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951.
Lymphatic vessels surround follicles within the ovary, but their roles in folliculogenesis and pregnancy, as well as the necessity of lymphangiogenesis in follicle maturation and health, are undefined. We used systemic delivery of mF4-31C1, a specific antagonist vascular endothelial growth factor receptor 3 (VEGFR-3) antibody to block lymphangiogenesis in mice. VEGFR-3 neutralization for 2 weeks before mating blocked ovarian lymphangiogenesis at all stages of follicle maturation, most notably around corpora lutea, without significantly affecting follicular blood angiogenesis. The numbers of oocytes ovulated, fertilized, and implanted in the uterus were normal in these mice; however, pregnancies were unsuccessful because of retarded fetal growth and miscarriage. Fewer patent secondary follicles were isolated from treated ovaries, and isolated blastocysts exhibited reduced cell densities. Embryos from VEGFR-3–neutralized dams developed normally when transferred to untreated surrogates. Conversely, normal embryos transferred into mF4-31C1–treated dams led to the same fetal deficiencies observed with in situ gestation. Although no significant changes were measured in uterine blood or lymphatic vascular densities, VEGFR-3 neutralization reduced serum and ovarian estradiol concentrations during gestation. VEGFR-3–mediated lymphangiogenesis thus appears to modulate the folliculogenic microenvironment and may be necessary for maintenance of hormone levels during pregnancy; both of these are novel roles for the lymphatic vasculature.Ovarian neovascularization provides a unique environment in which to study physiological adult vasculogenesis apart from the traditional settings of wound healing and cancer pathologies. Lymphatic circulation plays a central role in fluid, lipid, and cellular transport,1 and lymphatic vessels are present within the ovary and surround follicles during development and maturation,2–5 but the importance of the lymphatic vasculature and lymphangiogenesis in the ovary is unclear. Consequently, the potential roles of lymphatic vessels in follicle maturation and pregnancy, and the extent of involvement or even necessity of maternal lymphangiogenesis in reproduction, are undefined. This contrasts with ovarian blood angiogenesis, whose critical roles in follicular nourishment and maturation and in the formation and maintenance of the corpus luteum are well appreciated; indeed, oocyte fertilization, embryonic implantation, uterine expansion, and successful gestation all require blood angiogenesis.6–8 Lymphangiogenesis, which is often concurrent with blood angiogenesis,9 may also play an important role in these processes.Adult blood angiogenesis requires signaling via vascular endothelial growth factor receptor 2 (VEGFR-2), most potently by VEGF ligation.10,11 In murine ovaries, VEGF expression increases during angiogenic growth phases,12 and blockade of VEGFR-2 signaling in mice effectively prevents angiogenesis, resulting in a marked decrease in ovarian weight, blood vessel density, and number of corpora lutea, and in infertility.13–15 Because gonadotropin treatment apparently does not correct these deficiencies,16 it is likely that follicle maturation and successful pregnancy are highly dependent on VEGFR-2–mediated neovascularization in the ovary.6,17 Vascularization also occurs in the uterine wall and decidua during pregnancy, and significant disruption of angiogenesis by VEGFR-2 blockade in these tissues after fertilization has been shown to greatly reduce pregnancy success.18VEGFR-3 is expressed primarily on lymphatic endothelial cells in adult tissue,19,20 and its signaling, via ligation by VEGF-C or VEGF-D, is necessary for lymphangiogenesis by inducing lymphatic endothelial cell proliferation and migration.19–23 Blockade of VEGFR-3 signaling using a function-blocking antibody such as mF4-31C1 (ImClone Systems; Eli Lilly, Indianapolis, IN) completely blocks the initiation of new lymphatic vessels in adult mice without affecting pre-existing lymphatic morphology or function and without apparently affecting blood angiogenesis.18,21,22 The ovary contains a dense lymphatic network that has been morphologically assessed in large rodents.24–26 Recent studies in which murine ovarian lymphatic vessel expansion was impaired during development found the dams to be infertile as adults.3We investigated VEGFR-3–mediated lymphangiogenesis and the roles of new lymphatic vessels and lymphangiogenesis in female reproduction and found that lymphangiogenesis occurs within the murine ovary during reproductive cycles and folliculogenesis and that VEGFR-3 neutralization prevents viable, full-term pregnancies. Using combined in vivo, ex vivo, and in vitro methods, we examined which aspects of female fertility are influenced by inhibited maternal lymphangiogenesis including oocyte and follicular development and maturation, uterine implantation, and embryonic development. After we had eliminated direct effects on fetal and uterine VEGFR-3–mediated neovascularization, our results suggested that the new ovarian lymphatic vessels specifically modulate follicle development and hormone production, demonstrating a critical and novel role for ovarian lymphangiogenesis in reproduction.  相似文献   
952.
Published data on the association between the transforming growth factor B1 (TGF‐B1) gene 509C/T polymorphism and gastric cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta‐analysis of the TGFB1‐509C/T polymorphism (with 2130 cases and 2374 controls) from seven published case‐control studies was performed. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the codominant model, the dominant model, and the recessive model. In the overall analysis, the T allele was significantly associated with susceptibility to gastric cancer in the recessive model (TT vs. CC+CT) (TT vs. CC+CT: OR = 1.35, 95% CI: 1.10–1.66, P = 0.10 for heterogeneity) when all the included studies were pooled into the meta‐analysis. In the stratified analysis by country, the T allele was also found to be significantly associated with increased gastric cancer risk in the recessive model (TT vs. CC+CT) in Chinese studies and in T versus C in the Indian study. In conclusion, this meta‐analysis supports the TGFB1‐509T polymorphism as a susceptibility factor for gastric cancer.  相似文献   
953.
ObjectiveClear cell sarcoma of the kidney (CCSK) is the second-most common but extremely rare primary renal malignancy in children after Wilms'' tumor. The aims of this study were to evaluate the imaging features that could distinguish between CCSK and Wilms'' tumor and to assess the features with diagnostic value for identifying CCSK.Materials and MethodsWe reviewed the initial contrast-enhanced abdominal-pelvic CT scans of children with CCSK and Wilms'' tumor between 2010 to 2019. Fifty-eight children (32 males and 26 females; age, 0.3–10 years), 7 with CCSK, and 51 with Wilms'' tumor, were included. The maximum tumor diameter, presence of engorged perinephric vessels, maximum density of the tumor (Tmax) of the enhancing solid portion, paraspinal muscle, contralateral renal vein density, and density ratios (Tmax/muscle and Tmax/vein) were analyzed on the renal parenchymal phase of contrast-enhanced CT. Fisher''s exact tests and Mann-Whitney U tests were conducted to analyze the categorical and continuous variables, respectively. Logistic regression and receiver operating characteristic curve analyses were also performed.ResultsThe age, sex, and tumor diameter did not differ between the two groups. Engorged perinephric vessels were more common in patients in the CCSK group (71% [5/7] vs. 16% [8/51], p = 0.005). Tmax (median, 148.0 vs. 111.0 Hounsfield unit, p = 0.004), Tmax/muscle (median, 2.64 vs. 1.67, p = 0.002), and Tmax/vein (median, 0.94 vs. 0.59, p = 0.002) were higher in the CCSK compared to the Wilms'' group. Multiple logistic regression revealed that engorged vessels (odds ratio 13.615; 95% confidence interval [CI], 1.770–104.730) and Tmax/muscle (odds ratio 5.881; 95% CI, 1.337–25.871) were significant predictors of CCSK. The cutoff values of Tmax/muscle (86% sensitivity, 77% specificity) and Tmax/vein (71% sensitivity, 86% specificity) for the diagnosis of CCSK were 1.97 and 0.76, respectively.ConclusionPerinephric vessel engorgement and greater tumor enhancement (Tmax/muscle > 1.97 or Tmax/vein > 0.76) are helpful for differentiating between CCSK and Wilms'' tumor in children aged below 10 years.  相似文献   
954.
ObjectiveTo evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters.Materials and MethodsA phantom, simulating the L2–4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings.ResultsThe skeletal muscle area (threshold, −29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30–150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0–44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used.ConclusionMeasurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.  相似文献   
955.
In 2011, human coxsackievirus B5 (CVB5) caused an outbreak of viral encephalitis in Henan, China. Complete genome sequence analysis based on two isolates showed that the 5′ half of the genome (nt 1-4540) had high similarity (>97 %) to that of CVB5 strain GU376747, and the 3′ half (nt 4700–7402) showed high similarity (>96 %) to that of human coxsackievirus B3 (CVB3) strain GQ141875. These isolates had the highest similarity (97.7 %) to the Changchun strain, based on the complete genome, rather than to other CVB5 strains isolated from Henan in recent years. There were therefore at least two groups of CVB5 circulating in Henan Province, which evolved at different rates.  相似文献   
956.
Adolescent idiopathic scoliosis (AIS) is a complex three dimensional spinal deformity which occurs mostly in prepubertal and pubertal girls. Although bracing and surgery have been the mainstays of treatment for AIS, because of the complications and poor compliance, many patients with this disorder continue to experience significant residual symptoms. The etiology and pathogenesis of AIS is unclear, but recent studies show the association between osteopenia and AIS and imply that osteopenia play a causative role in the development of AIS. Anti-osteoporosis treatment can improve bone strength, prevent osteoporosis and rebalance the OPG–RANK–RANKL system, which may help to prevent curve progression in AIS. This report proposes that anti-osteoporosis treatment may be an effective treatment for AIS.  相似文献   
957.
BackgroundRecent advances in respiratory management have improved survival for patients with Fukuyama congenital muscular dystrophy (FCMD), characterized by congenital muscular dystrophy and brain malformation. Previous studies reported that more than half of patients exhibit seizures in childhood. However, little is known about epilepsy after childhood.MethodsTo elucidate the long-term clinical course of epilepsy, we retrospectively reviewed all medical records in nine patients (6 males, mean age 20.7 years) with FCMD diagnosed between 1981 and 2019.ResultsThe follow-up periods ranged from 6 to 30 years (mean 18.4 years). A total of 75 EEG recordings were available from nine patients. In some patients, EEGs were normal during early childhood but tended to show paroxysmal discharges with age. Overall, epileptic seizures were observed in six patients. Except for one presenting with afebrile seizure at one year of age, the remaining five patients developed epilepsy between 13 and 22 years of age. The most common seizure type was focal impaired awareness seizure. After adolescence, four patients exhibited status epilepticus. Their convulsive movements of the seizures became less prominent with progression of the disease. At the last evaluation, most patients (5/6) had uncontrolled seizures.ConclusionsDespite presence of distinct brain malformation, epileptic seizures may develop after childhood in FCMD patients. Our experience suggests that clinicians should be careful not to overlook epileptic seizures, especially in advanced-stage patients who had profound muscle weakness.  相似文献   
958.
The aim of this study is to assess the association between crown-rump length (CRL) measured before the 10th gestational week and birth weight. Results from 316 transvaginal ultrasonography scans at the 46th, 53rd, 60th, 67th, and 74th days of pregnancy were compared in low birth weight (LBW) versus normal birth weight groups. A positive correlation between CRL and birth weight was observed when CRL was measured at days 60, 67, and 74. CRL measured on the 67th day of pregnancy was significantly smaller in the LBW group than in the normal birth weight group. A cut-off value of CRL=26.5 mm measured at day 67 has the highest power to predict LBW.  相似文献   
959.

Purpose

The aim of this study was to find an optimal range of activated clotting time (ACT) during off-pump coronary artery bypass surgery (OPCAB) yielding ischemic protection without the risk of hemorrhagic complications in patients with recent exposure to dual antiplatelet therapy.

Materials and Methods

Three hundred and five patients who received aspirin and clopidogrel within 7 days of isolated multi-vessel OPCAB were retrospectively studied. Combined hemorrhagic and ischemic outcome was defined as the occurrence of 1 of the following: significant perioperative bleeding (>30% of estimated blood volume), transfusion of packed red blood cell (pRBC) ≥2 U, or myocardial infarction (MI). This was compared in relation to the tertile distribution of the time-weighted average ACT-212-291 sec (first tertile), 292-334 sec (second tertile), 335-485 sec (third tertile).

Results

The amount of perioperative blood loss was 937±313 mL, 1014±340 mL, and 1076±383 mL, respectively (p=0.022). Significantly more patients in the third tertile developed MI (4%, 4%, and 12%, respectively, p=0.034). The incidence of significant perioperative blood loss and transfusion of pRBC ≥2 U were lower in the first tertile than those of other tertiles without statistical significance. In the multivariate analysis, the first tertile was associated with a 52% risk reduction of combined hemorrhagic and ischemic outcomes (95% confidence interval: 0.25-0.92, p=0.027).

Conclusion

A lower degree of anticoagulation with a reduced initial heparin loading dose should be carefully considered for patients undergoing OPCAB who have recently been exposed to clopidogrel.  相似文献   
960.

Purpose

The increasing prevalence and global spread of carbapenem-resistant Acinetobacter baumannii (A. baumannii) has become a serious problem. The aim of this study was to investigate molecular and epidemiological characteristics of carbapenem-resistant A. baumannii isolates collected from Korean non-tertiary hospitals.

Materials and Methods

Thirty six non-duplicated carbapenem-resistant A. baumannii isolates were collected from 17 non-tertiary hospitals in Korea between 2004 and 2006. Isolates were typed by multilocus sequence typing and repetitive-sequence-based PCR (rep-PCR). Detection of genes encoding OXA carbapenemase and their relationship with ISAba1 was performed by PCR.

Results

Two clones were prevalent among 36 isolates: ST69 (17 isolates, 47.2%) and ST92 (19 isolates, 52.8%). Rep-PCR patterns were diverse and revealed that all isolates were clustered into eight band patterns. The ISAba1-activated blaOXA-23-like and ISAba1-activated blaOXA-51-like genes were prevalent among the carbapenem-resistant A. baumannii isolates.

Conclusion

The class D β-lactamase genes of A. baumannii were distributed nationwide in non-tertiary Korean hospitals.  相似文献   
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