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81.
Conclusions: In patients with total sudden sensorineural hearing loss (SSNHL), oral prednisone (OP) alone or intratympanic dexamethasone (ITD) alone have comparable results. The addition of salvage ITD following OP does not seem to add over either single modality treatment. Objectives: To study the effect of steroid-based treatments in patients with total SSNHL. Methods: The medical charts of 59 patients with total loss of hearing, defined as pure tone thresholds in the profound range (> 90 dB) with an unobtainable speech reception threshold (SRT) that were treated with OP (n = 20), ITD (n = 13), or OP followed by salvage ITD (n = 26) were analyzed. Response to treatment was evaluated by means of pure tone thresholds, SRT, and speech discrimination score (SDS), immediately after treatment and on a follow-up visit. Results: Forty-nine patients (83%) responded to treatment, with mean significant improvements of 36, 34, 31, and 25 dB at 500, 1000, 2000, and 4000 Hz, respectively. The mean improvement in SRT was 33 dB, and SDS improved by 32%. There were no differences in improvement in pure tone thresholds and SRT among the three treatment groups. The late effect of OP was similar to the effect of salvage ITD.  相似文献   
82.
Purpose

Does thawing cleavage embryos and culturing them for transfer as blastocysts improve pregnancy and perinatal outcomes compared to transferring thawed blastocysts?

Methods

Retrospective, observational cohort study performed at two assisted reproductive technology centers, 2014 to 2020. A total of 450 patients with 463 thawed embryo transfer cycles were divided into 2 groups according to the embryonic developmental stage at cryopreservation and transfer: 231 thawed blastocysts (day 5 group) and 232 thawed cleavage embryos that were cultured for 2 days and transferred as blastocysts (day 3–5 group). The two groups were compared for demographics, routine parameters of IVF treatment, pregnancy rates, and perinatal outcomes.

Results

Multivariable logistic regression analysis for ongoing pregnancy and delivery demonstrated that the day 3–5 group had a greater likelihood of achieving ongoing pregnancy and delivery compared to the day 5 group (OR 1.58, 95%CI 1.062–2.361, p?=?0.024). Perinatal outcomes were comparable between the three groups.

Conclusion

Our results support culturing post-thaw cleavage embryos for 2 days and transferring them as blastocysts to increase chances of ongoing pregnancy and delivery.

  相似文献   
83.
84.
Neuroblastoma is a heterogeneous neoplasm that has served as a paradigm for the clinical utility of somatically acquired genomic aberrations. DNA copy number alterations (CNA) are currently used to predict prognosis, including MYCN amplification and deletions at chromosome bands 1p36 and 11q23. We predicted that genome-wide assessment of DNA aberrations in neuroblastoma tumors would provide a more precise estimation of clinical phenotype, and could be used to predict outcome. We measured CNAs in a representative set of 82 diagnostic tumors on a customized high-resolution BAC array-based CGH platform supplemented with additional clones across 1p36, 2p24, 3p21-22, 11q14-24, and 16p12-13, and integrated these data with RNA expression data. We used an unbiased statistical method to define a set of minimal common regions (MCRs) of aberration. Unsupervised hierarchical clustering identified four distinct genomic subclasses. First, a subset of tumors with a clinically benign phenotype showed predominantly whole chromosome gains and losses. Second, tumors with MYCN amplification had a unique genomic signature of 1p deletion and 17q gain, but few other rearrangements. Third, tumors with an aggressive clinical phenotype without MYCN amplification, showed multiple structural rearrangements. Most notable were deletions of 3p, 4p, and 11q and gain of 1q, 2p, 12q, and 17q. Lastly, there was a subset of tumors with an aggressive clinical phenotype and no detectable DNA CNAs. The genomic subsets were highly correlated with patient outcome, and individual MCRs remained prognostic in a multivariable model. DNA signature patterns embed important prognostic information in diagnostic neuroblastoma samples, and can identify candidate cancer-related genes.  相似文献   
85.
Apolipoprotein E4 (APOE4) genotype is the strongest genetic risk factor for late-onset Alzheimer disease and confers a proinflammatory, neurotoxic phenotype to microglia. Here, we tested the hypothesis that bone marrow cell APOE genotype modulates pathological progression in experimental Alzheimer disease. We performed bone marrow transplants (BMT) from green fluorescent protein–expressing human APOE3/3 or APOE4/4 donor mice into lethally irradiated 5-month-old APPswe/PS1ΔE9 mice. Eight months later, APOE4/4 BMT–recipient APPswe/PS1ΔE9 mice had significantly impaired spatial working memory and increased detergent-soluble and plaque Aβ compared with APOE3/3 BMT–recipient APPswe/PS1ΔE9 mice. BMT-derived microglia engraftment was significantly reduced in APOE4/4 recipients, who also had correspondingly less cerebral apoE. Gene expression analysis in cerebral cortex of APOE3/3 BMT recipients showed reduced expression of tumor necrosis factor-α and macrophage migration inhibitory factor (both neurotoxic cytokines) and elevated immunomodulatory IL-10 expression in APOE3/3 recipients compared with those that received APOE4/4 bone marrow. This was not due to detectable APOE-specific differences in expression of microglial major histocompatibility complex class II, C-C chemokine receptor (CCR) type 1, CCR2, CX3C chemokine receptor 1 (CX3CR1), or C5a anaphylatoxin chemotactic receptor (C5aR). Together, these findings suggest that BMT-derived APOE3-expressing cells are superior to those that express APOE4 in their ability to mitigate the behavioral and neuropathological changes in experimental Alzheimer disease.Humans uniquely have three different apolipoprotein E (APOE) alleles (ɛ2, ɛ3, and ɛ4). APOE4 is the single greatest genetic risk factor for late-onset Alzheimer disease (AD), and there is a gene dosage effect.1 However, genetic association does not inform function/pathogenesis. Multiple mechanisms have been postulated that predominantly focus on production, metabolism, or clearance of amyloid-β (Aβ) and that are variably supported by multiple observations, including: i) APOE genotype is strongly related to Aβ levels in brain and cerebrospinal fluid of AD patients2,3; ii) modulation of apolipoprotein E (apoE) protein levels in brain results in alterations of Aβ burden4,5; iii) Aβ degradation is at least partially apoE dependent6,7; and iv) Aβ clearance is differentially modulated by apoE isoforms, with APOE4 mice exhibiting reduced central and peripheral Aβ clearance compared with APOE3 mice.8–10 Aβ degradation and clearance is at least partially dependent on microglia, the innate immune effector cells of the brain. Microglia have migratory and phagocytic capacity, are increased in the vicinity of Aβ plaques, and phagocytose Aβ.11–13 APOE genotype modulates central nervous system innate immune function in culture,14 including astrocyte and microglia elaboration of cytokines and chemokines,15,16 microglia production of reactive oxygen species,17 microglia-mediated paracrine neurotoxicity,18 microglia migration,19 and other functions.20 However, the specific contribution of microglial APOE genotype to AD pathophysiology in vivo is largely unknown.To address this critical question and to test a potential therapeutic application, we used the fact that bone marrow transplantation (BMT) results in the gradual replacement of endogenous (host) microglia (to the near exclusion of other cell types) with microglia derived from donor marrow, in both wild-type mice and transgenic mouse models of AD.21–24 We used targeted-replacement (TR) APOE mice homozygous for either the APOE3 or APOE4 gene inserted into the mouse APOE regulatory elements25,26 that coexpressed green fluorescent protein (GFP). We transplanted whole bone marrow (BM) isolated from TR APOE3/3;GFP or TR APOE4/4;GFP mice into lethally irradiated APPswe/PS1ΔE9 mice to determine the specific role of microglial APOE genotype in the pathological progression of AD.  相似文献   
86.
Bone tissue engineering is an alternative approach to bone grafts. In our study we aim to develop a composite scaffold for bone regeneration made of doped zirconium oxide (ZrO2) conjugated with poly(lactic-co-glycolic acid) (PLGA) particles for the delivery of growth factors. In this composite, the PLGA microspheres are designed to release a crucial growth factor for bone formation, bone morphogenetic protein-2 (BMP2). We found that by changing the polymer’s molecular weight and composition, we could control microsphere loading, release and size. The BMP2 released from PLGA microspheres retained its biological activity and increased osteoblastic marker expression in human mesenchymal stem cells (hMSCs). Uncapped PLGA microspheres were conjugated to ZrO2 scaffolds using carbodiimide chemistry, and the composite scaffold was shown to support hMSCs growth. We also demonstrated that human umbilical vein endothelial cells (HUVECs) can be co-cultured with hMSCs on the ZrO2 scaffold for future vascularization of the scaffold. The ZrO2 composite scaffold could serve as a bone substitute for bone grafting applications with the added ability of releasing different growth factors needed for bone regeneration.  相似文献   
87.
No data exist on biologic differences between Cancer of unknown primary (CUP) and metastatic solid tumors of known primary site. We assigned a primary tissue of origin in 40 favorable CUP patients (A: serous peritoneal carcinomatosis n = 14, B: axillary adenocarcinoma n = 8, C: upper squamous cervical adenopathy n = 18) by means of a 64-microRNA assay. Subsequently, we profiled the expression of 733 microRNAs (miRs) in the CUP cases and compared results with metastases from 20 ovarian carcinomas, 10 breast adenocarcinomas, 20 squamous head neck or lung tumors. In the Peritoneal CUP versus Ovarian (Known Primary Metastases) KPM comparison, a total of 12 miR were significantly differentially expressed: higher than twofold expression difference in CUP was seen only for miR-513a-5p (3.7-fold upregulated) and miR-483-5p (2.5-fold upregulated), while miR-708 exhibited a twofold downregulation. In the Breast CUP versus Breast KPM comparison, only miR-29c that were downregulated in CUP by 2.7-fold satisfied the FDR threshold. miR-30e and miR-27b, downregulated in ovarian CUPs versus KPMs, were also non-significantly downregulated in breast CUP by 2.0- and 1.4-fold respectively. Six miRs, which belong to the 17–92 oncocluster showed a trend of upregulation in Breast CUP versus Breast KPM cases. A CUP signature remains elusive.  相似文献   
88.
The main aim of this study is to evaluate the relationship between depression and immunological function in parents of children with cancer. Thirty-two parents participated in the study. The parents completed the following assessments: a list of major stressful events in a Hemato-Oncology ward, beck depression inventory II (BDI-II), posttraumatic diagnostic scale (PDS) and quality of life (QOL) questionnaire. A single blood sample was drawn from parents for evaluation of cortisol levels and lymphocyte cell subgroups. The parents were divided into two groups: Those who suffered from depression as defined by BDI-II cutoff score of 14 (depressed parents (DP), n = 7), and non-depressed parents (non-DP, n = 25). In parents of children with cancer the DP group had statistically significantly higher stressful event scores, dysfunction scores (from the PDS) and CD8 percentage compared to the non-DP group. QOL, CD4 percentage and CD4/CD8 ratio were significantly lower in the DP group. The BDI scores significantly positively correlated with events and dysfunctional scores, and significantly negatively correlated with QOL scores and CD4/CD8 ratio. High psychiatric morbidity was found in parents of children with cancer. The findings of altered immunity in DP provide further evidence that the physiological response to stress and depression may alter immune functions.  相似文献   
89.
Parents of children with disabilities vary in their reaction to their children's diagnosis. The current study focused on fathers in addition to mothers and examined their resolution and coping styles when having children diagnosed with developmental delay (DD). Sixty-five fathers and 71 mothers were interviewed using the reaction to the diagnosis interview (RDI; Pianta & Marvin, 1992a). Results indicated that the majority of parents were unresolved with their child's diagnosis, with no differences found between fathers’ and mothers’ rates of resolution. Furthermore, both parents of children that were diagnosed at a later age and parents that were less educated tended to be unresolved, as did fathers of a lower socioeconomic status. Older age of both children and mothers was related to maternal lack of resolution. Finally, an in-depth examination revealed significant differences in the manner in which fathers and mothers cope with their children's diagnosis: whereas mothers were more prone to using an emotional coping style, fathers tended to use a cognitive coping style. The clinical implications of paternal versus maternal coping styles are discussed.  相似文献   
90.
Objective.?The objective of this study was to examine the rate of respiratory morbidity in neonates delivered by elective cesarean delivery (ECD) at term, with a definite confirmation of gestational age (GA) by 1st-trimester ultrasound.

Methods.?Consecutive women carrying a singleton pregnancy and undergoing ECD at term (>38 1/7 weeks), confirmed by 1st-trimester ultrasound, were included in the study group. Multiple gestations, cesarean section (CS) in labor, CS performed after rupture of membranes and induced deliveries were excluded. The control group included women with a singleton pregnancy at term (>38 1/7 weeks) who delivered spontaneously. This group of women was randomly selected during the study period.

Results.?The study group included 277 women delivered by ECD. The control group consisted of 311 women. Five newborns in the study group and none in the control group were admitted to the neonatal intensive care unit (NICU) due to respiratory disorders (p < 0.02). Excluding diabetic women did not change the results. On multivariate analysis, no other factors were found to independently influence the risk of respiratory complications.

Conclusion.?In our study, the rate of respiratory morbidity was found to be significantly higher in neonates delivered by ECD compared to those delivered vaginally. The fact that GA was confirmed by 1st-trimester ultrasound makes iatrogenic prematurity an unlikely sole cause for this excess morbidity.  相似文献   
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