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1.
Dalton Trans ; 50(32): 11113-11122, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34323252

RESUMEN

Four derivatives of 2-(1H-imidazo[4,5-b]phenazin-2-yl)phenol have been synthesized and characterized structurally using X-ray crystallography. Coordination complexes with uranyl (UO22+) and copper (Cu2+) were prepared and absorption/emission spectra detailed. We observed increased fluorescence upon uranyl binding, in stark contrast to rapid quenching observed with the addition of copper. These phenomena have been further examined by DFT computational methods.

2.
Dalton Trans ; 47(4): 1337-1346, 2018 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-29303180

RESUMEN

The fluorescent ligand 1,1'-((1E,1'E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene)) bis(naphthalen-2-ol) (H2L) was used to prepare lanthanide(iii) metal complexes. These were found to self-assemble as triple decker sandwich complexes of the type (Ln2L3), where Ln = Pr(iii), Nd(iii), Sm(iii), Eu(iii), Gd(iii), Tb(iii), Dy(iii), Ho(iii), Er(iii), Yb(iii), or Lu(iii). The structures of the complexes Nd2L3, Gd2L3, Tb2L3, Dy2L3, Ho2L3, Yb2L3, and Lu2L3 are structurally characterized by single crystal X-ray diffraction. In the Nd2L3 complex, both metals are 8 coordinate. Yb2L3, Tb2L3, Dy2L3, and Lu2L3 are isostructural. In these, as in the Gd2L3 and Ho2L3 complexes, one metal is 8 coordinate, one 7 coordinate. The ligand was found to have tunable emission in the solid state across the lanthanide series with a maximum at 556 nm for the Sm2L3 complex to 617 nm for Er2L3. Of these, most demonstrate only ligand-centered fluorescence at room temperature. The ligand was found to have much greater fluorescence in the complex Lu2L3. Here, we describe these distinctive triple decker complexes and their absorption and emission properties as both solids and solutions.

3.
Chem Commun (Camb) ; 53(42): 5718-5720, 2017 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-28487925

RESUMEN

The pentadentate coordination environment of a 2,6-bis[1-[(2-hydroxyphenyl)imino]ethyl] pyridine ligand scaffold was designed to accommodate the larger atomic radius of uranium as the uranyl dioxo cation, while fully occupying its equatorial plane. Here, two new uranyl (UO22+) complexes utilizing this scaffold have been synthesized from successive condensation reactions and subsequent metal complexation. Surprising Zn fluorescence is also discussed.

4.
Chem Commun (Camb) ; 53(88): 11984-11987, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29039852

RESUMEN

The synthesis, characterization, and electronic spectroscopy of two ML2 sandwich complexes, where M = Ce(iv) or Th(iv) and L = napthylsalophen2- are described. The ThL2 complex, unlike the isovalent CeL2, complex possesses unusual fluorescence properties in both solution and solid-state. These observations are explained with TD-DFT.

5.
Dalton Trans ; 45(36): 14243-51, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27535454

RESUMEN

Condensation of a 2,3-diaminophenazine or 2,3-diamino-2-quinoxalinol with two equivalents of 3,5-ditertbutylsalicylaldehyde affords new Schiff base ligands. Here, we describe and compare the synthesis, UV-Vis, electrochemical, solution, and solid state behaviour of the free base, salphenazine ligand [L(I)], and M[L(I)] complexes, where M = UO2(vi), Cu(ii), VO(iv), Zn(ii), Co(ii), and Ni(ii). The change in π-overlap and π-stacking between molecules and long-range ordering of the solid-state structure is vastly different depending on the size and electronic character of the metal. A sterically constrained µ-oxo Fe(iii) dimer complex is also reported.

6.
Dalton Trans ; 44(10): 4428-30, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25657039

RESUMEN

Metal templation by condensation of 2,3-diaminophenazine with 3,5-di-tert-butyl-2-hydroxybenzaldehyde around the metal centers [M = Cu(II), and UO2(VI)] affords a new class of M[di-tert-butyl salphenazine] metal complexes. Reported here is the synthesis, single crystal X-ray structural characterization, electronic spectroscopy, and microfluidic detection of the formation of these M[di-tert-butyl sal-phenazine] complexes.

7.
Rev Saude Publica ; 24(5): 387-93, 1990 Oct.
Artículo en Portugués | MEDLINE | ID: mdl-2101530

RESUMEN

The purpose of the study was the identification of risk factors for benign breast diseases (BBD); 257 women with BBD diagnosed through pathological anatomy or cytology and a matched control for each were studied. Subjects were selected at The State University of Campinas Hospital and at a private clinic. To enter the study cases had to have a first diagnosis of BBD between October 1979 and August 1984. The following BBD were considered: dysplasia, fibroadenoma, cystic disease, papilloma and ductal ectasia. Reproductive variables were studied as risk factors, including menstrual ovulatory cycles. The date on which the BBD was diagnosed was defined as the index date. For controls, data were considered up to when they had reached the same age as the matched case on the occasion of her diagnosis. Nulliparity was a risk factor for BBD. First birth at or above age 30 was a protective factor. Women who had used contraceptive pills for two or more years had a significantly lower risk than those who had never used them. The number of menstrual ovulatory cycles was not found to be associated with the risk of BBD. The results obtained from the study of Brazilian women confirm some of the conclusions found in the literature, mainly those that associate some reproductive variables with the risk of BBD. A few of these variables are also confirmed as risk factors for breast cancer.


PIP: This study identified risk factors for benign breast diseases (BBD) and 257 women with BBD diagnosed through pathological anatomy or cytology and a matched control for each were studied. Subjects were selected at the State University of Campinas Hospital, Brazil, and at a private clinic. To enter the study, cases were first diagnosed with BBD between October 1979-August 1984. The BBDs which were considered were: dysplasia, fibroadenoma, cystic disease, papilloma, and ductal ectasia. Reproductive variables were studied as risk factors and included menstrual ovulatory cycles. The date on which BBD was diagnosed was defined as the index date. For controls, data were considered up to when they had reached the same age as the matched case on the occasion of diagnosis. Nulliparity was a risk factor for BBD. First birth or age above 30 was a protective factor. Women who had used oral contraceptives for 2 or more years had a significantly lower risk than those who had never used them. The number of menstrual ovulatory cycles was not found to be associated with BBD risk. Results obtained from this study Brazilian women confirm some of the conclusions found in the literature, mainly those that associate some reproductive variables with the risk of BBD. A few of these variables are also confirmed as risk factors for breast cancer. (author's modified)


Asunto(s)
Enfermedades de la Mama/etiología , Brasil/epidemiología , Enfermedades de la Mama/epidemiología , Neoplasias de la Mama/genética , Estudios de Casos y Controles , Anticonceptivos Orales/efectos adversos , Femenino , Humanos , Menarquia , Menopausia , Paridad , Factores de Riesgo
8.
Rev Saude Publica ; 25(2): 96-102, 1991 Apr.
Artículo en Portugués | MEDLINE | ID: mdl-1784977

RESUMEN

A total of 2,364 women in marital union, 15 to 49 years of age, were interviewed at home. They lived in poor neighbourhoods in the metropolitan area and in the interior of S. Paulo State, Brazil. The prevalence of contraceptive pill use and the association between socio-demographic characteristics of users and the presence or not of risk factors for pill use were studied. One fourth (25.8 percent) of the women interviewed were using contraceptive pills. Prevalence was higher among younger women, those with no more than one live child and those who had completed between three and eight grades of schooling. Over 40 percent of the users referred having risk factors for pill use at the time they initiated the method. No association was found between age and the percentage of women with risk factors. This percentage increased with number of children and decreased with women's schooling. The fact that pills were prescribed or obtained through the health system was not associated with the proportion of users with risk factors. The percentage of users with risk factors was similar when comparing women who did not consult any health service before initiating use with those who had consulted a public service. The prevalence of use observed in this study is similar to that described by other authors. Results show that the health system in the State of S. Paulo played no role in the improvement in the prescription of hormonal contraceptive pills. Central policy seemed not to have filtered down to the peripheral areas of the system.


Asunto(s)
Anticonceptivos Orales/administración & dosificación , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos , Servicios de Salud para Mujeres
10.
Stud Fam Plann ; 14(11): 284-90, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6417842

RESUMEN

PIP: The basis for this report is home interviews of users of the contraceptive vaginal ring and the pill from urban and rural clinics in 2 provinces in the Dominican Republic and clinics from 2 towns and a large city in Brazil. Dominican ring users were significantly more likely to be older than pill users, to have more schooling, and have partners with more education. 6% were illiterate and 75% had only elementary education. 1/10 of the ring users reported having had problems with insertion of the ring and 1/5 had problems removing it. It may be worthwhile to try a narrower, more flexible model that may be easier to insert and remove. 1 out of every 6 users reported vaginal odor, 1 out of 8 reported having felt the ring move in their vagina, and 1/3 were aware of the ring at some time. About 1/2 the women in each country said the ring had changed color during use, and about 1/2 of those who reported the change did not like it. It became light gray and looked dirty. Correction may improve acceptance. 10% reported having expelled the ring. Twice as many ring users reported having menstrual problems. Ring and pill users both reported headaches, vaginal discharge, menstrual pain, and increased libido. A large proportion of ring and pill users experienced decreased duration and amount of menstrual bleeding, which was seen more as a beneficial than a negative effect. The same can be said for weight gain, which was "linked" by 89% of the women in the Dominican Republic. 64% of ring users and 67% of pill users described thier respective method as good or very good. Detailed instructions should accompany the final model. They should say that it is alright for the ring to be any place within tha vagina for it to be effective.^ieng


Asunto(s)
Conducta Anticonceptiva , Anticonceptivos Femeninos/administración & dosificación , Dispositivos Anticonceptivos/estadística & datos numéricos , Estradiol/administración & dosificación , Servicios de Planificación Familiar , Conocimientos, Actitudes y Práctica en Salud , Norgestrel/administración & dosificación , Adolescente , Adulto , Brasil , Anticonceptivos Femeninos/efectos adversos , Dispositivos Anticonceptivos/efectos adversos , Anticonceptivos Orales/administración & dosificación , Anticonceptivos Orales/efectos adversos , Anticonceptivos Orales Combinados/administración & dosificación , República Dominicana , Femenino , Humanos , Levonorgestrel , Elastómeros de Silicona , Encuestas y Cuestionarios
11.
IDRC Rep ; 13(2): 11, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12313242

RESUMEN

PIP: The vaginal contraceptive ring under development by the Population Council's International Committee on Contraceptive Research (ICCR) is 58 mm in diameter and consists of a core of Salastic covered by a thin layer of levonorgestrel and estradiol with an overcoat of silicone rubber. The ring is inserted on the 5th day of the menstrual cycle and withdrawn 3 weeks later for 1 week. The steroids are released from the Silastic and readily absorbed through the vagina. The blood levels of contraceptive hormones are sufficient to prevent ovulation but do not display the great daily variation commonly observed in women on oral contraceptive (OCs). The ring contains sufficient hormones for 6 months of contraception. Preliminary research in developed countries indicates that the ring is as effective as and safer than the pill. In order to determine whether a method requiring twice monthly handling of the genitals and carrying a foreign body in the vagina for 3 weeks at a time would prove acceptable to poorer periurban and rural women in developing countries, the International Development Research Centre supported a study of the ring's acceptability in actual practice in Santo Domingo, Dominican Republic, and Campinas, Brazil. The ring was offered, with other methods, in several clinics in each country where prescription, instructions, and follow-up were provided by paramedical personnel. 150-200 ring acceptors in each country were to be compared with pill users, who were chosen for comparative purposes because both methods are hormonal, require the same sequence of use and rest, and tend to induce regular menses. Ring users were slightly older than pill users and tended to be better educated. 10% of ring users complained of difficulty with insertion, 20% of difficulty with removal, 43% worried about correct placement despite being told that the ring would work however inserted, 33% reported vaginal pain, and 10% reported having expelled it at some time. About half the women said the ring had changed color and about 1/3 of them did not like the change. Twice as many ring as pill users reported menstrual problems but 26% of pill users compared to 17% of ring users reported other problems such as headaches. 42% of ring users and 62% of pill users reported gaining weight. 17% of ring users and 7% of pill users considered their experiences "very good" but the general level of satisfaction with both methods was similar. An earlier study indicated that women liked having control over use of the method, inserting and removing the ring at will for intercourse or washing. The decreased amount and duration of menstrual bleeding was welcomed by most users, as was weight gain by some users.^ieng


Asunto(s)
Conducta Anticonceptiva , Anticoncepción , Dispositivos Anticonceptivos Femeninos , Servicios de Planificación Familiar , Aceptación de la Atención de Salud , Investigación , Conducta Sexual , Américas , Brasil , Región del Caribe , Anticonceptivos Femeninos , Anticonceptivos Orales , Demografía , Países Desarrollados , Países en Desarrollo , República Dominicana , Economía , Fertilidad , América del Norte , Población , Dinámica Poblacional , América del Sur , Tecnología
12.
Bol Oficina Sanit Panam ; 115(2): 93-102, 1993 Aug.
Artículo en Español | MEDLINE | ID: mdl-8373536

RESUMEN

The purposes of the study were to identify reproductive risk factors for breast cancer and to test the hypothesis that reproductive variables operate through a common factor: the number of times that the mammary tissue has been exposed to the endocrine changes of the ovulatory cycle. The study was conducted in Campinas, and was based on interviews with 348 women with breast cancer first diagnosed between October 1979 and August 1984. The control group consisted of 348 women with healthy breasts. The data were obtained in interviews in the home, which were conducted using a structured questionnaire that had been pretested. The data were analyzed by calculation of the odds ratio, Mantel's statistic, to determine the linear trend; by Cornfield's method to calculate the confidence intervals; and by logistic regression adjusted for paired data. It was found that nulliparity, not having breast-fed, and a high number of menstrual cycles were significantly associated with the risk of presenting the disease. In the multivariate analysis, which included all the women, the only variable associated with the risk of mammary cancer was no history of breast-feeding. When the nulliparas were excluded, logistic regression showed that higher age of the woman at her first delivery was significantly associated with breast cancer.


Asunto(s)
Neoplasias de la Mama/epidemiología , Adulto , Brasil/epidemiología , Lactancia Materna/estadística & datos numéricos , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Edad Materna , Menopausia , Menstruación , Oportunidad Relativa , Paridad , Factores de Riesgo
15.
Rev. ginecol. obstet ; 1(3): 195-204, jul. 1990. tab
Artículo en Portugués | LILACS | ID: lil-106033

RESUMEN

Com objetivo de avaliar algumas das atividades desenvolvidas pelo Programa de Assistencia Integral a Saude da Mulher (PAISM), no Estado de Sao Paulo, foram entrevistadas em seus domicilios 3.703 mulheres de baixa renda com idade entre 15 e 49 anos: 2.021 na area metropolitana e 1.682 no interior. Este trabalho apresenta resultados referentes a adequacao do uso da laqueadura. Verificou-se que, de todas as mulheres entrevistadas, 17,9 por cento na area metropolitana e 25,9 por cento no interior estavam laqueadas. Constatou-se que a cirurgia foi realizada mais precocemente no interior que na area metropolitana (53 por cento comparada com 44 por cento na faixa de 20-29 anos de idade). A maioria das mulheres foi esterilizada por ocasiao de uma cesarea (72,2 por cento), pagou pela laqueadura (69,5 por cento) e combinou sua realizacao com o medico durante o pre-natal (86,9 por cento).


Asunto(s)
Servicios de Salud , Incidencia , Esterilización Tubaria , Brasil , Cesárea/efectos adversos
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