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1.
BJOG ; 123(4): 608-16, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25601143

RESUMO

OBJECTIVE: To study the association between duration of second stage of labour and risks of maternal complications (infection, urinary retention, haematoma or ruptured sutures) in the early postpartum period. DESIGN: Population-based cohort study. SETTING AND SAMPLE: We included 72 593 mothers with singleton vaginal deliveries at ≥37 weeks of gestation in cephalic presentation, using the obstetric database from the Stockholm-Gotland region in Sweden, 2008-12. METHODS: Logistic regression analysis. Odds ratios (ORs) with 95% confidence intervals (95% CI) were calculated and adjustments were made for maternal age, body mass index, height, smoking, cohabitation, gestational age, labour induction, epidural analgesia and oxytocin augmentation. RESULTS: Rates of any complication varied by parity from 7.3% in parous women with previous caesarean section, 4.8% in primiparas and 1.7% in parous women with no previous caesarean section. Compared with a second stage <1 hour, the adjusted ORs for any complication (95% CI) in primiparas were for 1 to <2 hours 1.28 (1.11-1.47); 2 to <3 hours 1.54 (1.32-1.79), 3 to <4 hours 1.63 (1.38-1.93) and ≥4 hours 2.08 (1.74-2.49). The corresponding adjusted ORs for parous women without previous caesarean were 2.27 (1.78-2.90), 2.97 (2.09-4.22), 3.65 (2.25-5.94) and 3.16 (1.44-6.94), respectively. The adjusted ORs for women with previous caesarean were for 1 to <2 hours 1.62 (1.13-2.32); 2 to <3 hours 1.56 (1.00-2.43), 3 to <4 hours 2.42 (1.52-3.87), and ≥4 hours 2.31 (1.25-4.24). CONCLUSIONS: Risks of maternal complications in the postpartum period increase with duration of second stage of labour also after accounting for maternal, pregnancy and delivery characteristics. Special attention has to be given to parous women with previous caesarean deliveries.


Assuntos
Cesárea/estatística & dados numéricos , Parto Obstétrico/efeitos adversos , Segunda Fase do Trabalho de Parto , Período Pós-Parto , Infecção Puerperal/epidemiologia , Retenção Urinária/epidemiologia , Adulto , Peso ao Nascer , Parto Obstétrico/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Trabalho de Parto Induzido , Razão de Chances , Gravidez , Prevalência , Fatores de Risco , Suécia/epidemiologia , Fatores de Tempo
2.
Int J Dent Hyg ; 14(3): 215-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25727487

RESUMO

OBJECTIVES: To study preventive care provided to young adults in relation to their estimated risk category over a 3-year period. METHODS: The amount and type of preventive treatment during 3 years was extracted from the digital dental records of 982 patients attending eight public dental clinics. The baseline caries risk assessment was carried out by the patient's regular team in four classes according to a predetermined model, and the team was responsible for all treatment decisions. Based on the variables 'oral health information', 'additional fluoride' and 'professional tooth cleaning', a cumulative score was constructed and dichotomized to 'basic prevention' and 'additional prevention'. RESULTS: More additional preventive care was provided to the patients in the 'low-risk' and 'some risk' categories than to those classified as 'high' or 'very high' risk (OR = 2.0, 95% CI 1.4-3.0; P < 0.05). Professional tooth cleaning and additional fluorides were most frequently employed in the 'low-risk' and 'some risk' categories, respectively. Around 15% of the patients in the high-risk categories did not receive additional preventive measures over the 3-year period. There was an insignificant tendency that patients with additional prevention developed less caries than those that received basic prevention in all risk categories except for the 'very high-risk' group. CONCLUSION: The caries risk assessment process was not accompanied by a corresponding targeted individual preventive care in a cohort of young adults attending public dental service. Further research is needed how to reach those with the greatest need of primary and secondary prevention.


Assuntos
Assistência Odontológica/normas , Cárie Dentária/epidemiologia , Cárie Dentária/prevenção & controle , Assistência Odontológica/estatística & dados numéricos , Registros Odontológicos , Fluoretos Tópicos , Educação em Saúde Bucal , Serviços de Saúde , Humanos , Doenças da Boca/prevenção & controle , Saúde Bucal/educação , Saúde Bucal/estatística & dados numéricos , Higiene Bucal , Odontologia Preventiva/educação , Odontologia Preventiva/estatística & dados numéricos , Estudos Prospectivos , Medição de Risco , Estatísticas não Paramétricas , Suécia/epidemiologia , Adulto Jovem
3.
J Clin Pharm Ther ; 37(6): 686-92, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22924464

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Interventions involving medication reconciliation and review by clinical pharmacists can reduce drug-related problems and improve therapeutic outcomes. The objective of this study was to examine the impact of routine admission medication reconciliation and inpatient medication review on emergency department (ED) revisits after discharge. Secondary outcomes included the combined rate of post-discharge hospital revisits or death. METHODS: This prospective, controlled study included all patients hospitalized in three internal medicine wards in a university hospital, between 1 January 2006 and 31 May 2008. Medication reconciliation on admission and inpatient medication review, conducted by clinical pharmacists in a multiprofessional team, were implemented in these wards at different times during 2007 and 2008 (intervention periods). A discharge medication reconciliation was undertaken in all the study wards, during both control and intervention periods. Patients were included in the intervention group (n = 1216) if they attended a ward with medication reconciliation and review, whether they had received the intervention or not. Control patients (n = 2758) attended the wards before implementation of the intervention. RESULTS AND DISCUSSION: No impact of medication reconciliation and reviews on ED revisits [hazard ratio (HR), 0.95; 95% confidence interval (CI), 0.86-1.04]or event-free survival (HR, 0.96; 95% CI, 0.88-1.04) was demonstrated. In the intervention group, 594 patients (48.8%) visited the ED, compared with 1416 (51.3%) control patients. In total, 716 intervention (58.9%) and 1688 (61.2%) control patients experienced any event (ED visit, hospitalization or death). Because the time to a subsequent ED visit was longer for the control as well as the intervention groups in 2007 than in 2006 (P < 0.05), we re-examined this cohort of patients; the proportion of patients revisiting the ED was similar in both groups in 2007 (P = 0.608). WHAT IS NEW AND CONCLUSION: Routine implementation of medication reconciliation and reviews on admission and during the hospital stay did not appear to have any impact on ED revisits, re-hospitalizations or mortality over 6-month follow-up.


Assuntos
Revisão de Uso de Medicamentos/métodos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Reconciliação de Medicamentos/métodos , Farmacêuticos/organização & administração , Idoso , Feminino , Seguimentos , Hospitalização/estatística & dados numéricos , Hospitais Universitários , Humanos , Masculino , Conduta do Tratamento Medicamentoso/organização & administração , Pessoa de Meia-Idade , Admissão do Paciente , Equipe de Assistência ao Paciente , Alta do Paciente , Readmissão do Paciente/estatística & dados numéricos , Serviço de Farmácia Hospitalar/organização & administração , Estudos Prospectivos , Fatores de Tempo
4.
J Perinatol ; 37(11): 1197-1203, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29138519

RESUMO

OBJECTIVE: Determine time-to-delivery and mode-of-delivery in labor induction among women with unripe cervix. STUDY DESIGN: 7551 nulliparous women with singleton deliveries, ⩾37 weeks, Bishop Score ⩽6, induced with dinoprostone, misoprostol or transcervical single balloon catheter. Linear regression analysis was used to estimate mean time-to-delivery with ß-estimates and 95% confidence intervals with adjustments. Multivariable logistic regression analysis was used to calculate odds of cesarean delivery, instrumental vaginal delivery, maternal and neonatal outcomes. RESULTS: Adjusted mean time-to-delivery was 6.9 and 1.5 h shorter, respectively, when inducing labor with balloon catheter (mean 18.3 h, ß -6.9, 95% confidence intervals; -7.6 to -6.3) or misoprostol (mean 23.7 h, ß -1.5, 95% confidence intervals; -2.3 to -0.8) compared with dinoprostone (mean 25.2 h). There were no significant differences in adverse maternal or infant outcomes between induction methods. CONCLUSIONS: Balloon catheter is the most effective induction method with respect to time-to-delivery in nulliparous women at term compared with prostaglandin methods.


Assuntos
Catéteres , Parto Obstétrico/estatística & dados numéricos , Dinoprostona , Trabalho de Parto Induzido/métodos , Misoprostol , Ocitócicos , Adulto , Maturidade Cervical , Distribuição de Qui-Quadrado , Feminino , Humanos , Gravidez , Estudos Prospectivos , Fatores de Tempo
5.
J Perinatol ; 37(3): 254-259, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27906196

RESUMO

OBJECTIVE: The objective of the study was to examine normal variations of umbilical cord arterial pH by gestational age (GA). STUDY DESIGN: Population-based cohort study of 46 199 infants born from 2008 to 2014 in Stockholm, Sweden, with GA 28 to 42 weeks, Apgar score ⩾7 at 5 min, non-instrumental vaginal delivery, and birth weight for GA⩾3rd and ⩽97th percentile. Quantile regression was used to investigate the associations between GA and infant sex, and pH. RESULTS: The mean umbilical cord arterial pH (s.d.) was 7.29 (0.10), 7.27 (0.07), 7.25 (0.07) and 7.23 (0.07) among infants born at 28 to 31, 32 to 36, 37 to 41 and 42 weeks, respectively. Arterial pH decreased linearly with increasing GA, and female infants had higher pH than male infants (P<0.001). CONCLUSION: Umbilical cord arterial pH varied in a linear fashion by GA and was influenced by infant sex. The provided reference curve taking GA into account may yield a more accurate definition of acidosis at birth.


Assuntos
Sangue Fetal/química , Idade Gestacional , Recém-Nascido Prematuro/sangue , Acidose/sangue , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Masculino , Valores de Referência , Análise de Regressão , Fatores Sexuais , Suécia , Artérias Umbilicais
6.
Nanoscale ; 9(32): 11410-11417, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28678265

RESUMO

Atomic layer deposition on pharmaceutical particles for drug delivery applications is demonstrated using assisted fluidized bed dry powder processing. Complete and conformal layering is achieved on particle sizes from the lower micron to upper nanometer range under near ambient conditions. As few as 2-14 atomic alumina layers alter particle properties: dissolution, dispersibility and heat transfer.


Assuntos
Portadores de Fármacos/síntese química , Sistemas de Liberação de Medicamentos , Tamanho da Partícula , Pós/síntese química , Óxido de Alumínio/química , Budesonida/química , Lactose/química
7.
Int J Epidemiol ; 45(2): 408-416, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26452388

RESUMO

BACKGROUND: Research studies exploring the determinants of disease require sufficient statistical power to detect meaningful effects. Sample size is often increased through centralized pooling of disparately located datasets, though ethical, privacy and data ownership issues can often hamper this process. Methods that facilitate the sharing of research data that are sympathetic with these issues and which allow flexible and detailed statistical analyses are therefore in critical need. We have created a software platform for the Virtual Pooling and Analysis of Research data (ViPAR), which employs free and open source methods to provide researchers with a web-based platform to analyse datasets housed in disparate locations. METHODS: Database federation permits controlled access to remotely located datasets from a central location. The Secure Shell protocol allows data to be securely exchanged between devices over an insecure network. ViPAR combines these free technologies into a solution that facilitates 'virtual pooling' where data can be temporarily pooled into computer memory and made available for analysis without the need for permanent central storage. RESULTS: Within the ViPAR infrastructure, remote sites manage their own harmonized research dataset in a database hosted at their site, while a central server hosts the data federation component and a secure analysis portal. When an analysis is initiated, requested data are retrieved from each remote site and virtually pooled at the central site. The data are then analysed by statistical software and, on completion, results of the analysis are returned to the user and the virtually pooled data are removed from memory. CONCLUSIONS: ViPAR is a secure, flexible and powerful analysis platform built on open source technology that is currently in use by large international consortia, and is made publicly available at [http://bioinformatics.childhealthresearch.org.au/software/vipar/].

8.
Oral Health Prev Dent ; 3(1): 15-23, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15921333

RESUMO

PURPOSE: To analyse caries risk factors of 12-13-year-old children living in Laos, using the computer program Cariogram to illustrate the caries risk profile. In addition, to compare the results with a study performed in Sweden. MATERIALS AND METHODS: One hundred Laotian and 392 Swedish children were included. Interviews were performed to obtain information on diet intake and fluoride use. Saliva was analysed for mutans streptococci, lactobacilli and secretion rate/buffering capacity. Oral hygiene was assessed using the Silness and Löe criteria. Caries prevalence was recorded according to WHO. The data were entered into the Cariogram to determine each child's caries risk, expressed as 'the chance of avoiding caries'. The children were divided into five risk groups. RESULTS: Mean DMFT level of the Laotian children was 4.61 +/- 2.95 and 1.38 +/- 1.97 in the Swedish group. For the risk factors plaque amount, frequency of food intake, saliva secretion rate, buffering capacity and fluoride, the Laotian children had significantly less favourable values compared to the Swedes. Only 6% of Laotian children belonged to the Cariogram low risk group versus 40% of the Swedish children. The mean DMFT for the five Cariogram groups was (from low to high risk) 0.00, 3.00, 3.56, 5.66, 6.11 for the Lao children and 0.31, 1.39, 2.56, 3.03, 2.91 for the Swedish ones. The mean chance of avoiding caries was 37.3% for the Laotians and 69.2% for the Swedish children (p < 0.001). CONCLUSION: According to the 'opinion' of the Cariogram, the Laotian children demonstrated significantly higher caries risk than Swedish children.


Assuntos
Cárie Dentária/epidemiologia , Medição de Risco/métodos , Software , Adolescente , Análise de Variância , Cariostáticos/uso terapêutico , Criança , Índice CPO , Dieta Cariogênica , Feminino , Fluoretos/uso terapêutico , Humanos , Lactobacillus/isolamento & purificação , Laos/epidemiologia , Masculino , Índice de Higiene Oral , Prevalência , Fatores de Risco , Saliva/microbiologia , Saliva/fisiologia , Estatísticas não Paramétricas , Streptococcus mutans/isolamento & purificação , Suécia/epidemiologia
9.
Br J Pharmacol ; 98(3): 930-6, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2480171

RESUMO

1. The secretion of nasal fluid was studied in anaesthetized rats after topical application of capsaicin, and of calcitonin gene-related peptide (CGRP) alone or CGRP in combination with substance P (SP). The flow of nasal fluid was stimulated and the secretions collected by a filter paper technique. The concentrations of SP and CGRP in nasal biopsies were determined after topical or systemic administration of capsaicin. 2. Capsaicin (single dose administration) stimulated nasal secretion in a dose-dependent manner. The effect was inhibited by hexamethonium, lignocaine, or by the tachykinin antagonist (D-Pro2, D-Trp7,9)-SP, but not by atropine, or by a combination of the histamine H1-receptor antagonist chlorpheniramine and the H2-receptor antagonist ranitidine. 3. When applied cumulatively, capsaicin rapidly produced desensitization. The concentrations of SP and CGRP in the nasal mucosa were reduced by capsaicin 6 days after topical or s.c. administration but not 15 min after topical application of desensitizing doses. 4. CGRP did not stimulate the secretion of nasal fluid and did not alter SP-evoked nasal secretion. 5. The inhibition by hexamethonium of the capsaicin-evoked nasal secretion suggests the involvement of ganglionic reflexes. In addition, the inhibition of the response to capsaicin by (D-Pro2,D-Trp7,9)-SP and lidocaine and the depletion of SP and CGRP after capsaicin indicate the involvement of tachykinin-mediated axon reflexes.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Capsaicina/farmacologia , Mucosa Nasal/metabolismo , Substância P/metabolismo , Animais , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Mucosa Nasal/efeitos dos fármacos , Radioimunoensaio , Ratos , Ratos Endogâmicos
10.
J Appl Physiol (1985) ; 74(5): 2456-61, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8393002

RESUMO

We used Evans blue dye to assess the effects of bradykinin on vascular extravasation in nasal mucosa of pathogen-free F344 rats. There was a dose-dependent increase in Evans blue extravasation when bradykinin was delivered by topical instillation in the nose (doses, 25-100 nmol). Only the highest intravenous doses (2 and 5 mumol/kg) of bradykinin caused increased extravasation. When bradykinin was delivered by either route, its effect on extravasation was exaggerated by pharmacological inhibition of the enzymes neutral endopeptidase (NEP) and kininase II [angiotensin-converting enzyme (ACE)]. When bradykinin was instilled locally, the effect of NEP inhibition was predominant; when bradykinin was injected intravenously, the effect of ACE inhibition was predominant. The mechanism of extravasation also varied with the mode of bradykinin delivery: when bradykinin was instilled locally in the nose, the selective neurokinin 1 (NK1) receptor antagonist CP-96,345 markedly inhibited the response, whereas it had no effect on Evans blue extravasation when bradykinin was injected intravenously. We conclude that bradykinin causes dose-related increases in Evans blue dye extravasation in the nose and that these effects are exaggerated when NEP and ACE are inhibited. Topically instilled bradykinin causes vascular extravasation to a large extent via NK1 receptor stimulation, thus suggesting a major role for tachykinins released from sensory nerve endings.


Assuntos
Bradicinina/farmacologia , Mucosa Nasal/metabolismo , Peptídeo Hidrolases/fisiologia , Receptores de Neurotransmissores/fisiologia , Animais , Compostos de Bifenilo/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Captopril/farmacologia , Azul Evans , Glicopeptídeos/farmacologia , Histocitoquímica , Mucosa Nasal/efeitos dos fármacos , Neprilisina/antagonistas & inibidores , Ratos , Ratos Endogâmicos F344 , Receptores da Neurocinina-2 , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo
11.
Regul Pept ; 49(2): 159-66, 1993 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-7510897

RESUMO

We studied the effect of the locally administered glucocorticoid budesonide on plasma extravasation induced by capsaicin and by substance P (SP) in the nasal mucosa of pathogen-free rats. Using Evans blue dye as a tracer, we measured plasma extravasation induced by capsaicin (150 micrograms kg-1 i.v.) or SP (0.5 and 2.5 micrograms kg-1 i.v.) in the rat naso- and maxilloturbinates after pretreatment with budesonide (0.1-50 micrograms twice/day for 2 days in the right nostril; 50 micrograms only for SP) or its vehicle. We found that budesonide inhibits plasma extravasation induced by capsaicin in a dose-dependent fashion in the nasal cavity. After the highest dose (50 micrograms) of budesonide, the values of Evans blue in the nasal mucosa were not different from the values observed after capsaicin vehicle alone. Budesonide also reduced plasma extravasation induced by capsaicin in the trachea and the urinary bladder of the rats in a dose-dependent fashion. Budesonide (50 micrograms) delivered to the nose inhibited the plasma extravasation caused by 0.5 but not by 2.5 micrograms SP kg-1 in the nasal mucosa. We conclude that the postjunctional part of the neurogenic pathway is a target for glucocorticoid antiinflammatory action in the nasal mucosa, at least of the rat. Budesonide's effect on organs other than the nose can be explained by systemic absorption.


Assuntos
Anti-Inflamatórios/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Capsaicina/antagonistas & inibidores , Mucosa Nasal/efeitos dos fármacos , Pregnenodionas/farmacologia , Substância P/antagonistas & inibidores , Administração Tópica , Animais , Budesonida , Relação Dose-Resposta a Droga , Azul Evans , Glucocorticoides , Injeções Intravenosas , Masculino , Mucosa Nasal/irrigação sanguínea , Ratos , Ratos Endogâmicos F344
12.
Neuropeptides ; 28(5): 309-15, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7541516

RESUMO

Substance P (SP) evokes fluid secretion and plasma extravasation when applied to the nasal mucosa of rats. SP and another tachykinin, neurokinin A (NKA), are degraded in vitro by neutral endopeptidase (NEP) and angiotensin-1-converting enzyme (ACE). In this study, NKA or SP were applied locally to the nasal mucosa of rats. Subsequent fluid secretion was measured by a filter paper technique. Plasma exudation was derived as the recovery of intravenous (i.v.) administered 125I-albumin from the fluid-containing filter papers. In order to inhibit enzymatic degradation of the tachykinins by NEP and ACE, the rats were treated with i.v. administered phosphoramidon or captopril respectively or their combination. SP evoked fluid secretion that was augmented by phosphoramidon and further enhanced by adding captopril. NKA evoked nasal fluid secretion less effectively than SP and the effect was unaffected by peptidase inhibition. SP, but not NKA, evoked increased plasma exudation but only after pre-treatment with phosphoramidon.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Mucosa Nasal/metabolismo , Inibidores de Proteases/farmacologia , Taquicininas/farmacologia , Inibidores da Enzima Conversora de Angiotensina , Animais , Captopril/farmacologia , Relação Dose-Resposta a Droga , Glicopeptídeos/farmacologia , Masculino , Mucosa Nasal/efeitos dos fármacos , Neprilisina/antagonistas & inibidores , Neprilisina/metabolismo , Neurocinina A/farmacologia , Peptidil Dipeptidase A/metabolismo , Ratos , Ratos Sprague-Dawley , Substância P/farmacologia
13.
Eur J Pharmacol ; 161(1): 37-43, 1989 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-2566487

RESUMO

Histamine (dihydrochloride or free base), mannitol or sodium chloride applied topically to the nasal mucosa of anaesthetized rats stimulated the secretion of fluid in a dose-dependent manner. Compound 48/80 applied in the same way and histamine given s.c. failed to evoke secretion. The secretion evoked by topically applied histamine was resistant to pretreatment with H1 and H2 receptor antagonists i.p. Furthermore, the secretion evoked by histamine and sodium chloride was resistant to pretreatment with atropine i.p. or lidocaine topically. The secretion evoked by mannitol or by sodium chloride was not reduced by H1 receptor antagonists and was not significantly different from that obtained after challenge with histamine of equivalent osmolality. We conclude that the response to topically applied histamine reflects the hyperosmolarity of the compounds applied and not the effect of histamine on histamine receptors.


Assuntos
Histamina/farmacologia , Soluções Hipertônicas/farmacologia , Mucosa Nasal/metabolismo , Animais , Relação Dose-Resposta a Droga , Antagonistas dos Receptores Histamínicos H1/farmacologia , Masculino , Manitol/farmacologia , Mucosa Nasal/efeitos dos fármacos , Concentração Osmolar , Ratos , Ratos Endogâmicos , Cloreto de Sódio/farmacologia
14.
J Chromatogr A ; 824(2): 205-10, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9818433

RESUMO

Eighteen 4-hydroxy-3-methoxyphenyl (guaiacyl) compounds in wood smoke from spruce, and 18 4-hydroxy-3,5-dimethoxyphenyl (syringyl) analogues in birchwood smoke were analysed. Smoke samples were taken by a gas syringe from wood burning under varying but more or less choked conditions in laboratory pot experiments. Retention index data for a methylsilicone column and basic mass spectral data are given for all compounds. Retention index in combination with molecular mass and structure-specific fragment ions greatly facilitates qualitative analysis. The syringyl and guaiacyl analogues differ by 240 units in retention index and the matching structure-specific ions in their mass spectra by 30 mass units. The identified methoxyphenols differ in the structure of the sidechain, which may be lacking, an alkyl group, an alkenyl group, a carbonyl-containing group or an alcoholic moiety. The proportions between these groups of compounds varied strongly with combustion conditions whereas the proportions of phenols within them were quite specific for each group. The phenols with reactive olefinic linkages in the sidechain were present in larger proportions than reported in other studies of methoxyphenols.


Assuntos
Poluentes Atmosféricos/análise , Cromatografia Gasosa/métodos , Lignina/análise , Espectrometria de Massas/métodos , Fenóis/análise , Fumaça/análise , Madeira , Incêndios , Lignina/química , Fenóis/química
15.
Sci Total Environ ; 116(1-2): 195-201, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1384124

RESUMO

Samples of urban air hydrocarbons were taken on specifically made adsorbent cartridges and analysed by gas chromatography after thermal desorption. The four isomeric butenes and 1,3-butadiene were favourably resolved and separated from the abundant alkanes on an aluminium oxide PLOT column. The concentrations of butadiene, reflecting outdoor urban exposure, were in the range of 0.5-5 micrograms/m3. An approximate 1:4 ratio was observed between butadiene and propene which both originate predominantly from vehicle exhaust. The four butenes made up approximately 50% of the propene concentration in exhaust-polluted air, with methylpropene greater than 1-butene greater than trans-2-butene greater than cis-2-butene. Petrol vapour contributed less than exhaust but about five times more to the 2-butenes than to methylpropene and 1-butene. The highest exposure levels of butadiene and butenes were consistently observed in the vicinity of exhaust pipes and petrol-fuelled vehicles.


Assuntos
Poluentes Atmosféricos/análise , Butadienos/análise , Butanos/análise , Saúde da População Urbana , Cromatografia Gasosa/métodos , Exposição Ambiental , Humanos , Isomerismo , Suécia , Emissões de Veículos
16.
Sci Total Environ ; 277(1-3): 69-75, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11589408

RESUMO

Ten prominent dimethoxyphenols were determined in birchwood smoke from choked and open laboratory burning and in chimney smoke from a tiled stove. The structures of the methoxyphenols are similar to those of the well-known tocopherol and ubiquinol antioxidants. The 2,6-dimethoxyphenols characterising hardwood smoke are stronger antioxidants than the corresponding 2-methoxyphenols present mainly in softwood smoke. The antioxidant activity is highest for the 2,6-dimethoxyphenols with 4-alkenyl and 4-alkyl groups, which constitute 60-70% of the total amount of dimethoxyphenols. Phenolic antioxidants are scavengers of oxygen radicals and should be considered when health hazards of small-scale incomplete biomass burning are estimated.


Assuntos
Poluentes Atmosféricos/análise , Antioxidantes/análise , Fenóis/análise , Madeira , Biomassa , Cromatografia Gasosa , Monitoramento Ambiental , Sequestradores de Radicais Livres , Incineração , Peroxidação de Lipídeos
17.
Environ Pollut ; 79(3): 215-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-15091881

RESUMO

Monoterpenes released to air were determined during single-log barking of timber at a saw-mill and during tumble drum barking of pulpwood at a TMP mill. Characteristic proportions of fourteen compounds were assessed by adsorbent sampling and gas chromatography. For Scots pine (Pinus sylvestris), the bicylic monoterpenes alpha-pinene and 3-carene predominated. For Norway spruce (Picea abies), alpha-pinene followed by beta-pinene were the major components. The proportions of beta-phellandrene and myrcene from spruce were remarkably high from barking compared to wood processing. Environmental aspects on the emissions are discussed.

18.
Environ Pollut ; 79(3): 219-23, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-15091882

RESUMO

Monoterpenes emitted to air from two Swedish kraft (sulphate) pulp-mills were determined by sampling on the Tenax adsorbent followed by laboratory analysis using thermal desorption combined with high-resolution gas chromatography. The composition of the terpenes was found to be similar in the emissions from various parts of the process as well as in the mill plume. The bicyclic terpenes alpha-pinene and 3-carene, originating principally from wood of Scots pine (Pinus sylvestris), predominated among the thirteen assessed hydrocarbon monoterpenes. Terpinolene was the most prominent among the particularly reactive terpenes with a lifetime in ozone-rich air of only a few minutes. The rapid formation of photooxidants by chemical reactions of the terpenes with other components of the mill plume is discussed. It is concluded that a variety of phytotoxic photooxidants are formed which may contribute significantly to forest decline within 50 km of mills located along coasts.

19.
Sci Total Environ ; 91: 49-57, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2321000

RESUMO

Hydrocarbons in air were determined at pioneering European service stations equipped with vapour recovery systems. Vapour recovery was found capable of eliminating 99% of exposure during refuelling and greater than 95% of emissions to air. Vapour recovery is now being rapidly introduced at Swedish service stations as a result of demands concerning environmental and health hazards. The analytical technique used permitted samples corresponding to a single refuelling procedure to be analyzed. Sampling on an adsorbent tube was followed in the laboratory by thermal desorption and capillary gas chromatography. All prominent hydrocarbons were well separated on a methylsilicone phase. These include benzene and the alkenes of special interest with respect to health hazards. The particular importance of alkenes with respect to the formation of ozone and other photooxidants is discussed. The four isomeric butenes and the six isomeric pentenes were determined and found to constitute approximately 10% by weight of the petrol vapour. The highly reactive 2-alkenes were more abundant than the 1-alkenes.


Assuntos
Poluentes Atmosféricos/análise , Alcanos/análise , Alcenos/análise , Gasolina , Petróleo , Cromatografia Gasosa , Oxirredução , Suécia , Volatilização
20.
Sci Total Environ ; 207(1): 63-7, 1997 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-9397601

RESUMO

The concentration of isoprene inside a small-sized parked private car with one person was found to be of the order of 20 micrograms/m3. Isoprene was then the major non-methane volatile hydrocarbon except in strongly traffic-polluted parking places. On driving, with intermediate fan ventilation, the isoprene levels were one order of magnitude lower. In the empty car, the concentrations were still much lower, proving that isoprene originates predominantly from expired air. Air samples were taken on triple-layer adsorbent cartridges and were analysed for volatile hydrocarbons by gas chromatography after thermal desorption. The analytical aluminium oxide column permitted simultaneous determination of a range of reported traffic-emitted hydrocarbons including the carcinogenic 1,3-butadiene and benzene.


Assuntos
Ar/análise , Butadienos/análise , Hemiterpenos , Pentanos , Testes Respiratórios , Cromatografia Gasosa/métodos , Humanos , Hidrocarbonetos/análise , Masculino , Emissões de Veículos/análise
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