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1.
South. Afr. j. anaesth. analg. (Online) ; 29(4): 128-134, 2023. tables, figures
Artigo em Inglês | AIM (África) | ID: biblio-1511909

RESUMO

Preoperative anxiety potentially results in perioperative anaesthetic complications. This study aimed to determine the prevalence of preoperative anxiety in adult patients scheduled to undergo elective orthopaedic surgery at an academic hospital in South Africa and identify contributory factors. Methods: This cross-sectional study included all patients scheduled for elective orthopaedic surgery the following day from 25 July to 3 November 2021. An adapted version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS) was used. Four questions determined the patients' anxiety and two questions their desire for more information about their forthcoming anaesthesia and surgery. A 5-point Likert scale was used to capture the patients' responses to the APAIS questions. Data on other possible contributory factors to preoperative anxiety were collected using a questionnaire. Results: Of the 88 patients, 82 (93.2%) were included in the study. A total of 40 (48.8%) patients had an APAIS score of ≥ 11, indicating anxiety. A high need-for-information score (≥ 8) was found in 31 (37.8%) patients. A significant association between patients with a higher anxiety score and a higher need-for-information score (p = 0.0063) was identified. Other non-significant factors associated with a higher anxiety score included a lower level of education and no postoperative home support. Conclusion: Patients with a high need for information tended to be more anxious on the day before surgery. The APAIS could be introduced in preoperative ward admissions to identify these patients and provide an appropriate level of counselling about their planned procedure. Counselling might reduce their preoperative anxiety, but further research needs to confirm this assertion. Larger studies are recommended to determine the influence of other factors contributing to preoperative anxiety


Assuntos
Humanos , Cirurgia Geral , Cuidados Pré-Operatórios , Adulto , Pacientes , Enfermagem Perioperatória , Estudos Transversais , Complicações Intraoperatórias
2.
J Cosmet Sci ; 60(6): 617-26, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20038350

RESUMO

The aim of this study was to investigate the effect of iron oxide application on improving the volume of eyelashes. Iron oxide, having a negative surface charge in its natural form, was coated with commercial cationic polymers to increase its adhesion. The iron oxides coated with different types and concentrations of these polymers were incorporated into a basic mascara formula to test their volume effects by means of the weight difference of eyelashes.The results indicated that the type and concentration of coating materials affect the surface zeta potential and particle cluster size of iron oxides. The type of cationic polymer, especially, was shown to modify both factors of iron oxide. The obtained results also suggested that the volume effect of mascara increases with a higher positive surface zeta potential and a smaller particle cluster size of the coated iron oxides.


Assuntos
Celulose/análogos & derivados , Cosméticos/química , Pestanas/química , Compostos Férricos/química , Compostos de Amônio Quaternário/farmacologia , Adulto , Celulose/farmacologia , Pestanas/efeitos dos fármacos , Feminino , Humanos , Propriedades de Superfície
3.
Biophys Chem ; 92(1-2): 35-45, 2001 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-11527577

RESUMO

The binding mode of porphyrins, namely meso-tetrakis(N-methyl pyridinium-4-yl)porphyrin (H(2)TMPyP), was classified in this work by absorption and circular dichroism(CD) spectroscopy. The three binding modes of intercalation, minor groove binding and external stacking exhibit their own characteristic absorption and CD spectra. Intercalation occurs for this porphyrin when bound to GC-rich polynucleotides at a low mixing ratio, as expected. This binding mode produces hypochromism and a red shift in the absorption band and a negative CD band in the Soret absorption region. When it is complexed with AT-rich polynucleotides at a low mixing ratio, hypochromism and a red shift in the absorption band and a positive CD peak is apparent, and this species can easily be assigned to the minor groove-binding mode. For both AT- and GC-rich polynucleotides at a high binding ratio, an excitonic CD was apparent. The sign of excitonic CD depends on the order of the DNA bases; the CD spectra of H(2)TMPyP complexed with non-alternating homopolymer (disregarding the nature of base pairs, i.e. AT or GC) are characterized by a positive band at short wavelengths followed by a negative band at long wavelengths. In contrast, those complexed with alternating polynucleotide were opposite to those of non-alternating homopolymers.


Assuntos
Polinucleotídeos/química , Porfirinas/química , Fenômenos Químicos , Físico-Química , Dicroísmo Circular , DNA/química , Poli dA-dT/química , Polinucleotídeos/síntese química , Espectrofotometria Ultravioleta
4.
Biochim Biophys Acta ; 1517(2): 220-7, 2001 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-11342102

RESUMO

Optical spectroscopic properties of 4',6-diamidino-2-phenylindole (DAPI) and ethidium bromide complexed with poly(dG).poly(dC).poly(dC)(+) triplex and poly(dG).poly(dC) duplex were compared in this study. When complexed with both duplex and triplex, ethidium is characterized by hypochromism and a red shift in the absorption spectrum, a complicate induced circular dichroism (CD) band in the polynucleotide absorption region, and a negative reduced linear dichroism signal in both polynucleotide and drug absorption regions. The spectral properties for both duplex- and triplex-bound ethidium are identical and both can be understood by the intercalation binding mode. In contrast, the absorption and CD spectra of DAPI complexed with triplex differ from those of the DAPI-duplex complex, although both complexes can be understood by the intercalation binding mode. Considering that the third strand runs along the major groove of the template duplex, we conclude that the DAPI molecule partially intercalates near the major groove of the duplex, where the third strand can affect its spectroscopic properties.


Assuntos
Etídio/química , Indóis/química , Substâncias Intercalantes/química , Polidesoxirribonucleotídeos/química , Dicroísmo Circular , Conformação Molecular , Estrutura Molecular , Espectrofotometria
5.
Inorg Chem ; 40(9): 2105-10, 2001 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11304156

RESUMO

Infinite molecular helices [Ag(3,3'-Py2S)]X (3,3'-Py2S = 3,3'-thiobispyridine; X- = BF4-, ClO4-, and PF6-) have been rationally constructed or induced. Crystallographic characterization (X- = BF-, monoclinic P2(1)/n, a = 8.946(3) A, b = 14.130(2) A, c = 10.124(2) A, beta = 107.83(2) degrees, V = 1218.3(5) A3, Z = 4, R = 0.0351; X- = ClO4-, monoclinic P2(1)/n, a = 8.884(1) A, b = 14.305(3) A, c = 10.110(1) A, beta = 106.78(1) degrees, V = 1230.1(3) A3, Z = 4, R = 0.0417; X- = PF6-, monoclinic P2(1)/c, a = 10.959(2) A, b = 9.808(2) A, c = 14.065(3) A, beta = 112.03(2) degrees, V = 1401.4(5) A3, Z = 4, R = 0.0442) reveals that the skeletal structure is an oblong cylindrical cationic helix consisting of alternating Ag(I) and 3,3'-Py2S species and that its counteranions are pinched in two columns inside each helix. The formation of the helical coordination polymer appears to be primarily associated with a suitable combination of the skewed conformer of 3,3'-Py2S and the potential linear geometry of the N-Ag(I)-N bond. However, the framework of the nitrate analogue [Ag(3,3'-Py2S)NO3] (monoclinic P2(1)/c, a = 8.177(2) A, b = 10.291(1) A, c = 14.771(2) A, beta = 102.19(1) degrees, V = 1214.9(4) A3, Z = 4, R = 0.0300) is a two-dimensional network consisting of an 18-membered ring unit, where each 3,3'-Py2S acts as a N,N',S- tridentate ligand connecting three tetrahedral silver(I) ions with the monodentate nitrate weakly bonded to the silver (Ag.O = 2.65(1) A) rather than acting as a counteranion. The anion exchange of [Ag(3,3'-Py2S)NO3] with BF4-, ClO4-, or PF6- has been accomplished in aqueous media. The two-dimensional networks are easily converted into the helices via the anion exchange, but the reverse anion exchange proceeds slightly. Thermal analyses indicate a relationship between the thermal stabilities and the structural properties.


Assuntos
Piridinas/química , Compostos de Prata/química , Sulfetos/química , Ânions , Cristalografia por Raios X , Substâncias Macromoleculares , Estrutura Molecular , Termogravimetria
6.
J Inorg Biochem ; 80(3-4): 219-25, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11001092

RESUMO

An electron-rich iron(III) porphyrin complex (meso-tetramesitylporphinato)iron(III) chloride [Fe(TMP)Cl], was found to catalyze the epoxidation of olefins by aqueous 30% H2O2 when the reaction was carried out in the presence of 5-chloro-1-methylimidazole (5-Cl-1-Melm) in aprotic solvent. Epoxides were the predominant products with trace amounts of allylic oxidation products, indicating that Fenton-type oxidation reactions were not involved in the olefin epoxidation reactions. cis-Stilbene was stereospecifically oxidized to cis-stilbene oxide without giving isomerized trans-stilbene oxide product, demonstrating that neither hydroperoxy radical (HOO*) nor oxoiron(IV) porphyrin [(TMP)FeIV=O] was responsible for the olefin epoxidations. We also found that the reactivities of other iron(III) porphyrin complexes such as (meso-tetrakis(2,6-dichlorophenyl)porphinato)iron(III) chloride [Fe(TDCPP)Cl], (meso-tetrakis(2,6-difluorophenyl)porphinato)iron(III) chloride [Fe(TDFPP)Cl], and (meso-tetrakis(pentafluorophenyl)porphinato)iron(III) chloride [Fe(TPFPP)CI] were significantly affected by the presence of the imidazole in the epoxidation of olefins by H2O2. These iron porphyrin complexes did not yield cyclohexene oxide in the epoxidation of cyclohexene by H2O2 in the absence of 5-Cl-1-MeIm in aprotic solvent; however, addition of 5-Cl-1-MeIm to the reaction solutions gave high yields of cyclohexene oxide with the formation of trace amounts of allylic oxidation products. We proposed, on the basis of the results of mechanistic studies, that the role of the imidazole is to decelerate the O-O bond cleavage of an iron(III) hydroperoxide porphyrin (or H2O2-iron(II) porphyrin adduct) and that the intermediate transfers its oxygen to olefins prior to the O-O bond cleavage.


Assuntos
Alcenos/química , Compostos de Epóxi/química , Peróxido de Hidrogênio/química , Imidazóis/química , Metaloporfirinas/química , Catálise , Cicloexanos/química , Cicloexenos , Eletroquímica , Conformação Molecular , Estrutura Molecular
7.
Food Chem Toxicol ; 37(5): 509-13, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10456679

RESUMO

The effects of dietary oxidized fish oil and alpha-tocopherol on the thiobarbituric acid (TBA) values and phospholipid hydroperoxide levels of the erythrocyte membrane were studied in rats. No significant differences in the TBA values or phospholipid hydroperoxide levels of the membrane were observed between groups fed either oxidized fish oil or control diets. Furthermore, there were no marked differences in these values whether or not the groups were administered diets containing added alpha-tocopherol. These results suggest that the intake of oxidized fish oil and the supplementation with alpha-tocopherol do not influence the level of lipid peroxidation in the erythrocyte membrane.


Assuntos
Membrana Eritrocítica/efeitos dos fármacos , Óleos de Peixe/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos de Membrana/sangue , Fosfolipídeos/sangue , Vitamina E/farmacologia , Animais , Membrana Eritrocítica/metabolismo , Masculino , Oxirredução , Ratos , Ratos Wistar
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