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Objective: Animal environments for the growth of stem cells cause the transmission of some diseases and immune problems for the recipient. Accordingly, replacing these environments with healthy environments, at least with human resources, is essential.  One of the media that can be used as an alternative to animal serums is Wharton acellular jelly (AWJ).  Therefore, in this study, we intend to replace FBS with Wharton jelly and investigate its effect on the expression of megakaryocyte-related genes and markers in stem cells. Materials and Methods: In this study, cord blood-derived CD34 positive HSCs were cultured and expanded in the presence of cytokines including SCF, TPO, and FLT3-L. Then, the culture of expanded CD34 positive HSCs was performed in two groups: 1) IMDM culture medium containing 10% FBS and 100 ng / ml thrombopoietin cytokine 2) IMDM culture medium containing 10% AWJ, 100 ng / ml thrombopoietin cytokine.  Finally, CD41 expressing cells were analyzed with the flow cytometry method. The genes related to megakaryocyte lineage including FLI1 and GATA2 were also evaluated using the RT-PCR technique.  Results: The expression of CD41, a specific marker of megakaryocyte lineage in culture medium containing Wharton acellular jelly was increased compared to the FBS group. Additionally, the expression of GATA2 and FLI1 genes was significantly increased related to the control group. Conclusion: This study provided evidence of differentiation of CD34 positive hematopoietic stem cells from umbilical cord blood to megakaryocytes in a culture medium containing AWJ.  相似文献   
3.
Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina.  相似文献   
4.
ObjectivesOur aim was to evaluate the effect of the updated European Organization for Research and Treatment of Cancer (EORTC) and Mycoses Study Group 2019 definitions for invasive pulmonary aspergillosis (IPA) on patient classification and the related all-cause 12-week mortality.MethodsIn this retrospective cohort study from our tertiary care centre, we reclassified patients with haematological malignancy who underwent bronchoalveolar lavage between 2014 and 2019 for suspected IPA using the novel EORTC 2019 criteria. We performed receiver operating characteristic curve analysis to define the optimal cut-off for positive PCR and galactomannan and present survival analyses and their possible association with these diagnostic criteria through post hoc comparisons with log rank and Cox regression.ResultsFrom 323 episodes of suspected IPA in 282 patients, 73 were reclassified: 31 (42.5%) from possible to probable IPA, 5 (6.8%) from EORTC criteria not met to probable IPA, and 37 (50.7%) from EORTC criteria not met to possible IPA. Probable IPA increased therefore 11.1% (64/323, 19.8% to 100/323, 30.9%), mostly due to positive PCR (31/36, 86.1%). There was no difference in mortality between newly defined possible and probable IPA (log rank p = 0.950). Mortality was higher in probable cases with lower cycle thresholds (Ct values) versus higher Ct values (p = 0.004). Receiver operating characteristic curve analysis showed an optimal Ct value cut-off of 36.8 with a sensitivity of 75% (95% CI 64.9%–85.1%) and a specificity of 61.7% (95% CI 53.5–69.9) for 12-week mortality.DiscussionThe new EORTC criteria led to 11.1% more probable IPA diagnoses, mostly due to Aspergillus PCR. Restricting positive PCR to below a certain threshold might improve the discrimination of the new EORTC IPA categories for mortality.  相似文献   
5.
目的 探讨滋肾育胎丸加减方预防抗磷脂抗体(ACA)阳性者不良妊娠结局的效果及机制研究。方法 选取2016年2月至2019年2月我院收治的89例ACA阳性,先兆性流产或有习惯性流产(RSA)史患者,将采用西医治疗的40例作为对照组,将采用西医联合滋肾育胎丸加减方治疗的49例作为观察组,比较两组中医证候疗效、中医证候积分、ACA-IgA、ACA-IgM、ACA-IgG、凝血指标[血小板聚集功能(PAF)、活化蛋白C(PC)、抗凝血酶(AT)、纤溶酶原激活抑制物-1(PAI-1)]、Th1/Th2细胞因子[干扰素γ(IFN-γ)、白介素-2(IL-2)、白介素-4(IL-4)、白介素-10(IL-10)]、妊娠结局、安全性。结果 治疗2周后检测ACA,观察组2例未降低,对照组11例未降低,观察组未降低患者占比低于对照组(P<0.05);观察组总有效率100.00%高于对照组85.00%(P<0.05);观察组治疗4周、7周后中医证候积分低于对照组(P<0.05);观察组治疗4周、7周后ACA-IgA、ACA-IgM、ACA-IgG低于对照组(P<0.05);观察组治疗4周、7周后PAF、PAI-1低于对照组,PC、AT高于对照组(P<0.05);观察组治疗4周、7周后IFN-γ、IL-2低于对照组,IL-4、IL-10高于对照组(P<0.05);观察组活产率95.92%高于对照组80.00%(P<0.05);组间不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 动态监测ACA对滋肾育胎丸加减方精准应用具有指导意义,指导滋肾育胎丸加减方通过调理脏腑、气血、经络功能,改善先兆性流产或有RSA史患者临床症状及凝血因子指标,降低ACA水平,并可改善患者免疫耐受功能,提高胎儿活产率,且安全性高。  相似文献   
6.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
7.
Cyclotron-produced copper-64 radioisotope tracers offer the possibility to perform both diagnostic investigation by positron emission tomography (PET) and radiotherapy by a theranostic approach with bifunctional chelators. The versatile chemical properties of copper add to the importance of this isotope in medicinal investigation. [64Cu][Cu (ATSM)] has shown to be a viable candidate for imaging of tumor hypoxia; a critical tumor microenvironment characteristic that typically signifies tumor progression and resistance to chemo-radiotherapy. Various production and radiosynthesis methods of [64Cu][Cu (ATSM)] exist in labs, but usually involved non-standardized equipment with varying production qualities and may not be easily implemented in wider hospital settings. [64Cu][Cu (ATSM)] was synthesized on a modified GE TRACERlab FXN automated synthesis module. End-of-synthesis (EOS) molar activity of [64Cu][Cu (ATSM)] was 2.2–5.5 Ci/μmol (HPLC), 2.2–2.6 Ci/μmol (ATSM-titration), and 3.0–4.4 Ci/μmol (ICP-MS). Radiochemical purity was determined to be >99% based on radio-HPLC. The final product maintained radiochemical purity after 20 h. We demonstrated a simple and feasible process development and quality control protocols for automated cyclotron production and synthesis of [64Cu][Cu (ATSM)] based on commercially distributed standardized synthesis modules suitable for PET imaging and theranostic studies.  相似文献   
8.
ABSTRACT

Objective: Dry eye is reported to be associated with several neurological diseases. The aim of this study is to evaluate the patients with hemiplegia after stroke for dry eye and compare their results with a control group.

Materials and methods: Forty-five patients with hemiplegia and 45 individuals as the control group were included in the study. Tear function tests (Schirmer and tear breakup time) and a dry eye questionnaire for dry eye symptoms (ocular surface disease index) were performed and the results of the two groups were compared.

Results: Schirmer test results were significantly lower in the post-stroke hemiplegia group compared to the control group (11.3 ± 8.2 mm and 20.6 ± 11.6 mm, respectively, p < .001). Tear breakup time results were significantly lower in the post-stroke hemiplegia group compared to the control group (7.9 ± 3.1 s and 12.1 ± 4.3 s, respectively, p < .001). Ocular surface disease index scores were not significantly different between hemiplegia and control groups (21.6 ± 20.0 and 19.8 ± 13.9, respectively, p = .635). Schirmer scores lower than 10 mm (60% and 30%, p < .001) and tear breakup time results lower than 10 s (65.6% and 28.9%, p < .001) were also higher in the hemiplegia group compared to control group.

Conclusion: We found lower Schirmer test and tear breakup time results and similar OSDI scores in hemiplegia patients compared to controls. Hemiplegia patients may have dry eye without typical symptoms. This should be taken into consideration in the follow-up and rehabilitation of post-stroke hemiplegia patients.  相似文献   
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Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia.  相似文献   
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