CLL patients treated with ibrutinib. Material and methods This was an observational, retrospective, descriptive study including all patients aged >18 years old diagnosed with LLC treated with ibrutinib 420 mg/24 hours in our hospital. The study period was July 2015–September 2019. Variables collected were sex, age, diagnosis and cytogenetics, previous treatment lines, duration of treatment, AEs, dose adjustment, temporal discontinuations and definitive suspensions. AEs were classified following the National Institute Cancer (NCI): Common Terminology Criteria for Adverse Events (CTCAE) V.5.0. Data were collected from the electronic clinical history, electronic prescribing software and drug therapy follow-up. Results Thirty-one patients were included (9 women and 22 men) with an average age of 72 years (range 48–90). Poor prognostic cytogenetics was presented in 71% of patients: 45.16% had del (17p), 12.90% had del (11q) and 12.90% had both. Ibrutinib was prescribed as firstline treatment in 10 patients and as rescue treatment in 21 patients that had a median of 1 previous line (range 1–5). Median length of treatment was 12.7 months (range 2–42.3). Nine patients suspended ibrutinib permanently: progression (n=5), death (n=2), grade 3/4 AEs (n=1, haemorrhagic) and alogenic transplant (n=1). In addition, six patients discontinued ibrutinib because of grade 3/4 neutropenia (n=3), respiratory infections (n=2) and bleeding grade 3/4 (n=1). Twenty-two patients were continuing ibrutinib treatment when the study was closed. AEs grade 1/2 included musculoskeletal AEs (muscle cramps (n=3), arthralgia (n=4), musculoskeletal pain (n=3)), haematologic AEs (neutropenia (n=1), thrombocytopenia (n=1)), gastrointestinal AEs (diarrhoea (n=1)) and infections (urinary (n=1), periferic oedema (n=1)). One patient was diagnosed with atrial fibrillation and another with hypertension that required treatment. Conclusion and relevance In our patients, ibrutinib had an adequate safety profile, highlighting haemorrhage as the most serious AE. Periodic follow-up of patients is necessary to assess adverse reactions and the need for temporary suspension in patients. References and/or acknowledgements No conflict of interest.

Background: Real-life data on single-tablet regimen (STR) dolutegravir/abacavir/lamivudine (DTG/ABC/3TC) is scarce, and concerns about DTG neuropsychiatric adverse events (NP-AEs) have recently arisen. Objective: To explore the effectiveness and safety, in particular NP-AEs, of DTG/ABC/3TC in a cohort of HIV-1 adult infected patients. Pill burden, adherence to this STR, and the impact of switching on costs were also evaluated. Methods: This was an observational, retrospective study. The study population included antiretroviral therapy (ART)-naive and treatment-experienced (TE) patients who started DTG/ABC/3TC between February 1, 2016, and October 31, 2016. Effectiveness and safety were analyzed at week 48 (W48) by intention-to-treat analysis. The Cox regression model was used to investigate predictors of DTG/ABC/3TC discontinuation. Results: A total of 253 patients were included (44 ART naïve, 209 TE). At W48, the proportion of patients with virological suppression was 72.7% (95% CI = 58.4-87.0) in ART-naive patients, 85.6% (95% CI = 80.3-90.9) in previously suppressed TE patients, and 86.4% (95% CI = 65.1-97.1) in previously not suppressed TE patients. The rate of protocol-defined virological failure was 4.3%. The incidence of AEs was higher in the subgroup of ART-naive patients (56.1% vs 39.0%), with a rate of interruptions for this reason of 13.6% and 7.6%, respectively. The incidence of NP-AEs was 20.6%, with 3.9% of patients requiring discontinuation. Patients who had switched from a raltegravir-containing regimen discontinued DTG/ABC/3TC because of AEs more frequently (relative risk = 2.83; 95% CI = 1.04-7.72; P = 0.041) in the multivariate analysis. After switching to DTG/ABC/3TC, the median pill burden was reduced from 3 to 1 and the proportion of patients with an adherence

We report the synthesis of a series of ferrocene amphiphilic donor–π–acceptor dyes, with the general formula (Fc-CHCH-HetNC16H33)+ X− [where: Fc behaves as the donor group, a double bond as the π bridge, and 2-,4-pyridinium and 4-quinolinium as the potent acceptor groups (2a–b and 4, X = Br− or BF4−)], in good overall yields. Together with their neutral counterparts (6a–b and 7), the photophysical and electrochemical properties of these compounds were investigated by means of UV-Vis spectroscopy and cyclic voltammetry. The optical and electrochemical band gaps of these dyes were calculated, which indicated that 4 has the lowest bandgap value. Time-dependent DFT calculations indicate that the lowest energy absorption band displayed for these compounds has mainly metal-to-ligand charge transfer character, with the HOMO–LUMO electronic transition being the main contribution.

Hard coatings are continuously improved due to the industrial needs and urgency to reduce the environmental impact of manufacturing processes. For these reasons, scientists seek hard coatings resistant to high mechanical and thermal loads under extreme working conditions (i.e., dry machining), which is why Hf and other rare earth metals have been added to the metastable c-AlxTi(1-x)N nitrides. In the present investigation, Hf-doped c-Al0.64Ti0.36N was deposited in a 2- & 3-axis rotation system using a semi-industrial coater. For this purpose Hf-pins were fixed in Al/Ti targets that produced coatings with ~0.2 at. % Hf-contents homogeneously dispersed. Hf effect on the crystalline state and microstructure, mechanical properties, high-temperature resistance, and the tribological performance of the coating in an Ar-jet at 900 °C were analyzed. It was found that the Hf-doped Al0.64Ti0.36N 5.07 μm thick-layer was mainly cubic fcc + traces of the hcp phases and displayed higher mean hardness (36 GPa) and E-module (416 GPa) than the coating without Hf (h = 32 GPa and E = 402 Pa). The Hf-containing nitride oxidizes dynamically during the high-temperature tribology testing and produces t-Ti2O3 & o-Al2TiO5 after short exposure periods (2.5–5 min), which strongly affected the CoF, before evolving to thermodynamically stable α-Al2O3 & anatase TiO2 between 10 & 30 min in the Ar-flow, thus resulting in the relative stability of the CoF. The mechanical evaluation of the oxidized coatings indicates that a specific oxide thickness must be reached to avoid catastrophic system damage at high normal loads.

Biodegradation of oil-contaminated sediments (OCS) in sediment microbial fuel cells (SMFC) is limited by several factors such as adapted microorganisms to degrade OCS, low conductivity and organic matter content, sluggish cathodic O2 reduction reaction (ORR), among others. The use of a birnessite/Carbon Fabric (CF) cathode improves the O2 reduction in SMFC. Oil-contaminated sediments amended with chitin (commercial analytical grade (CC) and dried natural shrimp shells (NC)) allows faster anaerobic biodegradation in the anolyte by the indigenous bacteria coming in the initial OCS, without further growth media. The SMFC containing the unmodified OCS produces a maximum power output of 5 mW m−2 in contrast to 62 mW m−2 and 178 mW m−2 of that SMFC containing CC and NC, respectively. High-power output of SMFC is the result of minimizing internal resistance by combining the following key factors: a) saturated air 0.8 M Na2SO4 catholyte at pH 2, b) the use of a birnessite/CF-cathode, and c) the presence of bacterial groups enriched on the anode biofilm as Deltaproteobacteria and Bacteroidetes, additional to other groups such as Aminocenantia depending on the source of chitin. The pH of the catholyte strongly modifies the power production of SMFC; a detailed discussion is included in this paper.

Background Obinutuzumab is an anti-CD20 monoclonal antibody approved in combination with chlorambucil for patients with chronic lymphocytic leukaemia (CLL) and comorbidities, making them unsuitable for full-dose fludarabine-based therapy. Purpose To analyse the safety and effectiveness of obinutuzumab combined with chlorambucil as first-line treatment in our hospital. Material and methods Observational, retrospective, descriptive study. Inclusion criteria: adults (>18 years) that initiate treatment with obinutuzumab-chlorambucil. Study period: January 2017 to September 2018. Demographic variables: gender, age; clinical variables: diagnose and cumulative illness rating scale (CIRS); and therapy-related: adverse events and suspension. Safety was evaluated in all patients that received at least one obinutuzumab dose by analysing adverse events (AE) from clinical records, treatment delays and/or concomitant medication required. AE are classified following the 5.0 version of National Institute Cancer: Common Terminology Criteria for Adverse Events. Effectiveness was evaluated following International Workshop CLL; Halleck 2008 criteria a minimum of 3 months after the end of treatment. Results Seven patients were included (four male and three female), median age: 72 years (rank 67–82). Median CIRS punctuation: 9 (rank 6–11). All patients received premedication with corticosteroids, antipyretic and antihistaminic to avoid infusion-related reactions (IRRs) and allopurinol as prophylaxis for tumour lysis syndrome. During the first infusion, two patients presented hypertension, abdominal pain and cold as grade 1–2 IRRs requiring temporary interruption. IRRs were not recorded in the following perfusions. Four patients presented haematologic toxicity, grade 3 neutropenia, requiring G-CSF, treatment delay was only required in one of them. Other AE: grade 2 anaemia treated with erythropoietin (n=1), grade 2 thrombocytopenia (n=1), respiratory infections (n=2; one patient with hypogammaglobulinaemia previous to treatment required hospital admission and treatment suspension). By the time the study was finished, effectiveness was evaluated in four up to six patients that finished treatment: complete response (n=3) and partial response (n=1). Conclusion In our experience, the obinuzumab-chlorambucil scheme presented a good safety profile in patients with comorbidities. The main AE were IRRs: limited to first administration that did not require treatment suspension; and neutropaenia, which was the most frequent haematologic toxicity. Regarding response, a continuous monitoring is necessary to confirm long-term effectiveness. References and/or acknowledgements No conflict of interest.

Luminescent carbon nanodots (CNDs) have been obtained by hydrothermal processing of ascorbic acid (AA) and ethanolamine (EN). The resulting N-doped carbon nanostructures exhibit interesting and tunable emission capabilities with a dual behavior as down-converters and more importantly, as up-converting quantum dots. Herein, we also evaluate the optical response of these CNDs to selectively generate highly reactive oxidative hydroxyls ( OH) upon irradiation with different light-emitting diodes (LEDs) in the visible–NIR range. Finally, the role of the N-doped CNDs as nano-sensitizers to maximize the solar light harvesting and expand the photo-catalytic response of a commonly used UV-active catalyst such as TiO2 was successfully tested in the degradation of an organo-chlorinated compound under visible light.

What is known and objectives Inadequate management of chronic medication puts patients at risk and causes unnecessary suspension of surgical procedures. The objective of the study was to calculate the rate of cancellation of elective surgical procedures due to inadequate management of chronic medications and to analyse the underlying causes of cancellation. Methods We designed an analytic, observational, retrospective study of all elective surgical procedures performed from July to October 2017 in a tertiary hospital. The main variable was the percentage of surgeries cancelled owing to inadequate management of chronic medications. Other variables recorded included demographic characteristics, time between the preanaesthesia evaluation and surgery, drug involved, and the reason for incorrect management of the medication. Results During the study period, 5415 surgical procedures were programmed, and 793 (14.6%) were cancelled. Cancellations due to inadequate patient preparation accounted for 5.3% (42 cases), and 19 were related to incorrect medication management (2.4% of the total number of cancellations). The 19 patients, who were mostly men (73.7%), had a median age of 76 years (IQR 68-81). The drugs involved were acenocoumarol (6), enoxaparin (4), clopidogrel (4), direct-acting oral anticoagulants (2), acetylsalicylic acid (1), tocilizumab (1) and leflunomide (1). The reasons for drug mishandling were poor understanding of the anaesthesiology recommendations (15) and lack of a preanaesthesia evaluation (4). What is new and conclusion Inadequate management of chronic medications (2.4%) is not the most frequent reason for cancellation, although it is one of the easiest to avoid. Based on our results, starting in October 2017, the Pharmacy Department began to offer a pharmaceutical service to patients with doubts about the preoperative management of chronic medications.

Background Trastuzumab emtansine (T-DM1) was studied in the EMILIA trial as a second line of treatment for HER-2 positive metastatic breast cancer (MBC), following the trastuzumab-taxane first-line scheme. However, the demonstration of the superiority of pertuzumab-trastuzumab-taxane as the first line of MBC after the CLEOPATRA trial, means that T-DM1 is currently used in a different scenario from the one studied in the EMILIA. Purpose Our objective is to provide more real-world data of the efficacy of T-DM1 in specific subgroups of patients, in order to know which patients will benefit more from T-DM1 therapy. Material and methods A retrospective, longitudinal, observational study was conducted between December 2016 and September 2017. Patients who started T-DM1 for MBC between October 2014 and September 2017 were included. Patients who had received T-DM1 in clinical trials were not included. Data collected were demographic data, previous treatments for MBC, Eastern Cooperative Oncology Group (ECOG) status at baseline, hormone receptor status, dates of therapy start, progression and discontinuation, and adverse events. Subsequently, data were analysed with Stata14®. Results Thirty-one patients were included. 32.3% of them had a hormone-sensitive tumour. The median of previous treatments for the MBC was 2 (range 0–6). Median progression-free survival (PFS) for all patients was 4.14 months (9.6 months in EMILIA). 38.7% of patients had a serious haematological adverse event. 19.3% had previously received trastuzumab-pertuzumab-taxane. They achieved a median PFS of 2.86 months, compared to 4.47 months for non-treated patients. 35.5% of patients were previously treated with more than one previous scheme. They had a median PFS of 3.88 months, compared to 6.37 for more pretreated patients. Conclusion There may be a profile of patients who respond in an excellent manner to T-DM1, as others appear not to have a good response. This could be related to the number of previous regimens received and number of different regimens. It seems not to be related, in our study, with ECOG or age at the beginning of treatment. Characterising patients prior to initiating therapy may be complex but advisable to obtain optimal results with the therapy chosen. No conflict of interest

International audience; A pyrrolyl-containing [N-P]-ligand (L1) and [Ru] were evaluated as catalytic system in transfer hydrogenation reaction of ketones. A comparison between microwave irradiation vs conventional heating conditions indicates that MW can be successfully used as energy source, improving the reaction time. The L1/Ru(II) proved to be an active, efficient and robust catalytic system. The scope of this catalytic system was evaluated using a diversity of substrates that include electron-withdrawing and electron-donor groups achieving a range of 65 to 95% conversion. Moreover, the catalytic system showed good activity even with highly sterically hindered ketones.

Oxidative stress is a major factor explaining sperm dysfunction of spermatozoa surviving freezing and thawing and is also considered a major inducer of a special form of apoptosis, visible after thawing, in cryopreserved spermatozoa. To obtain further insights into the link between oxidative stress and the induction of apoptotic changes, stallion spermatozoa were induced to oxidative stress through redox cycling after exposure to 2-methyl-1,4-naphthoquinone (menadione), or hydroxyl radical formation after FeSO4 exposure. Either exposure induced significant increases (p amp;lt; 0.05) in two markers of lipid peroxidation: 8-iso-PGF(2) and 4-hydroxynonenal (4-HNE). While both treatments induced changes indicative of spermptosis (caspase-3 activation and decreased mitochondrial membrane potential) (p amp;lt; 0.01), menadione induced sperm necrosis and a dramatic reduction in motility and thiol content in stallion spermatozoa. Thus, we provided evidence that oxidative stress underlies spermptosis, and thiol content is a key factor for stallion sperm function. Funding Agencies|Secretaria de Estado de Investigacion, Desarrollo e Innovacion [AGL2013-43211-R, IJCI-2014-21671]; Ministerio de Educacion Cultura y Deporte [FPU13/03991]; Ministerio de Economia y Competitividad-FEDER [AGL2013-43211-R]; Junta de Extremadura-FEDER [IB16030, GR 15029]; Swedish Research Councils [521-2011-6353]; Formas [221-2011-512]

Univ Sao Paulo State UNESP, Araraquara Sch Dent, Dept Diag &Surg, BR-14801903 Araraquara, SP, Brazil

Organic films with a thickness of few nanometers are potentially useful components in many practical and commercial applications such as sensors, detectors, displays and electronic circuit components. In this context, the Langmuir-Blodgett (LB) method is one the most promising techniques for preparing these films.In this work, we report the synthesis and characterization of three new amphiphilic organometallic compounds with ferrocene units, which consist of one ferrocenyl aminocarbene with the general formula FcC=Cr(CO)5NH(CH2)15CH3, and two ferrocenyl amides with the general formula FcC=MNH(CH2)15CH3 where M = S or Se. These new derivatives have been synthesized to study the influence of long alkyl side chain and the hydrophilic head on the film organization behavior at the air-water interface.The Langmuir-Blodgett (LB) technique was focused for building ordered nanostructures in molecular assemblies of ferrocenyl derivatives, which are apt to form a stable and transferable monolayer film. The π-A isotherm, hysteresis, Brewster angle microscopy (BAM) and film stability were used to characterize the behavior of a monolayer film at the air-water interface. Z- type LB films were prepared from molecular monolayers which were transferred onto glass substrates. These films were characterized by atomic force microscopy (AFM), UV-Visible spectra and X-ray diffraction (DRX) techniques.

Microbiological activities are essential in the bioremediation of polluted soils. The enzymatic activities of microorganisms are usually used as a biological indicator of soil health. The aim of this work was to observe the catalase, acid phosphatase (AcP), and alkaline phosphatase (AlP) activities in soil that was amended with agro-industrial by-products and macronutrients during the process of total petroleum hydrocarbon (TPH) removal. To this end, microcosm tests were performed with soil and agro-industrial by-products ratios of 100:2:2, for soil:sugarcane bagasse pith:filter cake mud (SSF); 100:2, for both soil:sugarcane bagasse pith (SS); and for soil filter cake mud (SF). The macronutrients—carbon, nitrogen, and phosphorus—in the experimental treatments were adjusted to 100:10:1 with a solution of NH4NO3 and K2HPO4. The best TPH removal (51.4%) was obtained with SSF at 15 days. In addition, a significant correlation was observed between TPH removal and AlP as well as AcP (r = 0.74, p

International audience; An efficient method to obtain chiral 1,2-disubstituted ferrocenyl ligands has been developed. The introduction of planar chirality was accomplished by using 2-thiazoline as an ortho-directing lithiation group, and moreover, these kinds of ligands possess a central chirality from the amino alcohol used in their synthesis. The X-ray analysis and DFT calculations confirmed the diastereoselectivity of ortho-lithiation and the configuration of the planar chirality. The ability of these new bidentate [N,S]-ferrocene ligands to act in Pd-catalyzed asymmetric allylic alkylation has also been demonstrated and compared with their oxazoline counterparts.

To investigate the mechanisms inducing sperm death after ejaculation, stallion ejaculates were incubated in BWW media during 6 h at 37°C. At the beginning of the incubation period and after 1, 2, 4 and 6 h sperm motility and kinematics (CASA), mitochondrial membrane potential and membrane permeability and integrity were evaluated (flow cytometry). Also, at the same time intervals, active caspase 3, hydrogen peroxide, superoxide anion (flow cytometry) and Akt phosphorylation (flow cytometry) were evaluated. Major decreases in sperm function occurred after 6 h of incubation, although after 1 h decrease in the percentages of motile and progressive motile sperm occurred. The decrease observed in sperm functionality after 6 h of incubation was accompanied by a significant increase in the production of hydrogen peroxide and the greatest increase in caspase 3 activity. Additionally, the percentage of phosphorylated Akt reached a minimum after 6 h of incubation. These results provide evidences that sperm death during in vitro incubation is largely an apoptotic phenomena, probably stimulated by endogenous production of hydrogen peroxide and the lack of prosurvival factors maintaining Akt in a phosphorylated status. Disclosing molecular mechanisms leading to sperm death may help to develop new strategies for stallion sperm conservation.

The objective of this study was to evaluate the effect of different fat sources in finishing diets on performance of feedlot steers. Twenty steers, with average age of 20 months and initial live weight of 260 ± 41.3 kg, were feedlot fed during 126 days. The animals received corn silage as roughage and the tested concentrates were: basic concentrate (BC); basic concentrate + whole rice bran and rice oil (WRB); basic concentrate + 3 % of fatty acids calcium salts (M3) and basic concentrate + 6 % of fatty acids calcium salts (M6). Each treatment had animals with the following genetic group: 1 pure Charolais (CH), 1 pure Nellore (NE), 2 11/16 CH 5/16 NE, 1 21/32 NE 11/32 CH. No significant differences were observed for crude protein, digestible energy, neutral and acid detergent fibers intakes. The animals that consumed 6 % of fatty acid calcium salts presented higher ether extract intake (0.77 kg/day), while those that consume 3 % or whole rice bran and oil showed intermediate value (0.51 kg/day) and the ones that consumed basic concentrated presented lower value (0.25 kg/day). Similar averages were observed for average daily weight gain (1.142, 1.199, 1.365 and 1.391 kg/day, for BC, WRB, M3 and M6, respectively) and final weight (421 kg).

The development and characterization of a hybrid hydrogel based on chitosan (CS) and poly(vinyl alcohol) (PVA) chemically cross-linked with epichlorohydrin (ECH) is presented. The mechanical response of these hydrogels was evaluated by uniaxial tensile tests; in addition, their structural properties such as average molecular weight between cross-link points (Mcrl), mesh size (DN), and volume fraction (v(s)) were determined. This was done using the equivalent polymer network theory in combination with the obtained results from tensile and swelling tests. The films showed Young's modulus values of 11 ± 2 MPa and 9 ± 1 MPa for none irradiated and ultraviolet (UV) irradiated hydrogels, respectively. The cell viability was assessed using Calcein AM and Ethidium homodimer-1 assay and environmental scanning electron microscopy. The 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan thiazolyl blue formazan (MTT Formazan assay) results did not show cytotoxic effects; this was in good agreement with nuclear magnetic resonance and fourier transform infrared spectroscopies; their results did not show traces of ECH. This indicated that after the crosslinking process, there was no free ECH; furthermore, any possibility of ECH release in the construct during cell culture was discarded. The CS-PVA-ECH hybrid hydrogel allowed cell growth and extracellular matrix formation and showed adequate mechanical, structural, and biological properties for potential use in tissue engineering applications.

At present, the only repeatable means of selecting the sex of offspring is the Beltsville semen sorting technology using flow cytometry (FC). This technology has reached commercial status in the bovine industry and substantial advances have occurred recently in swine and ovine species. In the equine species, however, the technology is not as well developed. To better understand the changes induced in stallion spermatozoa during the sorting procedure, pooled sperm samples were sorted: sperm motility and kinematics were assessed using computer assisted sperm analysis, sperm membrane integrity was assessed using the YoPro-1 assay, while plasmalemmal stability and lipid architecture were assessed using Merocyanine 540/SYTOX green and Annexin-V, respectively. Lipid peroxidation was also investigated with the probe Bodipy(581/591)-C11. All assays were performed shortly after collection, after incubation and after sex sorting using FC. In order to characterize potential molecular mechanisms implicated in sperm damage, an apoptosis protein antibody dot plot array analysis was performed before and after sorting. While the percentage of total motile sperm remained unchanged, sex sorting reduced the percentages of progressive motile spermatozoa and of rapid spermatozoa as well as curvilinear velocity (VCL). Sperm membranes responded to sorting with an increase in the percentage of YoPro-1 positive cells, suggesting the sorted spermatozoa had a reduced energy status that was confirmed by measuring intracellular ATP content.

Gold nanorods coated with a uniform titanium dioxide nanoshell have been prepared and used as glucose-oxidase surrogates. Remarkably, this core–shell photocatalytic nanostructure has been able to induce complete oxidation of glucose at near room temperature (32–34 °C) in a wide range of pH values with the aid of a near-infrared (NIR) irradiation source. In contrast, the uncoated gold nanorods exhibit negligible photo-oxidation response under identical experimental conditions thereby proving the photoactivity of the titania shell towards glucose oxidation. The process takes place via in situ photo-generation of singlet oxygen or hydroxyl radicals as reactive oxidative species (ROS). This underlines the role played by the core nanorods as plasmonic light harvesters in the NIR range and constitutes the first example of a NIR-activated enzyme-like catalyst.

International audience; We herein report the synthesis and catalytic application of a new family of [N\P], ligands based on the pyrrole ring with alpha-phosphine or phosphole units. Their palladium complexes (3a-d) were obtained in very good yields and their catalytic properties were evaluated in the direct intramolecular arylation to obtain both benzopyranones and phenanthridinones. The air stable complex 3a exhibited the best catalytic performance of this series of complexes, using 1 mol% of catalyst in combination with microwaves to promote this reaction.

Sedimentation of spermatozoa occurs during long-term liquid storage and this may produce deleterious changes. Our aim was to apply gelatine supplementation during long-term pre-freezing storage of bear sperm, applying final dilution and 6% glycerol at room temperature and cool in straws. We tested four models of sperm storage using a 1:1 dilution in TTF-ULE-Bear extender (TesT-fructose-egg yolk-glycerol 6%): (i) second 1:1 dilution at room temperature (RT), cooling at 5°C in a tube and final dilution (100 × 10 sperm ml) (Standard); (ii) final dilution at RT and cooling in a tube (FD-Tube); (iii) final dilution at RT and cooling in 0.25 ml plastic straw (FD-Straw); and (iv) final dilution at RT in extender supplemented with 1.5% gelatine (Gelatine) and cooling in a 0.25 ml plastic straw. A Standard sample was stored at 5°C for 1 hr (Control); the rest of the samples (Standard, FD-Tube, FD-Straw, Gelatine) were stored for 24 or 48 hrs before freezing (100 × 10 sperm ml, glycerol 6%). The quality of the samples was assessed for motility by CASA, and viability (SYBR-14/propidium iodide-PI-; VIAB), acrosomal status (PNA-FITC/PI; iACR) and apoptotic status (YO-PRO-1/PI; YOPRO-) by flow cytometry. At pre-freezing, after 48 hr, Gelatine showed significantly higher viability (for VIAB and YOPRO-) and progressiveness (PM, LIN and STR). At 48 hr, Gelatine showed similar YOPRO-, iACR, LIN, STR and ALH respect to Control. At both 24 and 48 h post-thawing, Gelatine sample had similar scores for YOPRO-, iACR, LIN, STR, WOB and VIAB (only 24 hr) when compared with Control, and lower for TM, PM, rapidPM, VAP and ALH. No differences were found among others experimental groups with respect to Control. In conclusion, gelatine could be a suitable alternative to preserve the viability and progressive motility of brown bear ejaculates during long-term pre-freezing storage at 5°C., This work was supported by MICINN (CGL2013-48255-R) and CANTUR S:A: Elena López-Urueña was supported by a PhD fellowship (ORDEN EDU/330/2008, co-finaced by Junta de Castilla y León and European Social Fund).

Contents: Lipids were extracted from ejaculated spermatozoa from seven individual stallions to distinguish neutral lipids (NL) and polar lipids (PL) and determine their variation among stallions and their relationship with sperm quality and sperm susceptibility to lipid peroxidation. The isolated fatty acids were correlated with sperm quality (membrane integrity, mitochondrial membrane potential (ΔΨm) and expression of active caspases) and the sensitivity of the sperm plasma membrane to LPO. The miristic (C14: 0), palmitic (C16: 0), stearic (C18: 0) and oleic (C18: 1n9) acids were predominant among the NLs. Within the phospholipid fraction, the docosapentanoic acid (C22: 5n6) was dominant, albeit varying among stallions. Surprisingly, the percentage of polyunsaturated fatty acids was positively correlated with sperm quality and a low propensity for LPO, probably because these particular fatty acids provide a higher fluidity of the plasma membrane. The stallion showing the poorest sperm membrane integrity plus a high level of LPO in his ejaculate had a lower percentage (p less than 0.05) of this fatty acid in his sperm plasma membranes. © 2010 Blackwell Verlag GmbH.

Supercritical fluid extraction (SFE) of liquid oleoresins (Capsicum annuum L. and Capsicum frutescens L.) was carried out in order to improve properties of oleoresins obtained by traditional processes using organic solvents. SFE allowed us to fractionate the different compounds present in oleoresins recovering both, an extract and a raffinate which can fulfill trader's needs. The aim of this work was to study the effect of pressure (140–300 bar) and temperature (313–333 K) affecting the yield and the commercial value of oleoresins extracts and raffinates, expressed in terms of parameters such as colour (SCU), pungency (SHU) and carotenoids and capsaicinoids concentration. A set of previous experiments was carried out to select the most suitable type of oleoresin and the initial ratio CO2/oleoresin which assures initial conditions in the biphasic area of CO2/oleoresin diagram to produce fractionation. A response surface methodology (RSM) was used to evaluate the effect of the factors over the variables and different linear correlations were proposed and validated to describe the responses studied. 300 bar and 333 K were selected as the best operational conditions to obtain fractionation. Finally, solubility parameters were obtained and correlated with semi-empirical models in order to obtain correlations which will be useful in subsequent stages of scaling-up.

The double addition of bis(trimethylsilyl) ketene acetals [R1, R2 = CH3, –(CH2)5–] to pyridine N-oxide promoted by triflic anhydride under mild conditions generates N-[(trifluoromethane)sulfonyl-1,2-dihydropyridine-2,4-dicarboxylic acids 2a–b. Subsequent reaction of these acids upon iodolactonization conditions affords tetrahydrofuro[3,2-b]pyridine-2(3H)-ones 3a–b containing an exo-insaturation on the products as a result of an unexpected decarboxylation.

In an attempt to evaluate the protective effect of a lipid-soluble antioxidant (butylated hydroxytoluene; BHT), semen from four dogs (Canis familiaris) was frozen in two different extenders (Uppsala or INRA-96 plus glycerol) with or without 1 mM BHT. Sperm membrane integrity using flow cytometry and motility using a computerized system were evaluated in each experimental group. The Uppsala extender was superior in all aspects of sperm function. The percentage of sperm membranes was significantly higher in semen samples frozen in presence of BHT. Our results suggest that the Uppsala extender can be improved with the addition of BHT.

Oxidative demetalation of Fischer ferrocenyl ethoxy carbene complexes ( 1a – c , M = Cr, Mo, W) and new Fischer ferrocenyl R-amino carbene complexes [ 2 – 5 ( a – c ), 11 – 15 ( a – c ), and 21 – 22 ( a – c ); M = Cr, Mo, W; R = H, CH 3 , C 2 H 5 , C 3 H 7 , (CH 2 ) 2 OH, (CH 2 ) 3 OH, (CH 2 ) 2 (OMe) 2 , (CH 2 ) 3 N(Me) 2 , CH 2 CH CH 2 , (CH 2 ) 2 OSi(CH 3 ) 3 , (CH 2 ) 3 OSi(CH 3 ) 3 ] with elemental sulfur–NaBH 4 were carried out under mild conditions, obtaining O -ethyl ferrocenecarbothioate ( 6 ) and novel ferrocenyl thioamides ( 7 – 10 and 16 – 20 ) in excellent yields.

Electrolytic chromium-coated steel plates with a polyethylene teraphthalate (PET) polymer coating, used in the manufacturing of both flat and rippled wall cans and containers, were submitted to 40, 60, and 80°C heating in an acetic-acetate medium and to electrochemical polarization tests, to study the PET coating degradation and the structural changes leading to a loss of the protection capacity of the steel, as well as to determine the detachment at the interface level. The samples were analyzed by Raman vibrational spectroscopy, micro-Raman, and attenuated total reflection to evaluate changes in the composition and structure of the coatings. Also, the PET surface was characterized by scanning electron microscopy (SEM) to establish the coating degradation. Spectroscopy analyses showed small changes of crystallinity in the PET thickness at 80°C and a reduced effect of the mechanical forming of plates on crystallinity. The SEM characterization evidenced the presence of surface defects and failures on the coating caused by the acetic-acetate medium. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The present study analysed the behaviour of titanium dioxide (TiO2) in polyethylene teraphthalate (PET) polymer coatings on electrolytic chromium-coated steel (ECCS) plates employed in the manufacturing of food containers. Also, the thermal source affecting rutile distribution in PET coatings was determined; i.e. whether it originated in the manufacturing processes and treatments of the composite to allow coextrusion and PET adherence on steel, or was rather a consequence of industrial canning processes. Measurements at parallel intervals from the surface to the metal interface were made by Raman and microRaman vibrational spectroscopy techniques to characterise the rutile distribution in the PET thickness. Finally, scanning and transmission electron microscopy observations determined the changes on the surface properties of the coating and provided information on the chemical and structural changes undergone by the polymer protective coating, which affect the performance and the protective capaci...

This work describes the carbonylation of hex-1-ene, cyclohexene, 2,3-dimethyl-but-1-ene and 2-methyl-pent-2-ene, their quaternary mixture and a real Venezuelan naphtha, catalyzed by a rhodium(I) [Rh(cod)(4-picoline)2](PF6) (cod = 1,5-cyclooctadiene) complex immobilized on poly(4-vinylpiridine) (P(4-VP)) in contact with methanol under carbon monoxide atmosphere. The conversion (%) of olefins to carbonylated products for the individual olefins decreases in the order: hex-1-ene (63) > cyclohexene (58) > 2,3-dimethyl-but-1-ene (50) > 2-methyl-pent-2-ene (31), under the following conditions: 0.5 g of P(4-VP) for [Rh] = 2 wt.% (1 × 10−4 mol), 10 mL of CH3OH, [olefin] = 1 × 10−2 mol, S/C = 100, P(CO) = 33 atm at 110 °C for 24 h. Other products such as H2 and CO2 coming from the catalysis of the water–gas shift reaction are observed. In this work, the carbonylation of hex-1-ene, cyclohexene, 2,3-dimethyl-but-1-ene and 2-methyl-pent-2-ene, their quaternary mixture and a real Venezuelan naphtha, catalyzed by a rhodium(I) [Rh(cod)(4-picoline)2](PF6) (cod = 1,5-cyclooctadiene) complex immobilized on poly(4-vinylpiridine) (P(4-VP)) in contact with methanol under carbon monoxide atmosphere is described.

In aqueous solution of tetrabutylammonium hydrogensulfate (N(C4H9)4HSO4), rhodium complexes like cis-[Rh(CO)2(amine)2](PF6) (amine = pyridine, 4-picoline, 3-picoline, 2-picoline, 3,5-lutidine or 2,6-lutidine) promote the carbonylation of 1-hexene to heptanoic acid and heptanal under carbon monoxide atmosphere. Gaseous by-products (H2 and CO2) from the catalysis of the water–gas shift reaction (WGSR) are also observed. The catalytic activities for heptanoic acid and heptanal production depend on the nature of the coordinate amine to the rhodium center for [Rh] = 1 × 10−4 mol, [1-hexene] = 0.05 mol, 40 mL of water (2.2 mol); 2.4 g of N(C4H9)4HSO4 (5.6 wt.%), S/C = 500, P(CO) = 22 atm at 150 °C. Analyses of kinetic results for the Rh/4-picoline system (one of the more active and the most stable catalyst among tested) towards the carbonylation reaction for the organic products formation show a nonlinear dependence on total rhodium concentration and on N(C4H9)4HSO4 amount in the range of studies. The last result suggested that the salty medium stabilize the ionic Rh catalytic species formed under the reaction conditions, therefore enhancing the reactivity. The increase in P(CO) is accompanied by improvement in the catalytic activities of oxygenated products, then reaches a maximum and starts decreasing at higher P(CO). These data are discussed in terms of catalytic cycles bearing a common Rh–H catalytic species.

Nitric oxide (NO) is a highly reactive free radical that plays a key role in intra- and intercellular signaling. Production of radical oxygen species and an apoptotic-like phenomenon have recently been implicated in cryodamage during sperm cryopreservation. The objective of the present study was to evaluate the effect of sodium nitroprusside (SNP), an NO donor, on boar sperm viability. Semen samples were pooled from four boars that were routinely used for artificial insemination. Flow cytometry was used to compare semen incubated with SNP to control semen. Specifically, NO production was measured using the NO indicator dye diaminofluorescein diacetate, and caspase activity was determined using the permeable pan-caspase inhibitor Z-VAD linked to FITC. SNP induced a significant increase in the percentage of sperm cells showing caspase activity, from 9.3% in control samples to 76.2% in SNP-incubated samples (P < 0.01). This study suggests that NO is a major free radical involved in boar sperm damage.

The reaction of bis(trimethylsilyl)ketene acetals 2 with N-heterocycles containing either one or two nitrogen atoms in the presence of triflic anhydride has been examined and the structures of the resulting products compared with those obtained by using methyl chloroformate as the activating agent. Whereas pyridine, pyrazine, quinoxaline and pyrimidine led to the same type of fused δ- or γ-lactones 4, 6, 8, 10 and 11 as with methyl chloroformate, the behaviour of pyridazine appeared to be peculiar. In the presence of methyl chloroformate, this heterocycle led to δ-lactones 16 via stable dihydropyridazines, with triflic anhydride, the direct formation of γ-lactones 20 was observed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Rhodium(I) complexes, cis-[Rh(CO)2(amine)2](PF6) (amine = 4-picoline, 3-picoline, 2-picoline, pyridine, 3,5-lutidine or 2,6-lutidine) dissolved in an aqueous solution of tetrabutylammonium hydrogensulfate (N(C4H9)4HSO4), catalyze the water-gas shift reaction (WGSR). The role of the coordinated amine on the catalytic activity was examined.

The synthesis, characterization, and catalytic properties of the zero-valent, group six metal complex formed by the reaction of [Mo(CO)3(CH3CN)3] and poly(4-vinylpyridine) (P(4-VP)) is described in this work. The pyridyl groups of the organic polymer are covalently bonded to the Mo centers as suggested by X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) techniques. The polymer-immobilized metal catalyst was also characterized by DTA–TGA, differential scanning calorimetry (DSC) analysis and its morphology and elemental analyses were studied by scanning electron microscopy/energy dispersive X-ray (SEM/EDX) techniques. In the presence of 2-ethoxyethanol the solid is an active catalyst for the heterogeneous hydrogenation of styrene to ethyl benzene.

A metal Fischer carbene [(CO) 5 W C(φ)OCH 2 CH 3 ] was covalently linked for the first time to the silanol groups of the mesoporous channels of SBA15 by following two different synthetic anchoring routes. The first one goes through the reaction of the SBA15 mesoporous silica walls functionalized by aminopropyltriethoxysilane (APTES) with a tungsten carbene Wφ, while in the second approach a precursor synthesized by reacting APTES with the carbene Wφ is then anchored via a direct bond to the silanol groups in the interior pore channels of SBA-15. This tethering is helpful to prevent the decomposition of the metallic complex. XRD, N 2 adsorption–desorption, and TEM analysis provide strong evidence that the mesoporous support structure retains its long-range ordering after the grafting process, despite a significant reduction of its specific surface area, pore-volume and pore-size. The chemical bonding of the tungsten carbene to the silanol groups of SBA-15 materials was studied with solid-state NMR spectroscopy. Both 13 C MAS NMR and 29 Si CP MAS NMR spectra confirm the covalent linking of the carbene to the silica-pore system.

The synthesis of ordered mesoporous silicas has received extensive attention due to their ordered arrangement, large surface area, and chemical stability. The pore size and pore volume of these materials make them suitable potential matrices for hosting. Here, we show that the covalent grafting of the Fischer carbene complex of tungsten [(CO) 5 W C(ph)OCH 2 CH 3 ] onto the silanol groups in inner walls of ordered mesoporous MCM-41 silica has been successfully accomplished. The introduction of the carbene complex is made by following two distinct anchoring procedures. The first one goes through the reaction of a mesoporous silica functionalized with 3-aminopropyltriethoxy silane (APTES) and a tungsten carbene, while in the second approach a precursor previously synthesized by reacting APTES with the tungsten carbene is then anchored via a direct bond with the silanol groups of the interior mesoporous pore channels of silica. XRD, N 2 adsorption/desorption, and TEM analysis provide strong evidence that the mesoporous support structure retains its long range ordering after the grafting process, despite a significant reduction of its specific surface area, pore volume and pore size. The chemical bonding of the tungsten carbene complex on the pore channels is also clearly confirmed by means of FTIR and solid-state NMR spectroscopy.

Soluble non-starch polysaccharides (NSP) present in cereal grains may affect performance of Nile tilapia through changes in digesta characteristics. The objective of this study was to investigate whether dietary cereal grains of increasing viscosity induce changes in digesta viscosity, dry matter and volatile fatty acids (VFA) and if these changes explain differences in nutrient digestibility and mineral absorption. Four experimental diets were formulated by adding 40% grains to a basal diet to obtain a range of dietary viscosities, increasing in the order of maize, barley, wheat and rye. The diets were assigned to 16 tanks with 40 fish (mean weight 70 g) each. Digesta viscosity increased with increasing grain viscosity (P

Catalytic activity for reduction of nitrobenzene to aniline (98%) and azobenzene (2%) using a poly(4-vinylpyridine)-immobilized Cu catalyst [Cu(II)/P(4-VP)] under a CO atmosphere in aqueous 2-ethoxyethanol was studied as a function of the various reaction parameters ([Cu], P(CO), T, and nitrobenzene/Cu molar ratio). Reaction rates were first-order in [Cu]tot over 1.0–12.0 wt.% range and in P(CO) over the 6.8–27.2 atm range. The catalytic activity proved to be non-linear in nitrobenzene/Cu ratio over 41–500 molar ratio range. These results suggest that the rate-limiting step is preceded by reversible coordination of nitrobenzene to a carbonyl–Cu(I) immobilized species. A catalytic mechanism consistent with the data is proposed.

The complex, [Rh(COD)(4-picoline)2](PF6) (COD = 1,5-cyclooctadiene), immobilized on poly(4-vinylpyridine) in contact with methanol catalyzes the hydroesterification and hydroformylation-acetalization of 1-hexene to methylheptanoate, heptanal and 1,1-dimethoxyheptane, respectively. The by-product, 1,1-dimethoxyheptane comes from the nucleophilic addition of methanol over the heptanal formed. Also, H2 and CO2 from the water gas shift reaction (WGSR) are observed. The catalytic activity for the hydroformylation and the WGSR proved to be non-linear in the rhodium total concentration range 0.9-5.0 wt.%.

The hydrodechlorination of chlorobenzene to benzene and biphenyl was studied using poly(4-vinylpyridine)-immobilized Cu catalysts under CO in basic (NaOH, N(C 2 H 5 ) 3 or Na(CH 3 CO 2 )) aqueous 2-ethoxyethanol medium. This Cu system also catalyzed the water gas shift reaction. The catalytic activities for hydrodechlorination of chlorobenzene to benzene were studied as functions of the reaction parameters (nature of the base, reaction time, [Cu], P(CO), T, and S/C). Among the different base studied activity is maximum for NaOH. The rate of benzene formation displays a first-order dependence on [Cu] over the range 1.25 12.50 wt%. This observation was interpreted in terms of the presence of active species having the same nuclearity. The catalytic activity towards benzene formation proved to be first order dependence on P(CO) over the range 5-35 atm. The kinetics behavior with respect to P(CO) leads to the proposal that CO addition to the catalytic species precedes the rate-limiting step. The catalytic activity proved to be non-linear in chlorobenzene/Cu content, over the range 50-400 molar ratio. The results suggest that the rate-limiting step is preceded by reversible oxidative addition of chlorobenzene to Cu immobilized species.

This work describes the catalytic hydroesterification and hydroformylation of 1-hexene by [Rh(cod)(amine) 2 ](PF 6 ) complexes (cod = 1,5-cyclooctadiene; amine = pyridine, 2-picoline, 3-picoline, 4-picoline, 3,5-lutidine or 2,6-lutidine) immobilized on poly(4-vinylpyridine) in contact with methanol under carbon monoxide atmosphere. In the presence of these immobilized complexes, 1-hexene, CO and methanol give methyl-heptanoate and 1,1-dimethoxy-heptane as the main reaction products and minor amounts of heptanal. The acetal by-product comes from the nucleophilic addition reaction of the methanol with the formed heptanal. Other products, such as H 2 and CO 2 coming from the catalysis of the water–gas shift reaction are observed. The reaction products distribution depends on the nature of the coordinated amine to the rhodium center and the reaction parameters.

The rhodium(I) complexes, cis-[Rh(CO)2(amine)2](PF6) (amine = pyridine, 2-picoline, 3-picoline, 4-picoline, 3,5-lutidine or 2,6-lutidine) dissolved in methanol under carbon monoxide atmosphere are effective catalysts for the hydroesterification and hydroformylation–acetalization of 1-hexene. In the presence of these soluble complexes, 1-hexene, CO and methanol give methyl-heptanoate and 1,1-dimethoxy-heptane as major products, and minor amounts of heptanal. The acetal product comes from the nucleophilic addition reaction of the methanol with the formed heptanal. Gaseous by-products (H2 and CO2) from the catalysis of the water–gas shift reaction (WGSR) are also observed. The reaction products distribution depends on the nature of the coordinated amine to the rhodium center. The effects of the reaction variables such as CO pressure, temperature, catalyst concentration, 1-hexene/Rh molar ratio and reaction medium, were also examined. These data are discussed in terms of catalytic cycles, and it is concluded that common Rh–H catalytic species are involved.