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81.
Gulay Bayramoglu Damla Gozen Gozde Ersoy V. Cengiz Ozalp K. Can Akcali M. Yakup Arica 《Journal of biomaterials science. Polymer edition》2014,25(7):657-678
The objective of the present study was to develop 2-hydroxypropyl methacrylate-co-polyethylene methacrylate [p(HPMA-co-PEG–MEMA)] hydrogels that are able to efficiently entrap doxorubicin for the application of loco-regional control of the cancer disease. Systemic chemotherapy provides low clinical benefit while localized chemotherapy might provide a therapeutic advantage. In this study, effects of hydrogel properties such as PEG chains length, cross-linking density, biocompatibility, drug loading efficiency, and drug release kinetics were evaluated in vitro for targeted and controlled drug delivery. In addition, the characterization of the hydrogel formulations was conducted with swelling experiments, permeability tests, Fourier transform infrared, SEM, and contact angle studies. In these drug-hydrogel systems, doxorubicin contains amine group that can be expected a strong Lewis acid–base interaction between drug and polar groups of PEG chains, thus the drug was released in a timely fashion with an electrostatic interaction mechanism. It was observed that doxorubicin release from the hydrogel formulations decreased when the density of cross-linking, and drug/polymer ratio were increased while an increase in the PEG chains length of the macro-monomer (i.e. PEG–MEMA) in the hydrogel system was associated with an increase in water content and doxorubicin release. The biocompatibility of the hydrogel formulations has been investigated using two measures: cytotoxicity test (using lactate dehydrogenase assay) and major serum proteins adsorption studies. Antitumor activity of the released doxorubicin was assessed using a human SNU398 human hepatocellular carcinoma cell line. It was observed that doxorubicin released from all of our hydrogel formulations which remained biologically active and had the capability to kill the tested cancer cells. 相似文献
82.
Betul Borku Uysal MD Hande Ikitimur MD Serap Yavuzer MD Baris Ikitimur MD Harun Uysal MD Mehmet Sami Islamoglu MD Erkan Ozcan MD Emre Aktepe MD Hakan Yavuzer MD Mahir Cengiz MD 《Journal of medical virology》2020,92(11):2648-2656
To recognize the period of exaggerated cytokine response in patients with coronavirus disease 2019 (COVID-19) pneumonia, and to describe the clinical outcomes of using tocilizumab as a treatment option. The data of 12 adult COVID-19 pneumonia patients who were followed in the inpatient clinics of Biruni University Medical Faculty Hospital (Istanbul, Turkey) were retrospectively analyzed. Diagnostic tests, laboratory examinations, clinical findings, and computed tomography of the thorax imaging results were evaluated. A dramatic laboratory and clinical improvement was observed in 83% (10 out of 12) of patients after tocilizumab. In 17% (2 out of 12) of our patients, short-term ventilator support was required in the intensive care unit. The longest hospital stay was 18 days. However, in the end, all of our patients were discharged home with good health. Although arterial oxygen saturations (87.58 ± 3.12%) dropped in room air in the pre-tocilizumab period, post-tocilizumab they normalized in all patients (94.42 ± 1%). None of them had fever after tocilizumab treatment and the levels of C-reactive protein (13.08 ± 12.89) were almost within normal limits. Eosinophil values were quite low at the time of diagnosis (10 ± 17.06), but increased significantly post-tocilizumab (155.33 ± 192.69). There is currently no proven treatment for COVID-19 induced by novel coronavirus SARS-CoV-2. Based on our experience with twelve adult COVID-19 pneumonia patients, we can say that tocilizumab, an IL-6 inhibitor, is more beneficial in preventing the damage caused by excessive cytokine response in the body if administered at the right time and provides clinical and radiological recovery. 相似文献
83.
Paraoxonase-1 is an esterase enzyme and it has 3 types of activity, namely paraoxonase, arylesterase, and diazoxonase. It has been reported that paraoxonase-1 deficiency is related to increased susceptibility to development of atherosclerosis and cardiovascular disease. The aim of this study was to investigate serum paraoxonase and arylesterase activities in children with iron deficiency anemia and vitamin B(12) deficiency anemia. Thirty children with iron deficiency anemia, 30 children with vitamin B(12) deficiency anemia, and 40 healthy children aged 6 months to 6 years were enrolled in this study. Serum paraoxonase and arylesterase activities were measured with a spectrophotometer by using commercially available kits. Mean paraoxonase and arylesterase activities in vitamin B(12) deficiency anemia group (103 ± 73 and 102 ± 41 U/L, respectively) were significantly lower than mean activities of control group (188 ± 100 and 147 ± 34 U/L, respectively; P < .001 for both) and iron deficiency anemia group (165 ± 103 and 138 ± 39 U/L, respectively; P < .05, P < .001), whereas there were no significant differences between iron deficiency anemia and control groups (P > .05). Paraoxonase and arylesterase activities significantly increased after treatment with vitamin B(12) in vitamin B(12) deficiency anemia; however, there were no significant changes in the activities of these enzymes after iron treatment in iron deficiency anemia group. Important correlations were found between vitamin B(12) levels and both paraoxonase and arylesterase activities (r = .367, P < .001; r = .445, P < .001). Our results suggest that vitamin B(12) deficiency anemia causes important reductions in paraoxonase and arylesterase activities, and after vitamin B(12) therapy the activities of these enzymes returned to near-normal levels. 相似文献
84.
The Toll-interleukin-1 receptor member SIGIRR regulates colonic epithelial homeostasis, inflammation, and tumorigenesis 总被引:4,自引:0,他引:4
Xiao H Gulen MF Qin J Yao J Bulek K Kish D Altuntas CZ Wald D Ma C Zhou H Tuohy VK Fairchild RL de la Motte C Cua D Vallance BA Li X 《Immunity》2007,26(4):461-475
Despite constant contact with the large population of commensal bacteria, the colonic mucosa is normally hyporesponsive to these potentially proinflammatory signals. Here we report that the single immunoglobulin IL-1 receptor-related molecule (SIGIRR), a negative regulator for Toll-IL-1R signaling, plays a critical role in gut homeostasis, intestinal inflammation, and colitis-associated tumorigenesis by maintaining the microbial tolerance of the colonic epithelium. SIGIRR-deficient (Sigirr(-/-)) colonic epithelial cells displayed commensal bacteria-dependent homeostatic defects, as shown by constitutive upregulation of inflammatory genes, increased inflammatory responses to dextran sulfate sodium (DSS) challenge, and increased Azoxymethane (AOM)+DSS-induced colitis-associated tumorigenesis. Gut epithelium-specific expression of the SIGIRR transgene in the SIGIRR-deficient background reduced the cell survival of the SIGIRR-deficient colon epithelium, abrogated the hypersensitivity of the Sigirr(-/-) mice to DSS-induced colitis, and reduced AOM+DSS-induced tumorigenesis. Taken together, our results indicate that epithelium-derived SIGIRR is critical in controlling the homeostasis and innate immune responses of the colon to enteric microflora. 相似文献
85.
Mihrimah Ozkan Mark Wang Cengiz Ozkan Richard Flynn Sadik Esener 《Biomedical microdevices》2003,5(1):61-67
In this paper, we review optical techniques used for micro-manipulation of small particles and cells in microfluidic devices. These techniques are based on the object's interaction with focused laser light (consequential forces of scattering and gradient). Inorganic objects including polystyrene spheres and organic objects including biological cells were manipulated and switched in and between fluidic channels using these forces that can typically be generated by vertical cavity surface emitting laser (VCSEL) arrays, with only a few mW optical powers. T-, Y-, and multi-layered X fluidic channel devices were fabricated by polydimethylsiloxane (PDMS) elastomer molding of channel structures over photolithographically defined patterns using a thick negative photoresist. We have also shown that this optical manipulation technique can be extended to smaller multiple objects by using an optically trapped particle as a handle, or an optical handle. Ultimately, optical manipulation of small particles and biological cells could have applications in biomedical devices for drug discovery, cytometry and cell biology research. 相似文献
86.
87.
Huseyin Cengiz Hediye Dağdeviren Cihan Kaya Ali Yeşil Sema Süzen Çaypınar 《Archives of gynecology and obstetrics》2014,289(3):609-614
Purpose
Almost 50 % of the patients experience moderate-to-severe pain during endometrial biopsy. The study aimed to examine the effectiveness of intrauterine lidocaine for relieving pain during endometrial biopsy.Methods
A randomised trial was conducted in 120 patients undergoing endometrial biopsy. Sixty-seven women were assigned to the paracervical block group and 53 were assigned to the intrauterine lidocaine group. The main outcome measure was pain intensity, measured using the visual analogue scale, during and after the procedure.Results
The groups were similar with regard to age, body mass index, gravidity, total number of previous vaginal deliveries, menopausal status, and uterine depth. The pain scores immediately after the procedure were similar in the groups (p = 0.079). However, the pain scores 30 min after the procedure were significantly lower in the intrauterine group than in the paracervical group (p = 0.0001).Conclusions
Compared to paracervical block, intrauterine lidocaine may be the preferred anaesthesia for endometrial biopsy, and it does not cause any serious complications. 相似文献88.
Cengiz Günay Jeremy R. Edgerton Su Li Thomas Sangrey Astrid A. Prinz Dieter Jaeger 《Neuroinformatics》2009,7(2):93-111
Neuronal recordings and computer simulations produce ever growing amounts of data, impeding conventional analysis methods
from keeping pace. Such large datasets can be automatically analyzed by taking advantage of the well-established relational
database paradigm. Raw electrophysiology data can be entered into a database by extracting its interesting characteristics
(e.g., firing rate). Compared to storing the raw data directly, this database representation is several orders of magnitude
higher efficient in storage space and processing time. Using two large electrophysiology recording and simulation datasets,
we demonstrate that the database can be queried, transformed and analyzed. This process is relatively simple and easy to learn
because it takes place entirely in Matlab, using our database analysis toolbox, PANDORA. It is capable of acquiring data from
common recording and simulation platforms and exchanging data with external database engines and other analysis toolboxes,
which make analysis simpler and highly interoperable. PANDORA is available to be freely used and modified because it is open-source
().
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
89.
Introduction: In this study we investigated the effect of crush and axotomy of phrenic nerves on oxidative stress and antioxidant enzyme activities in rat diaphragm muscle. Methods: The animals in the first group were not crushed or axotomized and served as controls. Phrenic nerves of the rats in the second and third groups were crushed or axotomized in the diaphragm muscle. Results: The malondialdehyde level increased in diaphragm muscles after both crush and axotomy. The antioxidant enzymes, such as superoxide dismutase, glutathione peroxidase, carbonic anhydrase, and catalase, decreased in diaphragm muscles after both crush and axotomy. Conclusions: Crushing or axotomizing the phrenic nerves may produce oxidative stress in the diaphragm muscle of the rat by increasing lipid peroxidation and decreasing antioxidant enzyme activities. Muscle Nerve, 2012 相似文献