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41.
Masaeli E Morshed M Rasekhian P Karbasi S Karbalaie K Karamali F Abedi D Razavi S Jafarian-Dehkordi A Nasr-Esfahani MH Baharvand H 《Journal of biomedical materials research. Part A》2012,100(7):1907-1918
A critical element in tissue engineering involves the fabrication of a three-dimensional scaffold. The scaffold provides a space for new tissue formation, supports cellular ingrowth, and proliferation and mimics many roles of the extracellular matrix. Poly(3-hydroxybutyrate) (PHB) is the most thoroughly investigated member of the polyhydroxyalkanoates (PHAs) family that has various degrees of biocompatibility and biodegradability for tissue engineering applications. In this study, we fabricated PHB scaffolds by utilizing electrospinning and salt-leaching procedures. The behavior of monkey epithelial kidney cells (Vero) and mouse mesenchymal stem cells (mMSCs) on these scaffolds was compared by the MTS assay and scanning electron microscopy. Additionally, this study investigated the mechanical and physical properties of these scaffolds by measuring tensile strength and modulus, dynamic contact angle and porosity. According to our results, the salt-leached scaffolds showed more wettability and permeability, but inferior mechanical properties when compared with nanofibrous scaffolds. In terms of cell response, salt-leached scaffolds showed enhanced Vero cell proliferation, whereas both scaffolds responded similarly in the case of mMSCs proliferation. In brief, nanofibrous scaffolds can be a better substrate for cell attachment and morphology. 相似文献
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Shahram Akhlaghpoor Alireza Aziz-Ahari Mahasti Amoui Shahnaz Tolooee Hossein Poorbeigi Shahab Sheybani 《World journal of gastroenterology : WJG》2012,18(37):5249-5259
AIM:To introduce the combination method of radio-chemoembolization for the treatment of selected hepatic metastases. METHODS:Twenty patients with biopsy proven hepatic metastases were selected from those who underwent transarterial radiochemoembolization, a novel combination protocol, between January 2009 and July 2010. Patients had different sources of liver metastasis. The treatment included transarterial administration of three chemotherapeutic drugs (mitomycin, doxorubicin and cisplatin), followed by embolization with large (50-150 μm) radioisotope particles of chromic 32P. Multiphasiccomputer tomography or computer tomography studies, with and without contrast medium injections, were performed for all patients for a short-term period before and after the treatment sessions. The short-term effec-tiveness of this procedure was evaluated by modified response evaluation criteria in solid tumors (mRECIST), which also takes necrosis into account. The subjective percentage of necrosis was also assessed. The response evaluation methods were based on the changes in size, number, and the enhancement patterns of the lesions between the pre-and post-treatment imaging studies. RESULTS:Patients had liver metastasis from colorectal carcinomas, breast cancer, lung cancer and carcinoid tumors. The response rate based on the mRECIST criteria was 5% for complete response, 60% for partial response, 10% for stable disease, and 25% for progressive disease. Regarding the subjective necrosis percentage, 5% of patients had complete response, 50% had partial response, 25% had stable disease, and 20% had progressive disease. Based on traditional RECIST criteria, 3 patients (15%) had partial response, 13 patients (65%) had stable disease, and 4 patients (20%) had disease progression. In most patients, colorectal carcinoma was the source of metastasis (13 patients). Based on the mRECIST criteria, 8 out of these 13 patients had partial responses, while one remained stable, and 5 showed progressive disease. We also had 5 cases of breast cancer metastasis which mostly remained stable (4 cases), with only one partial response after the procedure. Six patients had bilobar involvement; three of them received two courses of radiochemoembolization. The follow up imaging study of these patients was performed after the second ses-sion. In the studied patients there was no evidence of extrahepatic occurrence, including pulmonary radioac-tive deposition, which was proven by Bremsstrahlung scintigraphy performed after the treatment sessions. For the short-term follow-ups for the 2 mo after the therapy, no treatment related death was reported. The mostly common side effect was post-embolizationsyndrome, presented as vomiting, abdominal pain, and fever. Nineteen (95%) patients experienced this syndrome in different severities. Two patient had ascites (with pleural effusion in one patient) not related to hepatic failure. Moreover, no cases of acute liver failure, hepatic infarction, hepatic abscess, biliary necrosis, tumor rupture, surgical cholecystitis, or non-targeted gut embolization were reported. Systemic toxicities such as alopecia, marrow suppression, renal toxicity, or cardiac failure did not occur in our study group. CONCLUSION:Radiochemoembolization is safe and effective for selected hepatic metastases in a short-term follow-up. Further studies are required to show the long-term effects and possible complications of this approach. 相似文献
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Hossein Khorramdelazad Gholamhossein Hassanshahi Behzad Nasiri Ahmadabadi Mohammad Kazemi Arababadi 《Hepatitis monthly》2012,12(11)
Background
The transforming growth factor-β (TGF-β) is an important cytokine with anti-inflammatory properties.Objectives
The main purpose of this study was to compare the serum levels of TGF-β in a group of chronic HBV infected (CHB) patients as well as healthy individuals from South-East of Iran.Patients and Methods
Sixty patients with CHB as well as sixty healthy individuals were enrolled in the study. ELISA technique was applied to measure the serum levels of TGF-β in both groups.Results
Our results revealed that the serum levels of TGF-β were significantly increased in CHB patients in compare to healthy controls.Conclusions
According to this result, it may be concluded that high serum levels of TGF-β may be a mechanism by which immune response against HBV is suppressed. 相似文献47.
Niloufar Rasaei Atieh Mirzababaei Hana Arghavani Somayeh Tajik Seyed Ali Keshavarz Mir Saeed Yekaninejad Hossein Imani Khadijeh Mirzaei 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(6):1147-1153
Aim
Metabolically Healthy Obese (MHO) is called to obese people that their insulin sensitivity, lipid profiles and inflammatory profiles are favorable, and there are no signs of hypertension and cardio-metabolic diseases. The metabolically unhealthy obese (MUHO) is the opposite. A Body Shape Index (ABSI) is a marker to identifying abdominal obesity that is derived from weight, height and waist circumference (WC). Several studies have reported ABSI is associated with diabetes, metabolic syndrome, hypertension and higher mortality rate.Materials and methods
A total of 305 overweight and obese women were included in the current comparative cross-sectional study. Body composition was measured using body composition analyzer. Blood samples were obtained. The usual food intake of evaluated through the use of a semi-quantitative food frequency questionnaire.Results
The results of this study revealed that there is a significant relationship between ABSI and MHO and MUHO (p?=?0.04) and area under the ROC curve was 0.60. Also there is a significant relationship between BMI, fat mass index (FMI), free fat mass index (FFMI), neck circumference (NC), WC, fat mass (FM) and metabolic healthy status (MHS). The largest area under the ROC curve belonged to NC, WC, FM and BMI (0.66).Conclusion
The findings of this study suggest that there is a significant relationship between ABSI, BMI, FMI, FFMI, NC, WC, FM and MHS. The largest area under the ROC curve was related to the NC, WC, FM and BMI not ABSI, that means NC, WC, FM and BMI have maximum sensitivity and specificity. 相似文献48.
John Xuefeng Jiang Daniel Polsky Jeff Littlejohn Yuchen Wang Hossein Zare Ge Bai 《Journal of general internal medicine》2022,37(14):3577
BACKGROUNDThe Hospital Price Transparency Final Rule, effective January 1, 2021, requires hospitals to post online a machine-readable file that includes payer-specific negotiated commercial prices for all services. The regulation aims to improve the affordability of hospital care by promoting price competition. However, a low compliance level among hospitals would compromise the operational effectiveness of this regulation. Understanding hospitals’ compliance status to the regulation has important implications for its enforcement effort and effectiveness assessment.OBJECTIVETo analyze nationwide hospitals’ compliance status to the Hospital Price Transparency Rule.DESIGNCross-sectional observational study.PARTICIPANTSA total of 3558 Medicare-certified general acute-care hospitals were examined.MAIN MEASURESA binary compliance rating was generated by using data collected by Turquoise Health. “Noncompliance” means that no machine-readable file was posted or the posted file contains no commercial negotiated prices. “Compliance” means that a machine-readable file was posted with commercial negotiated prices for at least one insurance plan.KEY RESULTSAs of June 1, 2021, 55% of the 3558 Medicare-certified general acute-care hospitals we examined had not posted a machine-readable file containing commercial negotiated prices. Wide variations of compliance existed across states and hospital referral regions. A hospital’s compliance status is strongly associated with the average compliance status of peer hospitals in the same market. Hospitals with greater IT preparedness, for-profit hospitals, system-affiliated hospitals, large hospitals, and non-urban hospitals had greater compliance. More concentrated hospital markets had greater average compliance.CONCLUSIONSHospitals take into consideration the behavior of their peers in the same market when making price disclosure decisions. Compliant hospitals are likely to have better IT preparedness, more financial resources and personnel expertise to mitigate the cost required for the implementation of the Price Transparency Rule. The compliance cost, therefore, might be a barrier for some hospitals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-07237-y. 相似文献
49.
Role of CXCR2/CXCR2 ligands in vascular remodeling during bronchiolitis obliterans syndrome 下载免费PDF全文
Belperio JA Keane MP Burdick MD Gomperts B Xue YY Hong K Mestas J Ardehali A Mehrad B Saggar R Lynch JP Ross DJ Strieter RM 《The Journal of clinical investigation》2005,115(5):1150-1162
Angiogenesis and vascular remodeling support fibroproliferative processes; however, no study has addressed the importance of angiogenesis during fibro-obliteration of the allograft airway during bronchiolitis obliterans syndrome (BOS) that occurs after lung transplantation. The ELR(+) CXC chemokines both mediate neutrophil recruitment and promote angiogenesis. Their shared endothelial cell receptor is the G-coupled protein receptor CXC chemokine receptor 2 (CXCR2). We found that elevated levels of multiple ELR(+) CXC chemokines correlated with the presence of BOS. Proof-of-concept studies using a murine model of BOS not only demonstrated an early neutrophil infiltration but also marked vascular remodeling in the tracheal allografts. In addition, tracheal allograft ELR(+) CXC chemokines were persistently expressed even in the absence of significant neutrophil infiltration and were temporally associated with vascular remodeling during fibro-obliteration of the tracheal allograft. Furthermore, in neutralizing studies, treatment with anti-CXCR2 Abs inhibited early neutrophil infiltration and later vascular remodeling, which resulted in the attenuation of murine BOS. A more profound attenuation of fibro-obliteration was seen when CXCR2(-/-) mice received cyclosporin A. This supports the notion that the CXCR2/CXCR2 ligand biological axis has a bimodal function during the course of BOS: early, it is important for neutrophil recruitment and later, during fibro-obliteration, it is important for vascular remodeling independent of neutrophil recruitment. 相似文献
50.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献