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101.
Peter S. Heyl William M. Sappenfield Deborah Burch Leticia E. Hernandez Victoria M. Kavanaugh Washington C. Hill 《Maternal and child health journal》2013,17(7):1230-1235
This report presents findings from two state-based pregnancy-related reviews of deaths due to pulmonary embolism to describe prevalence, risk factors, and timing of symptoms and fatal events (N = 46). We examined the utility of state-based maternal mortality review teams as a means to gain more complete data on maternal deaths from which guidelines for prevention and intervention can be developed. The Florida Pregnancy-Associated Mortality Review Team and Virginia Maternal Mortality Review Team collaborated on findings from 9 years of pregnancy-related mortality review conducted in each state. Pregnancy-related deaths due to pulmonary embolism occurring within 42 days of pregnancy between 1999 and 2007 in Florida and Virginia were identified. Retrospective review of records was conducted to obtain data on timing of the fatal event in relation to the pregnancy, risk factors, and the presence and timing of symptoms suggestive of pulmonary embolism. Forty-six cases of pregnancy-related death due to pulmonary embolism were identified. The combined pregnancy-related mortality ratio (PRMR) was 1.6/100,000 live births. The PRMR for patients undergoing cesarean section delivery was 2.8 compared to 0.2 among those with vaginal deliveries (95 % CI = 1.8–4.2 and 0.1–0.5 respectively). Women aged 35 and older had the highest PRMR at 2.6/100,000 live births. BMI over 30 kg/m2 and presence of chronic conditions were frequently identified risk factors. One in five decedents (21.7 %) reported at least two symptoms suggestive of pulmonary embolism in the days before death. This combined state-based maternal death review confirms age over 35 years, obesity, and the presence of chronic conditions are risk factors for pregnancy-related mortality due to venous thromboembolism in the US. Expanding and standardizing the process of state-based reviews offers the potential for reducing pregnancy-related mortality in the US. 相似文献
102.
Joan Chang Monica M Nicolau Thomas R Cox Daniel Wetterskog John WM Martens Holly E Barker Janine T Erler 《Breast cancer research : BCR》2013,15(4):R67
Introduction
Lysyl oxidase-like 2 (LOXL2) is a matrix-remodeling enzyme that has been shown to play a key role in invasion and metastasis of breast carcinoma cells. However, very little is known about its role in normal tissue homeostasis. Here, we investigated the effects of LOXL2 expression in normal mammary epithelial cells to gain insight into how LOXL2 mediates cancer progression.Methods
LOXL2 was expressed in MCF10A normal human mammary epithelial cells. The 3D acinar morphogenesis of these cells was assessed, as well as the ability of the cells to form branching structures on extracellular matrix (ECM)-coated surfaces. Transwell-invasion assays were used to assess the invasive properties of the cells. Clinically relevant inhibitors of ErbB2, lapatinib and Herceptin (traztuzumab), were used to investigate the role of ErbB2 signaling in this model. A retrospective study on a previously published breast cancer patient dataset was carried out by using Disease Specific Genomic Analysis (DSGA) to investigate the correlation of LOXL2 mRNA expression level with metastasis and survival of ErbB2-positive breast cancer patients.Results
Fluorescence staining of the acini revealed increased proliferation, decreased apoptosis, and disrupted polarity, leading to abnormal lumen formation in response to LOXL2 expression in MCF10A cells. When plated onto ECM, the LOXL2-expressing cells formed branching structures and displayed increased invasion. We noted that LOXL2 induced ErbB2 activation through reactive oxygen species (ROS) production, and ErbB2 inhibition by using Herceptin or lapatinib abrogated the effects of LOXL2 on MCF10A cells. Finally, we found LOXL2 expression to be correlated with decreased overall survival and metastasis-free survival in breast cancer patients with ErbB2-positive tumors.Conclusions
These findings suggest that LOXL2 expression in normal epithelial cells can induce abnormal changes that resemble oncogenic transformation and cancer progression, and that these effects are driven by LOXL2-mediated activation of ErbB2. LOXL2 may also be a beneficial marker for breast cancer patients that could benefit most from anti-ErbB2 therapy. 相似文献103.
Oliver Kumpf Evangelos J Giamarellos-Bourboulis Alexander Koch Lutz Hamann Maria Mouktaroudi Djin-Ye Oh Eicke Latz Eva Lorenz David A Schwartz Bart Ferwerda Christina Routsi Chryssanthi Skalioti Bart-Jan Kullberg Jos WM van der Meer Peter M Schlag Mihai G Netea Kai Zacharowski Ralf R Schumann 《Critical care (London, England)》2010,14(3):1-11
Introduction
Severe sepsis is a disease of the microcirculation, with endothelial dysfunction playing a key role in its pathogenesis and subsequent associated mortality. Angiogenesis in damaged small vessels may ameliorate this dysfunction. The aim of the study was to determine whether the angiogenic factors (vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), fibroblast growth factor (FGF), and angiopoietin-1 (Ang-1) and -2 (Ang-2)) are mortality indicators in Malawian children with severe bacterial infection.Methods
In 293 children with severe bacterial infection, plasma VEGF, PDGF, FGF, and Ang-1 and Ang-2 were measured on admission; in 50 of the children with meningitis, VEGF, PDGF, and FGF were also measured in the CSF. Healthy controls comprised children from some of the villages of the index cases. Univariable and multivariable logistic regression analyses were performed to develop a prognostic model.Results
The median age was 2.4 years, and the IQR, 0.7 to 6.0 years. There were 211 children with bacterial meningitis (72%) and 82 (28%) with pneumonia, and 154 (53%) children were HIV infected. Mean VEGF, PDGF, and FGF concentrations were higher in survivors than in nonsurvivors, but only PDGF remained significantly increased in multivariate analysis (P = 0.007). Mean Ang-1 was significantly increased, and Ang-2 was significantly decreased in survivors compared with nonsurvivors (6,000 versus 3,900 pg/ml, P = 0.03; and 7,700 versus 11,900 pg/ml, P = 0.02, respectively). With a logistic regression model and controlling for confounding factors, only female sex (OR, 3.95; 95% CI, 1.33 to 11.76) and low Ang-1 (OR, 0.23; 95% CI, 0.08 to 0.69) were significantly associated with mortality. In children with bacterial meningitis, mean CSF VEGF, PDGF, and FGF concentrations were higher than paired plasma concentrations, and mean CSF, VEGF, and FGF concentrations were higher in nonsurvivors than in survivors (P = 0.02 and 0.001, respectively).Conclusions
Lower plasma VEGF, PDGF, FGF, and Ang-1 concentrations and higher Ang-2 concentrations are associated with an unfavorable outcome in children with severe bacterial infection. These angiogenic factors may be important in the endothelial dysregulation seen in severe bacterial infection, and they could be used as biomarkers for the early identification of patients at risk of a poor outcome. 相似文献104.
Teresa WM Fan Andrew N Lane Richard M Higashi Mohamed A Farag Hong Gao Michael Bousamra Donald M Miller 《Molecular cancer》2009,8(1):41-19
Background
Metabolic perturbations arising from malignant transformation have not been systematically characterized in human lung cancers in situ. Stable isotope resolved metabolomic analysis (SIRM) enables functional analysis of gene dysregulations in lung cancer. To this purpose, metabolic changes were investigated by infusing uniformly labeled 13C-glucose into human lung cancer patients, followed by resection and processing of paired non-cancerous lung and non small cell carcinoma tissues. NMR and GC-MS were used for 13C-isotopomer-based metabolomic analysis of the extracts of tissues and blood plasma. 相似文献105.
106.
107.
From 1985-1987, a total of 34 couples undergoing superovulation for a
single in-vitro fertilization (IVF) cycle with clomiphene citrate and
purified follicle stimulating hormone (FSH) or human menopausal
gonadotrophin (HMG) were randomly allocated doses of intra-nasal buserelin
to induce an endogenous gonadotrophin surge, prior to oocyte collection.
The doses ranged from a single 25 microg dose to 100 microg every 4 h for
20 h. In three cycles the treatment was abandoned because of a poor ovarian
response. In the remaining 31 cycles buserelin was given to induce the
endogenous gonadotrophin surge, but there was evidence of premature
luteinization in eight cycles and a premature gonadotrophin surge in four
cycles. Although a single dose as low as 40 microg induced a surge and
resulted in a pregnancy, a single dose of 50 microg proved the most
effective minimal dose consistently to induce a gonadotrophin surge and
oocyte maturation. Recent reports using gonadotrophin-releasing hormone
(GnRH) analogues to induce a gonadotrophin surge has prompted publication
of this previously unpublished data.
相似文献
108.
Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro 总被引:1,自引:0,他引:1
The study investigates the correlation between oocyte maturity and
fertilization and a variety of hormonal parameters in follicular fluid and
ovarian granulosa cells. A methodology for purification of granulosa cells
from contaminating blood cells is also established. A total of 63
follicular aspirates were collected at oocyte retrieval from 30 women
superovulated using the long luteinizing hormone- releasing hormone (LHRH
analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone,
testosterone and human chorionic gonadotrophin (HCG) were quantified in
follicular fluid and granulosa cells were immunostained for human chorionic
gonadotrophin. Immunopurification of granulosa cells from contaminating
blood cells was performed. HCG in follicular fluid was significantly high
in follicles yielding immature (grade 3) oocytes (P=0.002); there was no
correlation with fertilization. Aspirates from follicles containing mature
(grade 1) oocytes and oocytes that subsequently fertilized had
significantly more granulosa cells immunobound to HCG (P < 0.001,
P=0.02). Moreover, the immunomagnetic purification technique provided
>98% pure population of granulosa cells. The data demonstrate that HCG
in follicular fluid and on granulosa cells may help to predict oocyte
maturity and fertilization. Furthermore, immunomagnetic beads provide a
reliable procedure for the purification of ovarian granulosa cells.
相似文献
109.
目的:探讨中药保元强肾Ⅱ号胶囊对慢性肾功能衰竭(CRF)的疗效及机理。方法:60例CRF患者随机分为保元强肾Ⅱ号胶囊加洛汀新组(治疗组,30例)及必需氨基酸加洛汀新组(对照组,30例),观察肾功能及肾小管标志蛋白的改变。结果:治疗组显效率及总有效率分别为633%及933%;对照组分别为300%及567%,治疗组疗效明显优于对照组(P<001);治疗组治疗后BUN、SCr及CCr均较治前明显改善,尿视黄醇结合蛋白、尿β2微球蛋白及尿N乙酰氨基葡萄糖苷酶均比治疗前显著降低,TammHorfau蛋白比治疗前显著增高(P<001或P<005)。结论:保元强肾Ⅱ号胶囊对肾小管间质损伤有明显的改善作用,从而改善肾功能,提高疗效。 相似文献
110.
Meldrum A Thomson W Drummond B Sears M 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2001,11(6):458-458
The aim of the present study was to clinically evaluate fissure sealants on the occlusal fissures and buccal pits of permanent first and second molars after 20 and 15 years, respectively. The population consisted of 72 children, each of whom had had their four first molars sealed between 1977 and 1980. At the annual examinations, all caries-free, newly erupted second molars were sealed. When sealant was applied to the second molars, the first molars were checked and sealant was reapplied to those that had deficient sealants. At the follow-up, when the subjects were 26–27 years of age, 27 in the original group had moved from the community. Thus, the present result is based on 45 subjects. One hundred and fifty-three sealed first molars and 161 sealed second molars were available for inspection. At the follow-up examination of the first molars 20 years after sealant had been applied, 65% showed complete retention, 22% partial retention without caries, and 1306 caries or restoration in the occlusal fissures or buccal pits. At the 15-year follow-up of the second molars, the corresponding figures were 65%, 30% and 5%, respectively. Of the restored or carious molars, significantly more were found in the mandible than in the maxilla ( P < 0.001). This longitudinal study showed that pit and fissure sealants, applied during childhood, have a long-lasting, caries-preventive effect. 相似文献