Sorbent-assisted liquid-liquid extraction (Chem-Elut) of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans in the lipid fraction of human blood plasma.

This work compares two lipid extraction methods for determining 24 polychlorinated biphenyls (PCBs), seven dibenzo-p-dioxins (PCDDs) and ten dibenzofurans (PCDFs) in human blood plasma. The first method was based on conventional liquid-liquid partitioning with chloroform-methanol and the other made use of a sorbent (Chem-Elut) to facilitate the partitioning of lipids into a mixture of hexane and 2-propanol. A multi-layer-silica column including acid- and base-impregnated silica gel was used to reduce the amounts of lipid present in the samples before a basic alumina clean-up step and activated carbon fractionation of planar analytes (PCDD/Fs and non-ortho-PCBs) and non-planar analytes (including ortho-chlorinated PCBs). Gas chromatography coupled to high resolution mass spectrometry was used to identify and quantify the analytes in the two fractions. The wet weight based concentrations obtained by the two methods were in agreement but both methods suffer from large organic solvent consumption. The toxic equivalencies derived for PCBs and PCDD/Fs using the two methods were also in agreement. However, the chloroform-methanol method gave slightly higher lipid recoveries, although with greater variation, than the sorbent-assisted method. Nevertheless, despite giving lower lipid recoveries, the sorbent-assisted method has advantages in ease of use and applicability to whole blood samples. The formation of emulsions was avoided with the Chem-Elut method, which probably explains the lower variability in the lipid determinations.

A role for the C3a anaphylatoxin receptor in the effector phase of asthma.

Asthma is a chronic inflammatory disease of the airways and lung mucosa with a strong correlation to atopy and acquired (IgE) immunity. However, many features of bronchial asthma, such as smooth muscle contraction, mucus secretion and recruitment of inflammatory cells, are consistent with the actions of complement anaphylatoxins, in particular C3a and C5a. Complement activation forms a central core of innate immune defence against mucosal bacteria, viruses, fungi, helminths and other pathogens. As a system of 'pattern-recognition molecules', foreign surface antigens and immune complexes lead to a proteolytic cascade culminating in a lytic membrane attack. The anaphylatoxins C3a and C5a are liberated as activation byproducts and are potent pro-inflammatory mediators that bind to specific cell surface receptors and cause leukocyte activation, smooth muscle contraction and vascular permeability. Here we show that in a murine model of allergic airway disease, genetic deletion of the C3a receptor protects against the changes in lung physiology seen after allergen challenge. Furthermore, human asthmatics develop significant levels of ligand C3a following intra-pulmonary deposition of allergen, but not saline. We propose that, in addition to acquired immune responses, the innate immune system and complement (C3a in particular) are involved in the pathogenesis of asthma.

Determination of aflatoxicol in human urine by immunoaffinity column clean-up and liquid chromatography.

A method for the determination of aflatoxicol in urine has been developed. The urine samples were cleaned up by an automated procedure using immunoaffinity columns before analysis by high-performance liquid chromatography and fluorescence detection. Post-column derivatization with bromine allowed the simultaneous determination of aflatoxicol and aflatoxins B1, B2, G1, G2, M1, and Q1. Average recovery of aflatoxicol was 99% in the range 4-40 pg ml-1 of spiked urine samples. The relative standard deviations were all between 1% and 3%. The limit of detection was 1 pg ml-1 urine. Authentic samples from exposed feed-factory workers were analysed, but aflatoxin levels were found to be below the detection limit.

The Stockholm birth centre trial: maternal and infant outcome.

OBJECTIVE: To compare an in-hospital birth centre with standard maternity care regarding medical interventions and maternal and infant outcome. BACKGROUND: The birth centre care was characterised by comprehensive antenatal, intrapartum and postpartum care with the same team of midwives, restricted use of medical technology, and discharge within 24 h after birth. METHODS: Of 1860 women meeting low risk medical criteria in early pregnancy and interested in birth centre care, 928 were randomly allotted birth centre care and 932 standard maternity care. Data were collected mainly from hospital records, and analysis was by intention-to-treat. RESULTS: Of the women in the birth centre group, 13% were transferred antenatally and 19% intrapartum. No statistical differences were observed in maternal morbidity or in perinatal mortality, neonatal morbidity, Apgar score or infant admissions to neonatal care. Perinatal mortality, defined as intrauterine death after 22 weeks of gestation and infant death within seven days of birth, occurred in eight cases (0.9%) in the birth centre group and in two cases (0.2%) in the standard care group (OR 4.04, 95% CI 0.80 to 39.17; P = 0.11). Subgroup analysis showed that a larger proportion of first-born babies in the birth centre group (15.6%) were admitted for neonatal care than in the standard care group (9.5%) (P = 0.003), whereas the converse was the case for the newborns of multiparous women: 4.7% and 8.4%, respectively (P = 0.04). The overall rates of operative delivery (e.g. caesarean section, vacuum extraction and forceps), 11.1% in the birth centre group and 13.4% in the standard care group, did not differ statistically (P = 0.12), but obstetric analgesia, induction, augmentation of labour and electronic fetal monitoring were less frequently used in the birth centre group. Labour was 1 h longer in the birth centre group. CONCLUSION: Birth centre care was associated with less medical interventions than standard care without any statistically significant differences in health outcomes. However, the excess of perinatal deaths and of morbidity in primigravidas' infants in the birth centre group gives cause for concern and necessitates further studies.

A randomized controlled study of birth center care versus standard maternity care: effects on women's health.

BACKGROUND: The safety of birth center care for low-risk women is an important issue, but it has not yet been studied in randomized controlled trials. Our purpose was to evaluate the effect of birth center care on women's health during pregnancy, birth, and 2 months postpartum by comparing the outcomes with those of women experiencing standard maternity care in the greater Stockholm area. METHODS: Of 1860 women, 928 were randomly allocated to birth center care and 932 to standard antenatal, intrapartum, and postpartum care. Information about medical procedures and health outcomes was collected from clinical records, and a questionnaire was mailed to women 2 months after the birth. Analysis was by "intention to treat;" that is, all antenatal, intrapartum, and postpartum transfers were included in the birth center group. RESULTS: During pregnancy, birth center women made fewer visits to midwives and doctors, experienced fewer tests, and reported fewer health problems. No statistical difference occurred in hospital admissions (4.8%) compared with the control group (4.7%). During labor, birth center women used more alternative birth positions, had longer labors, and did not differ in perineal lacerations. In both groups 1.7 percent of women developed complications, requiring more than 7 days of hospital care after the birth. During the first 2 postpartum months, about 20 percent of women in both groups saw a doctor for similar types of health problems, and no statistical difference occurred in hospital readmissions, 1.4 and 0.8 percent in the birth center and control groups, respectively. CONCLUSION: The results suggest that birth center care is effective in identifying significant maternal complications and as safe for women as standard maternity care.

Volatile metabolites produced by two fungal species cultivated on building materials.

Two fungal species commonly found in indoor environments, Penicillium commune and Paecilomyces variotü, were cultivated on pine wood and on a combination of gypsum board and mineral wool. Air from the cultures was adsorbed on Tenax TA and analysed using thermal desorption-cold trap injection gas chromatography. Identification of the produced volatile metabolites was performed by mass spectrometry. The majority of the compounds produced were alcohols, ketones, ethers and terpenoid compounds. Commonly produced metabolites were 2-methyl-1-propanol, 3-methyl-1-butanol, 1-hexanol, 2-heptanone, 2-pentanone and 2,5-dimethyl-furan. The production was highly influenced by both medium and species.

Determination of aflatoxins in dust and urine by liquid chromatography/electrospray ionization tandem mass spectrometry.

A liquid chromatography/electrospray ionization tandem mass spectrometry method is described for the determination of aflatoxins B1, B2, G1 and G2. Samples of naturally contaminated airborne dust and spiked urine were cleaned up on immunoaffinity columns and analysed by liquid chromatography using either mass spectrometry detection or post-column derivatization with bromine and fluorescence detection. With tandem mass spectrometry, detection limits (S/N = 3) calculated as amount ejected on column were: aflatoxin B1 4 pg, B2 4 pg, G1 5 pg, and G2 10 pg.

Experience of childbirth in birth center care. A randomized controlled study.

BACKGROUND: The objective of the study was to compare women's use of obstetric analgesia, experience of pain in labor, and other aspects of the childbirth experience at an in-hospital birth center and with standard maternity care. The birth center care was characterized by comprehensive antenatal, intrapartum and post partum care, on the same premises with a home-like environment and the same team of midwives, restricted use of medical technology and pharmacological pain relief, and discharge within 24 h after birth. METHODS: Of 1,230 women interested in birth center care and meeting low-risk medical criteria in early pregnancy, 617 were randomly allotted birth center care (EG) and 613 standard obstetric care (CG). Data were collected by questionnaires two months post partum, and hospital records. RESULTS: EG women used less pharmacological pain relief than CG women, but no difference was observed concerning the retrospective attitude to pain, or among primiparas, to the intensity of pain experienced. EG multiparas experienced pain in labor as more intense, than did CG multiparas, probably because of a more negative prenatal attitude to labor pain. EG women experienced more support from the midwife, and a greater freedom in expressing their feelings during the birth than CG women. EG primiparas were more satisfied with their own achievement and felt more involved in the birth process than CG primiparas. No differences were observed between the groups regarding overall experience of childbirth, anxiety during the birth or support from husband. CONCLUSION: Birth center care gave women interested in a natural childbirth, by avoiding pharmacological pain relief, greater opportunity to give birth according to their prenatal wishes, and it contributed to a slightly more positive birth experience.

No effect of birth centre care on either duration or experience of breast feeding, but more complications: findings from a randomised controlled trial.

OBJECTIVE: to study the effect of birth centre care on the duration of breast feeding, breast feeding complications, and women's experiences of breast feeding. DESIGN: randomised controlled trial. SETTING: in-hospital birth centre at South Hospital, Stockholm, and standard obstetric care in the Greater Stockholm area. SUBJECTS: 1230 women with expected date of birth between October 1989 and February 1992, interested in participating in a birth centre trial, and meeting medical low-risk criteria. 617 women were allocated to the experimental group offered birth centre care (EG), and 613 to the control group offered standard obstetric care (CG). MAIN OUTCOME MEASURES: duration of breast feeding, breast feeding complications such as sore nipples, engorgement, milk stasis, and mastitis, and women's experiences of breast feeding. FINDINGS: no difference was found between EG and CG in the duration of breast feeding. Ninety-three per cent in both groups were breast feeding exclusively two months post partum. The average number of months of breast feeding, exclusively or partly, when investigated one year after the birth was 8.6 in EG and 8.5 in CG. No difference was observed in women's experiences of breast feeding, but rather more women in EG than in CG reported sore nipples, 36% and 30% respectively (p = 0.03), and milk stasis, 26% and 19% respectively (p = 0.002). CONCLUSIONS: birth centre care had no effect on the duration of breast feeding, or on women's experiences of breast feeding. Prenatal attitudes were probably more significant predictors of these outcomes than differences in the two modes of maternity care in this population of highly breast feeding-motivated women. The larger proportion of sore nipples and milk stasis in the EG might have been due to earlier discharge, or to midwives less skilled in assisting with breast feeding at the birth centre than in the postpartum wards.

Characteristics of women choosing birth center care.

The purpose of this study was to describe the characteristics of women choosing alternative maternity care compared with women who preferred conventional care. The former group of women had their antenatal, intrapartum and postpartum care at birth center in Stockholm, Sweden. Characteristics of the birth center care were continuity of care, restriction of medical technology, parental responsibility and self care. Altogether 1086 women enrolled for birth center care were included in the Alternative Group (AG). A sample of 630 was selected from among pregnant women who preferred conventional care (CG). Both groups filled in a structured questionnaire, and the response rate was 100% (1086) in the AG and 70% (441) in the CG. Besides having a more critical attitude to conventional procedures of maternity care, women in the AG were older, better educated and had other professions than CG women. They were in better physical health, and tended to be less anxious when thinking of the approaching birth and motherhood. They had more positive expectations of the coming birth, and a greater interest in not being separated from the newborn and the rest of the family immediately after the birth. They were also more interested in being actively involved in their own care. Generally speaking, AG women were more concerned about the psychological aspects of childbirth. No differences were found between the groups regarding civil status, proportion of native Swedes, or parity. Women whose characteristics coincide with those of the AG may be a growing proportion of the female population, due to better education and a growing concern about the disease orientation of maternity care.(ABSTRACT TRUNCATED AT 250 WORDS)

Women's satisfaction with birth center care: a randomized, controlled study.

This randomized, controlled trial compared women's satisfaction with care at an in-hospital birth center with standard obstetric care in Stockholm. Subjects were 1230 women with an expected date of birth between October 1989 and February 1992, who expressed interest in birth center care, and who were medically low risk. The intervention was the random allocation of maternity care at the birth center or standard obstetric care. Birth center women expressed greater satisfaction with antenatal, intrapartum, and postpartum care, especially psychological aspects of care. Of these women, 63 percent thought that the antenatal care had raised their self-esteem, versus 18 percent of the control group. Eighty-nine percent of the experimental group would prefer birth center care for any future birth, and 46 percent of the control group would prefer standard care. Birth center care successfully meets the needs of women who are interested in natural childbirth and active involvement in their own care, and are concerned about the psychological aspects of birth.

Occupational exposure to chromium, copper and arsenic during work with impregnated wood in joinery shops.

CCA-impregnated timber contains copper, chromium and arsenic (CCA), and occupational exposure to wood dust as well as the CCA compounds may occur in work with such timber. Dust from commercially available impregnated wood has been found to contain hexavalent chromium, which is regarded as a carcinogen. Apart from determinations of the total amounts of the CCA compounds, specific determination of hexavalent chromium is therefore essential. Selective methods have been applied for control of the work environment in six joinery shops. The mean exposure to wood dust was found to be below 1 mg m-3. The mean airborne concentration of arsenic around various types of joinery machines was in the range from 0.54 to 3.1 micrograms m-3. No hexavalent chromium was detected in any samples and no increased concentrations of arsenic were found in urine from the workers. The presence of arsenic in the work-room air must be considered for appropriate assessment of the occupational environment in joinery shops.

Thermal desorption cold trap-injection in high-resolution gas chromatography: multivariate optimization of experimental conditions.

In studies of low concentrations of volatile compounds in air, the method of adsorption on porous polymers and determination by thermal desorption cold trap-injection high-resolution gas chromatography is finding increasing application. Factors considered important for injection and chromatographic separation of volatile compounds by this method were investigated with the use of multivariate techniques. For the amount injected on to the chromatographic column, the factors of main importance were found to be the temperature of the injection block, the thickness of the internal coating of the cold trap and the flow-rate. Strong interaction effects were noted. For the sharpness of the chromatographic peaks, the flow-rate was the most important factor.

Warm tub bath after spontaneous rupture of the membranes.

Increasing numbers of pregnant women take a warm bath during labor. Yet few evaluations have addressed benefits claimed and possible risks of this practice. Using retrospective data from a continuing trial at a birth center in Stockholm, we compared 89 women who took a warm bath after spontaneous rupture of the membranes at term with 89 women who had the same interval from spontaneous membrane rupture to delivery and who did not bathe. No statistical difference was observed between the groups with respect to infections, asphyxia or respiratory problems in the newborn infant, or maternal signs of amnionitis. However, a tendency toward more complications was observed in the bathing group. Babies born more than 24 hours after rupture of membranes had significantly lower Apgar scores at 5 minutes in the bathing group than in the control group. As a result of our review of the sparse literature on this practice and the data from this study, we have modified the bathing policy at the birth center from a rather enthusiastic to a more cautious approach. Recommendations about the use of a warm bath in labor will require further investigation, such as randomized trials with large numbers of subjects.