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1.
Appl Radiat Isot ; 192: 110578, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36473318

RESUMO

The associated particle (AP) technique has recently been used with a high-purity germanium γ-ray spectrometer to assess its capability to improve field identification of recovered chemical warfare (CW) materiel through prompt gamma-ray neutron activation analysis (PGNAA) measurements. A particularly challenging pair of CW agents commonly found in recovered munitions are phosgene (CG) and cyanogen chloride (CK), which have two of three elements in common, i.e. chlorine and carbon, but differ in the third being either oxygen or nitrogen. The detection of both latter elements is complicated by high oxygen concentration in the field environment which interferes with the small signal produced from the chemical agents. The matter is further complicated by the precautionary field practice of overpacking recovered munitions with vermiculite in larger steel multiple round containers (MRCs), which places additional oxygen-rich material in contact with the munition while further attenuating an already weak signal emitted from the munition center. This work reports quantitative results from realistic field measurements of CG and CK simulants in mock 4.2-inch (11 cm) mortar rounds overpacked with vermiculite in a large MRC. Results obtained with the AP technique are compared to those obtained with the traditional PGNAA approach for both overpacked- and bare-munition measurements. The AP technique is shown to provide a much more confident discrimination between the two chemicals, particularly for the more challenging field-relevant overpacked measurements, where a significant gain in sensitivity to all the key elements (chlorine, carbon, nitrogen and oxygen) is achieved.


Assuntos
Fosgênio , Cloro , Análise Espectral , Carbono , Nitrogênio/análise , Oxigênio , Nêutrons
2.
Dalton Trans ; 47(1): 83-95, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29226936

RESUMO

The coordination chemistry of intramolecular stannylene phosphorus Lewis pairs incorporated into four membered ring systems is presented. Previously reported coordination chemistry of stannylene and phosphorus towards palladium(0) is extended by using Pd(nbe)3 as a precursor, yielding co-ligand free complexes. An equilibrium of one or two stannylene phosphorus ligands coordinated to Pd(0) was observed with tin acting either as a donor or an acceptor towards palladium. Furthermore, the reactions with transition metal(i) chlorides, [(cod)IrCl]2, [(cod)RhCl]2 and Me2SAuCl are reported. They proceed via insertion of stannylene into the M-Cl bonds, yielding metal complexes with chelating stannide phosphorus ligands. For gold, a dinuclear complex with bridging P-Sn ligands was formed. Furthermore, the reaction of a P → Sn Lewis pair in a three membered ring system with (cod)PtMe2 is reported.

3.
Dalton Trans ; 45(19): 8081-8, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27077483

RESUMO

The reaction of intramolecular stannylene phosphorus Lewis pairs with heavier dichlorides of group 14 (GeCl2, SnCl2, PbCl2) is reported. Phosphine base stabilized stannyl germylenes/stannylenes were formed by the oxidative addition of an E-Cl bond to the stannylene tin atom (E = Ge, Sn). In solution, a dynamic equilibrium between two diastereomeric configurations was observed. With PbCl2 a redox reaction towards elemental lead and the dichlorinated tin(iv) compound was found. All compounds were characterized by X-ray diffraction, NMR spectroscopy and elemental analysis.

4.
Dalton Trans ; 45(14): 5933-6, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26515430

RESUMO

The reaction of a terphenyl tin(ii) compound bearing an η(3) coordinating allyl ligand with adamantyl phosphaalkyne is reported. The quantitative stochiometric reaction towards one product involves an addition of one Sn-Ar bond across the C[triple bond, length as m-dash]P triple bond and formation of a phosphadistannacyclobutene ring. This kinetically favoured product can be isolated in the solid state, however, in solution, it shows rearrangement towards a new tin-phosphorus molecule over a period of five days.

5.
Int J Artif Organs ; 27(2): 137-48, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15061475

RESUMO

PURPOSE: To compare long-term efficacy and biocompatibility of the 5 most commonly applied LDL-apheresis techniques using a specifically modified calculation method of the area under the curve (AUC) for laboratory parameters. DESIGN: Retrospective long-term analysis of 20 patients with homozygous or severe heterozygous familial hypercholesterolemia. PROCEDURES: The following 5 extra-corporeal LDL-apheresis methods were compared: IMAL (Immuno Adsorption of Lipoproteins), DSA (Dextran Sulphate Adsorption), HELP (Heparin Induced Extra-corporeal LDL Precipitation), DALI (Direct Adsorption of Lipoproteins), MDF (Membrane Differential Filtration). MAIN OUTCOME MEASURES: AUC derived plasma concentrations (C(AUC)) of lipoproteins between two apheresis procedures and their long-term course. Comparison of biocompatibility and efficacy concerning the LDL-C target of < 2.6 mmol/L of 5 apheresis techniques. Progression of atherosclerosis in patients with severe hypercholesterolemia. MAIN FINDINGS: The means of AUC derived average plasma concentrations (C(AUC)) of all treatment intervals were for LDL-C and the LDL/HDL ratio as follows: IMAL (5.59 mmol/L; ratio 4.1), DSA (3.03 mmol/L; ratio 2.0), HELP (4.06 mmol/L; ratio 2.2), DALI (3.83 mmol/L; ratio 3.3), MDF (3.26 mmol/L; ratio 3.2). Coronary heart disease and cardiac events (myocardial infarction, PTCA/ stent implantation, CABG) progressed in only 2 patients whereas atherosclerosis manifestations (sclerosis abdominal aorta, carotid artery stenosis, peripheral vascular disease) worsened in 13 patients. Mean ergometric capacity improved from 112 to 118 Watt. CONCLUSIONS: All 5 apheresis methods (IMAL, DSA, HELP, DALI, MDF) proved to be safe and suitable for long-term treatment in patients with severe hypercholesterolemia. The introduction of the C(AUC) revealed that the target of LDL-C < 2.6 mmol/L was not achieved with regard to the time averaged concentration (C(AUC)).


Assuntos
Remoção de Componentes Sanguíneos/métodos , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Doença da Artéria Coronariana/terapia , Hiperlipoproteinemia Tipo II/terapia , Adulto , Área Sob a Curva , HDL-Colesterol/análise , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Feminino , Seguimentos , Humanos , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Resultado do Tratamento
6.
Insect Mol Biol ; 12(1): 51-60, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12542635

RESUMO

Trafficking of cholesterol in insects is a very important process due to the fact that insects depend on dietary cholesterol to fulfil their physiological needs. We identified a putative mosquito sterol carrier protein-2 (SCP-2) cDNA from fourth instar subtracted cDNA library. The AeSCP-2 protein has high degree homology in the sterol transfer domain to both rat and human SCP-2. Transcripts of AeSCP-2 in fourth instars were detected strongly in the midgut, and weakly in the head and hindgut. In the early pupae, AeSCP-2 transcription was observed in the thorax, head and body wall of abdomen, but not in the gut. The interaction of mosquito sterol carrier protein-2 (AeSCP-2) with cholesterol was examined. The Kd of purified recombinant AeSCP-2 to cholesterol was 5.6 +/- 0.6 x 10-9 m using radiolabelled cholesterol-binding assay. The results suggest that AeSCP-2 has high affinity to cholesterol and may function as a carrier protein in mosquitoes.


Assuntos
Aedes/genética , Proteínas de Transporte/genética , Colesterol/metabolismo , Aedes/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Western Blotting , Proteínas de Transporte/metabolismo , DNA Complementar/química , DNA Complementar/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , RNA/química , RNA/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Alinhamento de Sequência
7.
Nurs Adm Q ; 25(3): 55-60, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18193590

RESUMO

Prayer and Spirituality are now recognized complementary therapies and receiving funding through the National Institutes of Health. More than 130 controlled studies demonstrate that prayer or a prayer-like state of compassion, empathy, and love can bring about measurable healthful changes. Nurses and all health care professionals are in perfect position to help optimize these benefits for their patients. This article suggests practical ways to support patients through challenging times.


Assuntos
Empatia , Enfermagem/métodos , Espiritualidade , Adaptação Psicológica , Humanos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Resultado do Tratamento
10.
J Air Waste Manag Assoc ; 48(10): 924-30, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9798432

RESUMO

Conversion varnishes are two-component, acid-catalyzed varnishes that are commonly used to finish cabinets. They are valued for their water and stain resistance, as well as their appearance. They have been found, however, to contribute to indoor emissions of organic compounds. For this project, three commercially available conversion varnish systems were selected. A U.S. Environmental Protection Agency (EPA) Method 24 analysis was performed to determine total volatile content, and a sodium sulfite titration method was used to determine uncombined (free) formaldehyde content of the varnish components. The resin component was also analyzed by gas chromatography/mass spectroscopy (GC/MS) (EPA Method 311 with an MS detector) to identify individual organic compounds. Dynamic small chamber tests were then performed to identify and quantify emissions following application to coupons of typical kitchen cabinet wood substrates, during both curing and aging. Because conversion varnishes cure by chemical reaction, the compounds emitted during curing and aging are not necessarily the same as those in the formulation. Results of small chamber tests showed that the amount of formaldehyde emitted from these coatings was 2.3-8.1 times the amount of free formaldehyde applied in the coatings. A long-term test showed a formaldehyde emission rate of 0.17 mg/m2/hr after 115 days.


Assuntos
Poluentes Ocupacionais do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Pintura/análise , Formaldeído/análise
13.
Psychopharmacology (Berl) ; 113(3-4): 429-37, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7862855

RESUMO

Like hallucinogenic 5-HT2 agonists, LSD (d-lysergic acid diethylamide) produces characteristic decreases in locomotor activity and investigatory behaviors of rats tested in a novel environment. Because LSD is an agonist at both 5-HT1A and 5-HT2 receptors, however, the respective influences of these different receptors in the behavioral effects of LSD remain unclear. In particular, the paucity of selective 5-HT1A antagonists has made it difficult to assess the specific contribution of 5-HT1A receptors to the effects of LSD. An alternative approach to the delineation of receptor-specific effects is the use of cross-tolerance regimens. In the present studies, rats were pretreated with saline, 8-hydroxy-2(di-n-propylamino)-tetralin (8-OH-DPAT) (0.5 mg/kg SC), 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (1.0 mg/kg SC), or LSD (60 micrograms/kg SC), every 12 h for 5 or 8 days. Thirty-six hours later, rats were tested in a behavioral pattern monitor 10 min after injection of saline, 0.5 mg/kg 8-OH-DPAT, 1.0 mg/kg DOI, or 60 micrograms/kg LSD. As expected, tolerance to the decreases in locomotor activity produced by acute administrations of 8-OH-DPAT, DOI, or LSD occurred when rats were pretreated chronically with 8-OH-DPAT, DOI, or LSD, respectively. Furthermore, pretreatment with either 8-OH-DPAT or DOI produced cross-tolerance to LSD. These results support the hypothesis that the effects of LSD in this model reflect a combination of 5-HT1A and 5-HT2 effects and support the view that there is an interaction between 5-HT1A and 5-HT2 receptors.


Assuntos
Comportamento Animal/efeitos dos fármacos , Dietilamida do Ácido Lisérgico/farmacologia , Receptores de Serotonina/efeitos dos fármacos , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Anfetaminas/farmacologia , Animais , Relação Dose-Resposta a Droga , Tolerância a Medicamentos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor de Serotonina/farmacologia
14.
Psychopharmacology (Berl) ; 113(2): 284-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7855195

RESUMO

Several reports have speculated that the tryptamine-derived drug alpha-ethyltryptamine (AET) may have effects similar to those of the amphetamine-derived drug 3,4-methylenedioxymethamphetamine (MDMA). Indeed, the US Drug Enforcement Administration has recently placed AET on the Schedule I list because of its putative similarity to MDMA. The Behavioral Pattern Monitor, which quantifies locomotor and investigatory responses of rats, was used to characterize the effects of AET in a paradigm that distinguishes between the effects of traditional hallucinogens, amphetamine-like stimulants, and MDMA-like drugs. First, a dose-response study revealed that all doses of AET tested (5, 10, 20 mg/kg) significantly increased locomotor activity. Locomotor hyperactivity is produced by MDMA or amphetamine-like stimulants, but not by classical hallucinogens, such as LSD or mescaline. Additionally, AET significantly decreased measures of investigatory behavior. Similar decreases occur with MDMA or hallucinogen administration. Second, as with MDMA, the locomotor hyperactivity induced by AET was attenuated by pretreatment (10 mg/kg) with the serotonin reuptake inhibitor fluoxetine. Thus, AET, a tryptamine-derived drug, appears to produce an MDMA-like profile of behavioral changes by virtue of releasing presynaptic serotonin.


Assuntos
Comportamento Animal/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Triptaminas/farmacologia , Animais , Comportamento Exploratório/efeitos dos fármacos , Fluoxetina/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/antagonistas & inibidores , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética , Ratos , Ratos Sprague-Dawley , Receptores Pré-Sinápticos/efeitos dos fármacos , Receptores Pré-Sinápticos/metabolismo , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Triptaminas/antagonistas & inibidores , Triptaminas/farmacocinética
15.
Andrologia ; 23(1): 41-3, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1897754

RESUMO

In 13 healthy women and 6 virgins the cellular sensitization against sperm and seminal plasma antigens was demonstrated by an indirect lymphokin assay, the leucocyte migration inhibition test (LMI-test) using the following preparations: "washed" spermatozoa, seminal plasma and spermatozoa of the supernatant prepared with the "swim-up" technique. In both groups of women a cellular sensitization against sperm and seminal plasma antigens could be observed. Further, a dose dependent correlation was found in that way, that increasing concentrations of spermatozoa lead to an increased inhibition of macrophage migration. In virgins cellular sensitization against seminal plasma proteins did not differ from non-virgins, only the percentage of significant reactions in the LMI-Test was reduced. As low sperm concentrations (1 million ml-1), which represent best the physiological situation in the uterus, induced an enhanced migrations of macrophages the enhancement of macrophage migration is considered as physiological cellular sensitization of females against sperm-associated antigens.


Assuntos
Antígenos/imunologia , Imunização , Sêmen/imunologia , Espermatozoides/imunologia , Adulto , Inibição de Migração Celular , Feminino , Humanos , Imunidade Celular , Macrófagos/imunologia , Masculino
17.
Home Healthc Nurse ; 8(3): 13-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2376516

RESUMO

Since the implementation of HCFA forms 484, 486, and 487, the home health industry has experienced a dramatic increase in the rate of reimbursement denials. One agency responded by developing a utilization review program that has successfully reduced technical and medical denials.


Assuntos
Reembolso de Seguro de Saúde , Revisão da Utilização de Recursos de Saúde/tendências , Serviços de Assistência Domiciliar , Humanos , Enfermeiras e Enfermeiros , Estados Unidos
18.
Biochim Biophys Acta ; 1004(3): 300-8, 1989 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-2503030

RESUMO

The monolayer system was employed to investigate the relative affinities of apolipoproteins A-I and A-II for the lipid/water interface. The adsorption of reductively 14C-methylated apolipoproteins to phospholipid monolayers spread at the air/water interface was determined by monitoring the surface pressure of the mixed monolayer and the surface concentration of the apoprotein. ApoA-II has a higher affinity than apoA-I for lipid monolayers; for a given initial surface pressure, apoA-II adsorbs more than apoA-I to monolayers of egg phosphatidylcholine (PC), distearoyl-PC and human high-density lipoprotein (HDL3) surface lipids. Comparison of the molecular packing of apolipoproteins A-I and A-II suggests that apoA-II adopts a more condensed conformation at the lipid/water interface compared to apoA-I. The ability of apoA-II to displace apoA-I from egg PC and HDL3 surface lipid monolayers was studied by following the adsorption and desorption of the reductively 14C-methylated apolipoproteins. At saturating subphase concentrations of the apoproteins (3.10(-5) g/100 ml), two molecules of apoA-II absorbed for each molecule of apoA-I displaced. This displacement was accompanied by an increase in surface pressure. An identical stoichiometry for the displacement of apoA-I from HDL particles by apoA-II has been reported by others. At low subphase concentrations of apoproteins (5.10(-6) g/100 ml), the apoA-I/lipid monolayer was not fully compressed and could accommodate the adsorbing apoA-II molecules without displacement of apoA-I molecules. ApoA-I molecules were unable to displace apoA-II from the lipid/water interface. The average residue hydrophobicity of apoA-II is higher than that of apoA-I; this may contribute to the higher affinity of apoA-II for lipids compared to apoA-I. The probable helical regions in apolipoproteins A-I and A-II were located using a secondary structure prediction algorithm. The analysis suggests that the amphiphilic properties of the alpha-helical regions of apoA-I and apoA-II are probably not significantly different. Further understanding of the differences in surface activity of these apolipoproteins will require more knowledge of their secondary and tertiary structures.


Assuntos
Apolipoproteínas A/metabolismo , Sequência de Aminoácidos , Apolipoproteína A-I , Apolipoproteína A-II , Fenômenos Químicos , Química , Humanos , Metabolismo dos Lipídeos , Dados de Sequência Molecular , Conformação Proteica , Propriedades de Superfície , Água/metabolismo
19.
Brain Res Bull ; 21(4): 607-16, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3208148

RESUMO

We demonstrate that the brain spectrin isoforms (240/235) and (240/235E) are present in all mammalian species studied (human, bovine, mouse, and rat). Immunohistochemistry with a panel of eleven polyclonal antibodies have indicated an identical localization of the brain spectrin isoforms in all mammalian species. Brain spectrin(240/235) is found primarily in axons, and brain spectrin(240/235E) primarily in cell bodies and dendrites. Immunoprecipitation and Western blotting studies have indicated that the subunit molecular weights of brain spectrin(240/235) and (240/235E) are identical in all mammalian species. We demonstrate that when proteolysis is not completely blocked during immunoprecipitation studies, the 235 kDa subunits are converted to a 230 kDa polypeptide [brain spectrin(240/235)] and a 232 kDa polypeptide [brain spectrin(240/235E)]. Finally, we show that both the alpha and beta subunits of brain spectrin(240/235) and brain spectrin(240/235E) are antigenically distinct in every species examined. These studies indicate that previous findings on the structure, location, and function of mouse brain spectrin isoforms can now be generalized to all mammalian species.


Assuntos
Encéfalo/metabolismo , Espectrina/metabolismo , Idoso , Animais , Especificidade de Anticorpos , Bovinos , Humanos , Imuno-Histoquímica , Isomerismo , Masculino , Camundongos , Ratos
20.
Biochim Biophys Acta ; 959(3): 229-37, 1988 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-3128334

RESUMO

Surface pressure (pi) and adsorption isotherms for human apolipoproteins A-I and A-II at the air/water interface have been determined and used to deduce the probable molecular structures of the monomolecular films. The surface concentrations were measured using the surface radioactivity method to monitor the adsorption of reductively [14C]methylated apoproteins. Apolipoprotein A-I and apolipoprotein A-II are extremely surface-active proteins and adsorb to exert maximal pi values of 22 and 24 mN.m-1 respectively, at a steady-state subphase concentration of about 3.10(-5) g/100 ml (equivalent to 11 and 17 nM for apolipoprotein A-I and apolipoprotein A-II, respectively). At saturation monolayer coverage, the average molecular areas for apolipoprotein A-I and apolipoprotein A-II are 15 and 13 A2/residue, respectively. These packing densities are consistent with monolayers consisting largely of alpha-helical protein molecules lying with the long axes of the helical segments in the plane of the interface. Comparison of the molecular packings of spread and adsorbed monolayers of these proteins indicates that at low pi values, the adsorbed films are more expanded, but at high pi values, the molecular packing in both types of film is the same.


Assuntos
Apolipoproteínas A , Adsorção , Apolipoproteína A-I , Apolipoproteína A-II , Fenômenos Químicos , Físico-Química , Humanos , Propriedades de Superfície
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