[Research on the negative immune regulation of NK cells in patients with primary immune thrombocytopenia]

目的

探讨原发免疫性血小板减少症（ITP）患者外周血中NK细胞及其相关细胞因子IFN-γ、IL-10、TGF-β的变化。

方法

以22例初诊ITP患者（初诊组）、20例治疗后完全缓解ITP患者（完全缓解组）为研究对象，以20名健康志愿者为对照组。采用ELISA法检测三组受试者血清IFN-γ及IL-10水平；用流式细胞术检测NK细胞（CD3⁻CD56⁺）及其Bright亚群（CD3⁻CD56^bright CD16⁻）、Dim亚群（CD3⁻CD56^dim CD16⁺）水平；采用免疫磁珠法分离NK细胞，实时荧光定量PCR检测IFN-γ、IL-10、TGF-β基因mRNA的表达，并将以上测得结果做相关性分析。

结果

①初诊组ITP患者血清IFN-γ浓度[（653.0±221.6）ng/L]高于完全缓解组[（484.4±219.5）ng/L]和对照组[（390.9±253.5）ng/L]（P值分别为0.022、0.001），血清IL-10浓度低于对照组[（52.09±26.66）ng/L对（79.44±38.43）ng/L，P=0.007]。②初诊组、完全缓解组患者外周血NK细胞比例[（9.53±3.93）%、（9.03±3.78）%]均低于对照组[（13.72±7.42）%]（P=0.013，P=0.007）；初诊患者外周血Bright亚群占NK细胞的比例高于对照组[（6.85±4.43）%对（4.05±2.81）%，P=0.032]；初诊组外周血Dim亚群占NK细胞的比例低于对照组[（93.14±4.43）%对（95.94±2.81）%，P=0.032]。③初诊组、完全缓解组及对照组NK细胞IFN-γ基因mRNA表达差异无统计学意义（P>0.05），初诊组NK细胞IL-10、TGF-β基因mRNA表达高于对照组（1.82±1.32对1.02±1.03，P=0.023；2.80±2.31对1.46±1.37，P=0.028）。外周血Bright细胞占NK细胞的比例与NK细胞IL-10及TGF-β基因mRNA表达呈正相关（r=0.424，P=0.001；r=0.432，P<0.001）。

结论

NK细胞可能通过加强分泌免疫负调控因子来代偿其数量的不足，在疾病中起保护作用。

[Quantities and function of NK cells in patients with immune thrombocytopenia]

Objective: To investigate natural killer (NK) cell quantities and function in patients with immune thrombocytopenia (ITP) . Methods: A total of 66 ITP patients (34 newly diagnosed and 32 in complete remission) were collected from September 2015 to May 2016 in Tianjin Medical University General Hospital, and 30 healthy volunteers were recruited as controls. The percentages of NK cells and their subsets in peripheral blood, the expression of activating receptor (NKp44), inhibitory receptor (NKG2A) and CD16, perforin and granzyme β were detected by flow cytometry. The correlation between the above parameters and patients' immune status and platelet level were evaluated. Results: (1)The percentage of CD3(-)CD56(+) NK cells in newly diagnosed patients (10.99%±4.89%)and patients in complete remission (9.73%±6.75%) were significantly lower than that in healthy controls (14.67%±7.24%)(P=0.023, 0.003). The percentage of NK cells Bright subset was significantly lower in the newly diagnosed patients(0.48%±0.23%)and those in complete remission (0.41%±0.33%) than in healthy controls(0.64%±0.32%)(P=0.037, 0.002); the percentage of Dim subset was also significantly lower in the newly diagnosed (10.16%±5.02%) and patients in complete remission (8.07%±5.74%) than in healthy controls(14.16%±7.19%) (P=0.009, 0.007). (2)The proportion of Bright subset in total NK cells in new diagnosed ITP patients (6.48%±4.33%) was significantly higher than that in healthy controls (4.21%±2.70%)(P=0.020); the proportion of Dim NK cells subset in new diagnosed ITP patients (93.51%±4.33%) was significantly lower than that in healthy controls(95.79%±2.70%) (P=0.020). (3)The expression of activating receptor NKp44 in new diagnosed ITP patients was significantly lower than that in complete remission group and healthy controls[0.28%(0.95%)vs 0.61%(2.05%), 0.92%(0.90%); P=0.047, 0.048]; the expression of inhibitory receptor NKG2A in new diagnosed ITP patients was significantly higher than that in healthy controls(42.34%±23.86% vs 29.25%±12.83%, P=0.009). The proportion of CD16 was significantly lower in the newly diagnosed patients than in healthy controls(93.51%±4.33%95.79%±2.70%, P=0.020). (4)The expression of perforin in the newly diagnosed ITP patients was significantly lower than that in healthy controls [87.52%(25.29%)vs 91.55%(8.29%), P=0.025]; the expression of granzyme β in ITP patients and controls showed no statistically significant difference. (5)The level of NK cells in ITP patients was negatively correlated with CD3(+) CD8(+) T cells (r=-0.387, P=0.012) and CD5(+) CD19(+) B cells in peripheral blood (r=-0.273, P=0.028), positively correlated with the ratio of CD3(+) CD4(+) /CD3(+) CD8(+) (r=0.358, P=0.028) and peripheral platelet count (r=0.314, P=0.011). Conclusion: Deceased quantities and impaired total NK function, insufficient suppression of autoreactive T and B cells might play a role in the pathogenesis of ITP.

[Target cells of cytotoxic T cells in severe aplastic anemia in vitro]

OBJECTIVE

To clarify the specific target of severe aplastic anemia (SAA) immune attack via identifying the target cells of cytotoxic T cell attacks and the expression of apoptosis ligand on each department and each stage of bone marrow hematopoietic cells.

METHODS

A total of 15 SAA patients and 15 normal controls were recruited in the Department of Hematology, Tianjin Medical University General Hospital between March 2011 and March 2012. Factor associated suicide(Fas) protein expression of CD34(+) , CD14(+) , CD33(+) , and GlycoA(+) cells in bone marrow was detected by flow cytometry. The CD8(+) T cells of SAA patients and CD3(-) bone marrow mononuclear cells (BMMNC) of controls were sorted by immunomagnetic separation and co-cultured for 72 hours. The apoptosis rate of CD34(+) , CD14(+) , CD33(+) , and GlycoA(+) cells were measured with flow cytometry.

RESULTS

The expression of Fas protein in CD34(+) cells in SAA patients (46.59%± 27.60%) was significantly higher than that in control group (8.89%±7.28%, P<0.01). The expressions of Fas protein in CD14(+) , CD33(+) and GlycoA(+) cells in SAA group(29.29%±9.23%, 46.88%±14.30%, 15.15%±9.26%) were lower than those in control group(51.25%±38.36%, 72.06%±39.88%, 50.38%±39.88%, all P<0.05). The apoptosis rates of CD34(+) , CD33(+) and CD14(+) cells in the experimental group (CD8(+) T cells of SAA patients co-cultured with CD3(-) BMMNC of controls: 55.43%±20.50%, 38.13%±20.10%, 61.87%±21.65%)were significantly higher than those of the control group (CD8(+) T cells of controls co-cultured with CD3(-) BMMNC of controls: 35.02%±13.95%, 23.44%±10.33%, 37.04%±22.41%, all P<0.05).

CONCLUSIONS

Cytotoxic T cells in SAA patients may have a killing effect on hematopoietic stem/progenitor cells, and granulocytic and macrophagocytic cells from normal bone marrow. Moreover, Fas/Fas ligand-mediated apoptosis may play an important role in the immune pathogenesis of SAA. CD34(+) cells show markedly increased Fas protein expression, which may be the main target cells in the process of immune injury in SAA patients.

Identification of mutations in the F8 and F9 gene in families with haemophilia using targeted high-throughput sequencing

INTRODUCTION

At present, many methods are available for the genetic diagnosis of haemophilia, including indirect linkage analysis, direct sequencing. However, these methods are time-consuming, labourious, and limited in their application. Therefore, the development of new, more effective techniques is necessary.

AIM

To detect the F8 and F9 gene mutations in patients with haemophilia and their female relatives in 29 haemophilia A (HA) and 11 haemophilia B (HB) families.

METHODS

FVIII

C and FIX:C were analyzed using one-stage method, and factor VIII and factor IX inhibitors were tested using the Bethesda method. Intron 22 and one inversions were identified using long-distance polymerase chain reaction (PCR) and standard PCR. Non-inversion mutations of the F8 and F9 gene were identified by targeted high-throughput sequencing. All mutations were verified by Sanger sequencing.

RESULTS

Intron 22 inversion was detected in eight HA families and intron one inversion was detected in one HA family. Apart from the inversion mutations, 20 mutations were identified in HA families, including 17 previously reported and three novel mutations: c.5724G>A (p.Trp1908*), c.6116-1_6120delGAGTGTinsTCC (p.Lys2039Ilefs*13), and c.5220-2A>C. We found a complex rearrangement in HA: intron one inversion concomitant with exon one deletion. In HB, eight recurrent mutations were detected, including six missense mutations and two nonsense mutations.

CONCLUSION

Targeted high-throughput sequencing is an effective technique to detect the F8 and F9 gene mutations, especially for the discovery of novel mutations. The method is highly accurate, time-saving and shows great advantage in uncovering large deletion mutations and also in distinguishing the wild-type genotype and heterozygous large deletions.

[Quantities and function of NK cells in patients with positive BMMNC-Coombs test and cytopenia]

OBJECTIVE

To test NK cell quantities and function in patients with positive BMMNC-Coombs test (CBCPC) and cytopenia and to explore how NK cell participate in the progress of this disease.

METHODS

The percentage of CD3(-)CD56(+) NK cell in peripheral blood lymphocytes, the expression of activating receptor (NKG2D, NKp46, NKp44), inhibitory receptor (CD158a, CD158b), perforin and granzyme-β were detected by flow cytometry. All samples were taken from 42 patients (22 newly diagnosed and 20 in remission) and 12 healthy volunteers. The correlation between the above parameters and patients' clinical profile were evaluated.

RESULTS

①The percentage of CD3(-)CD56(+) NK cell in new diagnosed and remission CBCPC patients were significantly lower than that in healthy control [(10.04 ± 5.33)% vs (19.94 ± 7.38)%; (11.62 ± 6.80)% vs (19.94 ± 7.38)%, all P<0.01]. ② The expression of activating receptor NKG2D in new diagnosed CBCPC patients was significantly higher than that in remission group and healthy control [(74.03±18.24)% vs (45.97±29.45)%; (74.03±18.24)% vs (41.89± 15.34)% , P <0.01]. ③The expression of inhibitory receptor CD158a in new diagnosed CBCPC patients was significantly lower than that in remission group and healthy control (median: 3.72% vs 16.10%, P= 0.015; 3.72% vs 11.04%, P=0.025). ④The expression of perforin in new diagnosed and remitted CBCPC patients were significantly higher than that in healthy controls [(75.71±10.14) % vs (57.20±18.85)%, P= 0.018; (77.88±22.82)% vs (57.20±18.85)%, P=0.008]. ⑤The product of NK cell percentage and perforin expression in new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.68±4.54)% vs (12.13±5.19)%, P=0.011; (8.24±5.80)% vs (12.13±5.19)%, P=0.023]. The product of NK cell percentage and granzyme-β expression in the new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.83±5.26)% vs (14.79±8.37)%, P=0.008; (8.37 ± 6.83)% vs (14.79±8.37)%, P=0.012].

CONCLUSION

Deceased quantities and impaired total NK function might play a role in pathogenesis of CBCPC.

[Age-related differences in the clinical symptoms and triggering factors among Chinese patients with acute myocardial infarction]

OBJECTIVE

To analyze the age-related differences in the clinical symptoms and triggering factors among Chinese patients with acute myocardial infarction.

METHODS

Acute myocardial infarction Patients (n=14 854) registered in the China Acute Myocardial Infarction Registry from January 2013 to March 2014 were included in this study. Patients were divided into 4 groups: <55 years old group (3 950 patients), 55-64 years old group (4 361 patients), 65-74 years old group ( 3 759 patients), and ≥75 years old group (2 784 patients). Demographic features, medical history, clinical presentation and triggering factors were obtained via electronic data capture system.

RESULTS

(1)Persistent chest pain and sweat were the major typical symptoms 66.4%(9 863/14 854) and 63.8%(9 471/14 854)) in the whole cohort. Prevalence of persistent chest pain among four groups were 73.8%(2 915/3 950), 69.2%(3 016/4 361), 63.6%(2 394/3 759) and 55.2%(1 538/2 784), and radiating pain among four groups were 36.2%(1 428/3 950), 34.1%(1 487/4 361), 30.9%(1 160/3 759)and 25.9%(722/2 784), and sweat among four groups were 70.0%(2 765/3 950), 66.5%(2 898/4 361), 61.8%%(2 323/3 759)and 53.3%(1 485/2 784), and there were statistical significance for all above symptoms among groups (all P<0.001). (2)triggering factors before acute myocardial infarction could be found in 19.4%(2 879/14 854) of the patients. Prevalence of existed triggering factors among four groups were 23.8%(941/3 950), 21.0%(914/4 361), 16.6%(625/3 759) and 14.3%(399/2 784, P<0.001). Recent excessive unhealthy lifestyles among four groups were 20.8%(196/3 950), 11.9%(109/4 361), 10.1%(63/3 759) and 9.0%(36/2 784) among the 4 groups (P<0.001).

CONCLUSIONS

Persistent chest pain and sweat are absent in nearly half of Chinese patients in ≥75 years old group. Triggering factors prior to acute myocardial infarction could be evidenced in about twenty percent patients, and which are more often in young patients. Clinical Trail Registry: National Institutes of Health，NCT018746.

Hematogones: a sensitive prognostic factor for Chinese adult patients with acute myeloid leukemia

BACKGROUND

Hematogones (hgs) are normal B-lymphocyte precursors that increase in some hematologic diseases. Many studies indicate that hgs might be a favourable prognostic factor. We thus considered it important to determine whether hgs are also a prognostic factor for Chinese adult patients with acute myeloid leukemia (aml) and whether the hg-positive and hg-negative groups show any serologic or phenotypic differences.

METHODS

Chinese adult aml patients (n = 177) who were all initially hg-negative underwent standard chemotherapy and were thereafter divided into hg-positive and hg-negative groups according to hg levels in bone marrow during their first remission.

RESULTS

The follow-up study confirmed that survival duration (both leukemia-free and overall) was significantly greater in the hg-positive group than in the hg-negative group and was accompanied by a lower relapse rate. A retrospective study of patient characteristics at the time of first diagnosis revealed some differences between the hg-positive and the hg-negative groups, including elevations in white blood cells, lactate dehydrogenase, and β2-microglobulin in the hg-negative group. Retrospective phenotypic analysis revealed a significantly lower proportion of abnormal chromosome karyotype and CD34 expression in hg-positive patients. Finally, we evaluated whether additional intensive chemotherapy after standard chemotherapy could further increase hgs.

CONCLUSIONS

The present work verified the validity of hgs as a prognostic factor for Chinese adult patients with aml. Compared with hg-negative patients, hg-positive patients not only experienced longer survival and a lower relapse rate, but they also had some serologic and phenotypic characteristics that are all considered indicators of better outcome. Additional intensive chemotherapy could further increase the level of hgs, which might imply better clinical results.

A single fas gene mutation changes lupus onset, severity, location, and molecular abnormalities in mice

Although genetic predisposition plays a major role in the progression of systemic lupus erythematosus (SLE) and its variation in symptoms, the precise relationships between genetic changes and disease status are not well understood. Here, to demonstrate the effect of a single gene mutation on disease etiology, we examined two mouse models of SLE with the same genetic background but different Fas genes. Mice with the Fas(lpr) gene developed severe SLE with renal dysfunction and inflammatory responses in the lung and kidney. By contrast, mice with the Fas(+) gene showed disease-related abnormalities in the liver and joints. Patterns of inflammatory disease markers differed across organs between the two lines of mice. Fas(lpr) mice showed greater MMP signals in the kidney and IL-11 signals in the lung than Fas(+) mice. Fas(+) mice had higher IL-11 signal intensity in the knee region and higher CXCR4 signal intensity in the liver than Fas(lpr) mice. Our results exemplify the complexity of disease and suggest the need for individualized target-specific treatment regimens. Strengths and Limitations of this Study: Fas gene is a well characterized gene in this disease. The molecular components in human disease need more clinical data.

Novel NPHS1 splice site mutations in a Chinese child with congenital nephrotic syndrome

Congenital nephrotic syndrome (CNS) is defined as heavy proteinuria or nephrotic syndrome occurring before 3 months of age. It is characterized by early onset and progresses to end-stage renal disease. Recently, several genes associated with CNS have been identified, including NPHS1 and NPHS2. Mutations in the NPHS1 gene have been identified in patients with CNS in Finland with relatively high frequency. Thus far, only a few case reports about CNS have described an NPHS1 mutation in China. In this study, mutational analyses of NPHS1 and NPHS2 were performed in a Chinese child with CNS. Mutations were analyzed in all exons and exon/intron boundaries of NPHS1 and NPHS2 in the patient and his parents as well as in 50 unrelated controls using polymerase chain reaction and direct sequencing techniques. No mutations were detected in NPHS2. A novel splice site mutation (IVS11+1G>A) within intron 11 and a missense mutation within exon 8 (c.928G>A) in the NPHS1 gene were detected in the child. The child's mother had normal urinalysis and a c.928G>A (D310N) heterozygous mutation, and his father had normal urinalysis and IVS11+1G>A. These were not identified in the 50 unrelated controls. The novel splice site mutation of IVS11+1G>A and a missense mutation at c.928G>A in NPHS1 were found to cause CNS in this Chinese child.

Mutational analysis of podocyte genes in children with sporadic steroid-resistant nephrotic syndrome

Recent studies have demonstrated that mutations in 4 podocyte genes, NPHS1, NPHS2, CD2AP, and WT1, are associated with the pathogenesis of steroid-resistant nephrotic syndrome (SRNS). Systematic investigation of all 4 genes for sporadic SRNS in China has not been performed. We examined 10 Chinese children with sporadic SRNS who showed no response to immunosuppressive agents and 20 SRNS controls who exhibited a response to prolonged steroid or immunosuppressive treatment and achieved complete remission. We analyzed mutations in the 4 podocyte genes, NPHS1, NPHS2, CD2AP, and WT1. Mutational analysis was performed using polymerase chain reaction and direct sequencing. Of the 10 SRNS children who showed no response to immunosuppressive agents, the compound heterozygous NPHS1 mutations 2677A>G (T893A) and *142T>C were identified in 1 patient, while a heterozygous mutation in WT1, 1180C>T (R394W), was found in another patient. Of the 20 SRNS children showing complete remission who responded to prolonged steroid therapy or immunosuppressive agents, 4 heterozygous NPHS1 mutations, 928G>A, IVS8+30C>T, IVS21+14G>A, and IVS25-23C>T, were identified in 4 patients and a heterozygous CD2AP mutation, IVS7-135G>A, was identified in 1 patient. Our results indicate the necessity of genetic examination for mutations in podocyte genes in Chinese SRNS children who show no response to immunosuppressive agents.

Distinguishing immunorelated haemocytopenia from idiopathic cytopenia of undetermined significance (ICUS): a bone marrow abnormality mediated by autoantibodies

In recent years we have observed that some patients with idiopathic cytopenia of undetermined significance (ICUS) responded well to corticosteroid and high-dose intravenous immunoglobulin treatment, indicating that some cytopenia in ICUS might be mediated by autoantibodies. In this study, we analysed 166 ICUS cases retrospectively, some of which were autoantibodies detected on haemopoietic cells in bone marrow (BM) by BM mononuclear cell (BMMNC)-Coombs test, flow cytometry (FCM), Western blot and immunofluorescence (IF). We found that 25·9% (43 of 166) of the cases had autoantibodies positive verified with BMMNC-Coombs test or FCM analysis, 72·1% (31 of 43) of whom had immunoglobulin (Ig)G autoantibody positive by Western blot. IgG could be detected in the erythroblastic islands on the BM smear of nine (32·1%, nine of 28) ICUS patients with autoantibodies by IF. Of these 43 patients, the median percentage of reticulocytes was 1·79%. More than half the patients had hyper-BM cellularity with a higher percentage of nucleated erythroid cells in the sternum. Total response rates to immunosuppressive therapy at 6, 12, 24 and > 36 months were 46·5% (20 of 43), 75% (30 of 40), 77·4% (24 of 31) and 66·7% (16 of 24), respectively. We termed this group of ICUS cases with autoantibodies as immunorelated haemocytopenia (or BMMNC-Coombs test-positive haemocytopenia).

Fas/FasL in the immune pathogenesis of severe aplastic anemia

Fas/FasL protein expression of bone marrow hematopoietic cells was investigated in severe aplastic anemia (SAA) patients. Fas expression was evaluated in CD34(+), GlycoA(+), CD33(+), and CD14(+) cells labeled with monoclonal antibodies in newly diagnosed and remission SAA patients along with normal controls. FasL expression was evaluated in CD8(+) cells in the same manner. In CD34(+) cells, Fas expression was significantly higher in the newly diagnosed SAA group (46.59 ± 27.60%) than the remission (6.12 ± 3.35%; P < 0.01) and control (8.89 ± 7.28%; P < 0.01) groups. In CD14(+), CD33(+), and GlycoA(+) cells, Fas levels were significantly lower in the newly diagnosed SAA group (29.29 ± 9.23, 46.88 ± 14.30, and 15.15 ± 9.26%, respectively) than in the remission (47.23 ± 31.56, 67.22 ± 34.68, and 43.56 ± 26.85%, respectively; P < 0.05) and normal control (51.25 ± 38.36, 72.06 ± 39.88, 50.38 ± 39.88%, respectively; P < 0.05) groups. FasL expression of CD8(+) cells was significantly higher in the newly diagnosed SAA group (89.53 ± 45.68%) than the remission (56.39 ± 27.94%; P < 0.01) and control (48.63 ± 27.38%; P <0.01) groups. No significant differences were observed between the remission and control groups. FasL expression in CD8(+) T cells was significantly higher in newly diagnosed patients, and CD34(+), CD33(+), CD14(+), and GlycoA(+) cells all showed Fas antigen expression. The Fas/FasL pathway might play an important role in excessive hematopoietic cell apoptosis in SAA bone marrow. Furthermore, CD34(+) cells are likely the main targets of SAA immune injury.

Effect of Astragalus polysaccharides on chronic atrophic gastritis induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats

This study investigated the effect and mechanism of Astragalus polysaccharides (APS) on chronic atrophic gastritis (CAG) induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in rats. Histomorphological, hormone-level, and immunohistochemistry experiments were used to investigate the gastric mucosal injury. Pathological changes were readily found in CAG rats. Compared to the control rats, the CAG rats showed significantly decreased plasma levels of gastrin and somatostatin while their motilin levels increased. Moreover, PGE2 in gastric tissue increased and serum sIgA decreased significantly, while the GSH/GSSG ratio showed no change. Immunohistochemical detection showed that the expression of EGFR, COX-2, and MMP-2 was higher in the gastric tissue of CAG rats. After APS treatment, the gastric morphology of CAG rats improved. APS increased plasma gastrin and somatostatin levels significantly but had no significant effect on the motilin level. APS also decreased tissue PGE2 and increased serum sIgA in CAG rats without affecting the GSH/GSSH ratio. This study suggested that APS had a beneficial effect on CAG rats by deregulating EGFR at its downstream effectors COX-2 and MMP-2.

Effect of prolonged riluzole exposure on cultured motoneurons in a mouse model of ALS

Riluzole is the only FDA-approved drug to treat amyotrophic lateral sclerosis, but its long-term effects on motoneurons are unknown. Therefore, we treated primary mouse spinal cord cultures with 2 μM riluzole for 4-9 days and then used whole cell patch clamp to record the passive and active properties of both wild-type and SOD1(G93A) motoneurons. At this concentration, riluzole blocks >50% of the sodium component of a persistent inward current that plays a major role in determining motoneuron excitability. Prolonged riluzole treatment significantly decreased the amplitude of the persistent inward current. This effect was specific for SOD1(G93A) motoneurons, where the amplitude decreased by 55.4%. In addition, prolonged treatment hyperpolarized the resting membrane potential as well as the voltage onset and voltage maximum of the persistent inward current (∼2-3 mV in each case). These effects appeared to offset one another and resulted in no change in the firing properties. In a subset of cells, acute reapplication of 2 μM riluzole during the recording decreased repetitive firing and the persistent inward current, which is consistent with the normal effects of riluzole. The downregulation of the persistent inward current in response to prolonged riluzole administration is in contrast to the strong upregulation of this same current after descending neuromodulatory drive to the cord is lost following spinal injury. This dichotomy suggests that decreased activation of G protein-coupled pathways can induce upregulation in the persistent inward current but that direct channel block is ineffective.

The response scale for the intellectual disability module of the WHOQOL: 5-point or 3-point?

OBJECTIVE

To deal with the question of whether a 5-point response Likert scale should be changed to a 3-point scale when used in the field testing of people with intellectual disabilities (IDs), which was raised after the pilot study of World Health Organization Quality of Life (WHOQOL)-DIS, a module being developed with the World Health Organization measure of quality of life for disabilities.

METHODS

Three possible ways were used to generate hypothetical data by merging a 5-point scale into a 3-point scale. The analyses were based on both item response theory and classical measurement theory. The partial credit model for polytomous response was performed for item evaluation; the confirmatory factor analysis was used to check construct validity, the Cronbach's alpha for domain reliability, and correlation analyses for the relationship between the 5-point scale and the generated 3-point scale.

RESULTS

Most items with a 5-point response scale had disordered response options and/or unequal-length intervals between successive response options; these deficiencies were removed or improved without decline of validity and reliability in the hypothetical data of 3-point scales.

CONCLUSION

Instead of the 5-point scale, a 3-point scale could be used for IDs in the field test of developing the module WHOQOL-DIS.

C-jun phosphorylation contributes to down regulation of neuronal nitric oxide synthase protein and motoneurons death in injured spinal cords following root-avulsion of the brachial plexus

Previous studies have shown that c-jun and neuronal nitric oxide synthase (nNOS) are both induced in injured motoneurons, but their roles in motoneuron death remain unclear. We hypothesized that nNOS might be the downstream effector of c-jun N-terminal kinase (JNK)/c-jun in avulsion-induced motoneuron death. Here, we found that brachial root-avulsion induced a temporary increase in JNK activity and three- and four-fold increases in phospho-c-jun and c-jun, respectively; however, brachial root-avulsion caused a decrease in nNOS protein expression from 4 h to 14 days post-injury. At 14 days post-injury, almost all nNOS-positive motoneurons were co-localized with phospho-c-jun-positive motoneurons in ipsilateral ventral horns. The JNK inhibitor SP600125, applied immediately post-injury, resulted in an upregulation of nNOS protein both in injured spinal cords and motoneurons and caused a slight alleviation of motoneuron death by inhibiting c-jun phosphorylation at 14 days post-injury. Our results demonstrated that the JNK/c-jun signal transduction pathway is involved in root-avulsion. The inhibition of c-jun phosphorylation prevents nNOS levels from dropping below baseline levels in the spinal cord and partially alleviates motoneuron death following root-avulsion. Therefore, inhibiting c-jun phosphorylation or up-regulating the nNOS protein in injured spinal cords at the early stage might be used in the future as the molecular-target strategies to prevent the motoneurons degeneration in root-avulsion.

Altered postnatal maturation of electrical properties in spinal motoneurons in a mouse model of amyotrophic lateral sclerosis

Spinal motoneurons are highly vulnerable in amyotrophic lateral sclerosis (ALS).Previous research using a standard animal model, the mutant superoxide dismutase-1 (SOD1)mouse, has revealed deficits in many cellular properties throughout its lifespan. The electrical properties underlying motoneuron excitability are some of the earliest to change; starting at 1 week postnatal, persistent inward currents (PICs) mediated by Na+ are upregulated and electrical conductance, a measure of cell size, increases. However, during this period these properties and many others undergo large developmental changes which have not been fully analysed.Therefore, we undertook a systematic analysis of electrical properties in more than 100 normal and mutant SOD1 motoneurons from 0 to 12 days postnatal, the neonatal to juvenile period.We compared normal mice with the most severe SOD1 model, the G93A high-expressor line. We found that the Na+ PIC and the conductance increased during development. However, mutant SOD1 motoneurons showed much greater increases than normal motoneurons; the mean Na+PIC in SOD1 motoneurons was double that of wild-type motoneurons. Additionally, in mutant SOD1 motoneurons the PIC mediated by Ca2+ increased, spike width decreased and the time course of the after-spike after-hyperpolarization shortened. These changes were advances of the normal effects of maturation. Thus, our results show that the development of normal and mutant SOD1 motoneurons follows generally similar patterns, but that the rate of development is accelerated in the mutant SOD1 motoneurons. Statistical analysis of all measured properties indicates that approximately 55% of changes attributed to the G93A SOD1 mutation can be attributed to an increased rate of maturation.

Gamma-secretase-dependent amyloid-beta is increased in Niemann-Pick type C: a cross-sectional study

OBJECTIVE

Niemann-Pick disease type C (NPC) is an inherited disorder characterized by intracellular accumulation of lipids such as cholesterol and glycosphingolipids in endosomes and lysosomes. This accumulation induces progressive degeneration of the nervous system. NPC shows some intriguing similarities with Alzheimer disease (AD), including neurofibrillary tangles, but patients with NPC generally lack amyloid-β (Aβ) plaques. Lipids affect γ-secretase-dependent amyloid precursor protein (APP) metabolism that generates Aβ in vitro, but this has been difficult to prove in vivo. Our aim was to assess the effect of altered lipid constituents in neuronal membranes on amyloidogenic APP processing in humans.

METHODS

We examined Aβ in CSF from patients with NPC (n = 38) and controls (n = 14). CSF was analyzed for Aβ(38), Aβ(40), Aβ(42), α-cleaved soluble APP, β-cleaved soluble APP, total-tau, and phospho-tau.

RESULTS

Aβ release was markedly increased in NPC, with a shift toward the Aβ(42) isoform. Levels of α- and β-cleaved soluble APP were similar in patients and controls. Patients with NPC had increased total-tau. Patients on treatment with miglustat (n = 18), a glucosylceramide synthase blocker, had lower Aβ(42) and total-tau than untreated patients.

CONCLUSION

Increased CSF levels of Aβ(38), Aβ(40), and Aβ(42) and unaltered levels of β-cleaved soluble APP are consistent with increased γ-secretase-dependent Aβ release in the brains of patients with NPC. These results provide the first in vivo evidence that neuronal lipid accumulation facilitates γ-secretase-dependent Aβ production in humans and may be of relevance to AD pathogenesis.

The relationship between endothelial dysfunction and oxidative stress in diabetes and prediabetes

OBJECTIVE

Diabetes mellitus is associated with endothelial dysfunction and oxidative stress (OS). The aim of the present study was to determine whether increased OS and impaired endothelial function, are present in early states of diabetes, such as impaired glucose tolerance (IGT) and impaired fasting glucose (IFG).

METHODS

Brachial artery flow-mediated dilatation (FMD) and nitrate-induced dilatation were measured in 133 subjects with carbohydrate abnormalities (45 IGT, 44 IFG and 44 Type 2 diabetes mellitus) and in 46 subjects with normal glucose tolerance (NGT). Waist circumference, body mass index, blood pressure and fasting lipid profiles were obtained, and glucose and insulin values in response to a 75-g oral glucose load were also measured. Plasma malondialdehyde (MDA) and superoxide dismutase (SOD) activity were determined.

RESULTS

Patients with diabetes and prediabetes had a higher plasma MDA concentration, but a lower plasma SOD activity than the NGT group (p = 0.006) and SOD activity was positively associated with FMD (p = 0.039). FMD were significantly reduced in the groups of subjects with abnormal carbohydrate metabolism compared with the NGT group (p = 0.035). Among the subjects with diabetes and prediabetes, FMD showed a negative correlation with fasting glucose and/or plasma glucose level at 120 min after oral glucose tolerance test (p = 0.028).

CONCLUSIONS

The results showed that endothelial dysfunction and increased OS were present in subjects with IGT and IFG, indicating endothelial damage in these stages.

Comparison between cells and cancer stem-like cells isolated from glioblastoma and astrocytoma on expression of anti-apoptotic and multidrug resistance-associated protein genes

This study is to explore and compare the features of the cells and cancer stem-like cells (CSCs) isolated from both glioblastoma and astrocytoma on expression of anti-apoptotic and multidrug resistance-associated protein (MRP) genes. As a result, the mRNA expression of livin, livinalpha and MRP1 was up-regulated in human CSCs from 2 times to 85 times, but the gene expression of MRP3 was down-regulated from 0.09 times to 0.5 times. After just differentiation the mRNA expression of livin, livinalpha and MRP3 was up-regulated from 9 times to 64 times, but the mRNA expression of MRP1 was down-regulated from 0.01 times to 0.03 times. It is a rare report that glioma stem-like cells can be induced successfully from a grade 2-3 astrocytoma tissue. The properties of glioblastoma and astrocytoma stem-like cells on anti-apoptotic and MRP genes are: anti-apoptotic gene livin and survivin are elevated in CSCs but are the most increased in just differentiated CSCs; MRP1 gene is significantly increased and MRP3 is decreased in CSCs, but when differentiating the MRP3 gene starts a remarkable increase in CSCs; the expression of anti-apoptotic and MRP genes shows no differences between the CSCs isolated from glioblastoma and astrocytoma tissues.

Two independent measurements of Debye lengths in doped nonpolar liquids

Electric current measurements were performed between 2.5 cm x 7.5 cm parallel-plate electrodes separated by 1.2 mm of heptane doped with 0-15% w/w poly(isobutylene succinimide) (PIBS) having a molecular weight of about 1700. The rapid (microsecond) initial charging of the capacitor can be used to infer the dielectric constant of the solution. The much slower decay of current arising from the polarization of electrodes depends on the differential capacitance of the diffuse clouds of charge carriers accumulating next to each electrode and on the ohmic resistance of the fluid. Using the Gouy-Chapman model for the differential capacitance, Debye lengths of 80-600 nm were deduced that decrease with increasing concentration of PIBS. Values of the Debye lengths were confirmed by performing independent measurements of double-layer repulsion between a 6 microm polystyrene (PS) latex sphere and a PS-coated glass plate using total internal reflection microscopy in the same solutions. The charge carriers appear to be inverted PIBS micelles having apparent Stokes diameters of 20-40 nm. Dynamic light scattering reveals a broad distribution of sizes having an intensity-averaged diameter of 15 nm. This smaller size might arise (1) from overestimating the electrophoretic mobility of micelles by treating them as point charges or (2) because charged micelles are larger on average than uncharged micelles. When Faradaic reactions and zeta potentials on the electrodes can be neglected, such current versus time experiments yield values for the Debye length and ionic strength with less effort than force measurements. To obtain the concentration of charge carriers from measurements of conductivity, the mobility of the charge carriers must be known.

DNA vaccine encoding ESAT-6 enhances the protective efficacy of BCG against Mycobacterium tuberculosis infection in mice

ESAT-6 is a protein produced by virulent Mycobacterium tuberculosis but absent in Mycobacterium bovis bacillus Calmette-Guerin (BCG) and is considered as a promising vaccine subunit against tuberculosis. The protective efficacy of a new strategy based on the combination of DNA vaccine encoding ESAT-6 (DNA-E6) and BCG immunization was investigated in the present study. BALB/c mice were immunized with DNA-E6, BCG, DNA-E6 plus BCG, vector plus BCG or vector alone. Three weeks after the last immunization, antigen-specific interferon (IFN)-gamma secreted upon stimulation with BCG-PPD or ESAT-6 protein by splenocytes of the different groups was determined by an ELISA. The immunized mice were challenged intravenously with low-dose virulent M. tuberculosis H37Rv and bacterial load of the infected mice was measured in the spleen and lung 6 weeks later. Pathological changes in the lung were observed by haematoxylin-eosin (HE) or acid-fast staining. Our study demonstrated that ESAT-6-specific IFN-gamma was improved in mice vaccinated with DNA-E6 plus BCG, compared with those mice immunized with BCG alone. The combination of DNA-E6 and BCG resulted in the maximum reduction in bacterial load in both the lung and spleen, and only slight pathological changes were detected in the lung. These results suggested that the combination of DNA-E6 and BCG vaccination could be a better strategy against M. tuberculosis infections in human.