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Objective

To examine the association of placental levels of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and chromium (Cr) with birth outcomes (birth weight, length, and head circumference, low birth weight [LBW], gestational age, preterm delivery, and small for gestational age [SGA]) in mother-child pairs from the Environment and Childhood (INMA) Project in Spain.

Methods

Metal concentrations were measured in placenta tissue samples randomly selected from five INMA cohorts. Data on birth outcomes were obtained from medical records. Associations were assessed in a sub-sample of 327 mother-infant pairs by regression models adjusted for confounding factors and for all metals simultaneously. Effect modification by sex was also evaluated.

Results

Elevated placental Cd levels (>5.79 vs. <3.30?ng/g) were associated with reduced birth weight (?111.8?g, 95%CI?=??215.6; ?8.06, p-trend?=?0.01) and length (?0.62?cm, 95%CI?=??1.20; ?0.04, p-trend?=?0.02), while a 10% increase in Cd was associated with 1.21-fold increased odds (95%CI?=?1.01; 1.43) of LBW in the global sample but with 14% lower odds (95%CI?=?0.78; 0.96) of preterm delivery in males (Pinteraction?=?0.10). Detected (vs. undetected) Hg was associated with reduced head circumference (?0.49?cm, 95%CI?=??1.00; 0.03) in females (Pinteraction?=?0.03). A 10% increase in placental Mn was associated with slight increases in gestational age (0.04 weeks, 95%CI?=?0.01; 0.07) in the global sample and in head circumference (0.05?cm, 95%CI?=??0.01; 0.10) in females (Pinteraction?=?0.03). Elevated Cr levels (>99.6 vs. <56.1?ng/g) were associated with reduced birth length (?0.68?cm, 95%CI?=??1.33; ?0.04, p-trend?=?0.02) and slightly increased gestational age (0.35 weeks, 95%CI?=??0.07; 0.77, p-trend?=?0.08) in the global sample. As and Pb were detected in few placentas (27% and 13%, respectively) and were not associated with any studied birth outcome.

Conclusions

Data suggest that in utero exposure to Cd, Hg, and Cr could adversely affect fetal growth, whereas Mn and Cr appear to have a positive effect on gestational age. Given the relatively small number of subjects, sex-specific associations should be interpreted with caution.  相似文献   
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AimTo estimate the prevalence of use of progestin-only contraceptive among women who request reversible contraception in Primary Care (PC).DesignMulticentre cross-sectional study.SettingPrimary Care Health Care Centres (Madrid).ParticipantsWomen aged 16-50 years old, users of reversible contraception, who speak Spanish, and had attended the Primary Care Centre in the last year.Main measurementsPrimary outcome: contraceptive method used: Contraception with progestins-only (yes/no). Age, parity, country of origin, type of contraceptive method used, reason for choice, source of information, satisfaction with the contraceptive method. Telephone survey.ResultsA total of 417 women were interviewed. The median age was 30.3 years (SD: 7.7). Spanish 69%, and 82% of participants had secondary or university studies. More than half (57%) were nulliparous. The type of contraceptive used included: progestins only: 14%, combined hormonal contraceptive: 74%, copper IUD: 2%, and condom 10%. The prevalence of use of “progestins-only” was 13.9% (95% CI: 10.6-17.2). Medroxyprogesterone acetate injection was the most progestin-only method used (4.6%), desogestrel oral pill (4.1%), IUD-levonorgestrel IUD (3.9%), and etonogestrel subdermal implant (1.9%). The family doctor was the prescriber in 71% of the women. Satisfaction: high (range 9-10). Using only progestogens was associated with older age, being non-Spanish, breastfeeding, and having a medical contraindication for combined contraception (P < 0.05).ConclusionsThe prevalence of use for progestins was 14%, satisfaction was very high for all contraceptive methods. The user profile for the only progestins-only corresponds to older, and non-Spanish women with conditions such as breastfeeding or contraindications for other contraceptives.  相似文献   
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We report on a 3‐year‐old girl with a microvesicular generalized rash in whom primary infection by parvovirus B19 was demonstrated by seroconversion. To our knowledge, this is the first instance of an eruption arising from parvovirus B19 with this peculiar clinical pattern.  相似文献   
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The discovery of hepatitis C has been a landmark in public health as it brought the opportunity to save millions of lives through the diagnosis, prevention and cure of the disease. The combined work of three researchers, Alter H, Houghton M and Rice C, which set the basis for the diagnosis, treatment and prevention of hepatitis C apart from laying the ground work for a new approach to study infections in general and developing new antiviral agents. This is a story of a transfusion-associated infection. A series of clinical studies demonstrated the existence of an infectious agent associated with hepatitis. That was followed by the identification of what was later known to be the hepatitis C virus (HCV) and the development of diagnostic tests. It all preceded the full molecular identification and demonstration of a causal effect. Finally it ended up with the development and discovery of a new class of therapeutic drugs, the direct acting antivirals, which are now used not only to cure the disease but most probably, to eliminate the problem. This work started with Dr Alter H who demonstrated that a new virus was responsible for the majority of post-transfusion hepatitis followed by Houghton M who cloned the virus and developed the blood test to identify those cases that carried the virus. Finally, the work of Rice C demonstrated that a cloned HCV produced after applying molecular biology techniques could cause long-standing infection and cause the same disease as the one observed in humans.  相似文献   
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The aim of this study was evaluate the dimensional stability of some condensation silicones. The following materials were studied: Coltex/Coltoflax - Coltène, Speedex - Coltène, and Optosil Comfort/Xantopren VL Plus - Kulzer. They were evaluated by dimensional analysis and gas chromatography (GC) performed at the following times: T0, T1, T2, T3, T4, and T5 (immediately after setting, thirty minutes, two hours, twenty four hours, seventy two hours, and seven days after setting, respectively). The dimensional changes were measured directly in the molds using a Mitutoyo microscope. The Coltex fine/Coltoflax and Optosil Comfort/Xantopren VL Plus materials presented dimensional stability for up to thirty minutes after molding, while the Speedex material remained stable for up to two hours after molding. The gas chromatography experiment demonstrated that these materials release ethanol even after clinical setting.  相似文献   
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