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31.
Rebecca Gomperts Kirsten van der Vleuten Kinga Jelinska Cecilia Veiera da Costa Kristina Gemzell-Danielsson Gunilla Kleiverda 《Contraception》2014
Objective
To evaluate the need for and outcome of self-administered medical abortion with mifepristone and misoprostol in Brazil, provided through Women on Web, a global telemedicine abortion service.Study Design
A retrospective case review of women from Brazil who contacted Women on Web in 2011. Information from the online consultation, follow-up questionnaire and emails were used to analyze data including demographics, gestational age, outcome of the medical abortion and symptoms that lead to surgical interventions.Results
The Women on Web website had 109779 unique visitors from Brazil, 2104 women contacted the helpdesk by email. Of the 1401 women who completed the online consultation, 602 women continued their request for a medical abortion. Of the 370 women who used the medicines, 307 women gave follow-up information about the outcome of the medical abortion. Of these, 207 (67.4%) women were 9 weeks or less pregnant, 71 (23.1%) were 10, 11 or 12 weeks pregnant, and 29 (9.5%) women were 13 weeks or more pregnant. There was a significant difference in surgical intervention rates after the medical abortion (19.3% at < 9 weeks, 15.5% at 11–12 weeks and 44.8% at > 13 weeks, p=.06). However, 42.2% of the women who had a surgical intervention had no symptoms of a complication.Conclusion
There is large need for medical abortion in Brazil. Home use of mifepristone and misoprostol provided through telemedicine is safe and effective. However, after 13 weeks gestation, there is an increased risk of surgical intervention that may be due to the regimen used and local clinical practices in Brazil.Implications
The current study shows that there is an unmet need for medical abortion in Brazil, a country with legal restrictions on access to safe abortion services. Telemedicine can help fulfill the need and self administration of medical abortion is safe and effective even at late first trimester abortion. Prospective trials are needed to establish safety, effectiveness and acceptability of home use of medical abortion beyond 12 weeks of pregnancy. 相似文献32.
Todd A. Jusko Renata Sisto Ana-Maria Iosif Arturo Moleti Sonˇa Wimmerová Kinga Lancz Juraj Tihányi Eva ?ov?iková Beata Drobná L’ubica Palkovi?ová Dana Jure?ková Kelly Thevenet-Morrison Marc-André Verner Dean Sonneborn Irva Hertz-Picciotto Tomá? Trnovec 《Environmental health perspectives》2014,122(11):1246-1252
Background: Some experimental and human data suggest that exposure to polychlorinated biphenyls (PCBs) may induce ototoxicity, though results of previous epidemiologic studies are mixed and generally focus on either prenatal or postnatal PCB concentrations exclusively.Objectives: Our aim was to evaluate the association between pre- and postnatal PCB concentrations in relation to cochlear status, assessed by distortion product otoacoustic emissions (DPOAEs), and to further clarify the critical periods in development where cochlear status may be most susceptible to PCBs.Methods: A total of 351 children from a birth cohort in eastern Slovakia underwent otoacoustic testing at 45 months of age. Maternal pregnancy, cord, and child 6-, 16-, and 45-month blood samples were collected and analyzed for PCB concentrations. At 45 months of age, DPOAEs were assessed at 11 frequencies in both ears. Multivariate, generalized linear models were used to estimate the associations between PCB concentrations at different ages and DPOAEs, adjusting for potential confounders.Results: Maternal and cord PCB-153 concentrations were not associated with DPOAEs at 45 months. Higher postnatal PCB concentrations at 6-, 16-, and 45-months of age were associated with lower (poorer) DPOAE amplitudes. When all postnatal PCB exposures were considered as an area-under-the-curve metric, an increase in PCB-153 concentration from the 25th to the 75th percentile was associated with a 1.6-dB SPL (sound pressure level) decrease in DPOAE amplitude (95% CI: –2.6, –0.5; p = 0.003).Conclusions: In this study, postnatal rather than maternal or cord PCB concentrations were associated with poorer performance on otoacoustic tests at age 45 months.Citation: Jusko TA, Sisto R, Iosif AM, Moleti A, Wimmerová S, Lancz K, Tihányi J, Šovčíková E, Drobná B, Palkovičová L, Jurečková D, Thevenet-Morrison K, Verner MA, Sonneborn D, Hertz-Picciotto I, Trnovec T. 2014. Prenatal and postnatal serum PCB concentrations and cochlear function in children at 45 months of age. Environ Health Perspect 122:1246–1252; http://dx.doi.org/10.1289/ehp.1307473 相似文献
33.
Kinga Karlinger Ádám Domonkos Tárnoki Dávid László Tárnoki Anne Polvi Anna-Elina Lehesjoki Andrea Kelemen László Szegedi Eszter Turányi Anita Kamondi Anna Szűcs 《Journal of neurology》2014,261(10):1911-1916
We present a clinical, neuro-radiological and genetic study on a family with members suffering from an autosomal dominantly inherited syndrome characterised by epilepsy, cerebral calcifications and cysts, bone abnormalities; progressive neuro-cognitive deterioration and paranasal sinusitis. This syndrome shares several features with leukoencephalopathy with calcifications and cysts also called Labrune syndrome and the condition of cerebroretinal microangiopathy with calcifications and cysts (CRMCC; Coats plus syndrome). Genetic studies in this family did not reveal mutations in the CTC1 gene defected in CRMCC. We interpret our results as those supporting recent findings that despite clinical similarities, late-onset Labrune and Coats plus syndrome might be distinct entities. This family may have Labrune syndrome or a yet unclassified entity; exploration of similar cases could help classifying this one, and related conditions. 相似文献
34.
35.
Tadeusz Knych Andrzej Mamala Pawe Kwaniewski Grzegorz Kiesiewicz Beata Smyrak Marek Gnieczyk Artur Kawecki Kinga Korze Eliza Sieja-Smaga 《Materials》2022,15(3)
Intensive research is underway worldwide to develop new conductive materials for applications in the power industry. Such tests aim to increase the electrical conductivity of materials for conductors and cables, thus increasing the current carrying capacity of the line and reducing the loss of electricity transmission. The scientific discovery of recent years, graphene, one of the allotropic types of carbon with very high electrical and thermal conductivity and mechanical strength, creates great opportunities for designing and producing new materials with above-standard operational properties. This project concentrates on developing technology for manufacturing aluminum-graphene and copper-graphene composites intended to be used to produce a new generation of power engineering conductors. In particular, we present the results of the research on the mechanical synthesis of aluminum-graphene and copper -graphene composites, as well as the results of the electric, mechanical, and structural properties of rods obtained after the extrusion process and wires after the drawing process. 相似文献
36.
Nicotinic acid is a naturally occurring pyridine carboxylic acid, contained in vitamin PP, an essential nutrient for humans and animals, and used as an antipelagic agent. Nicotinic acid can be made from tryptophan by plants and animals but is usually not completely bioavailable. Industrially, nicotinic acid is produced mainly by oxidation of 5-ethyl-2-methylpyridine with nitric acid. One of the by-products of the process is nitrous oxide, a gas that is difficult to recycle and manage, with a greenhouse effect 300 times stronger than CO2. A new technology for the industrial production of nicotinic acid is undoubtedly necessary to meet the needs of green chemistry and not burden the environment. We carried out a literature review on ecological methods to produce nicotinic acid from commercially available raw materials such as 3-methylpyridine and 5-ethyl-2-methylpyridine, especially focusing on those methods with potential industrial applications. 相似文献
37.
Joanna Andrusiak Kinga Mylkie Magorzata Wysocka Jacek
cianowski Andrzej Wolan Marcin Budny 《RSC advances》2021,11(46):28934
A six-step synthesis of xanthohumol (1a) and its d3-derivative (1b) from easily accessible naringenin is reported. The prenyl side chain was introduced by Mitsunobu reaction followed by the europium-catalyzed Claisen rearrangement and base-mediated opening of chromanone gave access to an α,β-conjugated ketone system. Compound 1b was used as an internal standard in stable isotope dilution assays of 1a in two Polish beers.A six-step synthesis of xanthohumol and its d3-derivative from easily accessible naringenin is reported.Xanthohumol (1a, Scheme 1A) is a naturally occurring prenylated chalcone produced by lupulin glands in female inflorescences of hop plants.1 In recent years, 1a has attracted significant attention due to its vast range of biological activities including cancer-preventive, antioxidative, anti-inflammatory, and antiviral.2–8 Such properties combined with low toxicity to the human body make 1a a prospective therapeutic agent, diet supplement, or ingredient of cosmetics.9 Although 1a was isolated from natural sources in 1913,10 the first synthesis of this compound was reported as late as in 2007.11 Several other syntheses have been reported since then, but only minor improvements have been achieved.12–14Open in a separate windowScheme 1The background of the study.Bioactive compounds labeled with stable isotopes (deuterium, carbon-13) are widely applied in metabolomic studies for tracking metabolic pathways and as internal standards in stable isotope dilution assays.15,16 Deuterated compounds are also considered as attractive drug candidates due to the influence of the kinetic isotope effect on pharmacokinetics.17–19 Although approaches to 13C-enriched xanthohumol20,21 and hydrogen/deuterium exchange in 1a22 were reported, no scalable and cost-effective synthesis of the deuterium-labeled derivative of 1a (i.e.1b) has been disclosed to date.Two main challenges have to be faced in the synthesis of 1a: (i) construction of a pentasubstituted aromatic ring containing a prenyl side chain and (ii) selection of suitable protecting groups for phenols. In the case of (i), phloroglucinol is used as a precursor and an acyl-substituent is introduced by Friedel–Crafts acylation with a subsequent Claisen–Schmidt condensation. The prenyl side-chain is introduced by Mitsunobu alkylation, followed by Claisen rearrangement. In the case of (ii), acid-sensitive alkoxymethyl protecting groups, removable under conditions in which 1a does not cyclize to isoxanthohumol (2a), are used most often (Scheme 1A).In this study, we have developed a synthetic approach for the formation of 1a and its deuterated analog 1b. We envisioned that both 1a and 1b can be directly obtained by the base-promoted chromanone ring-opening of 2a or 2b, which in turn can be obtained from easily accessible naringenin (3) (ca. 1 $/1 g) via two-step prenylation and Williamson etherification of the phenolic OH (Scheme 1B). The use of 3 as the starting material is beneficial as only one prenyl substituent has to be introduced.The synthetic route leading to 1a and 1b is depicted in Scheme 2. Our synthesis commenced from naringenin (3), which was selectively converted to diester 4 (Ac2O, pyridine). O-Alkylation of 4 under Mitsunobu conditions (3-methyl-2-butene-1-ol, Ph3P, DIAD), followed by the catalytic Claisen rearrangement of 5 (Eu(fod)3, 1,2-dichloroethane, 80 °C) afforded prenyl-derivative 6. Notably, performing the latter reaction in 1,2-dichloroethane above its boiling point was superior in comparison to earlier reports.23–26 Alkylation of 6 (CH3I, Ag2O or CD3I, Ag2O) afforded 7a/7b in good yields. An alternative approach to 7b involving the alkylation of phenolic OH under Mitsunobu conditions (CD3OD, Ph3P, DIAD) required a large excess of reagents and afforded the product in moderate yield. Basic hydrolysis (KOH, MeOH) of esters afforded isoxanthohumols 2a/2b. Although the chromane ring was stable during the hydrolysis, it could be opened under more harsh conditions (DBU, DMF, 70 °C),27,28 leading to 1a/1b in good yields after a mild acidic workup.Open in a separate windowScheme 2The synthetic route to 1a and 1b.With 1a and 1b in hand, we investigated their MS-fragmentation patterns in electrospray ionization in positive and negative ion modes. The MRM transitions were found by an automatic procedure and they are listed in † for details). In positive ion mode, the most intensive product ions in fragmentation of 1a were ions with m/z values of 178.9, 299.0, 113.0, and 150.9. Corresponding ions with m/z +3 values can be found in the fragmentation of 1b. On the other hand, in the negative ion mode, the same product ions are observed both in the case of 1a and 1b, indicating that the CH3/CD3 groups were lost during fragmentations.The MRM transitions of 1a and 1b
Open in a separate windowOne of the criteria for an effective internal standard is the coelution of the labeled and non-labeled compounds during the HPLC analysis. This is particularly important in case of deuterium-labeled compounds as with the increase in the number of deuterons in the molecule, retention times may be extended. The retention times of 1a and 1b under different HPLC conditions are listed in Entry Conditions Retention time [min] 1a 1b 1 Column: XB-C18, 100 × 3.0 mm, 2.6 μm, 100 Å; flow: 0.55 mL min−1; oven: 35 °C; gradient MeOH/0.1% HCO2H(aq): from 5% MeOH to 95% MeOH 20.030 20.034 2 Column: Ace 5 C18-PFP, 250 × 4.6 mm; flow: 1.0 mL min−1, oven: 35 °C; isocrat. MeOH/0.1% HCO2H(aq): 80 : 20 19.615 19.700 3 Column: polar-C18, 100 × 3.0 mm, 2.6 μm, 100 Å; flow: 0.55 mL min−1; oven: 35 °C; isocrat.: MeOH/0.1% HCO2H(aq): 65 : 35 6.590 6.520
Ionization mode | 1a | 1b | ||
---|---|---|---|---|
Precursor ion | Product ion | Precursor ion | Product ion | |
ESI(+) | 355.0 | 178.9 | 358.0 | 182.0 |
299.0 | 302.0 | |||
113.0 | 115.9 | |||
150.9 | 107.9 | |||
93.0 | 154.0 | |||
ESI(−) | 353.0 | 119.1 | 356.0 | 119.1 |
233.0 | 236.0 | |||
295.1 | 295.2 | |||
218.2 | 175.0 | |||
175.0 | 218.1 | |||
189.2 | 168.2 |