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991.
Retinoblastoma (RB) is a childhood cancer developing in the retina due to RB1 pathologic variant. Herein we are evaluating the oncogenic mutations in the RB1 gene and the inheritance patterns of RB in the Jordanian patients. In this prospective study, the peripheral blood of 50 retinoblastoma patients was collected, genomic DNA was extracted, mutations were identified using Quantitative multiplex PCR (QM-PCR), Allele-specific PCR, Next Generation Sequencing analysis, and Sanger sequencing. In this cohort of 50 patients, 20(40%) patients had unilateral RB and 30(60%) were males. Overall, 36(72%) patients had germline disease, 17(47%) of whom had the same RB1 pathologic variant detected in one of the parents (inherited disease). In the bilateral group, all (100%) patients had germline disease; 13(43%) of them had inherited mutation. In the unilateral group, 6(30%) had germline disease, 4(20%) of them had inherited mutation. Nonsense mutation generating a stop codon and producing a truncated non-functional protein was the most frequent detected type of mutations (n = 15/36, 42%). Only one (2%) of the patients had mosaic mutation, and of the 17 inherited cases, 16(94%) had an unaffected carrier parent. In conclusion, in addition to all bilateral RB patients in our cohort, 30% of unilateral cases showed germline mutation. Almost half (47%) of germline cases had inherited disease from affected (6%) parent or unaffected carrier (94%). Therefore molecular screening is critical for the genetic counseling regarding the risk for inherited RB in both unilateral and bilateral cases including those with no family history.  相似文献   
992.
Through the condensation of isatin (indoline-2, 3-dione) and aniline in a 1:1 ratio, a Schiff base ligand was synthesized and characterized via (1H-NMR, mass, IR, UV-Vis) spectra. Elemental analyses, spectroscopy (1H-NMR, mass, UV-Vis), magnetic susceptibility, molar conductivity, mass spectra, scanning electron microscope (SEM), and thermal analysis have all been used to characterize a series of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) metal complexes derived from the titled ligand. The metal-to-ligand ratio is 1:1, according to the analytical data. The Schiff base ligand displayed bidentate behavior with NO coordination sites when it bonded to metal ions, as seen by the IR spectra. The magnetic moment measurement and UV-Vis spectral investigation showed the octahedral geometry of the Cr(III), Fe(III), Co(II), Ni(II), and Zn(II) complexes, whereas they suggested the tetrahedral geometry of the Mn(II), Cu(II), and Cd(II) complexes. The thermal analysis study confirmed the presence of both hydrated and coordinated water molecules in all the compounds, except for the Mn(II) complex, and showed that the complexes decomposed in three or five decomposition steps leaving the corresponding metal oxide as a residue. The ligand and its metal complexes’ antibacterial efficacy were evaluated. The findings showed that the metal complexes had stronger antibacterial properties than the ligand alone. The ligand and its metal complexes’ anticancer properties were also investigated. A DFT investigation is also reported to gather information regarding the electronic features of the ligand and its metal complexes. Finally, drug-likeness and ADME characteristics were also calculated as parameters.  相似文献   
993.

Background:

The human kallikrein-related peptidase family consists of 15 genes. Twelve of these genes are overexpressed in ovarian cancer and may represent potential markers for diagnosis, prognosis, and/or response to treatment. The aim of this study was to determine the prognostic significance of kallikrein-related peptidase 6 (KLK6) and kallikrein-related peptidase 13 (KLK13) in epithelial ovarian cancer by quantifying gene expression levels with tumour pathology and patient survival data.

Methods:

Total RNA was isolated from 106 patients diagnosed with primary ovarian cancer, as well as 8 normal ovary controls. Samples were analysed by quantitative real-time PCR for KLK6 and KLK13 expression. Correlation between kallikrein gene expression and clinical characteristics was evaluated with the χ2-test. Survival analysis was performed using Kaplan–Meier and Cox proportional hazards regression models.

Results:

Expression levels of both KLK6 and KLK13 mRNA were significantly increased in invasive cancers relative to normal ovaries (P=0.002 and 0.039 respectively). High KLK6 and KLK13 expression was an indicator of poor prognosis, with patients having a shorter recurrence-free survival (P=0.002 and 0.027 respectively). High KLK6 expression was also significantly associated with lower overall survival (P=0.011). When subjected to multivariate analysis, patients with either high KLK6 or KLK13 were 3- and 2.2-fold, respectively, more likely to have a recurrence than patients with low kallikrein expression.

Conclusion:

These data show increased mRNA expression of KLK6 and KLK13 in ovarian cancer compared to normal ovarian tissues. High KLK6 or KLK13 expression in primary ovarian tumours can significantly predict prognosis in terms of recurrence-free survival and overall survival. In all, this study shows KLK6 and KLK13 as potential biomarkers and may be therapeutic targets for treatment of ovarian cancer.  相似文献   
994.
Qureshi AI  Ziai WC  Yahia AM  Mohammad Y  Sen S  Agarwal P  Zaidat OO  Suarez JI  Wityk RJ 《Neurosurgery》2003,52(5):1033-9; discussion 1039-40
OBJECTIVE: We sought to determine the long-term stroke-free survival of patients who present with ischemic events related to intracranial vertebrobasilar stenosis. METHODS: A retrospective cohort of patients diagnosed with symptomatic vertebrobasilar stenosis on the basis of magnetic resonance angiography and/or conventional angiography was identified at four academic medical centers. Patients' clinical and follow-up information was obtained through hospitalization records, clinic visits, and telephone interviews. Kaplan-Meier analysis was performed to determine the rate of stroke-free survival for a 5-year period. Cox proportional hazards analysis was performed to determine the effect of demographic and clinical factors on stroke-free survival. RESULTS: A total of 102 patients were included, whose mean age was 64 +/- 12 years. Fifty-five (54%) of the patients were men. The mean follow-up period was 15 +/- 15.9 months (range, 1-60 mo). During the follow-up period, 14 (14%) of the patients experienced recurrent stroke. The overall mortality rate was 21% (n = 21). Stroke-free survival, calculated by using the Kaplan-Meier curve, was 76% at 12 months (95% confidence interval [CI], 66-83%) and 48% at 5 years (95% CI, 27-65%). The risk of recurrent stroke was 10.9 per 100 patient-years, and the rate of recurrent stroke and/or death was 24.2 per 100 patient-years. Cox proportional hazards analysis revealed that increasing age (hazards ratio, 1.05; 95% CI, 1.00-1.09) decreased stroke-free survival. Treatment with either antiplatelet agents or warfarin (hazards ratio, 0.018; 95% CI, 0.003-0.11) had a protective effect on stroke-free survival after adjusting for age, sex, race, hypertension, diabetes mellitus, smoking, hyperlipidemia, and lesion location. CONCLUSION: A low rate of stroke-free survival is observed in patients with symptomatic vertebrobasilar stenosis. Further studies are required to evaluate new medical and endovascular treatment options for this group of patients to improve long-term stroke-free survival.  相似文献   
995.
Accurate identification of early onset neonatal sepsis (EOS) is challenging. Blood culture has been considered as a gold standard method but the identification of EOS is intricate by a high false-negative results. This review provides an overview of biomarkers as indicators for the diagnosis of EOS. There is an affluence of studies appraising diagnostic indicators in the identification of EOS. Acute-phase reactants, cytokines, and cell surface antigens have been investigated as indicators for EOS, but none of them are presently in routine clinical setting. Despite the promising data for some immunologic biomarkers, present evidence shows that none of them can constantly diagnose 100% of infections. IL-6 is the most potent marker for evaluation of EOS prognosis. Procalciton (PCT) and C-reactive protein (CRP) are appropriate indicators for the detection and monitoring of antibiotics therapy. A panel of sepsis biomarkers along with presently routine tests will make easy earlier identification, appropriate management, and improved outcome may be more efficient than single indicator.  相似文献   
996.
The purpose of this study was to identify the optimal tracer kinetic model from T1‐weighted dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) data and evaluate whether parameters estimated from the optimal model predict tumor aggressiveness determined from histopathology in patients with papillary thyroid carcinoma (PTC) prior to surgery. In this prospective study, 18 PTC patients underwent pretreatment DCE‐MRI on a 3 T MR scanner prior to thyroidectomy. This study was approved by the institutional review board and informed consent was obtained from all patients. The two‐compartment exchange model, compartmental tissue uptake model, extended Tofts model (ETM) and standard Tofts model were compared on a voxel‐wise basis to determine the optimal model using the corrected Akaike information criterion (AICc) for PTC. The optimal model is the one with the lowest AICc. Statistical analysis included paired and unpaired t‐tests and a one‐way analysis of variance. Bonferroni correction was applied for multiple comparisons. Receiver operating characteristic (ROC) curves were generated from the optimal model parameters to differentiate PTC with and without aggressive features, and AUCs were compared. ETM performed best with the lowest AICc and the highest Akaike weight (0.44) among the four models. ETM was preferred in 44% of all 3419 voxels. The ETM estimates of Ktrans in PTCs with the aggressive feature extrathyroidal extension (ETE) were significantly higher than those without ETE (0.78 ± 0.29 vs. 0.34 ± 0.18 min?1, P = 0.005). From ROC analysis, cut‐off values of Ktrans, ve and vp, which discriminated between PTCs with and without ETE, were determined at 0.45 min?1, 0.28 and 0.014 respectively. The sensitivities and specificities were 86 and 82% (Ktrans), 71 and 82% (ve), and 86 and 55% (vp), respectively. Their respective AUCs were 0.90, 0.71 and 0.71. We conclude that ETM Ktrans has shown potential to classify tumors with and without aggressive ETE in patients with PTC.  相似文献   
997.
The World Health Organization defines the multisystem inflammatory syndrome in children (MIS-C) as a new syndrome reported in patients aged < 19 years old who have a history of exposure to SARS-CoV-2. The onset of this syndrome is characterized by persistent fever that is associated with lethargy, abdominal pain, vomiting and/or diarrhea, and, less frequently, rash and conjunctivitis. The course and severity of the signs and symptoms vary; in some children, MIS-C worsens rapidly and can lead to hypotension, cariogenic shock, or even damage to multiple organs. The characteristic laboratory findings are elevated markers of inflammation and heart dysfunction. The most common radiological findings are cardiomegaly, pleural effusion, signs of heart failure, ascites, and inflammatory changes in the right iliac fossa. In the context of the current COVID-19 pandemic, radiologists need to know the clinical, laboratory, and radiological characteristics of this syndrome to ensure the correct diagnosis.  相似文献   
998.
BackgroundThe Neonatal Tetanus Surveillance System (NTSS) in Yemen was established in 2009 to identify high-risk areas, determine trends, and evaluate elimination activities. Since its launch, the NTSS had never been evaluated.ObjectiveThis study aimed to assess the performance of NTSS and determine its strengths and weaknesses to recommend improvements.MethodsThe US Centers for Disease Control and Prevention (CDC) guidelines were used for evaluating the NTSS. Stakeholders at the central, district, and facility levels were interviewed to rate the attributes of the NTSS. The percentage scores for attributes were ranked as poor (<60%), average (≥60% to <80%) and good (≥80%).ResultsThe overall usefulness score percentage was 38%, which indicates a poor performance. The performance of the NTSS was rated as average on flexibility (score percent: 68%) and acceptability (score percent: 64%) attributes and poor on stability (score percentage: 33%), simplicity (score percentage: 57%), and representativeness (score percentage: 39%) attributes. About 65% of investigation forms were completed within 48 hours of notification date. Data quality was poor, as 41% of the core variables were missing.ConclusionsThe overall performance of the NTSS was poor. Most of the system attributes require improvement, including stability, simplicity, quality of data, and completeness of investigation. To improve the performance of NTSS, the following are recommended: capacity building of staff (focal points), strengthening NTSS through technical support and government funding to ensure its sustainability, establishing electronic investigation forms for improving the system data quality, and expansion of NTSS coverage to include all private health care facilities.  相似文献   
999.
1000.
Adipose-derived stem cells (ASCs) have the potential to enhance tendon repair via paracrine regulation of the inflammatory response to injury. Extracellular vesicles (EVs), which are secreted by ASCs, have shown promise in mediating this process. This study was designed to evaluate the effect of ASC EVs on early tendon healing using a mouse Achilles tendon injury and repair model. EVs were isolated from the conditioned medium of naïve and interferonγ-primed ASCs and applied to the repair site via a collagen sheet. Tendon healing was assessed in nuclear factor-κB (NF-κB)-luciferase reporter mice up to 7 days after suture repair. As anticipated, repair site NF-κB activity increased greater than twofold following tendon repair. Treatment with EVs from primed but not naïve ASCs effectively suppressed the response. Accordingly, the pro-inflammatory genes Il1b and Ifng were both dramatically increased in repaired tendons, while primed, but not naïve ASC EVs attenuated the response. Compared with control repairs, primed ASC EVs further reduced the rate of post-repair tendon gap formation and rupture and facilitated collagen formation at the injury site. Additional experiments demonstrated that EVs target macrophages and that primed ASC EVs were most effective in blocking macrophage NF-κB activity. Collectively, the findings of this study demonstrate that primed ASC EVs, similar to ASCs, attenuate the early tendon inflammatory response after injury via modulation of the macrophage inflammatory response. Statement of clinical significance: These findings introduce a new cell-free therapy, derived from stem cells, for tendon repair with the potential for improved therapeutic efficacy and safety. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:117–127, 2020  相似文献   
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