Functional exercise on patients after sports meniscus injury / Exercício funcional em pacientes após lesão esportiva de menisco / Ejercicio funcional en pacientes tras lesión deportiva de menisco

ABSTRACT Introduction Knee meniscus injury is a common sports injury, and minimally invasive surgery under knee arthroscopy has become an ideal method to treat meniscus injuries. This surgery rehabilitation has been improved, and several studies on the effects of functional exercise in the range of treatment are still inconclusive. Objective Study the functional exercise rehabilitation effects in patients after sports meniscus injury. Methods Twenty patients with meniscus-medial injury being operated on were selected, including eight men and 12 women. They were randomly divided into neuromuscular and strength training groups (11). Signs and symptoms were assessed before and eight weeks after treatment. JOA score indices and gait tests were compared. The impact of rehabilitation differences was evaluated in each group. Results Eight weeks after rehabilitation in both groups, the scores of the strength training group were higher than the neuromuscular group; the difference between the groups was statistically significant (P<0.05). Conclusion Functional exercise accelerates joint recovery, reflected in increased strength of adjacent muscles. The muscle and joint training effects on postoperative meniscus injury are worthy of recognition. The baropodometry revealed distinctions in walking patterns between different rehabilitation methods. From the perspective of this research, rehabilitation methods combined with proprioceptive exercises are complementary. Evidence Level II; Therapeutic Studies - Investigating the result.

RESUMO Introdução Lesão no menisco do joelho é uma lesão esportiva comum e a cirurgia minimamente invasiva sob artroscopia no joelho tornou-se um método ideal para tratar lesões no menisco. A reabilitação dessa cirurgia vem sendo aprimorada e vários estudos sobre os efeitos do exercício funcional no leque de tratamento ainda são inconclusivos. Objetivo Estudar os efeitos da reabilitação com exercício funcional em pacientes após a lesão esportiva do menisco. Métodos Foram selecionados 20 pacientes com lesão menisco-medial a serem operados, incluindo 8 homens e 12 mulheres. Divididos aleatoriamente em 2 grupos: grupo de treinamento neuromuscular e grupo de treinamento força (11). Sinais e sintomas foram avaliados antes do tratamento e 8 semanas após o tratamento, índices de score JOA e teste de marcha foram comparados, as diferenças do impacto da reabilitação em cada grupo foram avaliadas. Resultados Oito semanas após a reabilitação dos dois grupos, os escores do grupo de treinamento de força foram superiores aos do grupo neuromuscular, a diferença entre os grupos foi estatisticamente significante (P<0,05). Conclusão O exercício funcional acelera a recuperação das articulações, refletida no aumento da força dos músculos adjacentes. O efeito do treinamento muscular e articular na lesão do menisco pós-operatório é digno de reconhecimento. A baropodometria revelou distinções no padrão de marcha entre os diferentes métodos de reabilitação. Na perspectiva desta pesquisa, métodos de reabilitação combinados com exercícios proprioceptivos são complementares. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.

RESUMEN Introducción La lesión de menisco de la rodilla es una lesión deportiva común y la cirugía mínimamente invasiva por artroscopia de rodilla se ha convertido en un método ideal para tratar las lesiones de menisco. La rehabilitación de esta cirugía ha sido mejorada y varios estudios sobre los efectos del ejercicio funcional en el rango de tratamiento aún no son concluyentes. Objetivo Estudiar los efectos de la rehabilitación con ejercicio funcional en pacientes tras una lesión de menisco deportiva. Métodos Se seleccionaron 20 pacientes con lesión de menisco-medial para ser operados, incluyendo 8 hombres y 12 mujeres. Se dividieron aleatoriamente en 2 grupos: grupo de entrenamiento neuromuscular y grupo de entrenamiento de fuerza (11). Se evaluaron los signos y síntomas antes del tratamiento y 8 semanas después del mismo, se compararon los índices de puntuación JOA y la prueba de marcha, y se evaluaron las diferencias del impacto de la rehabilitación en cada grupo. Resultados Ocho semanas después de la rehabilitación para ambos grupos, las puntuaciones del grupo de entrenamiento de fuerza fueron mayores que las del grupo neuromuscular, la diferencia entre los grupos fue estadísticamente significativa (P<0,05). Conclusión El ejercicio funcional acelera la recuperación de la articulación, lo que se refleja en el aumento de la fuerza de los músculos adyacentes. El efecto del entrenamiento muscular y articular en la lesión postoperatoria del menisco es digno de reconocimiento. La baropodometría reveló diferencias en el patrón de la marcha entre los diferentes métodos de rehabilitación. Desde la perspectiva de esta investigación, los métodos de rehabilitación combinados con los ejercicios propioceptivos son complementarios. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.

Experience of 2003 SARS has a negative psychological impact on healthcare workers in the COVID-19 pandemic: a cross-sectional study

ABSTRACT BACKGROUND: The COVID-19 pandemic has instilled fear and stress among healthcare workers. OBJECTIVES: The aim of this study was to assess work stress and associated factors among healthcare workers during the COVID-19 outbreak and to evaluate whether prior experience of treating severe acute respiratory syndrome (SARS) had a positive or negative influence on healthcare workers' stress levels during the COVID-19 pandemic. DESIGN AND SETTING: Cross-sectional survey in a tertiary hospital in Kaohsiung City, in southern Taiwan. METHODS: The survey was conducted using an online self-administered questionnaire to measure the stress levels among healthcare workers from March 20 to April 20, 2020. The stress scales were divided into four subscales: worry of social isolation; discomfort caused by the protective equipment; difficulties and anxiety regarding infection control; and workload of caring for patients. RESULTS: The total stress scores were significantly higher among healthcare workers who were aged 41 or above, female, married, parents and nurses. Those with experience of treating SARS reported having significantly higher stress scores on the subscale measuring the discomfort caused by protective equipment and the workload of caring for patients. During the COVID-19 outbreak, frontline healthcare workers with experience of treating SARS indicated having higher stress levels regarding the workload of caring for patients than did non-frontline healthcare workers with no experience of treating SARS. CONCLUSIONS: Work experience from dealing with the 2003 SARS virus may have had a negative psychological impact on healthcare workers amidst the COVID-19 outbreak.

Is Ki-67, keratin 16, involucrin, and filaggrin immunostaining sufficient to diagnose inflammatory linear verrucous epidermal nevus? A report of eight cases and a comparison with psoriasis vulgaris

Abstract: Inflammatory linear verrucous epidermal nevus and linear psoriasis are sometimes hard to differentiate clinically and pathologically. Although immunohistochemical expression of keratin 10 (K10), K16, Ki-67, and involucrin may be useful for differentiating both entities, these results have been reported in only a few cases. We collected data from 8 patients with inflammatory linear verrucous epidermal nevus, 11 with psoriasis vulgaris, and 8 healthy controls and evaluated immunohistochemical expression of Ki-67, K16, involucrin, and filaggrin among them. Ki-67 and K16 overexpression was similar in inflammatory linear verrucous epidermal nevus and psoriasis vulgaris compared with normal skin. Although staining for involucrin showed discontinuous expression in parakeratotic regions in 4 inflammatory linear verrucous epidermal nevus cases, it was continuous in the other 4 cases and in all psoriasis vulgaris cases. Filaggrin expression was present in hyperkeratotic regions but scarce in parakeratotic areas in both inflammatory linear verrucous epidermal nevus and psoriasis vulgaris. The immunostaining pattern of Ki-67, K16, involucrin, and filaggrin may be insufficient to discriminate inflammatory linear verrucous epidermal nevus from psoriasis vulgaris.

Clinical effects of intravitreal perfluoropropane tamponade and laser photocoagulation for the treatment of highly myopic foveoschisis / 眼科新进展

Objective To observe and analyze the clinical outcomes of perfluoropropane (C3 Fs) injection and laser photocoagulation on myopic foveoschisis.Methods A total of 14 patients (18 eyes) diagnosed as myopic foveoschisis were enrolled in this retrospective study.All patients received intraocular tamponade of 0.5-0.7 mL C3 F8,and after 1 week,underwent macular photocoagulation.These patients were given the best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) examination for central foveal thickness (CFT) and maximal macular thickness (MMT) before and after treatment.Results OCT examination showed that the mean CFT decreased significantly from (494.00 ±454.80) iμm before treatment to (193.61 ± 97.42) μm at the last follow-up,with statistical significance (P =0.01),and the mean MMT decreased from (687.33 ± 385.15)pμn to (331.06 ± 109.31)μm at the same duration,approaching significant difference (P =0.001).The foveoschisis healed completely and partially in 14 eyes at the last follow-up,the mean CFT decreased significantly from (567.36 ±493.01) μm before treatment to (171.43 ± 90.84) μm after treatment,with statistical significance (P =0.006),and the mean MMT decreased from (744.14 ± 417.38)μm to (303.86 ± 8.62)prn at the same duration,approaching significant difference (P =0.002).Patients' BCVA before treatment was (0.94 ± 0.39) logMAR,of which 13 eyes had BCVA ＜ 0.6 logMAR,and increased to (0.92 ± 0.36) logMAR at the last follow-up,with no significant difference (P =0.78).The foveoschisis healed completely and partially in 14 eyes,and the BCVA was (1.04 ± 0.37) logMAR before treatment,up to (0.90 ± 0.34) logMAR after treatment,and the difference was not statistically significant (P =0.16).At the last follow-up,the vision of 4 eyes was increased by 2 lines and above,and unchanged in 10 eyes.All patients had no visual symptoms such as dark spots and no increase in intraocular pressure after treatment.Conclusion Intraocular C3 F8 tamponade and macular photocoagulation can be an satisfying alternative treatment for patients with myopic foveoschisis.

Construction of Lentivirus Vector Carrying HGF and Exploration of Transfection Condition of Rat Adipocyte-derived Mesenchymal Stem Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was to construct the lentivirus vector carrying hepatocyte growth factor (HGF) gene and to explore the condition for transfecting the adipocyte-derived mesenchymal stem cells (ADSC) by HGF lentivirus.</p><p><b>METHODS</b>The target gene was obtained from plasmid carrying HGF gene by PCR and was cloned into GV287 vector. The recombinant GV287-HGF vector plasmid and lentivirus-packing plasmid were co-transfected into 293 T cells to generate HGF lentivirus, and the virus titer was assayed, then the ADSC were transfected by using recombinant HGF lentivirus, and the optimal multplicity of infection (MOI) was detected.</p><p><b>RESULTS</b>The PCR product of HGF gene was consistent with expectant sizes, suggesting that the electrophoretic result of recombinant GV287-HGF plasmid PCR product was correct. The sequencing analysis of cleaved product showed consistance of obtained results with the sequences of target gene, suggesting correct construction of recombinant lentivirus carrying HGF gene. The ELISA showed that the virus tilter was 5×10(8) TU/ml. The optimal MOI for transfecting ADSC with recombinant lentivirus carrying HGF gene was 50.</p><p><b>CONCLUSION</b>The lentivirus vector expressing human HGF gene has been constructed, and transfected the ADSC succesfully. This study lays a foundation for further stadying the ADSC over-expressioning HGF, treating the radiation damage of bone marrow and impartant internal organs.</p>

Detection on effect of different processed Cibotium barometz on osteoblasts by CCK-8 / 中国中药杂志

The pancreatic enzyme-II type collagenase digestion method was adopted for primary culture of osteoblasts, inoculation and passage. They were identified by alkaline phosphatase dye-liquor. N-butanol extract fractions from different processed products of Cibotium barometz were prepared. The above osteoblasts were jointly cultured with protocatechuic acid, protocatechuic aldehyde, kojic acid and the mixed control liquid of the above three substances, and their proliferation was detected by CCK-8. Various n-butanol extract fractions from different processed products of C. barometz showed a significant proliferative effect on osteoblasts in the order of the wined > the heated > the salted > the sand-heated and wined system > the alcohol-processed > the steamed > the crude. The q test showed no significant difference among sand-heated, alcohol-processed and steamed C. barometz, no significant difference between heated and salted C. barometz. Various control substances also showed a certain proliferative effect on osteoblasts in the order of the mixed control > protocatechuic aldehyde > protocatechuic acid > kojic acid. The q test showed no significant difference between protocatechuic aldehyde and protocatechuic acid. All of n-butanol extract fractions from different processed products of C. barometz showed a significant effect on osteoblast proliferation, of which wined C. barometz showed the best effect. All of phenolic compounds such as protocatechuic aldehyde, protocatechuic acid and kojic acid showed a significant proliferative effect on osteoblasts.

Prevalence and risk factors of peripheral arterial diseases in male Chinese octogenarians and nonagenarians with hypertension / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the prevalence and risk factors of peripheral arterial disease (PAD) in male Chinese octogenarians and nonagenarians with hypertension.</p><p><b>METHODS</b>Ankle-brachial index (ABI) was measured in the noninvasive vascular laboratory for hypertensive male octogenarians and nonagenarians enrolled from outpatient and inpatient departments. The baseline conditions were investigated using standard questionnaire and by routine physical examinations. PAD was diagnosed when an ABI≤0.9 in either lower extremity.</p><p><b>RESULTS</b>Totally 290 male Chinese octogenarians and nonagenarians [age: (84.61±4.20) years] with hypertension who were receiving antihypertensive therapy were enrolled in this study, among whom 9 men with missing data except age and ABI measurements. The ABI was 0.948±0.258, with the range of highest frequency of 0.91-1.30, and 106 patients were diagnosed as PAD, 182 as non-PAD, and 2 had ABI>1.3. ABI in hypertensive men with PAD were significantly lower than in those without PAD (P<0.05). On the contrary, age, blood urea nitrogen, white blood cell counts, platelets and aspartic transaminase were significantly higher in PAD patients than in non-PAD patients (all P<0.05). The prevalence of PAD in this study population were 36.5%; more specifically, it significantly differed between different subgroups when stratified by age (28.6% vs. 46.3%, below and above 85 years), with and without hypertension (27.5% vs. 40.1%), stroke (44.7% vs. 27.5%), dyslipidemia (41.4% vs. 33.3%), coronary artery disease (44.1% vs. 13.9%), and diabetes mellitus (53.7% vs. 21.8%) (all P<0.05). The prevalences of PAD in hypertensive patients treated with diuretics, calcium antagonists, beta-blocker, or angiotensin receptor antagonist were 41.4%, 36.1%, 22.4%, and 26.8%, respectively. No association was observed between the prevalence of PAD and smoking/alcohol drinking in these subjects. Multivariate analysis showed that age (OR 1.12, 95%CI 1.014-1.238), blood urea nitrogen (OR 1.15, 95%CI 1.025-1.301), aspartic transaminase (OR 1.05, 95%CI 1.005-1.089), diabetes mellitus (OR 4.02, 95%CI 1.797-9.009), coronary artery disease (OR 6.34, 95%CI 1.734-23.214) were strong risk factors of PAD.</p><p><b>CONCLUSION</b>PAD is highly prevalent among aged Chinese hypertensive men, in which age, blood urea nitrogen, aspartic transaminase, diabetes mellitus, coronary artery disease may be involved in the development of this condition.</p>

Correlation between DNA methylation of the ABO gene promoter CpG island and leukemia / 中国实验血液学杂志

Recent studies have found that ABO blood group antigen is also closely related to the onset and development of many diseases. More and more attention is being paid to the decrease of A/B blood group antigen caused by some tumors. This study was purpose to investigate the correlation between DNA methylation of the ABO gene promoter CpG island and leukemia. The relative contents of ABH antigen on the surface of RBC from kinds of blood disease patients and healthy individuals were detected by using flow cytometry and confocal laser scanning microscopy. The DNA sequences and CpG methylation of ABO gene promoter in patients with hematopathy and healthy individuals, as well as the -102 site methylation of ABO gene promoter in patients with hematopathy and healthy individuals were detected by PCR and MSP-PCR respectively. The results showed that RBC from leukemia patients displayed different degree of A/B antigen decrease. The sequences of ABO gene promotor of patients with hematopathy were not different from healthy individuals indicating high conservation of promoter sequences. Comparison of sequences between patients with hematopathy and healthy individual indicated that CpG islands on ABO gene promoter either from blood disease patients or from healthy individual had no methylated site in AA patients, but C residues at position -102, -101, -100, -99 and -97 on the promoter of ABO gene in AML, CML, ALL and some MDS patients were methylated. It is concluded that methylation of CpG islands in promoter of ABO gene may result in AB antigen decrease in patients with leukemia. The methylation sites -102, -101, -100, -99 and -97 may be specific for leukemia. The methylation of site -102 can be used as a molecular marker in differential diagnosis for leukemias.

Enhancing transfection efficiency of polyethylenimine by a hydrophobic peptide from bee venom / 中国实验血液学杂志

The study was aimed to investigate the possibility of enhancing transfection efficiency of branched polyethylenimine (BPEI) in HeLa cells by hydrophobic tail of bee venom peptide (melittin). Hydrophobic tail of melittin was synthesized and its membrane permeable activity was evaluated by hemolysis test. The peptide was mixed with BPEI and the transfection efficiency was determined in HeLa cells by using green fluorescent protein gene (GFP) as a reporter gene. The cytotoxicity of the mixture was analyzed by MTT assay at 24 hours after transfection. The results indicated that the synthesized peptide had permeable activity leading to hemolysis in both neutral and acidic solution. At optimal condition, the peptide could significantly improve the transfection efficiency of BPEI and the cytotoxicity of the mixture was lower than BPEI itself. It is concluded that hydrophobic tail of melittin may be a potential enhancer to improve transfection efficiency mediated by cationic polymers in difficult to transfect cells.

B to O erythrocyte conversion by the recombinant alpha-galactosidase / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human group O red blood cells have great benefit in specialized transfusion areas such as armed conflict and natural calamity. The group B antigen differs structurally from group O antigen only by the addition of one terminal alpha-linked galactose residue. In this study we aimed to remove the terminal galactose from group B red blood cell to get group O red blood cell.</p><p><b>METHODS</b>alpha-galactosidase cDNA was cloned by RT-PCR from Catimor coffee beans grown on Hainan Island of China. The vector for alpha-galactosidase cDNA expression was constructed and transferred into Pichia pastoris cells by electroporation. The transgenic cells were cloned by fermentation and the recombinant alpha-galactosidase was purified by ion exchange chromatography. After studying the biochemical characters of alpha-galactosidase, we have used it in converting human erythrocytes from group B to group O.</p><p><b>RESULTS</b>The purity of recombinant alpha-galactosidase was higher than 96%, which was thought to be suitable for the use of blood conversion. Enzymatically converted human group O red blood cells (ECHORBC) exhibited membrane integrity, metabolic integrity, normal cell deformation and morphology. There were no coagulation between ECHORBC and any group of human blood. The ECHORBC will keep normal structure and function for a period of 21 days at 4 degrees C in monoammoniumphosphate nutrient solution. Experiments with Rhesus monkeys and gibbons showed that transfusion of enzymatically converted erythrocytes was safe.</p><p><b>CONCLUSION</b>ECHORBC can be easily obtained from group B red blood cell by alpha-galactosidase digestion. This study suggests that ECHORBC could be transfused to patients safely and efficiently.</p>

Rh antigen stability of mPEG modified red blood cells / 中国实验血液学杂志

The objective of study was to investigate the Rh antigen stability of mPEG-modified RBC. RBC membrane protein SDS-PAGE technology was used to analyze the combination of the mPEG modified RBC membrane protein with mPEG molecules; the RBC ghost coagulation test and 4 degrees C CPD-preserved modified RBC mixed with matched blood were used to observe the stability of RBC Rh antigen camouflaged by mPEG. The results showed that the blood groups of stored mPEG-modified RBC were kept consistency before or after simulating transfusion, i.e. mixture of modified RBC with matched bloods, while the plasma hemoglobin after simulating transfusion was not only within the normal range during the storage, but also less than that before simulating transfusion even after incubation at 37 degrees C. The electrophoresis pattern stained with iodine and Coomassie blue displayed the bands of mPEG combined with RBC membrane protein and the slow mobility of membrane protein. The hemagglutination of PEGylation RBC ghosts did not take place and mPEG still covered the antigen. In conclusion, mPEG-SPA can bind the erythrocyte with its extracted membrane protein in both ghosts and living erythrocytes.

Preliminary study on xenotransfusion from porcine red blood cell into Rhesus monkey / 中国实验血液学杂志

In order to study the possibility of xenotransfusion from porcine red blood cell (pRBC) to primate, the antigens on pRBC surface were modified to make it more compatible to primate sera. Porcine RBCs were subjected to both enzymatic removal of membrane alpha-Gal antigens with recombinant alpha-galactosidase (AGL) and covalent attachment of succinimid propionate-linked methoxypolyethyleneglycol (mPEG-SPA) to camouflage non-alphaGal antigens. The effects of double modifications were determinated by hemagglutination and clinical cross-match testing with rhesus sera. In vivo clearance rates and safety of modified pRBCs were measured after it was transfused into Rhesus monkey with or without immunosuppressant treatment. The validity of pRBC was detected in exsanguine Rhesus monkey model. The results showed that AGL could effectively remove alpha-Gal xenoantigens on pRBC membrane and reduce hemagglutination. The combination of mPEG modification with AGL treatment could significantly increased compatibility between pRBCs and Rhesus monkey sera. Modified pRBCs were detectable in Rhesus monkey blood at 12 hours after transfusion, and their survival time was 40 hours in the immunosuppressant-treated Rhesus monkey. In vivo survival rates of pRBCs were 38% in exsanguine Rhesus monkey at 8 hours after transfusion, and during that time, the hemoglobin and hematocrit of Rhesus monkey were maintained at the same level as before it lost blood. It is concluded that the modified pRBC can be safely transfused into Rhesus monkey and relieve the anemic symptom exsanguine Rhesus monkey. It suggested that pRBC can be hopefully used as a blood substitute for primate and human in the future.

Animal trials for mPEG-modified red blood cells / 中国实验血液学杂志

This study was aimed to investigate the survival rate and difference of transfused modified and unmodified RBC at 24 hours. The modified and unmodified RBC from mice, monkey, pig and human were labeled by using FITC, then these blood RBCs were transfused to homogeneous and heterogeneous animals. The result showed that 24 hour survival rate of unmodified mice RBC transfused to mice was 74%, while survival rate of 2.0 mmol/L mPEG-SPA modified mice RBC transfused to mice was 45%, difference between them was significant. The 24 hour survived rate of unmodified human RBC transfused to mice was 8%, while 24 hours survival rate of 2.0 mmol/L mPEG-SPA modified human RBC transfused to mice was 5% without statistical difference. The 24 hour survived rate of homogeneous transfusion of modified monkey RBC was 90%, while survival rate of modified human and pig RBC was zero on 24 hours after transfusion to monkey. It is concluded that RBC labeling methods and mice species are unrelated to 24 hours survival rate, but mPEG variety and concentration are related to mouse RBC life-span. It is incredible to use mouse RBC homogeneous transfusion result instead of human RBC to evaluate longevity and safety of modified human RBC. But modified human RBC transfused to mice can be a model to evaluate longevity of modified human RBC. It is very difficult to get the result about modified RBC life span by RBC transfusion among great heterogeneous mammal animals. So evaluation in large mammal animal models needs to be further studied.

Preparation of transfusable human universal red blood cell with recombinant alpha-galactosidase / 中国实验血液学杂志

In order to meet the demand for safe transfusion in special conditions and to utilize the donated blood supply efficiently, technology has been developed to convert erythrocytes from type A, B, or AB to "universal donor" blood. Conversion of blood type B to O was performed by means of recombinant alpha-galactosidase digestion. The results showed that blood type B to O was converted successfully, 1 transfusion unit of red cells of group B (100 ml totally) could converted to universal blood cells in the optimal conditions including pH 5.6, 26 degrees C, 2 hours, obturation and sterilization. It is concluded that the universal red blood cells converted from group B to group O are conformed to demand of identification rules of biological products, no harmful effects of alpha-galactosidase on cell structure and function are observed. The converted red cells can stored in 4 degrees C for 21 days.

A pilot study on establishment of human/pig hematopoietic chimera model in fetal and neonatal pigs / 中国实验血液学杂志

This study was aimed to explore the feasibility of transplanting human cord blood stem cells (HSC) into pre-immune fetal and neonatal pigs, and to investigate the self-renewal of HSC in the recipient pigs. The fetus and neonate were manipulated in sterile separated room and human donor cells were injected into fetus via fetus muscle or umbilical vein (dissectted womb) or into neonate via umbilical vein before cutting it. Human CD45(+) cells s were detected by labeling with human anti-CD45 antibody and analyzed by fluorescence activated cell sorting (FACS). The results showed that tested pigs developed as well as control and a definite proportion of human cells existed in peripheral blood of chimeric pig on day 60 after transplantation. In conclusion, the fetus and neonate pigs can tolerate a definite proportion of human antigens, and to establish the human/pig model of hematopoietic chimerism is possible.

Effect of human plasma on preservation of red blood cells / 中国实验血液学杂志

In order to study whether plasma can affect the structure and function of red blood cells during their storage period, the differences of pH value, concentration of K(+), Na(+), osmotic fragility, plasma hemoglobin, AchE, ATP, 2.3-DPG, P50 in suspended RBC, washed RBC, and RBC with various plasma volume at different storage times were compared. The results showed that plasma helped the blood to keep the RBC at high pH value, low K(+), high Na(+) and maintain RBC-ATP, oxygen carry capacity and deformability, but no effect on maintenance of osmotic fragility, and levels of plasma hemoglobin, AchE, ATP and 2.3-DPG was found in preservated blood. In conclusion, human plasma may be in favour of the preservation of red blood cells.

Comparison of modification of surface xenoantigens on bovine and porcine erythrocytes / 中国实验血液学杂志

This study was aimed to explore impact of removal of cell membrane G alalpha1-3Gal beta1-4Glc NAc epitopes (called alpha-Gal) and chemical modification of other xenoantigen on bovine red blood cell (bRBC) and porcine red blood cell (pRBC) antigenicity and to compare their modified erythrocytes, in order to provide basis for development of human blood substitute with rich source, high safety and efficacy. bRBC and pRBC were subjected to both enzymatic removal of membrane alpha-Gal with recombinant coffee bean alpha-galactosidase (rC alpha-GalE) and covalent attachment of benzotriazole carbonate-linked methoxypolyethylene glycol (mPEG-BTC, MW = 20 kD). The effects of treatment were measured by hemagglutination, flow cytometric assay of IgG binding and clinical cross-match testing to human sera. The results showed that although alpha-galactosidase treatment reduced hemagglutination titers to levels similar to negative control, the combination of the treatments was most effective. Clinically used cross-match tests between bRBC, pRBC and human sera demonstrated increased compatibility. Bovine RBC were more robust than pRBC, and had less xenoantigens, and had longer half life than pRBC in vivo. These characteristics suggested that bRBCs were more suitable to investigation as an alternatives to hRBC in clinical transfusion than pRBC. These data suggested that strategies to remove or mask xenoantigens on bRBC reduce antigenicity sufficiently to allow in vitro cross-match compatibility to human sera, and therefore bRBC following modification may be considered as human blood substitute.

Preliminary in vitro study on modification of RBC with mPEG-BTC for resolving the problem of clinical difficulty in blood matching / 中国实验血液学杂志

The aim of this study was to find an effective solution for difficulty of blood matching. Twenty nine cases with clinical difficult in blood matching were collected, classified by their etiological factors, and analyzed with all the antibodies in serum. RBC from health donor were incubated with mPEG-BTC at 25 degrees C for 1 hour. The coagulation of patient serum and donor RBC before and after mPEG-BTC camouflage was detected and compared by polybrene and antihuman globulin reagents. The result showed that 29 cases with difficult blood matching mainly suffered form blood diseases and tumors. The main antibody were Rh and autoantibody. Donor RBC modified by mPEG showed no coagulation with the blood serum in the patients with problems of blood matching. In conclusion, the modification of RBC with mPEG-BTC provides a useful strategy for resolving problem of clinical difficulty in blood matching.

Fermentation and purification of recombinant alpha-galactosidase from Pichia pastoris / 生物工程学报

In order to obtain an adequate supply of alpha-galactosidase for research and practical use, the fermentation, purification and identification of the recombinant coffee bean a-galactosidase were carried out. Baffled flasks containing 100mL BMGY were inoculated with the pPIC9K-Gal/GS115 strain and allowed to grow at 30 degrees C, 250- 300r/min until a maximum optical density at 600nm (OD600) between 2.0 to 6.0 was attained. Entire 400 mL seed culture was transferred aseptically to the 5-liter fermenter, which contained 4 liter sterilized basal salts medium and 4% glycerol. The batch culture grew at 30 degrees C, pH 5.0 until the glycerol was completely consumed, and a glycerol feed was initiated to increase the cell biomass prior to induction with methanol. The culture was centrifuged at 8000 x g and the supernatant was collected. Following ultrafiltration, the retentate was balanced in 20 mmol/L sodium formicate buffer, pH 3.8 and loaded onto a cation-exchange column, HiTrap SP. The column was washed with the same buffer and bound proteins were eluted with 1 mol/L NaCl. The fractions containing recombinant a-galactosidase were pooled and concentrated with PEG20 000. Subsequently, the biochemical properties of the enzyme were determined with typical methods. At last, the fresh human blood A and B erythrocytes were incubated with the purified alpha-galactosidase at 26 degrees C for 2 4 hours. Hemagglutinins were assayed by the standard method. After an elapsed fermentation times (EFT) of 18h, the fed-batch phase was initiated to increase the cell biomass. A cellular yield of nearly 200 g/liter wet cells was achieved when induction was initiated. 72h later, the alpha-galactosidase activity against artificial substrate PNPG (PNP-alpha-galactopyranoside) achieved 36 000u per liter culture. The crude fementation supernatant contained few impurities as detected by SDS-PAGE. The supernatant was purified by cation-exchange chromatography, the target alpha-galactosidase was eluted with 40% 1mol/L NaCl and showed a 41kD band on SDS-PAGE. After concentration, the final recovery was about 41%. The Michaelis constant of the recombinant alpha-galactosidase was determined as 0.275 mmol/L, which slightly lower than the nature enzyme and suggested a higher affinity with specific substrate. When human blood type B erythrocytes pretreated with 100u/mL recombinant alpha-galactosidase reacted with bood type B antiserum, no hemagglutination occurred. This suggested that the B antigens had been removed by the enzyme successfully. These results demonstrated that the recombinant alpha-galactosidase could be produced in largescale and made it possible to explore the application of alpha-galactosidase in more fields.

Camouflage of HLA-I antigen in lymphocyte surface / 中国实验血液学杂志

The objective of this study was to investigate the method and effect of blocking the specific reaction between lymphocyte HLA-I antigen and its antibody. The lymphocytes were disposed with 12 mmol/L methoxypolyethelene glycol benzotriazol carbonate (mPEG-BTC) in concentration gradient in PBS (pH 7.4) at 22 degrees C. The effect of the modified lymphocytes was detected by microlymphocytotoxicity assay. The results showed that lymphocytes modified by mPEG-BTC did not react with related HLA-I antibodies in microcytotoxicity test. It is suggested that the specific reaction between HLA-I antigen of lymphocyte and HLA-I antibodies can be completely camouflaged by mPEG-BTC in PBS (pH 7.4) under 22 degrees C room temperature.