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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 149: 788-92, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-25989616

RESUMO

Glasses of lithium fluoroborate of the composition LiF 15%-B2O3 85% with increasing CuO as added dopant were prepared and characterized by combined optical and FTIR spectroscopy before and after gamma irradiation. The optical spectrum of the undoped glass reveals strong UV absorption with two distinct peaks at about 235 and 310 nm and with no visible bands. This strong UV absorption is related to the presence of unavoidable trace iron impurity (Fe(3+)) within the materials used for the preparation of this glass. After irradiation, the spectrum of the undoped glass shows a decrease of the intensity of the UV bands together with the resolution of an induced visible broad band centered at about 520 nm. The CuO doped glasses reveal the same UV absorption beside a very broad visible band centered at 780 nm and this band shows extension and splitting to several component peaks with higher CuO contents. Upon gamma irradiation, the spectra of all CuO-doped glasses reveal pronounced decrease of their intensities. The response of irradiation on the studied glasses is correlated with suggested photochemical reactions together with some shielding effect of the copper ions. The observed visible band is related to the presence of copper as distorted octahedral Cu(2+) ions. Infrared absorption spectra of the prepared glasses show repetitive characteristic triangular and tetrahedral borate units similar to that published from alkali or alkaline earth oxides B2O3 glasses. A suggested formation of (BO3/2F) tetrahedral units is advanced through action of LiF on B2O3 and these suggested units showing the same position and number as BO4 tetrahedra.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 131: 497-501, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24840491

RESUMO

Combined optical and infrared absorption spectra of V2O5-doped cadmium borate glasses were investigated before and after gamma irradiation with a dose of 8 Mrad (=8×10(4) Gy). The undoped base cadmium borate glass reveals a spectrum consisting of strong charge transfer UV absorption bands which are related to the presence of unavoidable contaminated trace iron impurities (mainly Fe(3+)). The V2O5-doped glasses reveal an extra band at 380nm and the high V2O5-content glass also shows a further band at about 420nm. The observed optical spectrum indicates the presence of vanadium ions mainly in the pentavalent state (d(0) configuration). The surplus band at 420nm shows that some trivalent vanadium ions are identified at high V2O5 content. The optical spectra of the glasses after gamma irradiation show small decrease of the intensity of the UV absorption which are interpreted by assuming the transformation of some Fe(3+) ions by photochemical reactions with the presence of high content (45mol%) of heavy massive CdO causing some shielding behavior. FT infrared absorption spectra of the glasses show vibrational bands due to collective presence of triangular and tetrahedral borate groups in their specific wavenumbers. The FTIR spectra are observed to be slightly affected by both the V2O5-dopants being present in modifying low percent or gamma irradiation due to the presence of high content heavy CdO.


Assuntos
Boratos/química , Cádmio/química , Vidro/química , Vanádio/análise , Raios gama , Vidro/efeitos da radiação , Íons/análise , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Compostos de Vanádio/análise
3.
Hum Reprod ; 17(7): 1767-72, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12093837

RESUMO

BACKGROUND: The study aim was to determine whether moulding the embryo transfer catheter according to the uterocervical angle measured by ultrasound could improve pregnancy and implantation rates. METHODS: Patients were alternately allocated to one of two groups. In the ultrasound-guided group (n = 320), the catheter was moulded according to the uterocervical angle measured by abdominal ultrasound. In controls (n = 320), embryo transfer was performed using the "clinical feel" method. RESULTS: Moulding the embryo transfer catheter according to the uterocervical angle significantly increased clinical pregnancy [(OR = 1.57, 95% CI (1.08-2.27)] and implantation rates [(OR = 1.47, 95% CI (1.10-1.96)] compared with the "clinical feel" method. It also significantly reduced difficult transfers [(OR = 0.25, 95% CI (0.16-0.40)] and blood during transfers [OR = 0.71, 95% CI (0.50-0.99)]. Patients with large angles (>60 degrees ) had significantly lower pregnancy rates compared with those with no angle [OR = 0.36, 95% CI (0.16-0.52)]. CONCLUSIONS: Moulding the embryo transfer catheter according to the uterocervical angle measured by ultrasound increases clinical pregnancy and implantation rates and diminishes the incidence of difficult and bloody transfers.


Assuntos
Colo do Útero/diagnóstico por imagem , Transferência Embrionária , Útero/diagnóstico por imagem , Cateterismo , Implantação do Embrião , Transferência Embrionária/efeitos adversos , Transferência Embrionária/instrumentação , Desenho de Equipamento , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Ultrassonografia , Hemorragia Uterina/etiologia , Hemorragia Uterina/prevenção & controle
4.
Hum Reprod ; 16(2): 272-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11157819

RESUMO

A modified hypo-osmotic solution was used to select viable ejaculated and testicular spermatozoa to perform intracytoplasmic sperm injection (ICSI) in 27 treatment cycles from patients with total absence of sperm motility. The treatment cycles consisted of 15 cycles in which ejaculated spermatozoa were used and 12 cycles in which testicular spermatozoa were used. The hypo-osmotic solution consisted of 50% culture medium and 50% deionized water and was shown in previous in-vitro studies to be superior to the original solution used in the classical hypo-osmotic swelling test. Fertilization was achieved in 37.3% of the oocytes injected. Embryos were replaced in 70.4% of the cycles with a mean of 2.0 embryos per cycle. There were no statistically significant differences between the ejaculated sperm group and the testicular sperm group in the fertilization rate (42.7 versus 30.1%) or in the cleavage rate (92.7 versus 77.3%). Four pregnancies resulted, two in the ejaculated sperm group and two in the testicular sperm group, a pregnancy rate of 14.8%. All pregnancies were singletons but one pregnancy in each group had an early miscarriage. There were no statistically significant differences between both groups in the pregnancy rates (13.3 versus 16.7%), in the implantation rates (5.3 versus 11.8%) or in the delivery/ongoing pregnancy rates (6.7 versus 8.3%). It is concluded that the use of this solution to select viable but immotile spermatozoa for ICSI is a simple and practical method and is associated with acceptable fertilization and pregnancy rates.


Assuntos
Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas , Espermatozoides/patologia , Adulto , Separação Celular/métodos , Sobrevivência Celular , Ejaculação , Feminino , Humanos , Soluções Hipotônicas , Masculino , Pessoa de Meia-Idade , Pressão Osmótica , Gravidez , Motilidade dos Espermatozoides , Testículo/patologia
5.
Int J Fertil Womens Med ; 45(4): 285-91, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10997485

RESUMO

OBJECTIVE: To determine the minimal requirements for achieving a full-term singleton pregnancy in hMG-treated patients. METHODS: One hundred and ninety-two pregnancy cycles resulting from hMG therapy in infertile patients were retrospectively studied to determine the minimal requirements for the occurrence of a pregnancy in those women. The cycles were divided into five groups: pregnancies ending in miscarriage, ectopic pregnancies, pregnancies ending in preterm delivery, full-term singleton pregnancies, and full-term multiple pregnancies. The number of hMG ampules, the number of preovulatory follicles reaching 18 mm or more in diameter, the cervical mucus score (Insler), the number of living spermatozoa per high-power field (HPF) observed in the cervical mucus on the day of hCG administration, and the midluteal plasma progesterone concentration were determined and correlated with the outcome of the pregnancy in the five groups studied. The minimal requirements for the occurrence of a full-term singleton pregnancy were also determined. RESULTS: In this cohort of 192 women, the mean number of hMG ampules administered was 25.38 (1903.5 IU), the mean number of preovulatory follicles reaching 18 mm was 2.1, the mean cervical mucus score (Insler) was 9.48, and the mean number of motile spermatozoa per HPF in the cervical mucus on the day of hCG administration was 19.3. There were no statistically significant differences between the five groups studied regarding these four variables. The mean midluteal plasma progesterone concentration was 29.07 ng/mL and there was no statistically significant difference in midluteal plasma progesterone concentration between the cycles resulting in full-term deliveries and those ending in miscarriage. However, a statistically significant difference in midluteal plasma progesterone concentration was found between the cycles resulting in full-term singleton pregnancies and those resulting in full-term multiple pregnancies. CONCLUSIONS: The minimal requirements for achieving a full-term singleton pregnancy were 9 ampules of hMG (675 IU), one 18-mm follicle, a cervical mucus score (Insler) of 6 on the day of hCG administration, and a midluteal plasma progesterone concentration of 10.83 ng/mL. The presence of motile spermatozoa in the cervical mucus was a reassuring sign in 92.7% of instances but was not an absolute necessity for a successful outcome.


Assuntos
Anovulação/tratamento farmacológico , Infertilidade Feminina/tratamento farmacológico , Menotropinas/uso terapêutico , Resultado da Gravidez , Análise de Variância , Muco do Colo Uterino/citologia , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Fase Folicular/efeitos dos fármacos , Humanos , Infertilidade Feminina/sangue , Fase Luteal/sangue , Fase Luteal/efeitos dos fármacos , Menotropinas/administração & dosagem , Menotropinas/sangue , Gravidez , Progesterona/sangue , Estudos Retrospectivos , Contagem de Espermatozoides
6.
Fertil Steril ; 71(4): 711-4, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10202883

RESUMO

OBJECTIVE: To determine reference values for the midluteal plasma progesterone concentration. DESIGN: Retrospective analysis. SETTING: Infertility clinic at an academic medical center. PATIENT(S): One hundred ninety-two infertile women who became pregnant after induction of ovulation with hMG. INTERVENTION(S): The plasma progesterone level was measured during the midluteal phase of the hMG treatment cycle. MAIN OUTCOME MEASURE(S): The midluteal plasma progesterone concentration was correlated with the outcome of the pregnancy. RESULT(S): In this cohort of 192 women in whom ovulation was induced with hMG and 5,000 IU of hCG, the mean midluteal plasma progesterone concentrations were 29.07 ng/mL, 25.85 ng/mL, 31.49 ng/mL, 41.39 ng/mL, and 28.64 ng/mL in all cycles that resulted in pregnancy, cycles that resulted in full-term singleton pregnancy, cycles that resulted in full-term multiple pregnancy, cycles that resulted in preterm pregnancy, and cycles that ended in miscarriage, respectively. There was no statistically significant difference in the progesterone concentration between the cycles that resulted in full-term pregnancy and those that ended in miscarriage, but there was a statistically significant difference between the cycles that resulted in singleton pregnancy and those that resulted in multiple pregnancy. The minimum value that was compatible with a full-term pregnancy in this cohort of women was 10.83 ng/mL. CONCLUSION(S): In a cohort of 192 women, the minimum plasma progesterone concentration on day 7 in women who attained a full-term pregnancy after induction of ovulation with 5,000 IU of hCG was 10.83 ng/mL.


Assuntos
Infertilidade Feminina/terapia , Fase Luteal , Menotropinas/uso terapêutico , Indução da Ovulação/métodos , Resultado da Gravidez , Progesterona/sangue , Aborto Espontâneo/sangue , Feminino , Idade Gestacional , Humanos , Gravidez , Gravidez Ectópica/sangue , Gravidez Múltipla/sangue , Valores de Referência , Estudos Retrospectivos
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