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821.
822.
BackgroundNon-small cell lung cancer (NSCLC) is leading cause of cancer related death and the survival rate for patients with NSCLC remain poor so early diagnosis of NSCLC represents the best opportunity for cure. Cell-free DNA (cf-DNA) is extracellular nucleic acids found in cell-free plasma/serum of humans, given the recent approval of a liquid biopsy in lung cancer, the use of circulating tumor DNA as a novel non-invasive diagnostic and prognostic biomarker is promising.ObjectivesStudying whether the concentrations of circulating Cell Free DNA in serum can be used as a diagnostic and prognostic biomarker for NSCLC patients.MethodThis study was carried out on 140 subjects included 60 patients with non small cell lung cancer,40 patients with Chronic Obstructive Pulmonary Disease (COPD) and 40 healthy controls. Quantitative analysis of serum circulating cf-DNA was done b y AlU-based quantitative real time PCR. Serum level of CEA was measured by ELISA.ResultsNSCLC patients demonstrated significantly higher values of each of ALU 215, ALU 247, and DNA integrity than both COPD patients and controls. On ROC curve analysis, the total accuracy of ALU 247, ALU 115, DNA integrity (92.1%, 83.6%, 56.4%) at cutoff points (325, 565 & 0.48) respectively. On combining both DNA integrity and CEA, improved sensitivity to 93.3% was noted. For NSCLC patients, ALU 115 & ALU 247 increased significantly with more advanced stage and highest level was noticed in metastatic patients. Regarding survival there was better overall survival among patients with low DNA integrity.ConclusionSerum cf-DNA concentrations and integrity index may be valuable tool in early diagnosis of NSCLC and prediction of prognosis of those patients.  相似文献   
823.
The magnetic particles have a significant influence on the immunoassay detection and cancer therapy. Herein, the chemiluminescence immunoassay combined with the magnetic particles (MPCLIA) was presented for the clinical determination and analysis of human epididymis protein 4 (HE4) in the human serum. Under the optimized experiment conditions, the secure MPCLIA method can detect HE4 in the broader range of 0–1000 pmol/L, with a lower detection limit of 1.35 pmol/L. The satisfactory recovery rate of the method in the serum ranged from 83.62% to 105.10%, which was well within the requirement of clinical analysis. Moreover, the results showed the good correlation with enzyme-linked immunosorbent assay (ELISA), with the correlation coefficient of 0.9589. This proposed method has been successfully applied to the clinical determination of HE4 in the human serum.  相似文献   
824.

Background

Intravascular papillary endothelial hyperplasia (known also as Masson’s tumor) is a benign vascular lesion that commonly occurs in the skin and is rarely found in solid organs, especially in the kidney. In what follows, we will look into the first case of an unexpectedly diagnosed Masson’s tumor of the kidney presenting as a suspicious renal cyst.

Case presentation

A 61-year-old Arab man presented with a left renal cyst, incidentally revealed by ultrasonography. The laboratory values were unremarkable. Computed tomography and magnetic resonance imaging demonstrated a 38 mm left renal midportion Bosniak IV cyst. Our patient underwent a radical nephrectomy. Histopathology revealed the diagnosis of intravascular papillary endothelial hyperplasia. There was no recurrence detected after 9 years of follow-up.

Conclusions

Renal intravascular papillary endothelial hyperplasia is a rare benign tumor which can mimic a suspicious renal mass on radiological findings. Thus, this entity should be considered more often in the thick of the diagnostic possibilities in order to avoid unnecessary nephrectomies.
  相似文献   
825.
SECTR is a novel multimodal imaging platform for combined volumetric optical coherence tomography (OCT) and en face spectrally encoded reflectometry (SER). The authors demonstrate three‐dimensional motion‐tracking with millisecond temporal and micron spatial resolution using complementary data from OCT and SER, and preliminary algorithms and results showing real‐time image aiming and multi‐volumetric mosaicking for reconstruction of wide‐field composites. The image shows a noninvasively imaged nine‐field mosaic of in vivo human retina and depth‐resolved visualization of tissue microstructures. Further details can be found in the article by Mohamed T. El‐Haddad, Ivan Bozic, and Yuankai K. Tao ( e201700268 )

  相似文献   

826.
827.
Toxigenic Aspergillus species produce mycotoxins that are carcinogenic, hepatotoxic and teratogenic immunosuppressing agents in both human and animals. Kenya frequently experiences outbreaks of aflatoxicosis with the worst occurring in 2010, which resulted in 215 deaths. We examined the possible reasons for these frequent aflatoxicosis outbreaks in Kenya by studying Aspergillus flavus diversity, phenotypes and mycotoxin profiles across various agricultural regions. Using diagonal transect random sampling, maize kernels were collected from Makueni, Homa Bay, Nandi, and Kisumu counties. Out of 37 isolates, nitrate non-utilizing auxotrophs complementation test revealed 20 vegetative compatibility groups. We designated these groups by the prefix “KVCG”, where “K” represented Kenya and consequently assigned numbers 1–20 based on our findings. KVCG14 and KVCG15 had highest distribution frequency (n = 13; 10.8 %). The distribution of the L-, S- and S-/L-morphotypes across the regions were 57 % (n = 21); 7 % (n = 3) and 36 % (n = 13), respectively. Furthermore, a unique isolate (KSM015) was identified that had characteristics of S-morphotype, but produced both aflatoxins B and G. Coconut agar medium (CAM) assay, TLC and HPLC analyses confirmed the presence or absence of aflatoxins in selected toxigenic and atoxigenic isolates. Diversity index (H′) analyses ranged from 0.11 (Nandi samples) to 0.32 (Kisumu samples). Heterokaryon compatibility ranged from 33 % (for the Makueni samples, n = 3) to 67 % (Nandi samples, n = 6). To our knowledge, this is the first reported findings for A. flavus diversity and distribution in Nandi, Homa Bay and Kisumu counties and may assist current and future researchers in the selection of biocontrol strategies to mitigate aflatoxin contamination as has been researched in Makueni and neighbouring counties.  相似文献   
828.
829.
Alternaria alternata is the most common fungal pathogen of tomatoes in Upper Egypt. Morphological identification of this fungus is challenging; therefore, this study searched for new classification tools based on molecular techniques. Using a dilution plating method, 67 strains of A. alternata were isolated from 34 samples of rotten tomato fruits representing the Giza 80 and Edkawy cultivars. The collected strains were identified using the amplification products of the internal transcribed spacer (ITS) region, glyceraldehyde 3‐phosphate dehydrogenase (Gpd) and Alt a1, which is a gene involved in the production of most of the allergens produced by A. alternata. The screening revealed that A. alternata constituted more than half of the total fungi recovered from rotten tomatoes in this study. According to the phylogenetic analysis using these three loci, the collected strains clustered in accordance with the host cultivar type from which they had been isolated. Specific gene random primer polymerase chain reaction (SGRP‐PCR) techniques indicated that the A. alternata population in the tested region has a high genetic diversity. The pathogenicity test showed that most of the A. alternata isolates (67.2%) were highly pathogenic, and no correlation was found between the phylogenetic analysis and pathogenicity. In addition, the influence of the fungicide Disan 80% on the collected strains showed significant differences that were attributed to the source of isolation.  相似文献   
830.
Lead (Pb) is a ubiquitous and toxic heavy metal and it can damage the immune system in humans and animals. Many researchers have reported that Selenium (Se) could possess various pharmacological effects in mammals. However, few studies have been carried out to investigate the protective role of Se in birds, especially in chickens. In this study, we investigated the protective effects of Se against Pb-induced inflammatory responses and the expression of heat shock proteins (HSPs) in peripheral blood neutrophils. One hundred eighty Hy-Line brown chickens were randomly divided into the control group (Con group), Se supplementation group (+Se group), Pb supplementation group (+Pb group), and the Se and Pb compound group (Se+Pb group). On the 90th day of the experiment, the peripheral blood was collected to extract neutrophils, and then, the levels of HSPs and cytokines were examined. The results showed that, after Pb treatment, the levels of IL-(1β, 1R, 4, 8, 10, and 12β), TGF-β4, and HSP (27, 40, 60, 70, and 90) mRNA were significantly increased and levels of IL-2 and IFN-γ mRNA were decreased compared with those in the control group. Compared with the control group, the protein levels of HSP60 and HSP70 were also increased in the Pb treatment group. Co-administration of Se (1 mg/kg/day) and Pb resulted in a reversal of the Pb-induced cytokine changes in neutrophils accompanied by a significant decrease in HSPs. Our study demonstrated that Pb could decrease the immune function via changing the expression of cytokines and HSPs in chicken neutrophils, but Se could relieve the toxic effect induced by Pb.  相似文献   
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