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【Objective】 To study the yielding rate and distribution of unexpected antibodies in blood transfusion children with thalassemia in Yunnan province, and to explore the blood transfusion strategies. 【Methods】 From January 2016 to December 2021, 298 children with thalassemia, who received blood transfusion treatment in Kunming, Xishuangbanna, Wenshan, Dehong, Yuxi and Baoshan hospitals across Yunnan Province, were selected. The unexpected antibodies of blood plasma were screened by microcolumn gel card. The samples with positive antibodies were identified for alloantibody specificity. 【Results】 Unexpected antibodies were yielded in 67 out of 298(22.48%) transfused children with thalassemia. The positive rates of unexpected antibodies in boys and girls were 16.55%(24/145) and 28.10%(43/153), respectively. The positive rates of unexpected antibodies in Han, Dai, Zhuang, Yi, Bulang, Jinuo and Miao people were 14.06%(18/128), 30.80%(32/104), 35.71%(10/28), 36.36%(8/22), 50.00%(4/8), 60.00%(3/5)and 66.67%(2/3), respectively, with statistically significant differences between each other. The positive rate of unexpected antibodies in ethnic minorities was higher than that in Han. The positive rates of unexpected antibodies in children who received the first transfusion at birth-one year old, 1~3 years old, 3~6 years old and above 6 years old were 12.50%(3/24), 10.14%(7/69), 24.54%(40/163)and 40.48%(17/42), respectively. The positive rates of unexpected antibodies in children with first transfusion after 3 years old were significantly higher than those before 3 years old. The positive rates of unexpected antibodies in children with one transfusion, 1~3, 3~10, 10~20 and more than 20 transfusions were 4.76%(1/21), 12.07%(7/58), 23.71%(23/97), 28.16%(29/103)and 36.84%(7/19), respectively, with statistically significant differences between each other. The number of blood transfusions was positively correlated with the unexpected antibody yielding. The yielding rate of unexpected antibodies in children with α thalassemia, βthalassemia, δ+ βthalassemia and untyped thalassemia was 7.50%(3/40), 17.62%(34/193), 53.70%(29/54)and 9.09%(1/11), respectively(P<0.05). The yielding rate of unexpected antibodies in transfused children with δ+ βthalassemia was the highest. And 57 unexpected antibodies of Rh blood group system were yielded, 6 anti-M antibodies, 2 anti-N antibodies and 2 undetermined. 【Conclusion】 The positive rate of unexpected antibodies in transfused children with thalassemia in Yunnan province is high. Routine antibody screening should be carried out for transfusion children with thalassemia, and blood units, compatible with ABO, Rh and MNS typing results, should be selected to ensure the safety and effectiveness of clinical blood use.
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Objective:To learn about the levels of serum iodine and thyroid function indicators in adults with normal thyroid function in Liaoning Province, to establish the medical reference value range of serum iodine, and to explore the relationship between serum iodine and thyroid function indicators.Methods:From February 2017 to December 2018, one subdistrict and one rural township were selected as the survey sites in the coastal area (Gaizhou City of Yingkou) and inland area (Kangping County of Shenyang) of Liaoning Province, respectively. Permanent residents aged 18 and older who have lived there for 5 years or more were selected as the survey subjects. Blood samples were collected to test the levels of serum iodine and thyroid function indicators [thyroid stimulating hormone (TSH), free triiodothyronine (FT 3), free thyroxine (FT 4), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb)]. The percentile method was used to establish the 95% medical reference value range of serum iodine in adults with normal thyroid function, and Pearson correlation analysis was used to analyze the correlation between serum iodine and thyroid function indicators. Results:A total of 1 621 adults with normal thyroid function were examined, the median serum iodine was 62.0 μg/L, and the 95% medical reference value range was preliminarily determined as 37.0-103.0 μg/L. Among them, the medians serum iodine of males and females (826 and 795 cases) were 62.3 and 61.0 μg/L, respectively, and there was no significant difference between genders ( Z=- 1.26, P = 0.210). The medians serum iodine of adults in coastal and inland areas (827 and 794 cases) were 61.7 and 61.9 μg/L, respectively, and there was no significant difference between areas ( Z = - 0.16, P = 0.870). The medians serum iodine of adults aged 18 - 29, 30 - 39, 40 - 49, 50 - 59 and 60 - 80 (385, 392, 378, 253 and 213 cases) were 61.0, 61.0, 63.0, 65.0 and 62.0 μg/L, respectively, and the difference between ages was statistically significant ( H = 14.52, P = 0.006). Pearson correlation analysis showed that serum iodine was weakly correlated with the level of FT 4 ( r = 0.17, P < 0.001), but not with the levels of TSH, TPOAb and TgAb ( P > 0.05). Conclusions:This study has established the medical reference value range of serum iodine in adults with normal thyroid function in Liaoning Province. Serum iodine is not correlated with the levels of TSH, TPOAb and TgAb.
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Osteoporosis results in decreased bone mass,impaired bone strength and bone microstructure,and thus can easily cause bone fracture.Osteoporosis is one of the common diseases troubling the aging people.Due to the decreased activity of osteoblasts as well as impaired osteogenic differentiation of mesenchymal stem cells,the repair of bone defects accompanied with osteoporosis is very limited.It is a promising way to enhance the healing effect of such bone defect through implanting biomaterials with improved physical and chemical properties as well as elevated bioactivities,since it can mediate the activities of osteogenesis related cells in situ.The author summarizes the popular methods for the modification of biomaterials used for repairing bone defect caused by osteoporotic fractures and provides a prospect in this field,with the aim to provide a reference for the treatment of osteoporotic fractures.
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Objective:To explore the value of low-dose CT in pregnancy with COVID-19.Methods:A retrospective analysis was performed on the clinical characteristics, laboratory tests, and chest CT findings of 12 pregnant women with COVID-19 diagnosed by nucleic acid testing in the Renmin Hospital of Wuhan University from January 20, 2020 to February 16, 2020. Two radiologists blinded to the reconstruction algorithm independently scored subjective image quality on a 5-point Likert scale. Image quality score ≥ 3 was acceptable in clinics. The CT radiation doses were recorded, including CT volume dose index (CTDI vol), dose length product (DLP), and effective radiation dose ( E). Two radiologists observed the distribution, shape, density, and other characteristics of lung lesions, and they also decided whether hilar, mediastinal lymphadenopathy, and pleural changed. Results:A total of 12 pregnant women with COVID-19, 8 had cough, 4 had fever, 2 had chest tightness, and 1 had dyspnea and diarrhea each. The CT image quality score of all patients was 3-4, with an average of 3.46, which fully met the clinical diagnosis requirements. The CTDI vol value was 1.13-4.31 mGy, with an average of 3.02 mGy. The DLP value was 34.48-75.29 mGy·cm, with an average of 55.48 mGy·cm. The Evalue was 0.48-1.05 mSv, with an average of 0.78 mSv. In all cases, chest CT examination showed abnormal manifestations after clinical symptoms, including unilateral lung lesions in 5 cases and bilateral lung lesions in 7 cases, 1 case of ground-glass opacity, 1 case of solidification, 7 cases of ground-glass and consolidation, 1 case of strip opacity, ground-glass, and consolidation and strip cable shadow coexisted in 2 cases. Conclusions:The application of low-dose CT scan in pregnant women with COVID-19 is completely feasible. CT mainly manifested as bilateral lung patchy and flaky ground-glass opacity with consolidation. Active and effective treatment can help recover and improve prognosis.
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Objective:To explore the value of chest low-dose CT (LDCT) in post-discharge follow-up assessments of patients with coronavirus disease 2019 (COVID-19).Methods:The chest CT findings of 58 patients with COVID-19 from March 17 to March 25, 2020 at Remin Hospital of Wuhan University were retrospectively analyzed. Two radiologists independently scored the subjective image quality on a 5-point Likert scale. The signal-to-noise ratio (SNR) and SD air of images and the CT radiation dose parameters were calculated, including the CT volume dose index (CTDI vol), dose length product (DLP), and effective radiation dose ( E). Results:The subjective image quality scores on CT images obtained before and after discharge by readers 1 and 2, were 4.45±0.22, 3.88±0.33 ( P>0.05) and 4.37±0.18, 3.91±0.35 ( P>0.05), respectively. The SNR and SD air in LDCT after discharge were 4.39±0.95 and 7.19±2.41, which were significantly lower than those in routine chest CT before discharge (5.14±1.06, Z=-5.551, P<0.001; 6.48±1.57, Z=-3.217, P<0.001). All of the obtained images were sufficient for diagnosis. The CTDI vol, DLP, and E in LDCT were significantly lower than those in routine CT [(2.41±0.09), (10.53±1.03)mGy, Z=-6.568, P<0.001; (88.03±5.33), (338.74±34.64)mGy·cm, Z=-6.624, P<0.001; and (1.23±0.17), (4.74±0.48)mSv, Z=-5.976, P<0.001]. Conclusions:Patients with COVID-19 can be followed up with low-dose chest CT after discharge.
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Osteoporosis results in decreased bone mass, impaired bone strength and bone microstructure, and thus can easily cause bone fracture. Osteoporosis is one of the common diseases troubling the aging people. Due to the decreased activity of osteoblasts as well as impaired osteogenic differentiation of mesenchymal stem cells, the repair of bone defects accompanied with osteoporosis is very limited. It is a promising way to enhance the healing effect of such bone defect through implanting biomaterials with improved physical and chemical properties as well as elevated bioactivities, since it can mediate the activities of osteogenesis related cells in situ. The author summarizes the popular methods for the modification of biomaterials used for repairing bone defect caused by osteoporotic fractures and provides a prospect in this field, with the aim to provide a reference for the treatment of osteoporotic fractures.
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Nanotechnology offers exciting and innovative therapeutic strategies in the fight against cancer. Nano-scale hydroxyapatite, the inorganic constituent of the hard tissues of humans and animals, is not only an ideal carrier for the delivery of drugs but also exerts selective inhibitory effects on tumor cells. To perform the dual functions, we propose polyglutamic acid-coordinated hydroxyapatite nanoparticles (HA-PGA NP) as both DOX delivery vehicle and sustained calcium flow supplier to achieve a synergistic, tumor-specific therapy in this study. With PGA as the coordinator, the HA-PGA NPs were easily assembled into spherical nano-clusters with low crystallinity. The excellent dispersibility and solubility in the tumor environment endowed the HA-PGA NPs with an improved internalization into the tumor cells, thereby causing a dramatic elevation in the intracellular calcium influx by about 40%, which further induced a cascade of mitochondrial membrane damage, ATP content reduction, and reinforced sensitivity to chemotherapy. After the encapsulation of the model drug DOX, a pH-responsive release profile was achieved via the degradation of the nanoparticles and the deprotonation of PGA in the acidic tumor micro-environment. Consequently, the hybrid system, with the synergistic effects of sustained DOX and calcium overload, exhibited selectively intensified toxicity to tumor cells. The in vivo test further confirmed that the current system exhibited highly selective tumor inhibition and reduced heart toxicity, thus representing an effective anti-tumor platform.
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Portadores de Fármacos/química , Durapatita/química , Nanopartículas/química , Ácido Poliglutámico/química , Animales , Calcio/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Liberación de Fármacos , Sinergismo Farmacológico , Femenino , Humanos , Concentración de Iones de Hidrógeno , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Desnudos , Nanopartículas/toxicidad , Neoplasias/tratamiento farmacológico , SolubilidadRESUMEN
BACKGROUND:Poly(propylene fumarate) (PPF) can crosslink at room temperature, andβ-tricalcium phosphate (β-TCP) has good biocompatibility, but PPF/β-TCP composite bone cement has not yet been systematical y studied. OBJECTIVE:To prepare PPF/β-TCP composite bone cement and to explore its in vitro bioactivity and degradability. METHODS:β-TCP and PPF were respectively synthesized by liquid-phase precipitation and a two-step method, and PPF/β-TCP composite bone cement was prepared through mixing PPF withβ-TCP. The in vitro bioactivity of PPF/β-TCP was compared with the commercial poly(methyl methacrylate) (PMMA) through the ability of forming hydroxyapatite after immersed in simulated body fluid for 7 days. The in vitro degradability of PPF/β-TCP was studied via investigating the transformation of pH values, water uptake and mass loss, compressive strength and morphology at each time point. RESULTS AND CONCLUSION:There were hydroxyapatites formed on the PPF/β-TCP material, but none on the commercial PMMA material. The pH values of the PPF/β-TCP were stable in PBS for 63 days, indicating its degradation is moderate;the mass loss was up to 13.5%after 84 days. Scanning electron microscope displayed the degraded PPF/β-TCP surface, and its compressive strength was decreased gradual y, which good for the integrity and sustainability of mechanical properties during degradation. These results suggest that PPF/β-TCP bone cement holds mineralization and degradability in vitro.
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BACKGROUND:On the basis of thorough debridement, homochronous anterior or staging posterior fixation has been a standard scheme for spinal tuberculosis. Numerous studies confirmed that above approach has obtained good effects, but the anterior approach has some disadvantages, such as complex anatomic structure, great trauma, relatively more complications, and difficult operation and fixator implantation. OBJECTIVE:To observe spinal stabilization and deformity correction in patients with single-segment thoracic/lumbar spinal tuberculosis after posterior debridement and interbody fusion. METHODS:Clinical data of 36 patients with single-segment thoracic/lumbar spinal tuberculosis undergoing one-stage posterior debridement and interbody fusion in the Guangxi Yulin Orthopedics Hospital of Integrated Traditional Chinese and Western Medicine from January 2008 to January 2012 were retrospectively analyzed. There were 2 cases in single T11/12 segment, 4 in T12/L1 segments, 6 in L3/4 segments, 22 in L4/5segments and 2 in L5/S1 segments. Of them, 24 patients suffered from different degrees of spinal nerve injury. At 6, 12 and 24 months after surgery, al patients were folowed up. Bone graft fusion, kyphosis correction, functional recovery of the spinal cord and complications were observed. RESULTS AND CONCLUSION:Al patients were folowed up for 24-38 months. Cobb angle of kyphosis and spinal stenosis rate were significantly improved at 2 years after treatment (P < 0.05). The lumbar back pain symptoms were significantly improved in final folow-up (P < 0.05), with an intervertebral fusion rate of 100%. No lesion residue and recurrence, correction loss, fixation loosening or displacement was found. These results demonstrated that in patients with single-segment thoracic/lumbar spinal tuberculosis, posterior debridement and interbody fusion can effectively reconstruct spinal stabilization, correct deformity, and promote the functional recovery of spinal nerves.
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Objective To investigate the effect of inversion time (TI) on flow-sensitive alternating inversion recovery (FAIR) perfusion imaging of spinal bone marrow (SBM),and evaluate the reproducibility of blood flow (BF) measurements using this technique.Methods Twenty four healthy volunteers without lumbar and other disease with clinical and MR studies were prospectively included.The first 14 healthy volunteers were included to study the effect of TI on ASL perfusion imaging of SBM to get the optimized TI,the remaining 10 volunteers were included to investigate the reproducibility of the SBM arterial spin labeling (ASL) scan protocol.The optimized TI of FAIR spinal bone marrow perfusion experiment was carried out on 14 healthy volunteers on 3.0 T magnet,two adjacent vertebral bodies were orderly selected from each volunteer to measure the △M and the SNR of FAIR perfusion MRI with 5 different TIs (800,1 000,1 200,1 400,1 600 ms),and the vertebral bodies selected order were determined by the order of the subjects enrolled.In addition,FAIR perfusion spinal vertebral BF measurements were repeated in last l0 healthy subjects on L4 or L5 by reposition immediately,paired t test and reproducibility statistics (included within-patient standard deviation (wSD) and within-patient coefficient of variation (WCV)) were used to analyze the test-retest experiment reproducibility.Result TI optimization experiments total included 28 vertebral bodies,when TI (ms) was chose as 800,1 000,1 200,1 400,1 600,ms respectively,the mean △M of spinal bone marrow were 20.8±9.0,29.0± 10.9,36.4± 12.5,26.2± 10.2 and 23.8± 11.5,and the mean SNR were 2.0± 1.0,2.3±0.8,2.4± 1.0,2.3±0.8 and 2.0±0.7.With TI increasing,AM and SNR increased first and then decrcascd,the maximum values of both were achieved when the TI near 1 200 ms.Test-retestexperimcnt were carried on 10 vertebral bodies eventually,and two measurements of spinal vertebral BF perfusion before and after were (108.9±4.6)and (109.2 ±4.6)ml · 100g-1· min 1,respectively,and no significant difference was found (t=-0.157,P=0.879),wCV of the measurements was 3.28% (3.57/109.06).Conclusion The optimal TI was 1 200 ms for spinal bone marrow ASL perfusion image,at which the maximum AM,higher SNR,and good reproducibility for the FAIR spinal bone marrow perfusion imaging can be achieved.
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Objective To explore brain activity features during the resting state in alcohol dependent individuals,and study the relationship between the brain activity features and alcohol dependent individuals' clinical symptoms.Methods Twenty-four alcohol dependent individuals and 22 healthy control subjects,well matched in gender,age,education and handedness,were enrolled as the alcohol dependent group and control group respectively.AGE 3.0 T MR scanner was used to acquire all the subjects' resting state data. DPARSF software was used to process resting functional MRI data,and then the whole brain fractional amplitudes of low frequency fluctuation (fALFF) data were acquired.Two-sample t test statistical analysis was made to access fALFF difference between the two groups. Results In comparison with the control group,the alcohol dependent group showed reduced fALFF in bilateral medial prefrontal gyrus,right inferior occipital gyrus,left precuneus,left inferior temporal gyrus,and left posterior lobe of cerebellum (0.64-1.69 vs.0.87-1.78,t =- 4.23- - 2.79,P < 0.05 ). fALFF was increased in the alcohol dependent group at the anterior cingulate,bilateral inferior frontal gyrus,right middle frontal gyrus,bilateral insular lobe,bilateral dorsal thalamus ( 0.86-1.82 vs. 0.76-1.58,t =3.56-3.96,P < 0.05 ).Conclusion Alcohol dependent individuals had abnormal activity at the bilateral prefrontal lobe,anterior cingulate,bilateral dorsal thalamus,bilateral insular lobe,left posterior lobe of cerebellum et al,during the resting state,and these abnormal activities might be related with clinical manifestation and pathophysiology.
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Objective To explore the feasibility to diagnose ureterolithiasis by 16-multidetector spiral computed tomography (16-MDCT) at different low doses based on body mass index (BMI).Methods A total of one hundred patients from 2009 Sep to 2010 Feb suspected of ureterolithiasis were randomly divided into 2 equal groups undergoing 16-MDCT at standard-dose (120 kV, 240 mA) or lowdose (120, 80, and 50 mA, respectively) based on the body mass index (BMI).Taking the clinical diagnosis as the standard, the sensitivity level, specificity level, and positive predictive value of these groups were compared.Results The dose length product ( DLP ) of the low-dose CT group and the average CT dose index (CTDIvol ) were 18.95 and 6.65 mGy, respectively.There was significant difference between the two groups ( t = 31.78, P < 0.01 ).The sensitivity level, specificity level, and positive predictive value of the low-dose group were 97.1% , 94.0% , and 94.3% , respectively, all not significantly different from those of the standard-dose groups (97.3% , 96.0% , and 97.3% , respectively,P >0.05).Conclusions It is feasible to diagnose ureterolithiasis by low-dose 16-MDCT based on BMI with the obtained image quality meeting the clinical diagnostic requirements.
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Objective To observe the changes of the bilateral hippocampal volume (BHV) and 1H-MRS appearance of chronic alcohol dependent (CAD) patients and to provide quantitative information for the clinical diagnosis of CAD. Methods The conventional MR imaging including three-dimensional fast spoiled gradient recalled echo (3D-FSPGR) and 1H-MRS were performed on 16 patients with CAD (CAD group)and 18 cases of volunteer ( control group). The BHV were measured in both groups and the standardized BHV in CAD group and control group were compared. 1H-MRS metabolites including N-acetylaspartate (NAA), Choline compounds (Cho), Creatine (Cr), and myoinositol (mI) of the bilateral cephalic hippocampus were acquired. The ratios of Cho/Cr, Cho/NAA, NAA/Cr and mI/Cr within the bilateral cephalic hippocampus of the two groups were compared. The t test was used to compare the BHV and the ratios of 1H-MRS in the bilateral cephalic hippocampus between the two groups. Results In CAD group,the left and the right hippocampal volume were 1. 881 ±0. 292, 2. 139 ±0. 328 respectively while they were 2. 106 ±0. 245 and 2. 267 ±0. 271 respectively in the control group. The BHV had no significant difference between the left and the right in either the CAD group or the control group (t =0. 232, 0. 147 respectively,P > 0. 05). The BHV had no significant difference between the CAD group and control group(t = 0. 424,0. 131 respectively ,P >0. 05 ). The Cho/Cr and NAA/Cr in the right cephalic hippocampus of the CAD group were 1. 225 ±0. 210 and 1. 145 ±0. 034 respectively, while they were 1. 429 ±0. 286, 1. 612 ±0. 444 respectively in the control group(t =0. 321,0. 408 ,P <0. 05 ). The Cho/NAA, mI/Cr in the right cephalic hippocampus and the Cho/Cr, Cho/NAA, NAA/Cr and mI/Cr in the left cephalic hippocampus between the two groups had no statistically significant difference. Conclusion 1H-MRS could potentially provide early diagnostic evidence for CAD patients before the onset of cerebral morphological changes.
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Objective To assess the effectiveness of Z-axis automatic tube current modulation ( ATCM) technique with respect to dose reduction and image noise in the thyroid regional tissues during neck computed tomography angiography (CTA). Methods A total of 140 patients underwent neck CTA with 64-slice spiral CT, and were randomized into fixed-tube current group and ATCM group. Objective noise, CTDIw, DLP and mA of each group were recorded. Results The image qualities of all the patients were diagnostically acceptable, though the objective noise of neck in the ATCM group was higher than that in the group of fixed-tube current (P< 0.05 ). The radiation doses in the ATCM group [ CTDIw (35.99±1.31 ) mGy, DLP (11 121.39 ±5.51) mGy·cm] were significantly inferior to those in the group of fixed tube current [ CTDIw (43.22±1.42) mGy, DLP (1514.45±5.56) mGy·cm]. Conclusions Compared with fixedtube current technique, ATCM technique could significantly reduce the radiation dose in neck CT with diagnostic acceptability of the image quality.
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On the basis of previous researches, we have prepared Bovine hemoglobin-loaded nanoparticles (HbP), using the double emulsion method. More mild dispersing treatment was employed during the primary and secondary emulsion; over 97% encapsulation efficiency (EE%) and an average size about 286 nm were achieved by using surfactants, screening solvents, as well as avoiding the traditional strong dispersing process. The value of Hydrophile-lipophile balance in oil phase exerted a significant effect on EE% and led to higher EE% when matched with the surfactants in outer aqueous phase. When compared with the sole solvent Span80, the mixed surfactants such as Poloxemer188/Span80 stabilized the emulsion more efficiently and increased the EE%. The higher concentration of surfactants resulted in higher EE% and narrower size distribution. But over some amount, the surfactants had no significant effect on EE%, resulting in larger size and polydispersity index (PDI). The appropriate removal rate of solvents contributes to higher EE%, smaller size and PDI.
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Animales , Bovinos , Humanos , Materiales Biocompatibles , Sustitutos Sanguíneos , Química , Emulsiones , Hemoglobinas , Química , Nanopartículas , Tamaño de la Partícula , Solventes , Química , Tensoactivos , QuímicaRESUMEN
Hemoglobin-loaded nano-sized particles with oxygen carrying capacity were prepared. All experiments were performed using biodegradable polymer poly (polyepsilon-caprolactone) (PCL) as matrix polymer. Optimized preparation parameters led to nanoparticles with well-defined characteristics such as size <200 nm, P50 27 mmHg and high encapsulation efficiency up to 99.4%. The results of in vitro and vivo studies suggested that Hb-loaded particles did not activate complements. After the nanoparticles suspension was injected into the mice via tail vein, the particles did not cause significant changes in total platelet counts. Apparently, the hemoglobin-loaded nanoparticles can serve as a potential candidate in substitution for red cells.
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Animales , Bovinos , Ratones , Materiales Biocompatibles , Química , Sustitutos Sanguíneos , Química , Hemoglobinas , Química , Ensayo de Materiales , Nanopartículas , Química , Tamaño de la Partícula , Poliésteres , QuímicaRESUMEN
The progress of researches on drug-loaded nanoparticles was summarized in this review. The major emphasis was laid on the selection of wall polymers, technology of preparation, surface modification, investigation of release in vitro and biocompatibility evaluation. Additionally, we envisioned a perspective regarding the development in this field. With the development of synthesis of biodegradable polymer, with the appearance of novel equipment, and with the deep-going studies on modification of nanoparticles surface method, on fabrication of nanoparticles art as well as on evaluation of drug release and reaction between drug and organ, further researches in this field will open up the way to applications of drug-loaded nanoparticles in larger field.
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Cápsulas , Preparaciones de Acción Retardada , Portadores de Fármacos , Química , Farmacocinética , Composición de Medicamentos , Nanomedicina , Nanopartículas , Química , Poliésteres , QuímicaRESUMEN
Liposomal Brucine (LB) with high encapsulation efficiency (72%) and small particle diameter (mean particle diameter, 54 nm) was prepared by ethanol-dripping method. The safety and pharmacodynamic action of LB, a new transdermal preparation, were investigated in details with the use of white rabbits, guinea-pigs and mice, respectively. The tests revealed that LB had no acute toxicity to integral and broken skin, and had no allergic effects on skin. In writhing test, the analgesic effect of LB was higher than that of free brucine. The anti-inflammatory activity of LB was significantly higher than that of free brucine (P<0.01). Meanwhile, LB exhibited a better dose-response manner and a longer duration of analgesic effects. In conclusion, LB could reduce the toxicity of brucine, enhance the analgesic and antiinflammatory effects of brucine, and achieve its sustained-release.
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Animales , Femenino , Masculino , Ratones , Conejos , Administración Cutánea , Analgésicos , Farmacología , Antiinflamatorios , Farmacología , Cobayas , Liposomas , Química , Piel , Estricnina , Farmacología , Toxicidad , Pruebas de Toxicidad AgudaRESUMEN
Bovine Hb-loaded nanoparticles with modulated size of pores, for use as blood substitutes, were prepared and a nonenzymatic reduction system including two-step-reduction and process optimization was established to control the metHb level in the present study. After the first-step-reduction procedure was performed, the raw BHb, being oxidized severely, was encapsulated to form nanoparticles by the modified double emulsion method. The binary solvent of dichloromethane (DCM) and acetonitrile (Aci) showed properties such as minimizing Hb oxidation and enlarging the pores of nanopartilces. Based on the size of pores o f nanoparticles evaluated by the diffusion of various substances wi thdifferent molecular weights, reducing agents such as ascorbic acid and glutathione present in the plasma were selected to perform the second-step-reduction, i. e. to further reduce the metHb in nanoparticles. The metHb level was reduced from over 90% in the raw materials to 1.25% by the two-step-reduction and controlled preparation; this is near the level of native blood, possessing the ability of carrying/releasing oxygen.
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Animales , Bovinos , Humanos , Materiales Biocompatibles , Química , Sustitutos Sanguíneos , Química , Hemoglobinas , Química , Metabolismo , Metahemoglobina , Química , Nanopartículas , Química , PorosidadRESUMEN
Rapid re-endothelialization of implanted coronary artery stent is a new way for preventing restenosis. In this paper, adhesive polypeptide mimics of marine organism and antibodies potentially selective targeting with CD34 antigens on endothelial cells (ECs) were immobilized onto ethylene-vinyl acetate copolymer (EVA) coatings for improving the re-endothelialization process. The results showed that the attachments, growths, viabilities, as well as cell retentions of ECs on EVA were improved after modification. The immobilized polypeptide promoted the attachments of ECs, but overmuch polypeptide would restrict the attachments. With the increase of antibody concentration, the immobilized antibodies and cell attachments were improved.