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Background: The efficacy of human recombinant erythropoietins (rHuEPOs) in the treatment of anemia with different etiologies is proven. Development of biosimilar rHuEPO products with lower cost and wider availability is important for the care of anemic patients. Objective: The aim of the present study was to determine the bioequivalence and safety of a biosimilar rHuEPO (Pastopoitin®) and compare it with the innovator product Eprex®, as a standard rHuEPO. Methods: One hundred and seven anemic patients on stable hemodialysis were recruited to this randomized double-blind comparative trial and assigned to either subcutaneous Pastopoitin (n = 50) or Eprex (n = 57). Each study group received rHuEPO at a dose of 80–120 IU/kg/week in 2–3 divided doses for a period of 3 months. Hematologic parameters including Hemoglobin, hematocrit, RBC, EBC, platelet, MCV, MCH and MCHC were checked every 2 weeks. Blood iron, ferritin, TIBC, creatinine, BUN and electrolytes (Na, K, Ca and P) were evaluated monthly over the 3 months. Results: A significant increase in hemoglobin, hematocrit and RBC was observed by the end of study in both Pastopoitin and Eprex groups (p < 0.001). However, these factors were not significantly different between the groups, neither at baseline nor at the end of study (p > 0.05). Likewise, the groups were comparable regarding MCV, MCH, MCHC, iron, ferritin, TIBC, creatinine, BUN and electrolytes at baseline as well as at the end of trial. Adverse events were not serious and occurred with the same frequency in the study groups. Conclusion: Pastopoitin showed comparable efficacy and safety profile with Eprex in anemic patients on hemodialysis. Hence, Pastopoitin may be considered as a rHuEPO with a lower cost and wider availability compared with the innovator product Eprex.  相似文献   
184.
Objective: Efficacy of the conventional- versus high-dose vancomycin regimen in patients with acute bacterial meningitis was compared.

Methods: In a randomized clinical trial 44 patients with acute bacterial meningitis were randomly assigned to the conventional- or high-dose vancomycin groups. Clinical and laboratory parameters were used for evaluation of response to the treatment regimens.

Results: In the high-dose group, leukocytosis and fever resolved significantly faster than those in the conventional group. Furthermore, the length of hospitalization was shorter and Glasgow Coma Scale at the end of 10th day was significantly lower in the high dose compared to the conventional group. Trend of creatinine clearance changes did not differ significantly between the two groups.

Conclusion: In comparison to the conventional-dose regimen, the high-dose vancomycin regimen was associated with significantly more favorable clinical response without increase in the incidence of nephrotoxicity in patients with acute bacterial meningitis.  相似文献   

185.
Stroke is the major leading cause of death and severe long-term disability worldwide. The consequences of stroke, aside from diminished survival, have a significant impact on an individual''s capability in maintaining self-autonomy and life satisfaction (LS). Thus, this study aimed to assess LS and other specific domains of LS in stroke survivors following their first-ever stroke, and to describe the relationship using socio-demographic and stroke-related variables.This study recruited 376 stroke survivors (244 men and 132 women, mean age: 57 years) 1 year following stroke. Data on participants’ LS (measured using the Life Satisfaction Questionnaire [LiSat-11]), socio-demographics, and stroke-related variables were collected.Univariate analysis showed that LS and the 10 specific domains were not associated with the patients’ gender or stroke type; however, age at onset, marital status, and vocational situation were significantly associated with some domains in LiSat-11 (Spearman''s rho = 0.42–0.87; all P < 0.05). Logistic regression revealed that verbal and cognitive dysfunction were the most negative predictors of LS (odds ratio 4.1 and 3.7, respectively).LS is negatively affected in stroke survivors 1 year post onset. The results indicate that recovering social engagement is a positive predictor of higher LS in stroke survivors. More importantly, the findings revealed that cognitive and verbal dysfunctions were the most prominent negative predictors of the overall gross level of LS. Multidisciplinary rehabilitation for stroke survivors is therefore critical.  相似文献   
186.
Copy number heterogeneity is a prominent feature within tumors. The molecular basis for this heterogeneity remains poorly characterized. Here, we demonstrate that hypoxia induces transient site-specific copy gains (TSSGs) in primary, nontransformed, and transformed human cells. Hypoxia-driven copy gains are not dependent on HIF1α or HIF2α; however, they are dependent on the KDM4A histone demethylase and are blocked by inhibition of KDM4A with a small molecule or the natural metabolite succinate. Furthermore, this response is conserved at a syntenic region in zebrafish cells. Regions with site-specific copy gain are also enriched for amplifications in hypoxic primary tumors. These tumors exhibited amplification and overexpression of the drug resistance gene CKS1B, which we recapitulated in hypoxic breast cancer cells. Our results demonstrate that hypoxia provides a biological stimulus to create transient site-specific copy alterations that could result in heterogeneity within tumors and cell populations. These findings have major implications in our understanding of copy number heterogeneity and the emergence of drug resistance genes in cancer.  相似文献   
187.
Curve of left ventricular (LV) volume changes throughout the cardiac cycle is a fundamental parameter for clinical evaluation of various cardiovascular diseases. Currently, this evaluation is often performed manually which is tedious and time consuming and suffers from significant interobserver and intraobserver variability. This paper introduces a new automatic method, based on nonlinear dimensionality reduction (NLDR) for extracting the curve of the LV volume changes over a cardiac cycle from two-dimensional (2-D) echocardiography images. Isometric feature mapping (Isomap) is one of the most popular NLDR algorithms. In this study, a modified version of Isomap algorithm, where image to image distance metric is computed using nonrigid registration, is applied on 2-D echocardiography images of one cycle of heart. Using this approach, the nonlinear information of these images is embedded in a 2-D manifold and each image is characterized by a symbol on the constructed manifold. This new representation visualizes the relationship between these images based on LV volume changes and allows extracting the curve of the LV volume changes automatically. Our method in comparison to the traditional segmentation algorithms does not need any LV myocardial segmentation and tracking, particularly difficult in the echocardiography images. Moreover, a large data set under various diseases for training is not required. The results obtained by our method are quantitatively evaluated to those obtained manually by the highly experienced echocardiographer on ten healthy volunteers and six patients which depict the usefulness of the presented method.  相似文献   
188.
Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers.  相似文献   
189.
Ewing's sarcoma is an aggressive malignancy of bone and soft tissue with high incidence of metastasis and resistance to chemotherapy. Cytochrome P450 (CYP) monooxygenases are a family of enzymes that are involved in the metabolism of exogenous and endogenous compounds, including anti‐cancer drugs, and have been implicated in the aggressive behaviour of various malignancies. Tumour samples and clinical information including age, sex, tumour site, tumour size, clinical stage and survival were collected from 36 adult and paediatric patients with Ewing's sarcoma family tumours. Tissue microarrays slides were processed for immunohistochemical labelling for CYP3A4, CYP3A5 and CYP3A7 using liver sections as positive control. The intensity of staining was scored as negative, low or high expression and was analysed statistically for any association with patients' clinical information. Four cases were later excluded due to inadequate viable tissue. CYP3A4 staining was present in 26 (81%) cases with high expression noted in 13 (40%) of 32 cases. High expression was significantly associated with distant metastases (P < 0.05). CYP3A5 and CYP3A7 were expressed in 5 and 13 cases respectively (15.6%, 40.6%). There was no association between the expression of CYP3A isoforms and age, sex, tumour size, or location (pelvic or extra‐pelvic). None of the biomarkers showed any correlation with overall or disease‐free survival. In conclusion, expression of CYP3A isoforms is noted in Ewing's sarcoma tumours and high CYP3A4 expression may be associated with metastasis. Additional studies are needed to further investigate the role of CYP3A4 in the prognosis of these tumours.  相似文献   
190.
BackgroundThe impact of race and socioeconomic status on clinical outcomes has not been quantified in patients hospitalized with coronavirus disease 2019 (COVID-19).ObjectiveTo evaluate the association between patient sociodemographics and neighborhood disadvantage with frequencies of death, invasive mechanical ventilation (IMV), and intensive care unit (ICU) admission in patients hospitalized with COVID-19.DesignRetrospective cohort study.SettingFour hospitals in an integrated health system serving southeast Michigan.ParticipantsAdult patients admitted to the hospital with a COVID-19 diagnosis confirmed by polymerase chain reaction.Main MeasuresPatient sociodemographics, comorbidities, and clinical outcomes were collected. Neighborhood socioeconomic variables were obtained at the census tract level from the 2018 American Community Survey. Relationships between neighborhood median income and clinical outcomes were evaluated using multivariate logistic regression models, controlling for patient age, sex, race, Charlson Comorbidity Index, obesity, smoking status, and living environment.Key ResultsBlack patients lived in significantly poorer neighborhoods than White patients (median income: $34,758 (24,531–56,095) vs. $63,317 (49,850–85,776), p < 0.001) and were more likely to have Medicaid insurance (19.4% vs. 11.2%, p < 0.001). Patients from neighborhoods with lower median income were significantly more likely to require IMV (lowest quartile: 25.4%, highest quartile: 16.0%, p < 0.001) and ICU admission (35.2%, 19.9%, p < 0.001). After adjusting for age, sex, race, and comorbidities, higher neighborhood income ($10,000 increase) remained a significant negative predictor for IMV (OR: 0.95 (95% CI 0.91, 0.99), p = 0.02) and ICU admission (OR: 0.92 (95% CI 0.89, 0.96), p < 0.001).ConclusionsNeighborhood disadvantage, which is closely associated with race, is a predictor of poor clinical outcomes in COVID-19. Measures of neighborhood disadvantage should be used to inform policies that aim to reduce COVID-19 disparities in the Black community.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-020-06527-1.KEY WORDS: COVID-19, disparities, disadvantage, socioeconomic status, race  相似文献   
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