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81.
82.
We studied the lymphoid tissue biopsies of 20 patients with chronic human immunodeficiency virus (HIV) infection by analyzing collagen deposition, CD4+ cell number, and gene expression of metalloproteinases (MMPs; MMP-2, MMP-9) and tissue inhibitors of MMPs (TIMPs; TIMP-1, TIMP-2). HIV-infected patients had significantly increased collagen deposition (P = .001), fewer CD4+ T cells (P = .05), and decreased MMP-9/TIMP-1 and MMP-2/TIMP-2 ratios (P = .01), compared with HIV-negative control patients. Moreover, we found a significant negative correlation between collagen deposition and the MMP-9/TIMP-1 ratio (ρ = -0.50; P = .047). To our knowledge, this is the first time that MMP/TIMP imbalance has been correlated with lymphoid tissue collagen deposition and incomplete immune recovery in HIV-infected patients, even after long-term antiretroviral treatment.  相似文献   
83.
Epilepsy is a common finding in chromosomal imbalances, but only a few chromosome abnormalities have a characteristic electro-clinical pattern. Trisomy X is one of the most common sex chromosome abnormalities in females, and is associated with considerable phenotypic variability. This report describes four 47,XXX females with mental deficiency and epilepsy. Although a specific electro-clinical pattern could not be defined, the epileptic phenotypes of these patients share many features; we suggest that the association 47,XXX/epilepsy/mental retardation may not be coincidental. This report also enlarges the clinical spectrum of the 47,XXX phenotype. Moreover, these observations highlight the critical role of chromosome X in epilepsy and mental retardation.  相似文献   
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85.
Purpose : To follow plasma Flt3-ligand (FL) concentrations in irradiated animals in order to evaluate it as an indicator of bone marrow damage for the management of accidental radiation-induced aplasia. Materials and methods : Non-human primates were irradiated at doses ranging from 2 to 8 Gy, using whole- or partial-body irradiation. Plasma FL concentrations and blood cell counts were determined daily. Results : FL concentrations increased as early as day 2 after irradiation, whatever the irradiation dose. Increase in plasma FL concentration on day 5 post-irradiation was correlated with radiation dose and with the severity of radiation-induced aplasia. During the course of aplasia, FL concentrations in plasma were inversely correlated with neutrophil counts. A peak in FL concentration appeared before the neutrophil nadir, and the subsequent decrease in FL concentration was correlated with the recovery of blood-cell populations. Conclusions : Monitoring plasma FL concentration can be used as an indicator of radiation-induced marrow aplasia, and this may be of use in accidental irradiation situations.  相似文献   
86.
The fetal heart rate (FHR) is a marker of fetal well-being in utero (when monitoring maternal and/or fetal pathologies) and during labor. Here, we developed a smart mobile data module for the remote acquisition and transmission (via a Wi-Fi or 4G connection) of FHR recordings, together with a web-based viewer for displaying the FHR datasets on a computer, smartphone or tablet. In order to define the features required by users, we modelled the fetal monitoring procedure (in home and hospital settings) via semi-structured interviews with midwives and obstetricians. Using this information, we developed a mobile data transfer module based on a Raspberry Pi. When connected to a standalone fetal monitor, the module acquires the FHR signal and sends it (via a Wi-Fi or a 3G/4G mobile internet connection) to a secure server within our hospital information system. The archived, digitized signal data are linked to the patient’s electronic medical records. An HTML5/JavaScript web viewer converts the digitized FHR data into easily readable and interpretable graphs for viewing on a computer (running Windows, Linux or MacOS) or a mobile device (running Android, iOS or Windows Phone OS). The data can be viewed in real time or offline. The application includes tools required for correct interpretation of the data (signal loss calculation, scale adjustment, and precise measurements of the signal’s characteristics). We performed a proof-of-concept case study of the transmission, reception and visualization of FHR data for a pregnant woman at 30 weeks of amenorrhea. She was hospitalized in the pregnancy assessment unit and FHR data were acquired three times a day with a Philips Avalon® FM30 fetal monitor. The prototype (Raspberry Pi) was connected to the fetal monitor’s RS232 port. The emission and reception of prerecorded signals were tested and the web server correctly received the signals, and the FHR recording was visualized in real time on a computer, a tablet and smartphones (running Android and iOS) via the web viewer. This process did not perturb the hospital’s computer network. There was no data delay or loss during a 60-min test. The web viewer was tested successfully in the various usage situations. The system was as user-friendly as expected, and enabled rapid, secure archiving. We have developed a system for the acquisition, transmission, recording and visualization of RCF data. Healthcare professionals can view the FHR data remotely on their computer, tablet or smartphone. Integration of FHR data into a hospital information system enables optimal, secure, long-term data archiving.  相似文献   
87.

Introduction

Few markers are available that can predict response to tamoxifen treatment in estrogen receptor (ER)-positive breast cancers. Identification of such markers would be clinically useful. We attempted to identify molecular markers associated with tamoxifen failure in breast cancer.

Methods

Eighteen initially ER-positive patients treated with tamoxifen requiring salvage surgery (tamoxifen failure [TF] patients) were compared with 17 patients who were disease free 5 years after surgery plus tamoxifen adjuvant therapy (control patients). cDNA microarray, real-time quantitative PCR, and immunohistochemistry on tissue microarrays were used to generate and confirm a gene signature associated with tamoxifen failure. An independent series of 33 breast tumor samples from patients who relapsed (n = 14) or did not relapse (n = 19) under tamoxifen treatment from a different geographic location was subsequently used to explore the gene expression signature identified.

Results

Using a screening set of 18 tumor samples (from eight control patients and 10 TF patients), a 47-gene signature discriminating between TF and control samples was identified using cDNA arrays. In addition to ESR1/ERα, the top-ranked genes selected by statistical cross-analyses were MET, FOS, SNCG, IGFBP4, and BCL2, which were subsequently validated in a larger set of tumor samples (from 17 control patients and 18 TF patients). Confirmation at the protein level by tissue microarray immunohistochemistry was observed for ER-α, γ-synuclein, and insulin-like growth factor binding protein 4 proteins in the 35 original samples. In an independent series of breast tumor samples (19 nonrelapsing and 14 relapsing), reduced expression of ESR1/ERα, IGFBP4, SNCG, BCL2, and FOS was observed in the relapsing group and was associated with a shorter overall survival. Low mRNA expression levels of ESR1/ERα, BCL2, and FOS were also associated with a shorter relapse-free survival (RFS). Using a Cox multivariate regression analysis, we identified BCL2 and FOS as independent prognostic markers associated with RFS. Finally, the BCL2/FOS signature was demonstrated to have more accurate prognostic value for RFS than ESR1/ERα alone (likelihood ratio test).

Conclusions

We identified molecular markers including a BCL2/FOS signature associated with tamoxifen failure; these markers may have clinical potential in the management of ER-positive breast cancer.  相似文献   
88.
Objectives  We examined the frequency of mammography screening among women who had had a screening mammogram recently and therefore generally did not need to repeat the examination.
Methods  A population-based sample of 50- to 69-year-old women were surveyed immediately before and 8 months after they received an invitation to participate in the first round of screening of the newly organized mammography screening programme in Geneva, Switzerland. These women also received a booklet that included the recommendation to have screening mammograms at 2-year intervals.
Results  The baseline survey identified 660 women who had had a mammogram within the previous 12 months. Of these, 23.2% [95% confidence interval (CI), 20.0–26.6] had an opportunistic mammogram and 4.1% (95% CI, 2.7–5.9) had an organized mammogram during follow-up. Women who had had their last mammogram 6–12 months prior to baseline (vs. more recently), intended to have a mammogram within the next 6 months, wished to receive more information on mammography screening, and had a history of surgical breast biopsy were more likely to have an unnecessary screening mammogram (either organized or opportunistic) during follow-up. Compared with women who had an opportunistic mammogram, women who had an organized mammogram were more likely to be of lower socioeconomic status, to have made their own screening decision and to have anticipated the date of their next mammogram by no more than a few months.
Conclusions  Opportunistic mammography screening in excess of recommendation is common, and persists despite explicit advice about recommended screening frequency.  相似文献   
89.
90.
The Kunjin strain of West Nile virus (WNVKUN) is a mosquito-transmitted flavivirus that can infect farmed saltwater crocodiles in Australia and cause skin lesions that devalue the hides of harvested animals. We implemented a surveillance system using honey-baited nucleic acid preservation cards to monitor WNVKUN and another endemic flavivirus pathogen, Murray Valley encephalitis virus (MVEV), on crocodile farms in northern Australia. The traps were set between February 2018 and July 2020 on three crocodile farms in Darwin (Northern Territory) and one in Cairns (North Queensland) at fortnightly intervals with reduced trapping during the winter months. WNVKUN RNA was detected on all three crocodile farms near Darwin, predominantly between March and May of each year. Two of the NT crocodile farms also yielded the detection of MVE viral RNA sporadically spread between April and November in 2018 and 2020. In contrast, no viral RNA was detected on crocodile farms in Cairns during the entire trapping period. The detection of WNVKUN and MVEV transmission by FTATM cards on farms in the Northern Territory generally correlated with the detection of their transmission to sentinel chicken flocks in nearby localities around Darwin as part of a separate public health surveillance program. While no isolates of WNVKUN or MVEV were obtained from mosquitoes collected on Darwin crocodile farms immediately following the FTATM card detections, we did isolate another flavivirus, Kokobera virus (KOKV), from Culex annulirostris mosquitoes. Our studies support the use of the FTATM card system as a sensitive and accurate method to monitor the transmission of WNVKUN and other arboviruses on crocodile farms to enable the timely implementation of mosquito control measures. Our detection of MVEV transmission and isolation of KOKV from mosquitoes also warrants further investigation of their potential role in causing diseases in crocodiles and highlights a “One Health” issue concerning arbovirus transmission to crocodile farm workers. In this context, the introduction of FTATM cards onto crocodile farms appears to provide an additional surveillance tool to detect arbovirus transmission in the Darwin region, allowing for a more timely intervention of vector control by relevant authorities.  相似文献   
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