Clinical characteristics of Danon disease / 中华心血管病杂志

Objective: To review the clinical data of 7 patients with Danon disease and analyze their clinical characteristics. Methods: The medical records of 7 patients with Danon disease, who were hospitalized in Peking Union Medical College Hospital of Chinese Academy of Medical Sciences from April 2008 to July 2021, were reviewed and summarized, of which 6 cases were diagnosed as Danon disease by lysosomal-associated membrane protein-2 (LAMP-2) gene mutation detection and 1 case was diagnosed by clinicopathological features. Clinical manifestations, biochemical indexes, electrocardiogram, echocardiography, skeletal muscle and myocardial biopsy and gene detection results were analyzed, and patients received clinical follow-up after discharge. Results: Six patients were male and average age was (15.4±3.5) years and the average follow-up time was (27.7±17.0) months. The main clinical manifestations were myocardial hypertrophy (6/7), decreased myodynamia (2/7) and poor academic performance (3/7). Electrocardiogram features included pre-excitation syndrome (6/7) and left ventricular hypertrophy (7/7). Echocardiography examination evidenced myocardial hypertrophy (6/7), and left ventricular dilatation and systolic dysfunction during the disease course (1/7). The results of skeletal muscle biopsy in 6 patients were consistent with autophagy vacuolar myopathy. Subendocardial myocardial biopsy was performed in 3 patients, and a large amount of glycogen deposition with autophagosome formation was found in cardiomyocytes. LAMP-2 gene was detected in 6 patients, and missense mutations were found in all these patients. During the follow-up period, implantable cardioverter defibrillator implantation was performed in 1 patient because of high atrioventricular block 4 years after diagnosis, and there was no death or hospitalization for cardiovascular events in the other patients. Conclusion: The main clinical manifestations of Danon disease are cardiomyopathy, myopathy and mental retardation. Pre-excitation syndrome is a common electrocardiographic manifestation. Autophagy vacuoles can be seen in skeletal muscle and myocardial pathological biopsies. LAMP-2 gene mutation analysis is helpful in the diagnose of this disease.

Advances in peptidomimetic inhibitors of coronavirus main protease / 药学学报

Coronavirus (CoVs) is a widespread pathogen that can infect humans and animals to cause serious acute and chronic respiratory diseases. Among them, SARS-CoV broke out in 2003, MERS-CoV was discovered and spread widely in 2012, and SARS-CoV-2 emerged at the end of 2019. They all belong to β-coronavirus. Peptidomimetic inhibitors targeting coronavirus main proteases (Mpro, 3CLpro) have attracted much attention because of their broad spectrum and strong antiviral efficacy. In this review, peptidomimetic inhibitors of coronavirus main protease were classified and summarized according to the different "warheads" in design strategy. And also, the molecular structures, biological activity and design ideas of the inhibitors were analyzed and discussed, which is aimed to provide useful reference for further design and development of coronavirus inhibitors.

Clinical and imaging characteristics of patients with primary cardiac angiosarcoma / 中华心血管病杂志

Objective: To investigate the clinical, cardiac imaging characteristics and prognosis of patients with primary cardiac angiosarcoma. Methods: The clinical data of 14 patients hospitalized with primary cardiac angiosarcoma from January 2001 to December 2017 in Peking Union Medical College Hospital were collected and analyzed. Metastatic cardiac angiosarcoma was not included in this study. Patients were followed up post discharge per telephone call or clinical visit. Results: Of the 14 patients, 8 were males and 6 were females, average age was 48 years. The main clinical symptoms were shortness of breath (8/14), hemoptysis (6/14), fever (5/14), chest pain (4/14) and cough (3/14). Imaging examinations showed that the tumors of 8 patients were located in the right heart and 6 in the pericardial cavity. Tumors in the right heart often infiltrate the atrial wall and cause pericardial effusion (7/8). Tumors in the pericardium were characterized by recurrent bloody pericardial effusion (6/6), prone to progressive constrictive pericarditis (3/6), pericardial fluid cytology was often negative (6/6). MRI showed heterogeneous high signal intensity (cauliflower aspect) on T2-weighted image and heterogeneous enhancement with a"sunray" aspect at the perfusion study. At the time of diagnosis, 8 patients developed lung or adrenal metastasis (8/14). The median survival was only 305 days. Conclusions: Primary cardiac angiosarcoma is a rare disease with non-specific clinical manifestation and poor prognosis. Imaging examinations may help diagnosis. The high invasiveness and the easy-to-metastasis feature of the tumor contribute to the poor prognosis of cardiac angiosarcoma.

Reasearch updates of microRNAs in IgA nephropathy / 医学研究生学报

IgA nephropathy (IgAN) is the most common primary glomerulonephritis and is also one of the main causes of the end-stage renal disease. The pathogenesis of IgAN has not yet fully clarified and the clinical manifestations are diverse. At present, there are no specific molecular biomarkers and therapeutic drugs for IgAN, which leads the prognosis quite different among patients. MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the post-transcriptional level and involved in many pivot physiological and pathological processes. Numerous studies have demonstrated that miRNAs were tissue or organ specific and abundantly and stably existed in the peripheral blood as well as human urine. Thus, deregulated miRNAs have the potential as novel candidate biomarkers for many diseases. Recent studies revealed that miRNAs also play important roles in the pathophysiology of renal diseases. The aim of the present review is to highlight recent research updates for the clinical value of miRNAs and their roles participated in the molecular mechanism of IgAN, which may provide new ideas for the diagnosis and treatment of IgAN.

Study on the Levels and Clinical Significance of Serum miR-150 in Children with Nephrotic Syndrome / 现代检验医学杂志

Objective To investigate the levels and clinical significance of serum miR-150 in children with primary nephrotic syndrome(NS).Methods Serum samples were collected from 78 NS children and 79 age-and sex-matched control children in Nanjing General Hospital,Jiangsu Province Hospital of TCM and Nanjing Children Hospital from March 2010 to May 2014.Quantitive Real-time PCR(qRT-PCR)assays were used to determine the concentrations of serum miR-150 in NS and control children.The other lipid and renal function parameters including serum TP,ALB,GLO,TC,TG,Urea,Cr,Uric acid and Uric protein were also assessed.Statistical analyzes were used to evaluate the clinical value of serum miR-150 for NS as well as to assess the clinical association between the levels of serum miR-150 and other clinical parameters.Results The ser-um levels of miR-150 were significantly elevated in NS children[101.4(21.29~336.6)fmol/L(F=3.658,P<0.001)]as compared with controls[34.11(5.53~134.2)fmol/L].ROC curve analysis showed that the area under the receiver operat-ing characteristic curve(AUCROC)was 0.892(95% CI=0.843~0.940).Spearman rank correlations analyzes showed that the levels of serum miR-150 were significantly negatively associated with GLO(r=-0.231,P=0.042)and TG(r=-0.233,P=0.040)in NS children.Multiple linear regression analyses showed that serum miR-150 was independently associ-ated with serum ALB levels(β=0.241,P=0.034;adjusted r2=0.046)after adjustment of other related factors.Further-more,multivariate logistic regression analysis showed that serum miR-150 an independent risk factor for NS after adjusting other factors including age and gender[OR=16.07(95% CI=5.35~48.28),P<0.001].Conclusion The serum levels of miR-150 were markedly elevated in NS children and closely associated with with impaired kidney function as well as lipid pa-rameters,and may have the potential as a novel auxiliary diagnosis marker for assessing the development of NS.

MicroRNAs in seminal plasma: an update / 中华男科学杂志

MicroRNAs (miRNAs), present abundantly in human body fluids, may serve as biomarkers for the diagnosis of a variety of diseases. Recent studies show that they are also abundantly and stably expressed in the seminal plasma of men. Some seminal plasma-specific miRNAs can be used as potential markers for forensic body fluid identification. Furthermore, the expression profile of seminal plasma miRNAs in normal fertile men is quite different from that in idiopathic infertile patients. The specifically altered profile of seminal plasma miRNA is closely related with male infertility and spermatogenic dysfunction and therefore can be used as a novel biomarker for the diagnosis of male infertility. A deeper insight into the specific changes of seminal miRNA may point a new direction in the studies of the molecular mechanisms of male infertility.

A prospective assessment of the diagnostic value of MAIPA test in idiopathic thrombocytopenic purpura / 中华血液学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical significance of MAIPA test in diagnosis of idiopathic thrombocytopenic purpura (ITP) and in the differential diagnosis of antoimmune thrombocytopenias from nonimmune thrombocytopenias.</p><p><b>METHODS</b>A total of 321 thrombocytopenic patients (118 males, 203 females) from 14 centers were studied. A modified monoclonal antibody immobilization of platelet antigen (MAIPA) method was used to detect the platelet glycoprotein-specific autoantibodies (anti-GP IIb/IIIa, anti-GPIb/IX) to double-blindly evaluate its sensitivity and specificity for the diagnosis of ITP and to investigate the impact of the antibodies on platelet count.</p><p><b>RESULTS</b>The results showed that for the diagnosis of ITP, anti-GPIIb/IIIa, anti-GPIb/IX and both of them had the sensitivity of 39.75%, 32.64% and 55.23%; the specificity of 97.56%, 93.94% and 92.68%; the positive predictive value of 97.94%, 93.98% and 95.65%; the negative predictive value of 35.71%, 32.35% and 41.53%; and the total efficiency of 54.51%, 48.29% and 64.80%, respectively. The positivity of the autoantibodies in immune thrombocytopenias was incredibly higher than that in nonimmune thrombocytopenias. The platelet counts in the immune thrombocytopenias with autoantibody positivities were significantly lower than those without the autoantibodies. The platelet counts were negatively correlated with the concentration of the autoantibodies. The levels of anti-GPIIb/IIIa or anti-GPIb/IX or both of them dropped or disappeared in patients being responsive to steroid therapy.</p><p><b>CONCLUSION</b>MAIPA assay is proved to be of great value for the diagnosis of ITP and for differential diagnosis of immune thrombocytopenias from nonimmune thrombocytopenias.</p>

Determination of platelet-associate autoantibodies against platelet-specific receptors by cytometric bead array and its clinical application in idiopathic thrombocytopenic purpura / 中华血液学杂志

<p><b>OBJECTIVE</b>To establish a method for detecting platelet-associate autoantibodies against platelet-specific receptors using cytometric bead array, and compare the clinical usefulness of this method and modified indirect monoclonal antibody immobilization of platelet antigen technique (MAIPA) in the differential diagnosis of idiopathic thrombocytopenic purpura (ITP) from non-immune thrombocytopenic purpura (non-ITP).</p><p><b>METHODS</b>The microbeads were coated with monoclonal antibodies against glycoprotein IIb/IIIa (CD41a), platelets were isolated from blood samples, then platelet lysate was incubated with the coated microbeads, and R-Phycoerythrin-conjugated goat-antihuman IgG polyclonal antibodies, finally analyzed with flow cytometry. GP IIb/IIIa autoantibodies in sample plasma were measured by modified indirect MAIPA at the same time.</p><p><b>RESULTS</b>The individual fluorescence level was calculated as the ratio to the three controls. The mean ratios were 3.36 (range 0.84 - 22.94) in the ITP group, 1.16 (range 0.67 - 5.59) in the non-ITP patient and 1.08 (range 0.72 - 1.76) in the healthy controls. There was a highly significant difference (P <0.01) between the ITP patients and either the non-ITP patients or the normal controls. If the up limit of healthy controls was set as cutoff value, ratio of greater than 1.76 was considered positive. Cytometric bead array had a sensitivity of 71.43%, a specificity of 94.28% and a positive predictive value of 95.24% for the diagnosis of ITP, the sensitivity being higher than that of modified indirect MAIPA' s (5179%) (chi2 = 4.57, P <0.05). The ROC curve showed the discriminative validity of cytometric bead array was 0.916.</p><p><b>CONCLUSION</b>Flow cytometric bead method for detection of platelet-associate autoantibodies against platelet-specific receptors is a more rapid, better reproducibility and higher sensitivity than modified MAIPA, and has a potential value in promoting the diagnosis of ITP and guiding treatment.</p>

Study of fibrinolysis inhibitors in 117 acute leukemia patients / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the clinical significance of fibrinolysis inhibitors including thrombin activatable fibrinolysis inhibitor(TAFI), plasminogen activator inhibitor (PAI) and alpha2-plasmin inhibitor (alpha2-PI) in acute leukemia (AL).</p><p><b>METHODS</b>PAI-1 antigen and TAFI antigen were investigated by enzyme-linked immunosorbent assay and PAI activity, alpha2-PI activity, TAFI activity by chromatography substrate assay in 117 AL patients and 50 normal controls.</p><p><b>RESULTS</b>1) alpha2-PI activities in AL patients were reduced, especially in ALL patients [(96.8 +/- 21.2)%]; 2) PAI-1 antigens in AML patients [(37.8 +/- 9.2) microg/L] were significantly higher than that in normal controls [(33.8 +/- 4.9) microg/L]; 3) PAI-1 antigens in APL [(37.8 +/- 9.0) microg/L] and AML-M5 patients [(39.9 +/- 11.6) microg/L] were higher and TAFI activities in APL patients [(13.3 +/- 4.8) mg/L] were lower than that in normal controls [(16.9 +/- 2.6) mg/L]; 4) PAI-1 antigens of relapsed/refractory patients (39.6 +/- 11.6) microg/L) were significantly elevated; 5) TAFI activities in bleeding patients [(13.2 +/- 5.3) mg/L] were significantly lower than that in normal control as well as non-bleeding patients (17.0 +/- 4.6) mg/L); 6) The severity of bleeding was negatively correlated with TAFI activity (r = - 0.276, P <0.05).</p><p><b>CONCLUSIONS</b>Hyperfibrinolysis caused partially by decrease of alpha2-PI and TAFI activity takes part in the pathogenesis of bleeding in AL.</p>

Expression and significance of NET-1 protein in hepatocellular carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>This study was designed to investigate the expression and significance of NET-1 in hepatocellular carcinoma (HCC) and analyze the relationship between NET-1 gene expression and clinicopathologic factors in HCC.</p><p><b>METHODS</b>NET-1 gene protein expression was detected by Western blot, fluorescence immunocytochemistry, confocal laser scanning microscopy and immunohistochemistry in 8 cases of HCC tissues, human hepatoma cell line SMMC-7721, and paraffin-embeded sections from 130 cases of HCC.</p><p><b>RESULTS</b>NET-1 gene protein expressed in 8 cases of HCC tissues by Western blot. The NET-1 gene protein positively located in the cytoplasm as irregular granules near Golgi apparatus in SMMC-7721cells, detected by fluorescent immunocytochemistry and observed by confocal laser scanning microscopy. The positive rate of NET-1 protein expression revealed by immunohistochemistry was 96.9% in HCC (126/130). NET-1 Protein expression in HCC was clearly correlative with HCC cytological variants, there were pronounced higher expressions in clear cell type, pleomorphic cell type, and sarcomatous change than that in hepatocytic type (P < 0.05). NET-1 Protein expression in HCC was positively correlative with the histopathologic grading, clinical stages and HCC with hepatitis and cirrhosis (P < 0.05), respectively, and negatively correlated with the presence of patches of necrosis (P < 0.05). But NET-1 protein expression was not associated with AFP level, tumor size and growth patterns, respectively.</p><p><b>CONCLUSION</b>NET-1 protein is expressed in cytoplasm of HCC cells as irregular granules near Golgi apparatus. NET-1 gene expression may promote the uncontrolled proliferation and abnormal differentiation in HCC cells.</p>

Involvement of endogenous histamine in modulatory effect of morphine on seizure susceptibility in mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the modulatory effects of morphine on the susceptibility to pentylenetetrazole-induced seizures, and the involvement of endogenous histamine in this process.</p><p><b>METHODS</b>Both the wild-type (WT) mice and histidine decarboxylase (a key enzyme for histamine biosynthesis) deficient (HDC-KO) mice were subcutaneously injected with different doses of morphine, and 1 hour later the pentylenetetrazole solution (1.5 %) was infused into the tail vein at a constant rate of 0.3 ml/min. The minimal dose of pentylenetetrazole (mg/kg) needed to induce myoclonic jerks and clonus convulsion was recorded as the thresholds of seizures.</p><p><b>RESULT</b>In WT mice, morphine dose-dependently decreased the thresholds of both myoclonic jerks and clonus convulsion. In HDC-KO mice, morphine at 10 mg/kg only significantly decreased the threshold of myoclonic jerks from (38.6 +/-2.9)mg/kg to (32.5 +/-0.7)mg/kg, but had no significant effect on the threshold of clonus convulsion [from (51.8 +/-2.1)mg/kg to (47.6 +/-1.2)mg/kg]. In addition, the value of decreased myoclonic jerks (15.8 +/-1.4)% and clonus convulsion (8.3 +/-0.9)% thresholds were much lower in HDC-KO mice than in WT mice [(26.1 +/-2.5)% and (20.8 +/-2.4)%, respectively].</p><p><b>CONCLUSION</b>Morphine can decrease the thresholds of pentylenetetrazole in induction of seizure, and the endogenous histamine may be involved in this process.</p>

Injection of saline into unilateral central piriform cortex inhibits amygdaloid-kindled seizures in rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the effect of microinjection of saline into unilateral central piriform cortex (cPC) on the generalized seizures in amygdaloid-kindled rats.</p><p><b>METHODS</b>Different volumes of saline were injected into the right or left cPC of amygdaloid-kindled rats, and its effect on generalized seizures was observed.</p><p><b>RESULT</b>Saline injection at different volumes 0.1 microl, 0.25 microl and 1 microl) significantly decreased the incidence and duration of generalized seizures (P<0.05), the anticonvulsant effect lasted for up to 10 d. In addition, 10 min after ipsilateral injection of saline the generalized seizure thresholds were significantly increased; while this effect was observed 30 min later when contralateral injection was used.</p><p><b>CONCLUSION</b>Unilateral saline injection into cPC has a significant anticonvulsant effect, which might be used for treatment of human temporal lobe epilepsy in the future.</p>

Important role of Ser 219 phosphorylation of TRF1 in regulation of cell cycle / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the role of Ser 219 phosphorylation of TRF1 (telomere repeat binding factor 1) in regulation of cell cycle.</p><p><b>METHODS</b>The mimicking phosphorylation mutant (TRF1S219D-GFP) and the non-phosphorylatable mutant (TRF1S219A-GFP) were constructed; the mutant genes and corresponding proteins were checked by sequencing and Western blot, respectively. Immunofluorescence staining was performed to detect the localization of mutants in HeLa cells. Cell cycle was analyzed by flow cytometry and ATM level was evaluated by immunoblotting.</p><p><b>RESULTS</b>The mutant genes were verified by direct sequencing and protein expression of GFP-tagged mutants was confirmed by immunoblotting.TRF1S219A-GFP and TRF1S219D-GFP were both localized in telomere of HeLa cells. Moreover, overexpression of TRF1-GFP or TRF1S219A-GFP resulted in an accumulation of HeLa cells in G2/M (P<0.05). The protein level of ATM was increased when overexpression the wide type or mutants.</p><p><b>CONCLUSION</b>The Ser 219 phosphorylation of TRF1 by ATM could result in cell cycle arrest in G2/M, which is related to overexpression of TRF1.</p>

Localization of p53(301-393) mutant and its effect on mitosis / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the localization of p53(301-393)(residues 301-393) in p53 positive/negative cells and its effect on cell mitosis.</p><p><b>METHODS</b>The protein expression of p53-GFP and p53(301-393)-GFP was checked by immunoblotting after transfection. Immunofluorescence staining was performed to detect the localization of wide type and mutant in Hela cells (p53 positive) and H1299 cells (p53 negative). The cell morphology of H1299 cells transfected of p53(301-393)-GFP and the cells in mitotic phase were observed. Cell cycle was analyzed by flow cytometry and p53 protein level in HeLa cells was evaluated by Western blot after transfection of p53-GFP and p53(301-393)-GFP.</p><p><b>RESULTS</b>The protein expression of p53-GFP and p53(301-393)-GFP was verified, p53-GFP was about 90 kMr and p53(301-393)-GFP about 40 kMr. Immunofluorescence microscopy demonstrated that both proteins were diffusely located in the nuclei of HeLa cells and H1299 cells. But different from the p53-GFP, the p53(301-393)-GFP was distributed in the nucleolus of HeLa cells. After transfection of the two plasmids, mitosis was inhibited in H1299 cells and some cells underwent apoptosis. G2/M progression of HeLa cells could be blocked by transfection of p53(301-393)-GFP, but endogenous p53 protein level was not changed.</p><p><b>CONCLUSION</b>p53(301-393)has a different localization in the p53 positive and p53 negative cells and could inhibit mitosis and cause the cell cycle arrest in G2/M.</p>

Interaction between a novel centrosomal protein TACP1 and mitotic kinase Nek2A / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To study interaction between a novel centrosomal protein TACP1 and mitotic kinase Nek2A.</p><p><b>METHODS</b>Nek2A305-446 protein was expressed and purified in E.coli and TACP1 protein was expressed in transfected 293T cells. Pull-down assay was used to examine the interaction between Nek2A305-446 and TACP1. TACP1 and Nek2A complex was tested by co-immunoprecipitation assay with polyclonal anti-TACP1 antibody. The localization of those two proteins in Hela cells was verified by immunofluorescence.</p><p><b>RESULTS</b>TACP1 was pulled down by Nek2A305-446 protein but not by GST control. Nek2A was co-precipitated with TACP1 protein by polyclonal anti-TACP1 antibody but not by pre-immunization serum. The Immunofluorescence test showed that these two proteins formed a complex at centrosome during mitosis.</p><p><b>CONCLUSION</b>Centrosomal protein TACP1 is a novel interacting protein with Nek2A, both of which are localized in centrosome during mitosis.</p>

Effect of chronic transauricular kindled seizures on passive-avoidance test memory retention in rats / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate effect of chronic transauricular kindled seizures on passive-avoidance test memory retention in rats.</p><p><b>METHODS</b>Chronic transauricular kindled seizures was induced by repeated application of initially subconvulsive electrical stimulation through ear-clip electrodes once every 24 h until the occurrence of 3 consecutive clonic-tonic seizures. A passive avoidance test was used to measure memory retention ability. Morphological changes in neurons of hippocampal CA1 region was examined after HE staining. Histamine, gamma-aminobutyric acid (GABA) and glutamate levels in the hippocampus were measured by high performance liquid chromatography (HPLC).</p><p><b>RESULT</b>Chronic transauricular kindled seizures impaired passive-avoidance test memory retention in rats. The damaged CA1 neurons were observed and histamine content in the hippocampus markedly decreased 24 h after the end of kindling in the chronic transauricular kindled rats.</p><p><b>CONCLUSION</b>Chronic transauricular kindled seizure impaired passive-avoidance test memory retention, and it might be due to the damaged CA1 neurons and a decrease of histamine in the hippocampus induced by epilepsy.</p>

The immunoreactivity of IgG and its fragments from ITP patients and their effects on platelet aggregation function / 中华血液学杂志

<p><b>OBJECTIVE</b>To prepare ITP plasma IgG and its F(ab')2 fragments and investigate their immunoreactivity to platelet GPIIb/IIIa and/or GPIb/IX and their effects on platelet aggregation function.</p><p><b>METHODS</b>The ITP patients having inhibitory autoantibody to the platelet aggregation were selected by modified MAIPA and platelet aggregation test with turbidimetry. Plasma IgG and its F(ab')2 fragments were prepared by streptococcal protein A affinity column and pepsin digestion. The immunoreactivity and the effects on platelet aggregation function of the whole antibody and its fragments were detected by modified MAIPA and platelet aggregation test, respectively.</p><p><b>RESULTS</b>(1) Anti-platelet GPIIb/IIIa and/or GPIb/IX autoantibodies were detected in 34 of 68 (53.6%) ITP patients' plasmas and that from 5 patients significantly inhibited the platelet aggregation induced by ADP or ristocetin. (2) By using protein A column combined with protease digestion, pure IgG and its F(ab')2 fragments were successfully obtained. (3) The purified IgG and its F(ab')2 fragments retained the ability to bind to their respective glycoproteins and inhibited the platelet aggregation function, whereas the IgG depleted plasma lost the ability of binding to the platelet GPs.</p><p><b>CONCLUSIONS</b>F(ab')2 fragment of the IgG antibody is a functional fragment, which not only has the binding ability to the platelet GPs but also inhibits the platelet aggregation function in a dose-dependent manner.</p>

Study on the direct MAIPA technique in the differential diagnosis of immune and non-immune thrombocytopenia / 中华血液学杂志

<p><b>OBJECTIVE</b>To evaluate the clinical usefulness of direct monoclonal antibody immobilization of platelet antigen (MAIPA) technique in the differential diagnosis of immune and non-immune thrombocytopenia.</p><p><b>METHODS</b>Platelet-bound autoantibodies in thrombocytopenic patients (immune and non-immune) were measured by direct MAIPA. Monoclonal antibodies against GP II b/III a, GPIb and GP I a/II a were used.</p><p><b>RESULTS</b>The positive rates of platelet-bound GP-specific autoantibodies between immune (76.4%) and non-immune thrombocytopenia (3.6%) were significantly different (P < 0.05). The direct MAIPA had a sensitivity of 76.4%, a specificity of 96.4%, and a positive predictive value of 97.1% for the diagnosis of immune thrombocytopenia. There was a significant inverse correlation between platelet-bound GP II b/III a specific autoantibody levels and platelet counts (r = -0.338, P < 0.05).</p><p><b>CONCLUSION</b>The direct MAIPA technique can be used to differentiate immune from non-immune thrombocytopenias.</p>

Study on the expression and mutation of human telomeric repeat binding factor (hTRF1) in 10 malignant hematopoietic cell lines / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>Detecting the expression and mutation of human telomeric repeat binding factor (hTRF1) in 10 malignant hematopoietic cell line cells on the base of determining its genomic structure and its four pseudogenes to clarify if hTRF1 mutation is one of the factors of the activation of telomerase.</p><p><b>METHODS</b>hTRF1cDNA sequences were obtained from GenBank, its genome structure and pseudogenes were forecasted by BLAST and other biology information programs and then testified by sequencing. Real-time RT-PCR was used to detect the expression of hTRF1mRNA in 10 cell line cells, including myelogenous leukemia cell lines K562, HL-60, U-937, NB4, THP-1, HEL and Dami; lymphoblastic leukemia cell lines 6T-CEM, Jurkat and Raji. Telomerase activities of cells were detected by using telomeric repeat amplification (TRAP)-ELISA protocol. PCR and sequencing were used to detect mutation of each exon of hTRF1 in 10 cell line cells.</p><p><b>RESULTS</b>hTRF1 gene, mapped to 8q13, was divided into 10 exons and spans 38.6 kb. Four processed pseudogenes of hTRF1 located on chromosome 13, 18, 21 and X respectively, was named as PsihTRF1-13, PsihTRF1-18, PsihTRF1-21 and PsihTRF1-X respectively. All cell line cells showed positive telomerase activity. The expression of hTRF1 was significantly lower in malignant hematopoietic cell lines cells (0.0338, 0.0108-0.0749) than in normal mononuclear cells (0.0493, 0.0369-0.128) (P=0.004). But no significant mutation was found in all exons of hTRF1 in 10 cell line cells. Four variants were found in part of intron 1, 2 and 8 of hTRF1. Their infection on gene function is unknown and needs further studies.</p><p><b>CONCLUSION</b>hTRF1 mutation is probably not one of the main factors for telomerase activation in malignant hematopoietic disease.</p>

Localization of human telomere repeat binding factor 1 in telomerase-positive and-negative cells and its expression during cell cycle / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the distribution pattern of human telomere repeat binding factor 1(TRF1) in the telomerase-positive (HeLa) and telomerase-negative cells (WI38-2RA) and to investigate its expression level during the cell cycle.</p><p><b>METHODS</b>The full-length sequences of TRF1(TRF1FL) and its mutant with N and C terminus deletion (TRF1DeltaNC) were generated by PCR amplification, the resulting fragments were cloned into pEGFP-C2 mammalian expression vector. GFP-tagged proteins were verified by Western blotting with rabbit anti-TRF1 and mouse anti-GFP antibodies after cell transfection. Immunofluorescence staining were performed to detect the TRF1 localization in HeLa and WI38-2RA cells. Metaphase spreads from HeLa cells were also prepared to observe TRF1 localization in chromosomes. HeLa cells were arrested by thymidine and nocodazole at different cell stages. Cell cycles were analyzed by flow cytometry and TRF1 levels were evaluated by semi-quantitative Western blotting.</p><p><b>RESULTS</b>TRF1FL and TRF1PNC fragments were sized about 1.3 kb and 0.95 kb. GFP-tagged TRF1FL and TRF1DeltaNC proteins were 80 kD and 60 kD, respectively. In both HeLa and WI38-2RA cells, TRF1FL had a speckled distribution in the nuclei,however, TRF1FL did not coincide with promyelocytic leukemia (PML) nuclear body in HeLa cells while it exclusively did in WI38-2RA cells. Moreover, TRF1FL was exactly localized at the termini of metaphase spreads in HeLa cells. In contrast, TRF1PNC was diffusely distributed throughout the nuclei. Analysis by semi-quantitative Western blotting indicated that TRF1 levels increased with cell cycle progression, which reached the zenith at the M phase and went down to the nadir at G1/S point. The TRF1 level at M phase was about 3.9 times than that at G1/S point(t=12.92iP<0.01).</p><p><b>CONCLUSION</b>TRF1 has a different localization in telomerase-positive and telomerase-negative cells, which suggests TRF1 might exert different functions in these cells. TRF1 level is regulated with cell cycle.</p>