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1.
AIDS Care ; 34(5): 663-669, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33779425

RESUMO

People living with HIV (PLWH) often have worse health outcomes compared to HIV-uninfected individuals. We characterized PLWH followed at a tertiary care clinic in Montreal who acquired COVID-19 and described their outcomes during the first wave of the pandemic. A retrospective chart review was performed for PLWH followed at the Chronic Viral Illness Service with a positive COVID-19 nasopharyngeal PCR or symptoms suggestive of COVID-19 between 1 March and 15 June 2020. Data on demographics, socioeconomic status, co-morbidities and severity of COVID-19 and outcomes were extracted. Of 1702 individuals, 32 (1.9%) had a positive COVID-19 test (n = 24) or symptoms suspicious for COVID-19 (n = 3). Median age was 52 years [IQR 40, 62]. Nearly all (97%) earned $34,999 Canadian dollars or less. Eleven (34%) individuals worked in long-term care (LTC) homes while 5 (6%) lived in LTC homes. Median CD4 count was 566 cells/mm3 [347, 726] and six had detectable plasma HIV viral loads. Median duration of HIV was 17 years [7, 22] and 30 individuals had been prescribed antiretroviral therapy. Five persons were asymptomatic. Of symptomatic persons, 21 (12%), 1 (4%) and 3 (12%) individuals had mild, moderate and severe disease, respectively. Three individuals died with COVID-19. In one case, the cause of death was due to COVID-19, whereas in the other two cases, the individuals died with positive COVID-19 test results but the immediate cause of death is unclear. PLWH who tested positive for COVID-19 had low socioeconomic status and had employment or living conditions that put them at high risk. PLWH may be disproportionately impacted by the social determinants of health which predispose them to COVID-19.


Assuntos
COVID-19 , Infecções por HIV , COVID-19/epidemiologia , Canadá , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Centros de Atenção Terciária
2.
Comb Chem High Throughput Screen ; 10(2): 135-47, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17305488

RESUMO

High-throughput approaches were applied to the discovery of more efficient catalysts for various applications in emissions control. The screening approach was based on a hierarchy of qualitative or semi-quantitative primary screens for discovery of hits and quantitative secondary screens for confirmation and scale-up of leads. In this work, primary screening was carried out by fast scanning mass spectrometry (SMS) for NO(x) abatement, low temperature CO oxidation, VOC removal, CO(x) methanation and the water gas shift (WGS) reaction.


Assuntos
Técnicas de Química Combinatória/métodos , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Poluição Ambiental/prevenção & controle , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Compostos Inorgânicos de Carbono/química , Catálise , Transição de Fase , Temperatura , Água/química
3.
Org Lett ; 5(14): 2485-7, 2003 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-12841761

RESUMO

[reaction: see text] The palladium/ligand-catalyzed activation of chlorobenzene provides a general, efficient, and functional group friendly method for the selective oxidation of alcohols to carbonyl compounds.

4.
J Org Chem ; 64(18): 6797-6803, 1999 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11674689

RESUMO

The phenyl backbone-derived P,O-ligands 1 and 2 were investigated for their utility as ligands in palladium/ligand-catalyzed Suzuki reactions. The 2-(2'-dicyclohexylphosphinophenyl)-2-methyl-1,3-dioxolane (ligand 1) in combination with Pd(dba)(2) affords an efficient catalyst for general Suzuki reactions of a wide variety of arylboronic acids and aryl chlorides, bromides, and iodides to afford the desired biaryl products in high isolated yields. Arylboronic acids and aryl chlorides containing electron-poor, electron-rich, and ortho substituents participate effectively. In contrast, the structurally related ligand 2-(2'-dicyclohexylphosphinophenyl)-1,3-dioxolane (ligand 2) was found to be less efficient under similar conditions. The reaction of ligand 1 with Pd(dba)(2) affords the complex LPd(dba) (14, L = 1). The NMR spectroscopic and X-ray crystallographic data of complex 14 establish that ligand 1 functions as a P,O-chelating ligand in complex 14. The reaction of ligand 2 (2 equiv) with Pd(dba)(2) and excess 4-(t)()Bu-C(6)H(4)Br or the ligand displacement reaction of {Pd[P(o-tolyl)(3)](4-(t)()Bu-C(6)H(4))(&mgr;-Br)}(2) with ligand 2 affords the bis-phosphine complex L(2)Pd(4-(t)()Bu-C(6)H(4))(Br) (13, L = 2). The NMR spectroscopic data of complex 13 establish that ligand 2 in complex 13 functions as a nonchelating ligand. Thus, the higher efficiency of ligand 1 over ligand 2 in Pd/L-catalyzed Suzuki arylation of aryl chlorides can be ascribed to the ability of ligand 1 to generate and stabilize mono-phosphine P,O-chelating Pd/L intermediates, which appear to be most suitable for Suzuki arylation reactions involving certain substrates and conditions.

5.
Angew Chem Int Ed Engl ; 37(23): 3272-3275, 1998 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-29711404

RESUMO

Active polymerization catalysts, novel resin-bound diimine complexes of nickel(II) and palladium(II) are obtained by combinatorial synthesis and combined in a catalyst library. By tagging with fluorescent markers, the catalysts can be coded. Therefore, after cleavage of the tag from the polymer-coated resin, HPLC can be used to determine the pathway along which the products were formed.

6.
Angew Chem Int Ed Engl ; 38(4): 483-488, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29711775

RESUMO

In less than one minute the catalytic activity and selectivity of a single catalyst was measured in combinatorial libraries of ternary Rh-Pd-Pt-Cu alloys. Only slightly more than two hours were needed to complete a library with 136 elements. The elements of the libraries (ca. 2-4 µg of material) are contained in a two-dimensional array synthesized by a thin-film technique. The analysis was performed by a scanning mass spectrometer (see picture).

8.
Comb Chem High Throughput Screen ; 13(4): 318-30, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20156149

RESUMO

State-of-art water gas shift catalysts (FeCr for high temperature shift and CuZn for low temperature shift) are not active enough to be used in fuel processors for the production of hydrogen from hydrocarbon fuels for fuel cells. The need for drastically lower catalyst volumes has triggered a search for novel WGS catalysts that are an order of magnitude more active than current systems. Novel catalytic materials for the high, medium and low temperature water gas shift reactions have been discovered by application of combinatorial methodologies. Catalyst libraries were synthesized on 4 inch wafers in 16 x 16 arrays and screened in a high throughput scanning mass spectrometer in the temperature range 200 degrees C to 400 degrees C. More than 200 wafers were screened under various conditions and more than 250,000 experiments were conducted to comprehensively examine catalyst performance for various binary, ternary and higher-order compositions.


Assuntos
Técnicas de Química Combinatória , Gases/química , Água/química , Catálise , Temperatura Alta , Espectrometria de Massas
9.
J Org Chem ; 69(25): 8626-33, 2004 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-15575738

RESUMO

The palladium/phosphine-catalyzed productive chloroarene C-Cl bond activation provides general, efficient, and functional group friendly methods for the selective oxidation of alcohols and the hydrodechlorination of chloroarenes.

10.
Chem Rec ; 2(4): 278-89, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12203910

RESUMO

The discovery of new olefin polymerization catalysts is currently a time-intensive trial-and-error process with no guarantee of success. A fully integrated high-throughput screening workflow for the discovery of new catalysts for polyolefin production has been implemented at Symyx Technologies. The workflow includes the design of the metal-ligand libraries using custom-made computer software, automated delivery of metal precursors and ligands into the reactors using a liquid-handling robot, and a rapid primary screen that serves to assess the potential of each metalligand-activator combination as an olefin polymerization catalyst. "Hits" from the primary screen are subjected to secondary screens using a 48-cell parallel polymerization reactor. Individual polymerization reactions are monitored in real time under conditions that provide meaningful information about the performance capabilities of each catalyst. Rapid polymer characterization techniques support the primary and secondary screens. We have discovered many new and interesting catalyst classes using this technology.

11.
J Am Chem Soc ; 125(14): 4306-17, 2003 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-12670253

RESUMO

For the first time, new catalysts for olefin polymerization have been discovered through the application of fully integrated high-throughput primary and secondary screening techniques supported by rapid polymer characterization methods. Microscale 1-octene primary screening polymerization experiments combining arrays of ligands with reactive metal complexes M(CH(2)Ph)(4) (M = Zr, Hf) and multiple activation conditions represent a new high-throughput technique for discovering novel group (IV) polymerization catalysts. The primary screening methods described here have been validated using a commercially relevant polyolefin catalyst, and implemented rapidly to discover the new amide-ether based hafnium catalyst [eta(2)-(N,O)[bond](2-MeO[bond]C(6)H(4))(2,4,6-Me(3)C(6)H(2))N]Hf(CH(2)Ph)(3) (1), which is capable of polymerizing 1-octene to high conversion. The molecular structure of 1 has been determined by X-ray diffraction. Larger scale secondary screening experiments performed on a focused 96-member amine-ether library demonstrated the versatile high temperature ethylene-1-octene copolymerization capabilities of this catalyst class, and led to significant performance improvements over the initial primary screening discovery. Conventional one gallon batch reactor copolymerizations performed using selected amide-ether hafnium compounds confirmed the performance features of this new catalyst class, serving to fully validate the experimental results from the high-throughput approaches described herein.

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