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81.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
82.
The patterns of exochorion ornaments on eggs of seven South American Lutzomyia sand fly species were analyzed by scanning electron microscopy (SEM): Lutzomyia (Lutzomyia) cruzi (Mangabeira 1938), Lutzomyia (Micropygomyia) evandroi (Costa Lima and Antunes 1936), L. (Nyssomyia) intermedia (Lutz and Neiva 1912), L. longipalpis (Lutz and Neiva 1912), L. migonei (Franca 1920), L. (Nyssomyia) neivai (Pinto 1926), and L. renei (Martins, Falcao, and Silva 1957). Different patterns were observed, which showed the distinction between some species. Egg ornaments in L. cruzi and L. longipalpis appear as single, parallel, unconnected ridges, whereas eggs of L. migonei appear as single, parallel, connected ridges. Eggs of L. (Nyssomyia) intermedia and L. (N.) neivai present a new variation of the single, unconnected, parallel ridges pattern: small tubercles are present, distributed between the ridges. Eggs of L. renei present an elliptical pattern, with most structures connected by straight ridges. Eggs of L. (M.) evandroi present a polygonal pattern, with alternate rows of small and large hexagons. Our data emphasize the advantages of the SEM approach in the study of the exochorion patterns of Lutzomyia eggs and in the distinction of the sand fly species. 相似文献
83.
Dosimetry measurements and Monte Carlo simulations for a catheter-based 32P endovascular brachytherapy source wire are described. The measured dose rates were obtained using both radiochromic dye film and an automated plastic scintillator. The investigated source has dimensions of 27 mm in length and 0.24 mm in diameter, and is encapsulated in NiTi. For the radiochromic film measurements, calibrated radiochromic dye film was irradiated at distances between 1 and 5 mm from the source axis in A-150 plastic, and read out with a high-resolution scanning densitometer. The depth-dose curve measured in A-150 is then converted to that in water using correction factors obtained from Monte Carlo calculations. For the scintillator system, direct measurements in water were acquired at distances between 1 and 6 mm from the center of the source, along the perpendicular bisector of the source axis. The scintillator was calibrated in terms of absorbed-dose rate in a reference beta-particle field at multiple depths. The measured dose rates obtained from the film and scintillator measurements were then normalized to the measured source activity, i.e., to convert the measured data to units of cGy/s/mCi. Theoretical dosimetry calculations of the catheter-based 32P wire geometry were also obtained from Monte Carlo simulations using the Electron Gamma Shower code (EGS4), the Monte Carlo N-particle transport code (MCNP4B), and CYLTRAN from the Integrated Tiger Series codes (ITS v.3) and found to be in good agreement. The results of both measurements and calculations are expressed as absorbed-dose rate in water per unit of contained activity (cGy/s/mCi). Comparisons indicate that the measured and calculated dosimetry are in good agreement (<10%) within the relevant treatment distances (1-5 mm). This work fully characterizes the radiation field around a novel 32P beta brachytherapy source in water. The depth-dose curve can be used to calculate the dose to the vessel wall from a 27 mm 32P source wire centered within the vessel lumen. 相似文献
84.
Barbosa SE Dujardin JP Soares RP Pires HH Margonari C Romanha AJ Panzera F Linardi PM Duque-De-Melo M Pimenta PF Pereira MH Diotaiuti L 《Journal of medical entomology》2003,40(4):411-420
Comparisons were made among Panstrongylus megistus (Burmeister) from three areas of Brazil (Bahia, Minas Gerais, and Santa Catarina), where populations differ with regard to their degree of association with human dwellings. The following characters were studied: morphology of the eggs and the male genitalia; morphometry of the head and thorax; isoenzyme profile; enzymatic activity of the alpha-glycerophosphate dehydrogenase (alpha-GPDH); and cytogenetics. In general, differences were observed in the weight, diameter, and length of the egg among Bahia, Minas Gerais, and Santa Catarina populations. Differences were not observed in the architecture of the egg exochorion. The size of the median process of the pygophore of the male genitalia of individuals from Bahia differed from the other two populations. The Minas Gerais population presented the largest number of denticles in the endosome process. The morphometry of the head and thorax differentiated Santa Catarina from the Bahia and Minas Gerais populations. Phosphoglucomutase (EC 5.4.2.2., PGM) was the only enzyme out of 11 that showed polymorphism; the population from Minas Gerais was most polymorphic, whereas the population from Santa Catarina was monomorphic. Study of the alpha-GPDH activity and cytogenetics did not reveal differences among the three populations. Analysis of all the characters studied together with information on these three populations from previous publications allowed a phenogram to be constructed. Two distinct groups were evident, one represented by Santa Catarina and the other by Bahia and Minas Gerais. Considering the greater variability of the Minas Gerais and Bahia populations, we propose the inclusion of these states within the area of origin of P. megistus. 相似文献
85.
Grimmond S Van Hateren N Siggers P Arkell R Larder R Soares MB de Fatima Bonaldo M Smith L Tymowska-Lalanne Z Wells C Greenfield A 《Human molecular genetics》2000,9(10):1553-1560
The mammalian sex-determining pathway is controlled by the presence or absence of SRY expression in the embryonic gonad. Expression of SRY in males is believed to initiate a pathway of gene expression resulting in testis development. In the absence of SRY, ovary development ensues. Several genes have now been placed in this pathway but our understanding of it is far from complete and several functional classes of protein appear to be absent. Sex-determining genes frequently exhibit sexually dimorphic patterns of expression in the developing gonad both before and after overt differentiation of the testis or ovary. In order to identify additional sex-determining or gonadal differentiation genes we have examined gene expression in the developing gonads of the mouse using cDNA microarrays constructed from a normalized urogenital ridge library. We screened for genes exhibiting sexually dimorphic patterns of expression in the gonad at 12.5 and 13.5 days post-coitum, after overt gonad differentiation, by comparing complex cDNA probes derived from male and female gonadal tissue at these stages on micro-arrays. Using in situ hybridization analysis we show here that two genes identified by this screen, protease nexin-1 (Pn-1) and vanin-1 (Vnn1), exhibit male-specific expression prior to overt gonadal differentiation and are detected in the somatic portion of the developing gonad, suggesting a possible direct link to the testis-determining pathway for both genes. 相似文献
86.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
87.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
88.
Yasmin Amaral Leila Silva Fernanda Soares Daniele Marano Sylvia Nehab Andrea Abranches Ana Carolina Costa Maria Elisabeth Moreira 《Nutrients》2021,13(5)
Background: To evaluate the potential factors associated with the nutritional composition of human milk of puerperal women. Methods: cross-sectional study, conducted between March 2016 and August 2017, with 107 women, selected in a Tertiary Health Care Tertiary Health Facility of the Unified Health System (SUS) in the Municipality of Rio de Janeiro. Data were collected two months after delivery. The dependent variable of the study was the nutritional composition of human milk. We divided the independent variables into hierarchical levels: distal (age, schooling, parity and pregestational nutritional status), intermediate (number of prenatal visits and gestational weight gain) and proximal (alcohol consumption, smoking, diabetes mellitus and hypertension). For data analysis, we applied the multiple linear regression, centered on the hierarchical model. Only the variables associated with the nutritional composition of breast milk remained in the final model at a 5% level of significance. Results: The nutritional composition of human milk yielded by women with pregestational overweight, smokers and hypertensive had higher amounts of lipids and energy. Conversely, women with gestational weight gain below the recommended had lower amounts of these components. Conclusion: The evaluation of factors associated with the nutritional composition of human milk is extremely important to assist post-partum care practices. In this study, we observed that lipid and energy contents were associated to pregestational nutritional status, gestational weight gain, smoking and hypertension. 相似文献
89.
Markus Walther Victor Valderrabano Martin Wiewiorski Federico Giuseppe Usuelli Martinus Richter Tiago Soares Baumfeld Johanna Kubosch Oliver Gottschalk Udo Wittmann 《Foot and Ankle Surgery》2021,27(3):236-245
BackgroundThe aim of this study is to systematically review the literature on clinical outcomes of patients who have undergone autologous matrix-induced chondrogenesis (AMIC) for treatment of osteochondral lesions of the talus (OCL) and compare the studies’ outcomes.MethodsPubmed and Embase were searched in January 2020 for articles concerning OCL surgery. Studies were included if they had a minimum 1-year follow-up and the primary measures were functional outcomes. The meta-analysis compared the Visual Analogic Score (VAS), the American Orthopedic Foot and Ankle Score (AOFAS), and the Foot Function Index (FFI) between baseline and follow-up of 1?2 years, and 3?5 years. A random effects model was used to evaluate outcome changes.ResultsThe search returned 15 studies, with a total of 492 patients. The VAS improved 4.45 and 4.6 points from baseline to the 1?2 year and 3?5 year follow-up, respectively (p < 0.001). AOFAS improved 31.59 and 32.47 points from baseline to the 1?2 year and 3?5 year follow-up, respectively (p < 0.001). The FFI showed a significant improvement of 30.93 points from baseline to year 3?5 (p < 0.001). A total of 6 patients with revision surgeries have been reported within the follow up period. It was not possible to correlate clinical features like lesion size, surgical approach, and bone marrow stimulation technique to the reported outcome.ConclusionSurgical treatment of OCL via the AMIC procedure provided significant improvement in the functional outcome and pain scores when compared to the pre-operative values. Improvements were observed up to 5 years post-operatively. 相似文献
90.
Sérgio Soares Tiago Mota Gomes Gustavo Campos Filipe Medeiros João Bragança Xavier Martin Oliva 《Foot and Ankle Surgery》2021,27(5):567-576
BackgroundVascular injury after hallux valgus surgery is a rare condition but serious complications can ensue.MethodsWe performed an anatomical study using 26 cadaveric lower extremities. We enhanced first metatarsal bone’s (FMB) vascularization by injecting latex. Each specimen was classified according to the severity of hallux valgus deformity (HVD). Then we measured two distances: one between the first tarsometatarsal joint (FTMJ) to the first dorsal branch’s origin, the other between the first metatarsophalangeal joint (MTP) to the dorsal plexus’s origin.ResultsThe distance between the FTMJ and the first dorsal branch to the FMB ranges from 10 mm in normal feet to 15 mm in severe deformed feet. The distance between the MTP and the dorsal plexus’ origin ranges from 20 mm in normal feet to 25 mm in severe deformed feet.ConclusionsUnderstanding the foot’s vascular anatomy has allowed us to adapt surgical landmarks to the severity of the HVD and to avoid post-operative complications. 相似文献