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41.
Human immunodeficiency virus (HIV-1) enters target cells by binding its gp120 exterior envelope glycoprotein to CD4 and one of the chemokine receptors, CCR5 or CXCR4. CD4-induced (CD4i) antibodies bind gp120 more efficiently after CD4 binding and block the interaction with the chemokine receptor. Examples of CD4i antibodies are limited, and the prototypes of the CD4i antibodies exhibit only weak neutralizing activity against primary, clinical HIV-1 isolates. Here we report the identification of a novel antibody, E51, that exhibits CD4-induced binding to gp120 and neutralizes primary HIV-1 more efficiently than the prototypic CD4i antibodies. The E51 antibody blocks the interaction of gp120-CD4 complexes with CCR5 and binds to a highly conserved, basic gp120 element composed of the beta 19-strand and surrounding structures. Thus, on primary HIV-1 isolates, this gp120 region, which has been previously implicated in chemokine receptor binding, is accessible to a subset of CD4i antibodies.  相似文献   
42.
Even though entirely digitized microscopic tissue sections (whole slide images, WSIs) are increasingly being used in histopathology diagnostics, little data is still available on the effect of this technique on pathologists' reading time. This study aimed to compare the time required to perform the microscopic assessment by pathologists between a conventional workflow (an optical microscope) and digitized WSIs. WSI was used in primary diagnostics at the Laboratory for Pathology Eastern Netherlands for several years (LabPON, Hengelo, The Netherlands). Cases were read either in a traditional workflow, with the pathologist recording the time required for diagnostics and reporting, or entirely digitally. Reading times were extracted from image management system log files, and the digitized workflow was fully integrated into the laboratory information system. The digital workflow saved time in the majority of case categories, with prostate biopsies saving the most (68% time gain). Taking into account case distribution, the digital workflow produced an average gain of 12.3%. Using WSI instead of conventional microscopy significantly reduces pathologists' reading times. Pathologists must work in a fully integrated environment to fully reap the benefits of a digital workflow.  相似文献   
43.
44.

Objectives

To review the maternal and fetal outcome of triplet, quadruplet and quintuplet gestations following ART, which were managed at a hospital over 11 years.

Study design

Retrospective chart review of 150 triplet, 27 quadruplet, and 6 quintuplet pregnancies between January 2001 and December 2011. 25 women aged 50–56 years with triplet pregnancies, were excluded due to lack of data. No prophylactic interventions were used.

Results

300 triplets, 108 quadruplets, and 30 quintuplets were born. The mean maternal age was 30.2 years (SD 4.2 years). Mean gestational age delivery was 32.2 weeks (SD 4.2 weeks). Maternal complications included preterm labor 114 (86 %), prematurity 115 (87 %), anemia 44 (33 %) gestational diabetes 35 (27 %), preeclampsia 33 (25 %), post partum hemorrhage 13 (10 %). Preterm labor was diagnosed in 84 (84 %) triplets, 32 (97 %) of quadru- and quintuplet pregnancies (P > 0.05). Prematurity and preterm labor were major determinants. Of the 438 fetuses born there were 57 (13 %) still births, 77 (18 %) neonatal deaths. 32 (7 %) were early neonatal deaths, 45 (10 %) late neonatal deaths. The majority died due to extreme low birth weight. 75 (17 %) neonates had low apgar score of <7 at 5 min. 22 (5 %) infants had congenital anomalies. Severe respiratory distress syndrome, perinatal asphyxia, very early preterm delivery and perinatal mortality were higher in quadru- and quintuplets (P < 0.05).

Conclusion

Preterm labor and preterm prematurity were the commonest complications. Neonatal mortality and morbidity was significantly increased in quadru- and quintuplets. Prophylactic interventions were not used in an attempt to prevent preterm labor.  相似文献   
45.
46.
Drowning is a leading cause of accidental injury and death in young children. Anoxic brain injury (ABI) is a common consequence of drowning and can cause severe neurological morbidity in survivors. Assessment of functional status and prognostication in drowning victims can be extremely challenging, both acutely and chronically. Structural neuroimaging modalities (CT and MRI) have been of limited clinical value. Here, we tested the utility of resting‐state functional MRI (rs‐fMRI) for assessing brain functional integrity in this population. Eleven children with chronic, spastic quadriplegia due to drowning‐induced ABI were investigated. All were comatose immediately after the injury and gradually regained consciousness, but with varying ability to communicate their cognitive state. Eleven neurotypical children matched for age and gender formed the control group. Resting‐state fMRI and co‐registered T1‐weighted anatomical MRI were acquired at night during drug‐aided sleep. Network integrity was quantified by independent components analysis (ICA), at both group‐ and per‐subject levels. Functional‐status assessments based on in‐home observations were provided by families and caregivers. Motor ICNs were grossly compromised in ABI patients both group‐wise and individually, concordant with their prominent motor deficits. Striking preservations of perceptual and cognitive ICNs were observed, and the degree of network preservation correlated (ρ = 0.74) with the per‐subject functional status assessments. Collectively, our findings indicate that rs‐fMRI has promise for assessing brain functional integrity in ABI and, potentially, in other disorders. Furthermore, our observations suggest that the severe motor deficits observed in this population can mask relatively intact perceptual and cognitive capabilities. Hum Brain Mapp 38:4813–4831, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
47.
48.
Death with a functioning graft and death‐censored renal allograft failure remain major problems for which effective preventative protocols are lacking. The retrospective cohort study aimed to determine whether histologic changes on a 5‐year surveillance kidney biopsy predict adverse outcomes after transplantation in recipients who had: both Type 2 diabetes (T2DM) and obesity (BMI ≥ 30 kg/m2) at the time of transplantation (T2DM/Obesity, n = 75); neither (No T2DM/No obesity, n = 78); No T2DM/Obesity (n = 41), and T2DM/No obesity (n = 47). On 5‐year biopsies, moderate‐to‐severe mesangial expansion was more common in the T2DM/Obesity group (Banff mm score ≥2 = 49.3%; Tervaert classification MS ≥ 2b = 26.7%) compared to the other groups (p < .001 for both scores). Risk factors included older age, higher BMI, HbA1C, and triglycerides at 1‐year post‐transplant. Moderate‐to‐severe mesangial expansion correlated with death with function (HR 1.74 (1.01, 2.98), p = .045 Banff and 1.89 (1.01, 3.51) p = .045 Tervaert) and with death‐censored graft loss (HR 3.2 (1.2, 8.8), p = .02 Banff and HR 3.8 (1.3, 11.5), p = .01 Tervaert) over a mean of 11.6 years of recipient follow‐up post‐transplant. These data suggest that mesangial expansion in recipients with T2DM and obesity may reflect systemic vascular injury and might be a novel biomarker to predict adverse outcomes post renal transplant.  相似文献   
49.
Annals of Surgical Oncology - Breast cancer-related lymphedema (BCRL) is a source of postoperative morbidity for breast cancer survivors. Lymphatic microsurgical preventive healing approach...  相似文献   
50.
Experimental allergic encephalomyelitis (EAE) is characterized by inflammatory infiltrates of myelin antigen(s) specific T cells and consecutive demyelination. Injection of encephalitogen into the footpads induces disease in genetically susceptible Dark Agouti rats (DA) but not in Albino Oxford (AO) rats although mild inflammatory infiltrates are observed in both strains early after disease induction. In addition, only DA rats develop disease when cells from (AO×DA) F(1) hybrids are passively transferred into sub-lethally radiated AO and DA parent hosts. The aim of the study was therefore to examine the participation of accessory cells, macrophages, dendritic cells and microglia in EAE development at the level of the target tissue in these two strains using specific membrane markers. We demonstrate here that in the induction phase of EAE in DA rats, macrophages (CD68(+); CD45(hi)CD11b(+)) are the first detectable infiltrating cells in the subpial regions of the spinal cord but were not found in AO rats. During the same period, resident microglial cells which are of the ramified variety are observed in both DA and AO rats. In DA rats at the peak of disease, when profuse influx of T cells is seen, macrophages and dendritic cells appear in the parenchyma of the CNS. In addition, at that time, microglial cells are activated. FACS analyses also reveal a significant increase in CD45(hi)CD11c(+) dendritic cells and CD45(hi)D11b(+) macrophages compared with levels in na?ve and immunized AO rats. During resolution of disease in DA rats, the expression of microglia and macrophage markers is comparable with those in na?ve non-immunized DA and immunized AO rats. We conclude that an initial influx of macrophages is indispensible for the development of EAE in DA rats. The presence of dendritic cells and myeloid dendritic cells at the peak of disease supports the role of these cells in EAE especially in relapses and chronicity. The activation pattern of microglia in DA rats does not indicate their role as antigen presenting cells in disease induction since they are ramified at the induction phase and only become activated after the overwhelming influx of T cells.  相似文献   
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