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81.
A. Touré D. Cissé KJJO. Kadio A. Camara FA. Traoré A. Delamou S. Sididé C. Kouyaté IS. Bangoura MM. Diallo TM. Tounkara F. Traoré MS. Sow N. Khanafer M. Cissé 《Revue d'épidémiologie et de santé publique》2018,66(4):273-279
Background
Late or inadequate therapeutic management increases the risk of mortality associated with HIV/AIDS. The aim of this study was to analyze the proportion and factors associated with loss of follow-up in HIV patients who receiving antiretroviral therapy at Conakry.Methods
A retrospective cohort study was conducted in HIV patients aged over 15 years and who receiving antiretroviral therapy. Between August 1, 2008 and July 31, 2015, all patients managed by the ambulatory treatment center of the Guinean Women Association against AIDS and sexually and transmissible infection were included. Loss of follow-up was defined as no follow-up visit within 3 months. Kaplan–Meier curves and multivariate Cox regression modelResults
614 patients aged 36.3 ± 11.2 years, mainly females (68.4%) and living in Conakry (80.5%) were included. Among them, 104 were loss to follow-up, corresponding to a proportion rate of 16.9% (95% CI: 14.2–19.7%) or 5.79/100 person-years. The results of multivariate analyses showed that factors independently associated with loss of follow-up were malnutrition (AHR = 7.05; 95% CI: 2.05–24.27; P = 0.002) and CD4 cells account at the initiation of AHR (2.35; 95% CI: 1.61–6.39; P = 0.016) in patients with 201–350 CD4/μL and 5.83 (95% CI: 2.85–11.90; P < 0.001) in patients with less than 150 CD4/μL.Conclusion
Despite efforts of health care workers and free antiretroviral therapy, many patients were loss to follow-up. Multivariate analysis showed that malnutrition and low CD4 account were independently associated with loss to follow-up. 相似文献82.
Choe Sooyeon Yoon Chang Ho Kim Mee Kum Hyon Joon Young Yu Young Suk Oh Joo Youn 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(2):359-366
Graefe's Archive for Clinical and Experimental Ophthalmology - To determine the incidence of spontaneous regression of congenital corneal opacity (CCO) and identify clinical factors associated... 相似文献
83.
Won Sik Jang Ki Hong Kim Kyoung Taek Lim Jongsoo Lee Ji Eun Heo Hyojeong Kwon Hyoeun Kang Jae Ho Lee Seung-Ah Choe Dae Keun Kim 《Andrologia》2020,52(11):e13809
Total motile sperm count is an important parameter for predicting the probability of natural pregnancy. We have externally validated the Samplaski's post-varicocele repair semen analysis nomogram to confirm the predictive accuracy of total motile sperm count. A total of 300 patients who had undergone varicocelectomy between July 2016 and July 2019 from 4 treatment centres were included in this validation cohort study. The predictive performance of the externally validated nomogram was revealed by applying the Pearson correlation coefficient (R = 0.328; 95% confidence interval (CI) 0.220–0.435; p < .001). Compared to Samplaski's nomogram result (R = 0.581; 95% CI 0.186–0.729), our study also revealed a statistically significant rate. However, it had a relatively lower correlation coefficient rate. Notably, the predicted total motile sperm count was lower than the observed post-varicocelectomy total motile sperm count. The calibration plot revealed that the discrepancy between the predicted and observed total motile sperm count was plausible. However, it had low explanatory power in this nomogram model. This validation study demonstrates that the post-varicocele repair Samplaski's nomogram predicts a relatively lower total motile sperm count than the observed count. 相似文献
84.
An Activin A/BMP2 Chimera,AB204, Displays Bone‐Healing Properties Superior to Those of BMP2
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Byung‐Hak Yoon Luis Esquivies Chihoon Ahn Peter C Gray Sang‐kyu Ye Witek Kwiatkowski Senyon Choe 《Journal of bone and mineral research》2014,29(9):1950-1959
Recombinant bone morphogenetic protein 2 (rhBMP2) has been used clinically to treat bone fractures in human patients. However, the high doses of rhBMP2 required for a therapeutic response can cause undesirable side effects. Here, we demonstrate that a novel Activin A/BMP2 (AB2) chimera, AB204, promotes osteogenesis and bone healing much more potently and effectively than rhBMP2. Remarkably, 1 month of AB204 treatment completely heals tibial and calvarial defects of critical size in mice at a concentration 10‐fold lower than a dose of rhBMP2 that only partially heals the defect. We determine the structure of AB204 to 2.3 Å that reveals a distinct BMP2‐like fold in which the Activin A sequence segments confer insensitivity to the BMP2 antagonist Noggin and an affinity for the Activin/BMP type II receptor ActRII that is 100‐fold greater than that of BMP2. The structure also led to our identification of a single Activin A‐derived amino acid residue, which, when mutated to the corresponding BMP2 residue, resulted in a significant increase in the affinity of AB204 for its type I receptor BMPRIa and a further enhancement in AB204's osteogenic potency. Together, these findings demonstrate that rationally designed AB2 chimeras can provide BMP2 substitutes with enhanced potency for treating non‐union bone fractures. © 2014 American Society for Bone and Mineral Research. 相似文献
85.
Sara Kim Seoyun Choe Junseong Kim Sanga Nam Yeon Shin Sunmi Lee 《Osong Public Health and Research Perspectives》2014,5(1):40-45
Objectives
According to the Korea Centers for Disease Control and Prevention, new active tuberculosis (TB) cases have increased since 2001. Some key factors explain and characterize the transmission dynamics of Korean TB infection, such as a higher ratio of latent individuals and a new reporting system implemented in 2001, among others.Methods
We propose a mathematical TB model that includes exogenous reinfection to gain a better understanding of the recent trend for TB incidence. We divide the simulation time window into two periods, 1970–2000 and 2001–2012, according to the implementation date of a new TB detection system.Results
Two sets of parameters, including the transmission rate, the latent period, the recovery rate, and the proportion of exogenous reinfection, are estimated using the least-squares method and calibrated to data on the incidence of active TB.Conclusion
Among some key parameters in the model, the case finding effort turned out to be the most significant impacting component on the reduction in the active TB cases. 相似文献86.
Structure of the kainate receptor subunit GluR6 agonist-binding domain complexed with domoic acid 总被引:4,自引:0,他引:4
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Nanao MH Green T Stern-Bach Y Heinemann SF Choe S 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(5):1708-1713
We report the crystal structure of the glycosylated ligand-binding (S1S2) domain of the kainate receptor subunit GluR6, in complex with the agonist domoate. The structure shows the expected overall homology with AMPA and NMDA receptor subunit structures but reveals an unexpected binding mode for the side chain of domoate, in which contact is made to the larger lobe only (lobe I). In common with the AMPA receptor subunit GluR2, the GluR6 S1S2 domain associates as a dimer, with many of the interdimer contacts being conserved. Subtle differences in these contacts provide a structural explanation for why GluR2 L483Y and GluR3 L507Y are nondesensitizing, but GluR6, which has a tyrosine at that site, is not. The structure incorporates native glycosylation, which has not previously been described for ionotropic glutamate receptors. The position of the sugars near the subunit interface rules out their direct involvement in subunit association but leaves open the possibility of indirect modulation. Finally, we observed several tetrameric assemblies that satisfy topological constraints with respect to connection to the receptor pore, and which are therefore candidates for the native quaternary structure. 相似文献
87.
We compared the ability of recombinant human tumor necrosis factor- alpha (rHuTNF-alpha) and tumor necrosis factor-beta (rHuTNF-beta) to stimulate polymorphonuclear neutrophil (PMN) migration and superoxide production. Significant PMN migration occurred across polycarbonate filters after stimulation with rHuTNF-alpha at concentrations ranging from 10(-7) to 10(-10) mol/L and at 10(-7) to 10(-8) mol/L for rHuTNF- beta and N-formylmethionyl-leucyl phenylalanine (FMLP), whereas recombinant human interferon-gamma was only minimally active at 10(-7) mol/L and recombinant human interleukin-1 alpha was inactive at the doses tested. In addition, antibodies to rHuTNF-alpha completely inhibited rHuTNF-alpha but not rHuTNF-beta or FMLP-induced PMN migration. Combinations of rHuTNF-alpha and rHuTNF-beta (at similar molar concentrations) stimulated PMN migration levels comparable to that obtained with rHuTNF-alpha alone. Checkerboard analyses performed by placing different concentrations of rHuTNF-alpha and rHuTNF-beta above and below polycarbonate filters of microchemotaxis chambers demonstrated that rHuTNF-alpha and rHuTNF-beta stimulated both chemotactic and chemokinetic responses by PMN. Additional studies demonstrated that 1 X 10(-8) mol/L rHuTNF-alpha and 3 X 10(-9) mol/L rHuTNF-beta (which represents 10(4) U/mL of each cytokine) were similar in their ability to induce superoxide production by PMNs; however, at ten- to 100-fold lower molar concentrations (10(3) and 10(2) units), rHuTNF-alpha was significantly more active than rHuTNF-beta. At the doses tested, both cytokines were less active than phorbol myristate acetate at stimulating O2- release. The results demonstrate that rHuTNF- alpha and rHuTNF-beta differ quantitatively but not qualitatively in their effects on PMN functions in vitro and suggest that rHuTNF-beta may be less toxic than rHuTNF-alpha in vivo. 相似文献
88.
Choe R Durduran T Yu G Nijland MJ Chance B Yodh AG Ramanujam N 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(22):12950-12954
The feasibility of transabdominal near-infrared (NIR) spectroscopy for detecting and quantifying fetal hypoxia in utero is demonstrated in a pregnant ewe model. A frequency domain NIR spectroscopy probe, consisting of two detectors and six sources operating at three wavelengths (675, 786, and 830 nm), was placed on the maternal abdomen directly above the fetal head. Fetal hypoxia was indirectly induced through occlusion of uterine blood flow for approximately 3 min. NIR photon diffusion measurements were made during a baseline period, during hypoxia of the fetus, and during recovery. Fetal blood samples were drawn from the fetal brachial artery and jugular veins at several time points during the cycle. Seven hypoxic cycles were induced in a total of five pregnant ewes. The NIR measurements were analyzed by using a two-layer diffusion model to deconvolve the fetal blood saturation from that of the pregnant ewe. Fetal hypoxia was detected. Good agreement was found between fetal blood saturation determined by the transabdominal NIR method and arterial and venous fetal blood saturation quantified from fetal blood samples by using a hemoximeter. 相似文献
89.
Potent neutralization of severe acute respiratory syndrome (SARS) coronavirus by a human mAb to S1 protein that blocks receptor association 总被引:46,自引:0,他引:46
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Sui J Li W Murakami A Tamin A Matthews LJ Wong SK Moore MJ Tallarico AS Olurinde M Choe H Anderson LJ Bellini WJ Farzan M Marasco WA 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(8):2536-2541
Effective prophylaxis and antiviral therapies are urgently needed in the event of reemergence of the highly contagious and often fatal severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) infection. We have identified eight recombinant human single-chain variable region fragments (scFvs) against the S1 domain of spike (S) protein of the SARS-CoV from two nonimmune human antibody libraries. One scFv 80R efficiently neutralized SARS-CoV and inhibited syncytia formation between cells expressing the S protein and those expressing the SARS-CoV receptor angiotensin-converting enzyme 2 (ACE2). Mapping of the 80R epitope showed it is located within the N-terminal 261-672 amino acids of S protein and is not glycosylation-dependent. 80R scFv competed with soluble ACE2 for association with the S1 domain and bound S1 with high affinity (equilibrium dissociation constant, Kd=32.3 nM). A human IgG1 form of 80R bound S1 with a 20-fold higher affinity of 1.59 nM comparable to that of ACE2 (Kd=1.70 nM), and neutralized virus 20-fold more efficiently than the 80R scFv. These data suggest that the 80R human monoclonal antibody may be a useful viral entry inhibitor for the emergency prophylaxis and treatment of SARS, and that the ACE2-binding site of S1 could be an attractive target for subunit vaccine and drug development. 相似文献
90.
Jung Yeon Heo Ji Eun Lee Hye Kang Kim Kang-Won Choe 《Emerging infectious diseases》2014,20(5):875-877
During April 2011–March 2012, we retrospectively reviewed medical records for South Korea soldiers to assess the etiology and epidemiology of acute viral lower respiratory tract infections. Adenovirus was the most commonly identified virus (63.2%) and the most common cause of pneumonia (79.3%) and hospitalization (76.6%); 3 soldiers died of adenovirus-related illness. 相似文献