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BackgroundMicrobial contamination of human skin allografts is a frequent cause of allograft discard. Our purpose was to evaluate the discard rate of skin bank contaminated allografts and specific procedures used to reduce allograft contamination without affecting safety.MethodsWe conducted at the Lille Tissue Bank a retrospective study of all deceased donors (n = 104) harvested from January 2018 to December 2018. Skin procurement was split into 3 zones: the back of the body and the two legs that were processed separately. It represented 433 cryopreserved skin allograft pouches of approximatively 500 cm² each. Donors were almost equally split between brain-dead (53%, 55/104) and cadaveric (47%, 49/104) donors.ResultsOut of all donors, 42 (40.5%) had at least one sampling zone with a positive microbiological test resulting in 106 (24%) contaminated skin pouches. The contamination rate did not vary according to the harvested zone or type of donor. Traumatic deaths showed significantly less contamination rates than other death types (p < 0.05). Contamination rate decreased with time spent in the antibiotic solution. The risk of having contaminated allografts was five-fold higher when the skin spent less than 96 h in the antibiotic cocktail (p < 0.05). According to our validation protocol, most donors (32/42, 76%) had skin allografts contaminated with bacteria (mainly Staphylococcus spp) compatible with clinical use. No recipient infection was recorded as a result of skin graft contaminated with saprophytic or non-pathogenic germs. By harvesting 3 separate zones per donor, the total surface area for clinical use increased by 53% for contaminated donors. Overall, the proportion of contamination-related discarded allografts was 3.2% (14/433 of pouches).ConclusionFew simple pragmatic measures (including skin incubation in the antibiotic bath for at least 96 h at 4 °C, splitting the skin harvesting areas to minimize the risk of cross-infection and clinical use of allografts contaminated with saprophytic and non-pathogenic germs) can reduce the discard rate of contaminated allografts without affecting clinical safety.  相似文献   
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Summary The need for further information on drug utilization patterns during pregnancy in different countries was assessed by reviewing literature obtained by hand and computer searches for the years 1960–1988.The 13 identified studies showed that pregnant women used an average of 4.7 drugs. The most commonly ingested medications were vitamins and iron preparations (almost all women), analgesics, antiemetics and antacids.However, the important variables taken into account differently in each study, such as date of surveillance, country, size of population, personal habits, and physiopathological and demographic characteristics, may it impossible to construct a comprehensive, detailed, up-to-date picture of drug utilization during pregnancy.The evaluation confirmed the need for systematic permanent surveillance of drug utilization in pregnancy, so as to avoid the use of data based on widely differing contexts, times and methods, in a field where knowledge is often derived from scanty information.This study was supported in part by the National Research Council (CNR, Rome, Italy), Convenzione Farmacologia Clinica  相似文献   
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Objectives To evaluate uterine artery resistance during multiovulation induction in relation to the implantation rate in patients attendingin vitro fertilization (IVF) cycles.Patients Multiovulation induction for IVF was monitored by daily determination of the pulsatility index (PI) of the uterine arteries, obtained by a transvaginal probe (6.5 MHz) implemented with color-flow imaging. Doppler data were obtained from 5 days before hCG administration to the day of follicular aspiration. One IVF cycle was monitored in 70 patients. In 17 patients, 41 IVF cycles were monitored until a successful attempt occurred.Results In the 70 patients studied during one IVF attempt, the PI of the uterine arteries significantly varied (P < 0.001) in the different phases of the cycle. In the 24 patients who conceived, a significantly lower PI (P < 0.03) was found throughout the cycle. This result was mainly due to a highly significant difference of PI values observed the day after hCG administration (P < 0.005). In the 17 patients who conceived after 1 to 4 negativein vitro fertilizations, no significant difference in PI was observed in the uterine artery resistance in cycles in which implantation was or was not successful.Conclusions Uterine artery resistance varies significantly during phases of the induction therapy. Uterine artery resistance is lower throughout the course of multiovulation induction in patients with higher pregnancy rates. The PI on the day after hCG administration was the best index of pregnancy rate. Low uterine artery resistance was present even in negative attempts in patients who eventually achieved a successful implantation. PI values 3 can be considered a favorable prognostic factor for future IVF cycles.Presented at the 49th Annual Meeting of the American Fertility Society, Montreal, 1993 and the 50th Annual Meeting of the American Fertility Society, November 5–10, 1994, San Antonio, Texas.  相似文献   
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Neurotrophins (NT), such as nerve growth factor (NGF), stimulate the growth and differentiation of several neuronal subpopulations in a distinct yet overlapping manner. Brain-metastatic human melanoma cells overexpress p75(NTR), the low-affinity neurotrophin receptor, and treatment of brain-metastatic cells with NGF stimulates extracellular matrix invasion and production of degradative enzymes in relation to the cellular expression of p75(NTR) Although human melanoma cells express high affinity neurotrophin receptors, such as TrkC (the putative receptor for NT-3), they do not express TrkA, the high-affinity NGF receptor. Using digoxigenin-labeled sense/antisense riboprobes against human p75(NTR) and NGF for in situ hybridization, we determined whether the expression of p75(NTR) and NGF mRNAs are related to brain metastasis of human melanoma. We detected p75(NTR) mRNA at the invasion front of human melanoma brain metastases, whereas p75(NTR) expression was not found in adjacent tissues. In contrast, human NGF mRNA levels were increased in tissues surrounding the melanoma lesions, supporting the notion that NGF and NT are important in determining melanoma brain-metastatic microenvironment. Using antibodies specific to p75(NTR), TrkC, NGF and related NT we found high but heterogeneous levels of p75(NTR) and TrkC expression in malignant melanomas metastatic to the brain. Lower levels of expression were found in primary melanomas or in metastatic melanomas to sites other than brain. Additionally, we found elevated levels of synthesis of NGF and NT-3 but not brain-derived neurotrophic factor (BDNF) or NT-4/5 in the brain tissues surrounding melanoma lesions. These studies support a role for NT and their receptors in the progression of melanomas to the brain-metastatic phenotype.  相似文献   
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Summary The relationship between different chemical modifications on morpholinylanthracyclines and their ability to overcome multidrug resistance (MDR) has been evaluated testing all compounds in vitro on LoVo and LoVo/DX human colon adenocarcinoma cells and in vivo on disseminated P388 and P388/DX murine leukemias.Results obtained led us to the following conclusions: 1) the insertion of the morpholinyl or the methoxymorpholinyl group on position 3 of the sugar moiety confers the ability to overcome MDR in vitro and in vivo; conversely, 4 morpholinyl compounds are effective on MDR cells only in vitro and result inactive in vivo on DX-resistant leukemia; 2) all chemical modifications performed on 3 morpholinyl or methoxymorpholinyl derivatives, that is substitutions on the aglycone or on position 2 of the morpholino ring, do not interfere with the activity of the compounds: all derivatives present in fact the same efficacy on sensitive and resistant models.It is concluded that position 3 in the sugar moiety plays a crucial role in the ability of morpholinylanthracyclines to overcome MDR.  相似文献   
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