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81.
OBJECTIVE: To assess which subjective scale, the visual analogue scale (VAS), the Borg CR10 (Borg) scale, or the Likert scale (LS), if any, is decidedly more reproducible and sensitive to change in the assessment of symptoms. DESIGN: Prospective clinical study. SETTING: Exercise laboratory. PARTICIPANTS: Twenty-three physically active male subjects (mean +/- SD age of 30 +/- 4 years old) were recruited. INTERVENTION: Each subject attended the exercise laboratory on four occasions at intervals of 1 week. Three subjective scales were used: (1) the VAS (continuous scale); (2) the Borg scale (12 fixed points); and (3) the Likert scale (LS; 5 fixed points). Four identical submaximal tests were given (2 min at 60% maximum oxygen uptake [VO(2)max] and 6 min at 70% VO(2)max). Two tests were undertaken to assess the reproducibility of scores that were obtained with each subjective scale. Two other tests were undertaken to assess the sensitivity of each scale to a change in symptom perception: a double-blind treatment with propranolol, 80 mg, (ie, active therapy; to increase the sensation of breathlessness and general fatigue during exercise) or matching placebo. The subjective scale scores were measured at 1 min 30 s, 5 min 30 s, and 7 min 15 s of exercise. Reproducibility was defined as the proportion of total variance (ie, between-subject plus within-subject variance) explained by the between-subject variance given as a percentage. Sensitivity was defined as the effect of the active drug therapy over the variation within subjects. RESULTS: Overall, the VAS performed best in terms of reproducibility for breathlessness and general fatigue, with reproducibility coefficients as high as 78%. For sensitivity, the VAS was best for breathlessness (ratio, 2.7) and the Borg scale was most sensitive for general fatigue (ratio, 3.0). The relationships between the respective psychological and physiologic variables were reasonably stable throughout the testing procedure, with overall typical correlations of 0.73 to 0.82 CONCLUSION: This study suggests that subjective scales can reproducibly measure symptoms during steady-state exercise and can detect the effect of a drug intervention. The VAS and Borg scales appear to be the best subjective scales for this purpose. 相似文献
82.
A Moscho O Orwar D T Chiu B P Modi R N Zare 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(21):11443-11447
We report here a rapid evaporation method that produces in high yield giant unilamellar vesicles up to 50 microns in diameter. The vesicles are obtained after only 2 min and can be prepared from different phospholipids, including L-alpha-phosphatidylcholine (lecithin), dipalmitoleoyl L-alpha-phosphatidylcholine, and beta-arachidonoyl gamma-palmitoyl L-alpha-phosphatidylcholine. Vesicles can be produced in distilled water and in Hepes, phosphate, and borate buffers in the pH range of 7.0 to 11.5 with ionic strengths up to 50 mM. The short preparation time allows encapsulation of labile molecular targets or enzymes with high catalytic activities. Cell-sized proteoliposomes have been prepared in which gamma-glutamyltransferase (EC 2.3.2.2) was functionally incorporated into the membrane wall. 相似文献
83.
Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion 总被引:1,自引:0,他引:1 下载免费PDF全文
Strömberg A Ryttsén F Chiu DT Davidson M Eriksson PS Wilson CF Orwar O Zare RN 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(1):7-11
A method for cell–cell and cell–liposome fusion at the single-cell level is described. Individual cells or liposomes were first selected and manipulated either by optical trapping or by adhesion to a micromanipulator-controlled ultramicroelectrode. Spatially selective fusion of the cell–cell or cell–liposome pair was achieved by the application of a highly focused electric field through a pair of 5-μm o.d. carbon-fiber ultramicroelectrodes. The ability to fuse together single cells opens new possibilities in the manipulation of the genetic and cellular makeup of individual cells in a controlled manner. In the study of cellular networks, for example, the alteration of the biochemical identity of a selected cell can have a profound effect on the behavior of the entire network. Fusion of a single liposome with a target cell allows the introduction of the liposomal content into the cell interior as well as the addition of lipids and membrane proteins onto the cell surface. This cell–liposome fusion represents an approach to the manipulation of the cytoplasmic contents and surface properties of single cells. As an example, we have introduced a membrane protein (γ-glutamyltransferase) reconstituted in liposomes into the cell plasma membrane. 相似文献
84.
Wu H Wheeler A Zare RN 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(35):12809-12813
An integrated microfluidic device has been fabricated for analyzing the chemical contents of a single cell (chemical cytometry). The device is designed to accomplish four different functions: (i) cell handling, (ii) metering and delivering of chemical reagents, (iii) cell lysis and chemical derivatization, and (iv) separating derivatized compounds and detecting them by laser-induced fluorescence. These functions are accomplished with only two valves, formed by multilayer soft lithography. A new kind of three-state valve and a picopipette are described; these elements are crucial for minimizing the reaction volume and ensuring optimal shape of the channel for electrophoresis injection. By using these valves, a reaction volume of approximately 70 pl is achieved for the lysis and derivitization of the contents of a single Jurkat T cell (approximately 10 microm diameter). As a demonstration of the use of this integrated microfluidic device, electropherograms of amino acids from individual Jurkat T cells are recorded and compared with those collected from a multiple-cell homogenate. 相似文献
85.
Mehrdad Asghari Estiar Rezvan Esmaeili Ali-Akbar Zare Leila Farahmand Hassan Fazilaty Ali Zekri Narges Jafarbeik-Iravani Keivan Majidzadeh-A 《Clinical and experimental medicine》2017,17(4):547-553
Carcinoembryonic antigen (CEA) family members play important roles in malignancies and are introduced as biomarkers in different types of cancers. Among them CEACAM19 (CEAL1) gene, a new member of the CEA family, remains to be fully elucidated. The aim of this study was investigating the mRNA expression level of CEACAM19 in tumor samples of breast cancer patients compared to breast tissue of normal individuals. We evaluated the expression level of this gene in 75 breast tumors by using real-time quantitative PCR. Also, we studied the correlation between CEACAM19 expression and clinicopathological features and hormone receptors status, including estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 of patients. Out of the enrolled patients, six of them (7.9%) showed low expression, ten (13.2%) showed normal expression and 59 (77.6%) showed high expression of CEACAM19. There was a significant correlation between high expression of CEACAM19 gene in tumor samples compared to normal tissues (P = 0.039). No significant correlation was seen between clinicopathological factors and disease-free survival with mRNA levels of CEACAM19 in tumor samples, while the difference between the expression of CEACAM19 in ER/PR-positive and ER/PR-negative breast cancer patients was statistically significant (P = 0.046). In conclusion, CEACAM19 showed high expression in tumor samples compared to normal mammary tissue. In addition, CEACAM19 may represent as a novel therapeutic target in certain subgroups of breast cancer patients such as ER/PR-negative. Critical roles of CEA proteins in tumor progression may nominate them as robust potential targets for therapeutic intervention in near future. 相似文献
86.
Mehdi Khaksari Fatemeh Zare Mehrjerdi Mohammad Ebrahim Rezvani Fatemeh Safari Aghdas Mirgalili Somayeh Niknazar 《The journal of physiological sciences : JPS》2017,67(1):163-171
Remote ischemic preconditioning (RIPC) is an intriguing approach which exposes a remote organ/tissue to a non-lethal transient ischemia/reperfusion (I/R) in order to potentiate the resistance of the desired organ/tissue against the next unwanted I/R. It has been suggested that RIPC exerts its effect through neuronal and hormonal pathways. The underlying mechanisms of RIPC are obscure and should be elucidated. In this study, we induced RIPC in mice using 3 cycles of 5 min ischemia alternating with 5 min reperfusion of the left renal artery. Renal failure was induced in mice by intra-peritoneal (i.p.) injection of 200 mg/kg body weight of gentamicin twice per day for 4 consecutive days. Global hippocampal ischemia reperfusion (I/R) was performed by bilateral carotid artery occlusion for 20 min followed by reperfusion for 72 h. Moreover, the retention trial of passive avoidance test was determined 72 h after global ischemia. Histopathological changes of hippocampus neurons were observed using Nissl staining to detect neuronal loss. Finally, terminal deoxynucleotidyl transferase mediated dUTP nick end-labeling (TUNEL) was performed to assess the status of apoptotic cells in the hippocampus. The results of this study suggest that renal ischemic preconditioning is a good candidate for prevention of I/R-induced hippocampal injury. However, RRPC (remote renal preconditioning) failed to exert a neuroprotective effect in mice with renal failure (RF), indicating the probable role of a humoral factor which is released from kidneys in response to ischemia. In agreement with this hypothesis, treatment of mice with rhEPO (5000 IU/kg intraperitoneal) before induction of RRPC restored the neuroprotective effects of RRPC in RF mice. Accordingly, it is plausible to expect that erythropoietin is released from kidneys to act as a mediator for RRPC-induced neuroprotective effects. Renal ischemic preconditioning prevents I/R-induced hippocampal injury. In contrast, renal failure hampers protective effects of RRPC, while exogenous administration of erythropoietin (EPO) significantly prevents the inhibiting effects of renal failure. 相似文献
87.
Pour-Ghaz Issa Heckle Mark R. Maturana Miguel Seitz Michael P. Zare Pegah Khouzam Rami N. Kabra Rajesh 《Current treatment options in cardiovascular medicine》2022,24(4):41-59
Current Treatment Options in Cardiovascular Medicine - Percutaneous left atrial appendage closure (LAAC) with WATCHMAN (Boston Scientific Inc.) has emerged as a viable non-pharmacological... 相似文献
88.
Mohammad Ali Nilforoushzadeh Maryam Heidari-Kharaji Mehrak Zare Sona Zare Batool Baiat Tork Fariba Jaffary 《Journal of diabetes investigation.》2021,12(6):1112-1117
A severe complication associated with diabetes is diabetic foot ulcer (DFU). Most patients with DFU require amputation. Although treatment of non-healing diabetic ulcers is challenging, the use of novel therapies can be effective. In this report, we present the case of a woman with type 2 diabetes with DFU-related osteomyelitis, who was treated with a combination therapy of trichloroacetic acid, calcium alginate and foam dressings, human autologous fibroblast injection, and a fibroblast cell-seeded collagen scaffold. The results showed the positive effects of combination therapy on DFU. In the initial treatment, the wound area was measured to be 14 × 7 cm2, with a depth of 4 cm. After 6 months, the wound was measured to be 1.5 cm2, showing a 90% reduction of the wound area. Overall, this combination therapy was highly effective in the treatment of DFU-related osteomyelitis, and could markedly prevent amputation among DFU patients. 相似文献
89.
Neda Shahmohammadibeni Simin Rahimi-Aliabadi Javad Jamshidi Babak Emamalizadeh Hossein Ali Shahmohammadibeni Alireza Zare Bidoki Haleh Akhavan-Niaki Hajar Eftekhari Shokoufeh Abdollahi Mahmoud Shekari Khaniani Mahnaz Shahmohammadibeni Atena Fazeli Marzieh Motallebi Shaghayegh Taghavi Azadeh Ahmadifard Amir Ehtesham Shafiei Zarneh Monavvar Andarva Tahereh Dadkhah Ehteram Khademi Elham Alehabib Mahnoosh Rahimi Abbas Tafakhori Minoo Atakhorrami Hossein Darvish 《Neurological sciences》2016,37(5):731-736
Parkinson’s disease (PD) is the second most prevalent neurodegenerative disorder. Both genetic and environmental factors are involved in the etiology of the disease. Many studies have revealed the susceptibility genes and variations for PD which need further confirmation. Here we evaluated the association of variations in SNCA, HUSEYO and CSMD1 genes with PD. A case–control study was conducted with 489 PD patients and 489 healthy controls. DNA was extracted from peripheral blood of all subjects and rs356220 and rs11931074 in SNCA, rs2338971 in HUSEYO and rs12681349 in CSMD1 were genotyped using PCR–RFLP method. The genotypes and allele frequencies were significantly different between case and control groups for rs356220, rs11931074 and rs2338971 but not for rs12681349. We provided further evidence that rs356220 is associated with increased risk of PD supporting previous studies in Caucasian-based and Japanese populations. The association of rs11931074 with decreased risk of PD was also significant. This study revealed the first evidence of the association of rs2338971 with increased risk of PD in the Iranian population. Nevertheless, these findings need further validation via more replication studies. 相似文献
90.