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1.
Objectives:To assess low dose altepase outcome and safety in comparison with a standard-dose regimen for acute ischemic stroke treatment in Egyptian patients.Materials:An observational prospective cohort non-randomized single blinded study was carried out during the period from November 2017 to December 2018. Eighty Egyptian acute ischemic stroke patients, all eligible for intravenous alteplase, were subdivided into 2 groups (40 patients in each group). Patients were thrombolysed at a dose of 0.6 mg/kg in the first group and 0.9 mg/kg in the second group. Both groups were compared in regard to safety and outcome. Safety was expressed by the rate of symptomatic intracranial hemorrhage (SICH) and 3 months mortality, while outcome was expressed by favorable outcomes at three months (modified Rankin Scale [mRS] of 0 to 2).Results:In the first group, 69.2% (n=27) achieved favorable outcomes at 90 days compared with 64.1% (n=25) in the second group (p=0.631). Ninety-day mortality was 5% (n=2) in the first group versus 2.5% (n=1) in the second group (p=0.556). Symptomatic intracranial hemorrhage was noted in 3 patients in the second group and zero patients in the first group (p=0.077).Conclusion:Low-dose alteplase could be a practical alternative for Egyptian populations with acute ischemic stroke especially in 3 to 4.5 hours window.

Cerebrovascular stroke is the second death and the seventh disability leading cause worldwide.1 Tissue-type plasminogen activator (tPA) alteplase was the first medication approved by the Food and Drug Administration (FDA) for the acute ischemic stroke (AIS) treatment on June 1996, within 3 hours of stroke onset with a recommended dose of 0.9 mg/kg (maximum 90mg).2 In 2008, the safety of using alteplase within 3 to 4.5 hours of stroke onset was approved by the Safe Implementation of Treatments in Stroke International Stroke Thrombolysis Registry (SITS -ISTR)3 and the European Cooperative Acute Stroke Study (ECASS III).4 However, thrombolytic therapy use has not been widely adopted, especially in developing countries. The restricted time window (3 to 4.5 hours), intracerebral hemorrhage (ICH) risk and the drug high cost are major obstacles preventing its broad application.5 Coagulation and fibrinolysis responses differ among different races, which increase symptomatic intracerebral hemorrhage (SICH) risk with standard-dose alteplase6 in Asian populations, many Asian neurologists considered alteplase low dose to be a better alternative for ischemic stroke treatment. Many studies had been conducted in order to prove the efficacy and safety of Alteplase low dose.7-9 One of these studies was the Japan Alteplase Clinical Trial (J-ACT) conducted by Yamaguchi et al10 According to this study, using a 0.6 mg/kg dose of intravenous recombinant tissue plasminogen activator (rtPA) in Japanese patients was safe and effective. Despite the relatively stroke high rate among Egyptian populations, 963/100,000 inhabitants, only less than 1% of stroke patients receive intravenous thrombolysis. A major reason for this is the drug cost.11,12 Low-dose regimens (0.6 mg/kg) use will lower the economic burden of thrombolytic therapy in the community and will greatly promote the implementation of this therapy in Egypt. Our study aim was to assess the outcome and safety of alteplase low dose in comparison to the standard-dose regimen in AIS treatment in Egypt.  相似文献   
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Tumor cells upregulate myriad proteins that are important for pH regulation, resulting in the acidification of the extracellular tumor microenvironment (TME). Abnormal pH is known to dampen immune function, resulting in a worsened anti-tumor immune response. Understanding how extrinsic alterations in pH modulate the interactions between immune cells and tumors cells will help elucidate opportunities for new therapeutic approaches. We observed that pH impacts the function of immune cells, both natural killer (NK) and T cells, which is relevant in the context of a highly acidic TME. Decreased NK and T cell activity was correlated with decreasing pH in a co-culture immune cell-mediated tumor cell-killing assay. The addition of pH-modulating drugs cariporide, lansoprazole, and acetazolamide to the co-culture assay was able to partially mitigate this dampened immune cell function. Treatment of colorectal cancer (CRC) cells with NHE1 inhibitor cariporide increased CRC cell-secreted cytokines involved in immune cell recruitment and activation and decreased cytokines involved in epithelial-mesenchymal transition (EMT). Cariporide treatment also decreased CRC cell shed TRAIL-R2, TRAIL-R3, and PD-L1 which is relevant in the context of immunotherapy. These experiments can help inform future investigations into how the pH of the tumor microenvironment may be extrinsically modulated to improve anti-tumor immune response in solid tumors such as colorectal cancer.  相似文献   
4.
BACKGROUND: Ghrelin, a 28-amino-acid gastric peptide hormone, has an appetite-stimulating effect and controls the energy balance. Serum ghrelin levels inversely correlate with body mass index. Recently, several papers reported the ethnic difference in the ghrelin levels. To our knowledge, however, no studies have compared the serum ghrelin levels between Caucasians in the USA and the Japanese in Japan. METHODS: We conducted a cross-sectional study of 189 men 40-49 years of age (91 US Caucasians in the U.S. and 98 Japanese in Japan) to examine serum ghrelin levels and metabolic and other factors. RESULTS: Serum ghrelin levels correlated with waist circumferences and lipid profiles among Caucasian Americans and the Japanese. Serum ghrelin levels were significantly higher among Caucasian Americans than among the Japanese (904.5 (632.0, 1132.0) pg/mL, 508.0 (399.0, 1378.3) pg/mL (median and 95% confidence interval), respectively, P < 0.01), although Caucasian Americans were much more obese (BMI: 26.9 +/- 3.3 kg/m(2) versus 23.3 +/- 3.1 kg/m(2) respectively, P < 0.01). The ethnic difference remained after adjusting for metabolic factors, smoking status, and other factors (P < 0.01). CONCLUSIONS: We have shown in our population-based study that serum ghrelin levels among men aged 40-49 are significantly higher in Caucasian Americans than in the Japanese in Japan. Reasons for the ethnic difference in the ghrelin levels are largely unknown and warrant further investigation.  相似文献   
5.
The endovascular treatment of aortic arch aneurysms is a relatively new technique and is associated with significant surgical and anesthetic challenges. We report a case of a 77-year-old patient with an aortic arch aneurysm at the level of the isthmus, measuring 4.9 × 6.5 cm. The aneurysm involved the origin of the left subclavian and vertebral arteries. The arch was of the bovine type and the left vertebral artery came directly off the aorta. The patient underwent an uneventful open left carotid-to-subclavian bypass several days before the aortic repair. During the endovascular surgery, a stent-graft was deployed just distal to the innominate trunk. Endoleak was noted at the inferior aspect of the stent-graft, which failed to seal with placement of an extension stent-graft. The surgeon then chose to employ a Palmaz stent, to seal the endoleak. Balloon expansion in the ascending aorta was required in order to properly seat the Palmaz stent. Overdrive pacing at a rate of 220 beats·min?1, which lowered the systolic blood pressure (SBP) to 40s mmHg was used during this process after connecting the patient to a Zoll defibrillator with external pads. The Palmaz stent was successfully deployed at the proximal end of the previously deployed stent-graft, using a Tyshak balloon. The patient reverted to normal sinus rhythm with no evidence of ischemia at the conclusion of the overdrive pacing. No endoleak was appreciated after the Palmaz stent was placed.  相似文献   
6.

Purpose

The purpose of this study is to evaluate quantitative changes in diffusion tensor imaging (DTI) tractography and fractional anisotropy (FA) of the pons along with clinical correlation, in patients who receive re-irradiation for progressive diffuse intrinsic pontine glioma (DIPG).

Methods

A retrospective case review of children with progressive DIPG who received re-irradiation at our institution from 2007 to 2011 after approval from the Institutional Review Board was performed. Tractography analysis and FA were analyzed pre and post-re-irradiation, and correlation with clinical features and MR imaging was performed.

Results

DTI analysis showed reduced values of FA on tumor progression. Increase in the FA values was noted after re-irradiation in these patients. This correlated with clinical improvement. These changes were concordant with the 3D tractography analysis which showed better visualization of the corticospinal tracts as they course through brainstem and posterior transverse pontine fibers following re-irradiation.

Conclusion

Serial changes in the FA values using DTI could provide clinically more correlative information in patients with progressive DIPG, who receive re-irradiation. Though the use and results of this modality has been reported in the newly diagnosed DIPG before, evaluation of DTI in children who receive re-irradiation for progressive DIPG has not been reported earlier. Though limited by the small sample size and treatment variability, this study for the first time shows the preliminary experience, potential, and likely efficacy of complementing DTI analysis to routine neuroimaging also in patients re-irradiated for progressive DIPG to better assess treatment response.  相似文献   
7.
Osteopontin (OPN), a bone‐related protein, is present within the atherosclerotic plaques, most strikingly in calcified plaques. Valvular calcifications are accepted as a part of the spectrum of atherosclerosis and are associated with atherosclerotic calcification in the coronary arteries. The study aimed to evaluate the association of plasma OPN with the presence and extent of coronary stenosis, mitral annular calcification (MAC), and aortic valve sclerosis in stable angina patients. We studied 120 subjects who underwent coronary angiography because of ischemic chest pain. Coronary artery disease (CAD) was defined as ≥50% stenosis in ≥1 coronary artery. MAC and aortic valve sclerosis were detected by echocardiography. Lipid profile, high sensitive C‐reactiveprotein (hsCRP), and OPN were measured in all studied subjects. Patients with CAD had increased plasma OPN when compared with those without CAD (P<0.001). Plasma OPN levels were significantly positively correlated with atherogenic lipid profile, hsCRP, MAC grading, aortic valve sclerosis grading, and the number of stenosed coronary vessels in CAD patients. In multivariate analysis, OPN was an independent predictor of CAD (P=0.01), MAC (P=0.01), and aortic valve sclerosis (P=0.04). In conclusion, OPN is an independent predictor of MAC and aortic valve sclerosis. Plasma OPN levels reflect the extent of coronary stenosis and can be used as a biomarker to identify patients with coronary atherosclerosis. J. Clin. Lab. Anal. 24:201–206, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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Epidermal growth factor receptor (EGFR) is frequently overexpressed in esophageal carcinoma and its precursor lesions. To gain insights into how EGFR overexpression affects cellular functions in primary human esophageal cells, we performed gene expression profiling and identified insulin-like growth factor-binding protein (IGFBP)-3 as the most up-regulated gene. IGFBP-3 regulates cell proliferation through both insulin-like growth factor-dependent and independent mechanisms. We found that IGFBP-3 mRNA and protein expression was increased in EGFR-overexpressing primary and immortalized human esophageal cells. IGFBP-3 was also up-regulated in EGFR-overexpressing cells in organotypic culture and in EGFR transgenic mice. Furthermore, IGFBP-3 mRNA was overexpressed in 80% of primary esophageal squamous cell carcinomas and 60% of primary esophageal adenocarcinomas. Concomitant up-regulation of EGFR and IGFBP-3 was observed in 60% of primary esophageal squamous cell carcinomas. Immunohistochemistry revealed cytoplasmic localization of IGFBP-3 in the preponderance of preneoplastic and neoplastic esophageal lesions. IGFBP-3 was also overexpressed in esophageal cancer cell lines at both mRNA (60%) and protein (40%) levels. IGFBP-3 secreted by cancer cells was capable of binding to insulin-like growth factor I. Functionally, epidermal growth factor appeared to regulate IGFBP-3 expression in esophageal cancer cell lines. Finally, suppression of IGFBP-3 by small interfering RNA augmented cell proliferation, suggesting that IGFBP-3 may inhibit tumor cell proliferation as a negative feedback mechanism. In aggregate, we have identified for the first time that IGFBP-3 is an aberrantly regulated gene through the EGFR signaling pathway and it may modulate EGFR effects during carcinogenesis.  相似文献   
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