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Prostate cancer is a serious threat to men's health, so it is necessary to develop the techniques for early detection of this malignancy. Radiolabeled peptides are the useful tools for diagnosis of prostate cancer. In this research, we designed a new HYNIC‐conjugated GnRH analogue and labeled it by 99mTc with tricine/EDDA as coligands. We used aminohexanoic acid (Ahx) as a hydrocarbon linker to generate 99mTc‐(tricine/EDDA)‐HYNIC‐Ahx‐[DLys6]GnRH. The radiopeptide exhibited high radiochemical purity and stability in solution and serum. Two human prostate cancer cell lines LN‐CaP and DU‐145 were used for cellular experiments. The binding specificity and affinity of radiopeptide for LN‐CaP were superior to DU‐145 cells. The Kd values for LN‐CaP and DU‐145 cells were 41.91 ± 7.03 nM and 55.96 ± 10.56 nM, respectively. High kidney uptake proved that the main excretion route of radiopeptide was through the urinary system. The tumor/muscle ratio of 99mTc‐HYNIC‐Ahx‐[DLys6]GnRH was 4.14 at 1 hr p.i. that decreased to 2.41 at 4 hr p.i. in LN‐CaP tumor‐xenografted nude mice. The blocking experiment revealed that the tumor uptake was receptor‐mediated. The lesion was visualized clearly using 99mTc‐[DLys6]GnRH at 1 hr p.i. Accordingly, this research highlights the capability of 99mTc‐(tricine/EDDA)‐HYNIC‐Ahx‐[DLys6]GnRH peptide as a promising agent for GnRHR‐expressing tumor imaging.  相似文献   
3.

Aim

Extended liver resection has increased during the last decades. However, hepatic hemodynamic changes after resection and the consequent complications like post hepatectomy liver failure are still a challenging issue. The aim of this study was to systematically evaluate the role of stepwise liver resection on hepatic hemodynamic changes.

Methods

To evaluate this effect we performed 25, 50, and 75 % sequential liver resections in 10 pigs. Before and after each resection, the hepatic artery flow and portal vein flow in relation to the remnant liver volume (RLV) as well as hepatic vascular pressures were measured and compared between the groups.

Results

Following sequential liver resection, the hepatic artery flow /100 g decreases and the portal vein flow increases up to 17 and 167 % following extended liver resection (75 %), respectively. Also, during stepwise liver resection, the portal vein pressure increases gradually up to 33 % following extended hepatectomy (75 %).

Conclusion

Sequential decrease in the RLV decreases the hepatic artery flow /100 g and increases the portal vein flow /100 g and portal vein pressure. As the consequence, the liver goes under more poor-oxygenated blood supply and higher pressure. This may be one of the most important mechanisms of the post hepatectomy liver failure in case of extended liver resection.
  相似文献   
4.
As cytokines, including interleukin-4 (IL-4), seem to have a pivotal role in the pathogenesis of juvenile idiopathic arthritis (JIA), this study is aimed at investigating of association of polymorphisms in IL-4 and IL-4 receptor α (IL-4RA) genes with susceptibility to JIA. A case-control study was conducted on 53 patients with JIA and 139 healthy unrelated controls. Single nucleotide polymorphisms of IL-4 gene at positions -1098, -590, and -33, as well as IL-4RA gene at position +1902 were genotyped using polymerase chain reaction with sequence-specific primers method and compared between patients and healthy individuals. At the allelic level, C allele at IL-4 -33 was found to be more frequent in patients compared to control (P value <0.01). At the genotypic level, CC genotype at IL-4 -590 (P value <0.01), together with CC and TT genotypes at IL-4 -33 (P value <0.01), were significantly higher in patients with JIA, while TC genotypes at IL-4 -590 and -33 positions were found to be lower in case group (P value <0.01). At the haplotypic level, IL-4 (positions -1098, -509, -33) TTC, GCC, and TTT haplotypes were significantly lower than controls (P value <0.01, P value?=?0.03, and P value?=?0.04, respectively). Although, TCC haplotype at the same positions was found to be higher in patients (P value <0.01). Polymorphic site of +1902 IL-4RA gene did not differ between cases and controls. Polymorphisms in promoter region of IL-4 but not IL-4RA genes confer susceptibility to JIA and may predispose individuals to adaptive immune responses.  相似文献   
5.

Background

Lead aVR provides prognostic information in various settings in patients with ischemia. We aim to investigate the role of a positive T wave in lead aVR in non‐ST segment myocardial infarction (NSTEMI).

Methods

In a prospective cohort study, we included 400 patients with NSTEMI. Presentation electrocardiogram (ECG) was investigated for presence of a positive T wave as well as ST segment elevation (STE) in aVR and study variables were compared. Predictors of primary outcome defined as hospital major adverse cardiovascular events (MACE) and secondary outcome, defined as three‐vessel coronary disease and/or left main coronary artery stenosis (3VD/LMCA) stenosis in angiography, were determined in multivariate logistic regression analysis.

Results

Patients with a positive T wave in aVR were significantly older and were more likely to be female. Left ventricular ejection fraction was significantly lower in patients of positive T group. Positive T group was more likely to have 3VD/LMCA stenosis (58.3% vs. 19.8%, p < .001). The prevalence of a positive T wave in aVR was significantly higher in MACE group (54.9 % vs. 24.8%, p < .001). However, in multivariate analysis, it was not an independent predictor of MACE (OR: 1.083 95% CI: [0.496–2.365], p: .841). Though, it was independently associated with presence of 3VD/LMCA stenosis (OR: 3.747 95% CI: [2.058–6.822], p < .001).

Conclusion

Though positive T wave in lead aVR was more common in patients with MACE; it was not an independent predictor. Additionally, a positive T wave in aVR was an independent predictor of 3VD/LMCA stenosis in NSTEMI.
  相似文献   
6.
Journal of Molecular Neuroscience - Recent studies have shown contribution of long non-coding RNAs (lncRNAs) in the pathogenesis of a number of psychiatric disorders. In the current study, we...  相似文献   
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In 2005, a major Level I trauma center closed in Los Angeles County, leading to media speculation that the sudden expansion of our catchment area would adversely affect outcome. We sought to determine whether the closure led to longer transport times and increased trauma morbidity and mortality at our Level I trauma center. Annual patient volume, paramedic transport times, injury severity score (ISS), mechanism of injury, complication rate, and mortality were retrospectively compared between two time periods, Period 1 (1997-2005, before closure) and Period 2 (March 1, 2005 to March 1, 2006, after closure), using multivariable logistic regression models. Median monthly patient volume rose from 123 patients to 190 patients in Period 2 (P < 0.01). Median transport time increased from 12 to 13 minutes (P = 0.004) and median ISS increased from four to five (P < 0.01) in Period 2. The proportion of patients with ISS > 15 increased from 17 to 24 per cent as well (P < 0.01). After accounting injury severity, the adjusted mortality rate decreased in Period 2 (odds ratio 0.69, P = 0.03) and the adjusted complication rate was unchanged (odds ratio 1.16, P = 0.2). In conclusion, the closure of a Level I trauma center resulted in a significant increase in trauma patient volume and injury severity, as well as a slight increase in paramedic transport times. However, the adjusted complication rate was unchanged, and the adjusted mortality rate actually improved.  相似文献   
9.
Glial cell line derived neurotrophic factor (GDNF) is a potent survival factor for several types of neurons. GDNF binds with high affinity to GDNF-family receptor α-1 (GFRα-1). This receptor is expressed in different areas of the brain, including the hippocampus and dentate gyrus. By using in situ hybridization and immunohistochemistry, we found that 19% to 37% of glutamic acid decarboxylase (GAD) expressing neurons co-expressed GFRα-1 in the hippocampus. GFRα-1/GAD co-expression was found mainly in the stratum (s) pyramidale (29–37%) and s. oriens (20–25%). Further characterization of GFRα-1 expressing interneurons, based on their calcium-binding protein immunoreactivity, demonstrated that many parvalbumin (PV) immunoreactive neurons express GFRα-1 in the s. pyramidale of CA1 (72%), CA2 (70%) and CA3 (70%) subfields of the hippocampus. GFRα-1/PV double labeled neurons were also detected in the s. oriens of CA1 (52%), CA2 (27%) and CA3 (36%) subfields. The expression of GFRα-1 in principal neurons and in a specific sub-population of GABAergic neurons (PV-containing neurons) suggest that GDNF might modulate, in a selective manner, functions of the entire adult hippocampus.  相似文献   
10.
Background: PTPN22 plays a crucial role in regulating the function of various cells of the immune system, particularly T cells. Polymorphisms of the PTPN22 gene have been associated with many autoimmune diseases, including type 1 diabetes (T1D) which is a T-cell-mediated disease.

Objective: The present study was aimed at genotyping of an Iranian population for five polymorphisms of the PTPN22 gene.

Methods: The study population consisted of 99 T1D patients and 100 healthy controls. We genotyped five single-nucleotide polymorphisms (SNPs) (rs12760457, rs1310182, rs1217414, rs33996649, and rs2476601) of the PTPN22 gene.

Results: Regarding the variant rs2476601, genotypes AG and GG were increased and decreased in T1D patients compared with controls, respectively. Further, alleles G and A of this SNP were found to be decreased and increased in T1D patients, respectively (p value = 0.001). However, T1D and control groups did not differ on genotype distribution or allele frequency for other investigated SNPs.

Conclusions: The PTPN22 rs2476601 minor allele (A) was associated with T1D in Iran, accounting for its pathophysiology in autoimmune diseases.  相似文献   

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