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1.
Hum Reprod ; 25(10): 2475-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20719814

RESUMO

BACKGROUND: The relationship between fibroids and infertility remains an unsolved question, and management of intramural fibroids is controversial. During the implantation phase, uterine peristalsis is dramatically reduced, which is thought to facilitate embryo implantation. Our aims were to evaluate (i) the occurrence and frequency of uterine peristalsis in infertile women with intramural fibroids and (ii) whether the presence of uterine peristalsis decreases the pregnancy rate. METHODS: Ninety-five infertile patients with uterine fibroids were examined using magnetic resonance imaging (MRI). Inclusion criteria were as follows: (i) presence of intramural fibroids, excluding submucosal type; (ii) no other significant infertility factors (excluding endometriosis); and (iii) regular menstrual cycles, and MRI performed at the time of implantation (luteal phase day 5-9). The frequency of junctional zone movement was evaluated using cine-mode-display MRI. After MRI, patients underwent infertility treatment for up to 4 months, and the pregnancy rate was evaluated prospectively. RESULTS: Fifty-one patients fulfilled the inclusion criteria, and 29 (57%) and 22 (43%) patients were assigned to the low (0 or 1 time/3 min) or high frequency (≥ 2 times/3 min) uterine peristalsis group, respectively. Endometriosis incidence was the same in both groups. Ten out of the 29 patients (34%) in the low-frequency group achieved pregnancy, compared with none of the 22 patients (0%) in the high-frequency group (P< 0.005). Comparing pregnant and non-pregnant cases, 4 of 10 patients (40%) and 9 of 41 patients (22%), respectively, had endometriosis (not significant). CONCLUSIONS: A higher frequency of uterine peristalsis during the mid-luteal phase might be one of the causes of infertility associated with intramural-type fibroids.


Assuntos
Infertilidade Feminina/etiologia , Leiomioma/fisiopatologia , Peristaltismo , Complicações Neoplásicas na Gravidez/fisiopatologia , Taxa de Gravidez , Neoplasias Uterinas/fisiopatologia , Adulto , Clomifeno/uso terapêutico , Endometriose/diagnóstico , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Infertilidade Feminina/tratamento farmacológico , Leiomioma/complicações , Imageamento por Ressonância Magnética , Menotropinas/uso terapêutico , Indução da Ovulação , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias Uterinas/complicações
2.
Org Lett ; 3(6): 921-4, 2001 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-11263916

RESUMO

It has been proposed that the origin of biological homochirality may be the result of irradiation of a racemic sample of amino acids by circularly polarized light (CPL). To determine the mechanism of enantiomeric enrichment, the irradiation of aliphatic amino acids by CPL was undertaken. An enantiomerically enriched sample (e.g., L isomer enrichment from r-CPL) was found to result from the preferential excitation/decomposition of one enantiomer over another via a Norrish Type II mechanism (leucine, valine, and isoleucine), with the enantiomeric excess dependent on the degree of protonation of the amino/carboxylic acid moiety.


Assuntos
Aminoácidos/química , Concentração de Íons de Hidrogênio , Leucina/química , Aminoácidos/efeitos da radiação , Dicroísmo Circular , Cinética , Leucina/efeitos da radiação , Conformação Molecular , Fotólise , Estereoisomerismo
3.
Appl Environ Microbiol ; 66(7): 2797-803, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10877770

RESUMO

The growth of marine bacteria under iron-limited conditions was investigated. Neither siderophore production nor bacterial growth was detected for Pelagiobacter sp. strain V0110 when Fe(III) was present in the culture medium at a concentration of <1.0 microM. However, the growth of V0110 was strongly stimulated by the presence of trace amounts of exogenous siderophore from an alpha proteobacterium, V0902, and 1 nM N-acyl-octanoylhomoserine lactone (C(8)-HSL), which is known as a quorum-sensing chemical signal. Even though the iron-binding functionality of a hydroxamate siderophore was undetected in the supernatant of V0902, a hydroxamate siderophore was detected in the supernatant of V0110 under the above conditions. These results indicated that hydroxamate siderophore biosynthesis by V0110 began in response to the exogenous siderophore from V0902 when in the presence of C(8)-HSL; however, C(8)-HSL production by V0110 and V0902 was not detected. Direct interaction between V0902 and V0110 through siderophore from V0902 was observed in the dialyzing culture. Similar stimulated growth by exogenous siderophore and HSL was also observed in other non-siderophore-producing bacteria isolated from marine sponges and seawater. The requirement of an exogenous siderophore and an HSL for heterologous siderophore production indicated the possibility that cell-cell communication between different species was occurring.


Assuntos
4-Butirolactona/análogos & derivados , Bactérias Gram-Negativas/crescimento & desenvolvimento , Ferro/metabolismo , Água do Mar/microbiologia , Sideróforos/farmacologia , 4-Butirolactona/química , 4-Butirolactona/metabolismo , 4-Butirolactona/farmacologia , Animais , Meios de Cultura/química , Diálise , Bactérias Gram-Negativas/metabolismo , Dados de Sequência Molecular , Poríferos/microbiologia , Sideróforos/metabolismo
4.
Bioorg Med Chem ; 7(9): 2073-81, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10530957

RESUMO

The mechanism of hemolysis and erythrocyte transformation caused by lipogrammistin-A (LGA), a lipophilic and acylated cyclic polyamine from the skin secretion of soapfishes (Grammistidae), was investigated. The dependency of hemolysis on the erythrocyte concentration indicated that the amount of membrane-bound LGA required for 50% hemolysis is about 13% of the total phospholipids in erythrocytes on a molar basis. A synthetic analogue which lacked a long alkyl chain exhibited much less activity, suggesting that the alkyl chain is important for membrane-binding. In addition, microscopic observations showed that LGA elicited the invagination of erythrocytes at sublytic concentrations, which makes LGA one of the most potent agents with this transforming activity known to date. Its protonated secondary amino group is responsible for the unequal distribution of LGA in the inner leaflet of the lipid bilayer, which leads to invagination, since acetylation at the amino group markedly reduced the invagination activity. Furthermore, the size of LGA-induced lesions on erythrocyte membrane was estimated to be 7-29 A based on osmotic protection experiments, where the external addition of isotonic molecules in this size range gradually increased the effective dose of LGA. Based on these lines of evidence, the mode of LGA action on erythrocytes is deduced to be as follows. First, LGA molecules bind to erythrocyte membrane by lipophilicity. Second, the molecules accumulate in the inner leaflet of the lipid bilayer by interaction of their cationic ammonium groups with acidic residues of membrane lipid in the inner surface. This uneven distribution of LGA distorts the bilayer structure, and results in a change in cell shape and consequent small lesions. Third, small solutes permeate through the lesions, which induces an osmotic change across the membrane, which leads to colloid-osmotic rupture. This mode of action of LGA on erythrocytes accompanied by cell invagination is the first reported example for natural defense substances.


Assuntos
Deformação Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Compostos Heterocíclicos/farmacologia , Pele/metabolismo , Animais , Peixes , Humanos , Análise Espectral , Termodinâmica
6.
J Synchrotron Radiat ; 5(Pt 3): 759-61, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15263644

RESUMO

A beamline which serves for calibrating transfer standard light sources (deuterium lamps, excimer lamps, Xe lamps etc.) in the UV and VUV regions is being constructed. The synchrotron radiation from the electron storage ring TERAS (750 MeV) is used as a primary standard of spectral radiant intensity. In order to use synchrotron radiation as a primary standard, the electron beam and synchrotron radiation beam parameters need to be evaluated. Uncertainties of synchrotron radiation flux evaluated by measurements of the magnetic flux density, the position of the electron orbital plane, the electron beam size and the distance from the synchrotron radiation tangent point to the detector system are expected to be about 0.003, 0.01, 0.05 and 0.1%, respectively.

7.
J Antibiot (Tokyo) ; 49(11): 1105-9, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8982339

RESUMO

Exophilin A, a new antibacterial compound, was discovered in the culture of the marine microorganism Exophiala pisciphila NI10102, which was isolated from a marine sponge Mycale adhaerens. The absolute chemical structure of exophilin A was elucidated as a trimer of (3R,5R)-3,5-dihydroxydecanoic acid by spectroscopic methods and analyses of a degradative product. Exophilin A showed antimicrobial activity against Gram-positive bacteria.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/química , Antibacterianos/farmacologia , Decanoatos/química , Decanoatos/isolamento & purificação , Decanoatos/farmacologia , Fermentação , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana
8.
Appl Opt ; 29(31): 4538-40, 1990 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20577425

RESUMO

Measurement and calculation of the polarization properties of an evaporated Al mirror as a retardation plate of a VUV polarimeter are presented.

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