Associations between Sedentary Duration and Cognitive Function in Older Adults: A Longitudinal Study with 2-Year Follow-Up.

OBJECTIVES: This study aimed to investigate the association between different forms of sedentary behavior and cognitive function in Chinese community-dwelling older adults. DESIGN: A longitudinal study with a 2-year follow-up. SETTING AND PARTICIPANTS: Data from 5356 participants at baseline and 956 participants at the follow-up of the Anhui Healthy Longevity Survey (AHLS) were analysed. MEASUREMENTS: Cognitive function was evaluated by the Mini-Mental State Examination (MMSE), and mild cognitive impairment (MCI) was classified according to education-specific criteria. Self-report questionnaires were used to assess the sedentary behavior of the participants. RESULTS: The participants who reported longer screen-watching sedentary duration had higher MMSE scores (1-2 hours: ß=0.758, 95% CI: 0.450, 1.066; > 2 hours: ß=1.240, 95% CI: 0.917, 1.562) and lower likelihoods of MCI (1-2 hours: OR= 0.787, 95% CI: 0.677, 0.914; >2 hours: OR=0.617, 95% CI: 0.524, 0.726). The participants who had played cards (or mahjong) sedentary had higher MMSE scores (ß= 1.132, 95% CI: 0.788, 1.476) and lower likelihoods of MCI (OR=0.572, 95% CI: 0.476, 0.687). However, the participants who reported longer other forms of sedentary duration had lower MMSE scores (1-2 hours: ß=-0.409, 95% CI: -0.735, -0.082; > 2 hours: ß=-1.391, 95% CI: -1.696, -1.087) and higher likelihoods of MCI (1-2 hours: OR=1.271, 95% CI: 1.081, 1.496; > 2 hours: OR=1.632, 95% CI: 1.409, 1.889). No significant association was detected between sedentary duration and MCI incidence. CONCLUSION: Variations in the impact of diverse sedentary behaviors on the cognitive function were detected in Chinese older adults. However, such associations were cross-sectional and longitudinal associations were not found in the current study.

[The expression and clinical significance of neutrophil myeloperoxidase in patients with myeloperoxidase-antineutrophil cytoplasmic antibody associated vasculitis].

Objective: To investigate the expression and clinical significance of neutrophil myeloperoxidase (MPO) in patients with MPO-antibody associated vasculitis (AAV). Methods: Thirty-six newly diagnosed MPO-AAV patients who were hospitalized in the First Affiliated Hospital, Anhui Medical University from July 2018 to June 2021 were enrolled,and 36 age and sex matched healthy subjects were selected as controls. Neutrophil MPO level was detected by flow cytometry (FCM) and MPO mRNA was tested by real time quantitative polymerase chain reaction (RT-qPCR) in all subjects. Serum complement fragment C5 (C5a) and MPO in both groups and serum MPO-anti-antineutrophilic cytoplasmic antibody(ANCA) in MPO-AAV group were measured by enzyme linked immunosorbent assay (ELISA), while the disease activity was evaluated by Birmingham vasculitis activity score-V3 (BVAS-V3). Results: Compared with the heathy control group, the expression of MPO mRNA in neutrophils, serum MPO and complement C5a in MPO-AAV group were significantly higher[MPO mRNA:30.2±11.5 vs. 1.9±0.6, P<0.001;MPO:(112.0±68.7) IU/L vs. (87.4±22.9) IU/L, P=0.01; C5a:(187.3±90.3) ng/ml vs. (107.3±31.1) ng/ml, P<0.001; respectively], while the mean fluorescence intensity (MFI) of MPO in neutrophils were significantly lower [ 1 343.3±723.4 vs. 2 868.0±1 136.5, P<0.001]. In MPO-AAV group, the expression of neutrophil MPO mRNA was positively correlated with serum MPO-ANCA and MPO levels (r=0.537, P=0.001 and r=0.358, P=0.032; respectively). Multiple regression analysis suggested that neutrophil MPO mRNA expression was positively correlated with serum MPO-ANCA level (ß=0.695, P=0.006); neutrophil MPO level was negatively correlated with serum MPO-ANCA, MPO and complement C5a levels (r=-0.335, P=0.046; r=-0.372, P=0.026; r=-0.577, P<0.001; respectively). Further, neutrophil MPO level was negatively correlated with serum complement C5a level (ß=-0.374, P=0.043). BVAS-V3 was positively correlated with MPO mRNA expression in neutrophils, serum MPO-ANCA, MPO and complement C5a (r=0.598, P<0.001; r=0.599, P<0.001; r=0.537, P=0.001; r=0.415, P=0.012; respectively) and negatively correlated with MPO level in neutrophils (r=-0.342, P=0.041). In multiple regression analysis it suggested that BVAS-V3 was positively correlated with MPO mRNA expression in neutrophils (ß=0.511, P=0.002). Conclusion: In MPO-AAV patients, MPO synthesis and release in neutrophils are both significantly increased, which might be influenced by serum MPO-ANCA and C5a, respectively. Furthermore, MPO synthesis activity in neutrophils is an independent factor related to disease activity.

Vegetable and Fruit Intake, Its Patterns, and Cognitive Function: Cross-Sectional Findings among Older Adults in Anhui, China.

OBJECTIVES: To examine the associations of vegetable and fruit intake frequency, its patterns, and cognition among older Chinese adults. DESIGN: Cross-sectional data obtained from the Anhui Province Healthy Longevity Survey. SETTING: Urban and rural communities. PARTICIPANTS: A total of 5410 older adults (aged 60 or older) were included from selected communities. MEASUREMENTS: Data on the number of days in a typical week that vegetables and fruits were consumed were collected, and the four intake patterns were defined (V+/F+: daily intake of both vegetables and fruit; V+/F- or V-/F+: daily intake of vegetables or fruit; and V-/F-: no daily intake of either vegetables or fruit). Cognitive function was measured using the Mini-mental State Examination (MMSE), and mild cognitive impairment (MCI) was defined according to education-specific criteria. RESULTS: Nondaily vegetable intake was associated with lower MMSE scores (ß = -0.763, 95% confidence interval (CI): -1.463, -0.064) among males and a higher likelihood of having MCI (OR: 1.409, 95% CI: 1.037, 1.915) among females. Less frequent intake of fruit was associated with lower MMSE scores and a higher prevalence of MCI among both males and females (p for trends < 0.001 for both sexes). Compared with the V+/F+ group, male participants who were classified into the V+/F- and V-/F- groups had lower MMSE scores (V+/F-: ß = -0.612, 95% CI: -1.094, -0.131; V-/F-: ß = -1.273, 95% CI: -2.090, -0.455). Females classified in the V+/F- and V-/F- patterns had lower MMSE scores (V+/F-: ß = -0.862, 95% CI: -1.320, -0.404; V-/F-: ß = -1.293, 95% CI: -2.079, -0.507) and elevated risks of MCI (V+/F-: OR: 1.762, 95% CI: 1.386, 2.242; V-/F-: OR: 2.180, 95% CI: 1.505, 3.156). CONCLUSION: Lower vegetable or fruit intake was associated with poorer cognitive performance among males and females, and the risk was even higher among those with a low intake of both vegetables and fruits. Healthy eating habits, including daily vegetable and fruit intake, are essential for cognition maintenance in both males and females.

Living Environment, Built Environment and Cognitive Function among Older Chinese Adults: Results from a Cross-Sectional Study.

BACKGROUND: Many studies have addressed the relationship between environmental factors and cognitive function; however, evidence from China is very rare. OBJECTIVES: To discuss the relationship between the living and built environment and cognitive function among older Chinese adults. DESIGN: The Anhui Healthy Longevity Survey (AHLS) was used to investigate the ability to control major non-communicable diseases through behavioural techniques among adults aged 60 or older dwelling in Anhui Province. A multistage sampling strategy was used to obtain a representative sample. Cross-sectional data were collected for the analyses. SETTING: The included participants were recruited from four selected cities in Anhui Province, China. PARTICIPANTS: The participants were adults aged 60 or older and resided in the selected urban or rural communities. MEASUREMENTS: The Mini Mental State Examination was used to measure the cognitive status of the participants. Mild cognitive impairment (MCI) was defined as illiteracy with MMSE scores lower than 18, MMSE scores lower than 21 among those educated for 0-6 years, or MMSE scores lower than 25 among those with 6 or more years of education. The living environment was assessed by asking the participants about their daily living conditions. The distances between the participants' dwellings and the nearest facilities and the proportions of green/blue spaces within 800 m buffers were calculated based on the textural address to indicate the built environment. RESULTS: The male participants who lived in a non-dusty environment had higher MMSE scores (ß=0.828, 95% CI: 0.240, 1.416, p=0.006) and lower risks of mild cognitive impairment (MCI) (OR=0.651, 95% CI: 0.488, 0.868, p=0.003), and the male participants with no access to recreation spaces had lower MMSE scores (ß=-1.107, 95% CI: -1.531, -0.684, p<0.001) and higher risks of MCI (OR=1.403, 95% CI: 1.134, 1.737, p=0.002). The female participants who lived far from a supermarket had significantly lower MMSE scores (Q3:ß=-0.750, 95% CI: -1.266, -0.233, p adjusted=0.036; Q4: ß=-1.184, 95% CI: -1.745, -0.624, p adjusted<0.001) than those who lived near a supermarket (Q1). CONCLUSIONS: The living environment and built environment might have sex-specific associations with cognitive function among older adults.

Knee symptom but not radiographic knee osteoarthritis increases the risk of falls and fractures: results from the Osteoarthritis Initiative.

OBJECTIVE: To describe the effect of knee symptoms and radiographic osteoarthritis (ROA) on the risk of falls, recurrent falls, and fractures. DESIGN: Participants from the Osteoarthritis Initiative were classified as having 'no', 'unilateral' or 'bilateral' knee symptoms (≥19 on a 0-96 Western Ontario and McMaster Universities Osteoarthritis Index) and ROA (Kellgren-Lawrence grade ≥2) for each visit. Self-reported falls and fractures in the past 12 months were extracted at baseline and follow-up visits until month 96. Recurrent falls were defined as having ≥2 falls in the past 12 months. Hazard ratios (HR) with 95% confidence intervals (CI) were estimated using mixed-effects complementary log-log regression. RESULTS: Of 4465 participants, 3145 (70%), 1681 (38%), and 806 (18%) experienced at least one fall, recurrent fall, and fracture, respectively, over 96 months. Compared to participants without symptomatic knee, unilateral and bilateral knee symptoms were associated with a 17% increased risk of falls and a 36-46% increased risk of recurrent falls, and bilateral knee symptoms increased the risk of fractures (HR 1.45, 95%CI 1.17 to 1.81). Compared to participants with no ROA in either knee, bilateral ROA was associated with a reduced risk of falls (HR 0.87, 95%CI 0.77 to 0.99) and fractures (HR 0.78, 95%CI 0.64 to 0.96). No statistically significant interactions between knee symptoms and ROA were observed. CONCLUSIONS: This large population-based study showed that knee symptoms but not ROA increased the risk of falls, recurrent falls, and fractures, and that adults with bilateral ROA may have a lower risk of falls and fractures.

[Recommendations for diagnosis and treatment of primary biliary cholangitis in China (2021)].

Primary biliary cholangitis is a chronic autoimmune cholestatic disease with a progressive course. This disease is not rare in China, but standardized diagnosis and treatment for primary biliary cholangitis are insufficient. Based on the evidence and guidelines from China and other countries, Rheumatology Branch of Chinese Medical Association developed the recommendations of diagnosis and treatment for primary biliary cholangitis in China. The aim is to help clinicians recognize clinical characters, therapeutic selection and prognosis judgement of primary biliary cholangitis, which will contribute to make diagnosis in time, to select treatment properly and to manage follow-up scientifically.

Efficacy and safety of biological agents in the treatment of patients with Takayasu arteritis: a systematic review and meta-analysis.

OBJECTIVE: We aimed to systematically review biological agents' efficacy and safety in patients with Takayasu arteritis (TAK). MATERIALS AND METHODS: A systematic literature search of 7 electronic databases, including MEDLINE (via PubMed), EMBASE, Elsevier ScienceDirect, EBSCO, Springer Link, Web of Science, and Cochrane Library on the efficacy of biological agents on patients with TAK was conducted. Only studies published in English and with a sample size >5 patients with TAK were included. Two reviewers independently selected studies, extracted data and assessed its methodological quality. Random effects meta-analyses of various effect measures were performed. RESULTS: According to the title and abstract, 961 studies were identified and screened. Subsequently, 31 studies from 29 observational studies and 2 randomized-controlled trials (RCTs), which included a total of 517 patients with TAK that met the inclusion and exclusion criteria, were selected. Observational studies showed a high risk of bias. Pooled remission rates of biological agents were 66% (95% CI: 58%-73%; I2=59%), and the remission rates of anti-tumor necrosis factor (TNF) agents and tocilizumab (TCZ) were similar: 65% (95% CI: 56%-73%; I2=49%) and 70% (95% CI: 55%-86%; I2=69%), respectively. Pooled relapse rates were 23% (95% CI: 15%-31%; I2=66%). The relapse rate was 28% (95% CI: 16%-40%; I2=68%) for anti-TNF agents and 17% (95% CI: 7%-26%; I2=49%) for TCZ. The remission rate of TCZ was slightly higher (p>0.05), but the relapse rate was statistically significantly lower than that of anti-TNF agents (p=0.017). Furthermore, biological agents significantly decreased the doses of glucocorticoid (GC) and levels of acute phase inflammation markers (ESR, CRP) while the proportion of patients with new angiographic lesions or progression of previously noted lesions were 11% (95% CI: 4%-18%; I2=59%). RCTs with a small sample size showed abatacept was ineffective, and TCZ was underpowered to detect a difference in time to relapse compared to placebo. The most common adverse event of biological agents was infection (6%, 95%CI: 2%-10%). No deaths were reported. CONCLUSIONS: Although the beneficial effects of biological agents are encouraging in enhancing disease remission, reducing the levels of acute phase inflammation markers and decreasing the treatment doses of GC in patients with TAK, there is still a risk of relapse. More refined studies with larger cohorts are necessary before drawing a definitive opinion.

Detection of CTCs and CSCs in the staging and metastasis of non-small cell lung cancer based on microfluidic chip and the diagnostic significance.

OBJECTIVE: Dynamic monitoring of CTCs/CSCs can assist in the diagnosis and prognosis of tumors. This study explores the diagnostic significance of microfluidic chip technology in the detection of CTCs/CSCs in clinical staging and metastasis of patients with non-small cell lung cancer (NSCLC). That lays a solid foundation for the use of microfluidic chips to monitor CTCs/CSCs for the stage and metastasis of patients with non-small cell lung cancer. PATIENTS AND METHODS: This study collected 80 patients with lung cancer from October 2017 to October 2018. Meanwhile, 30 healthy people and 30 patients with benign lung diseases were selected during the same period as the control group 1 and the control group 2, respectively. CellSearch (Huntington Valley, PA, USA) and microfluidic chip were used to detect CTCs, the sensitivities were recorded. ELISA methods were used to detect the concentrations of tumor markers VEGF-C, CEA, and CA125 in serum, and their association with CTCs and CSCs was analyzed. In addition, after 3 months, we followed up 40 patients with lung cancer, recorded their prognosis, and extracted peripheral blood to detect changes in their CTCs and CSCs. The CellSearch (Huntington Valley, PA, USA) system and the microfluidic chip system were used to detect the CTCs in patients with lung cancer, and the sensitivity and specificity of the patients were analyzed. The changes in CTCs and CSCs in the peripheral blood of the patient were recorded. RESULTS: It can be seen that the positive rate of CTCs and CSCs is not significantly correlated with the patients' age, gender, pathological type (adenocarcinoma, squamous cell carcinoma), etc. They are significantly correlated with clinical stage (I + II and III + IV) and metastasis (metastasis and non-metastasis) (p<0.01). Then, we divided the patients into groups for testing, and analyzed the association between different groups of patients and CTCs and CSCs. Compared with control group 1 and control group 2, the positive rates of CTCs and CSCs in lung cancer metastasis group and non-metastasis group were significantly different (p<0.05). Compared with the control group 1 and control group 2, the positive rates of CTCs and CSCs in stage I + II and III + IV of lung cancer were significantly different (p<0.05). The positive rate was significantly higher in the cancer metastasis group (p<0.05). The concentrations of tumor markers VEGF-C, CEA, CA125 in the serum of patients were consistent with CTCs-negative and CTC-positive lung cancer, with significant differences (p<0.05). CSCs negative and CSCs positive patients have similar results. Subsequently, we analyzed the sensitivity and specificity of CSCs, CTCs, and tumor markers for the diagnosis of NSCLC. The results showed that the sensitivity of CSCs and CTCs to diagnose patients was significantly higher than that of tumor markers. CONCLUSIONS: This study shows that our microfluidic chip device can exhibit relatively good performance and can better detect CTCs and CSCs. Monitoring CTCs and CSCs of patients can provide a basis for judging the stage and metastasis of patients.

[The clinical significance of circulating follicular helper T cells in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis].

Objective: To investigate the change of circulating follicular helper T cells (cTfh) in patients with anti-neutrophil cytoplasmic myeloperoxidase antibody-associated vasculitis (MPO-AAV), and to analyze the relationship between cTfh and disease activity. Methods: Thirty-eight untreated MPO-AAV patients (patient group) and thirty-eight healthy volunteers (control group) were enrolled in this study. cTfh and membrane expression of inducible co-stimulator (ICOS) and programmed cell death protein 1 (PD-1) were detected by flow cytometry (FCM). Serum anti-neutrophil cytoplasmic myeloperoxidase antibody (MPO-ANCA) was measured by ELISA. Disease activity was evaluated by Birmingham vasculitis activity score (BVAS). Results: Compared with those in control group, the proportions of cTfh, ICOS(+)Tfh and PD-1(+) Tfh cells in patient group were significantly higher [(25.9±3.8)% vs. (21.0±5.3)%, P<0.001; (1.8±0.8)% vs. (0.8±0.5)%, P<0.001 and (10.2±2.8)% vs. (8.2±2.2)%, P=0.001, respectively]. Meanwhile, the expression of ICOS and PD-1 on cTfh in patient group was markedly more intensive (59.6±10.0 vs.49.2±6.9, P<0.001 and 532.6±104.2 vs. 485.1±73.4, P=0.025, respectively). In patient group, the proportion of cTfh was positively correlated with the ratio of ICOS(+)Tfh, the expression of ICOS, the level of MPO-ANCA and BVAS (r=0.407, P=0.011; r=0.705, P<0.001; r=0.737, P<0.001 and r=0.663, P<0.001, respectively). The expression intensity of ICOS on cTfh was positively associated with ICOS(+)Tfh ratio, serum MPO-ANCA and BVAS (r=0.388, P=0.016; r=0.645, P<0.001 and r=0.653, P<0.001, respectively). Nevertheless, the expression of PD-1 on cTfh was only positively correlated with the ratio of PD-1(+) Tfh (r=0.473, P=0.003). Conclusions: Enhanced cTfh in patients with MPO-AAV might produce MPO-ANCA, which is related to the aggravation of MPO-AAV. Thus, cTfh and its ICOS could be potentially targeted for the treatment of MPO-AAV.

[The significances of peripheral neutrophils CD(55) and myeloperoxidase expression in patients with myeloperoxidase-specific anti-neutrophil cytoplasmic antibody associated vasculitis].

Objective: To investigate the expression of CD(55) and myeloperoxidase (MPO) on neutrophils in patients with MPO-specific anti-neutrophil cytoplasmic antibody associated vasculitis(MPO-AAV), and analyze the relationship between the expression and clinical manifestation. Methods: Forty untreated patients with active MPO-AAV (patient group) and 30 healthy volunteers (control group) were enrolled in this study. The CD(55) on neutrophils and both membrane and cytoplasmic MPO were detected by flow cytometry. Serum fragment-from the activated complement factor B(Ba) and MPO were measured by ELISA. The clinical activity of vasculitis was valued by Birmingham vasculitis activity score-version 3(BVAS-V3). The significance of laboratory data was evaluated by Spearman correlation test and multivariate linear regression analysis. Results: (1)The mean fluorescence intensity(MFI) of CD(55) expressed on neutrophils was significantly higher than that in control group[4 068.6±2 306.0 vs 2 999.5±1 504.9, P=0.033]. Similar results of serum MPO and Ba in patient group were found compared to controls [500.0(381.0, 612.7) IU/L vs 286.9(225.5, 329.1) IU/L, P<0.001; 35.2(25.2, 79.5) ng/L vs 18.0(15.0, 28.0) ng/L, P<0.001], respectively. However, MIF of cytoplasmic MPO in patients was significantly lower than that of control group(1 577.1±1 175.9 vs 3 105.3±2 323.0, P=0.003) . (2) In patient group, cytoplasmic intensity of MPO was negatively associated with the serum levels of MPO(r=-0.710, P<0.001) and Ba (r=-0.589, P=0.001). Moreover, serum MPO was positively associated with serum Ba(r=0.691, P<0.001). Membrane intensity of CD(55) on neutrophils was positively correlated with patient age (r=0.514, P=0.001), C reactive protein (r=0.376, P=0.018), peripheral neutrophils count (r=0.485, P=0.001) and BVAS-V3 (r=0.484, P=0.002), whereas negative correlation between membrane CD(55) and disease duration was seen (r=-0.403, P=0.01). (3) The result of multiple linear regression analysis showed there was statistically significant positive correlation between MFI of CD(55) expressed on neutrophils and BVAS-V3 (ß=0.001, P=0.027). Conclusions: In MPO-AAV, CD(55) expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity. It might protect neutrophils from attacking AAV, CD(55) expression on neutrophils is markedly enhanced, which is one of the independent risk factors related to disease activity. It might protect neutrophils from attacking by complement alternative pathway. Activated neutrophils release more MPO and lysosome to intensify the inflammation reaction and aggravate the disease. Thus CD(55) might become a new potential target for the treatment of this disease in the future.

Autophagy-related IRGM genes confer susceptibility to ankylosing spondylitis in a Chinese female population: a case-control study.

It is known that ankylosing spondylitis (AS) and inflammatory bowel disease (IBD) shared a common genetic component. The gist of current study is to assess the role of IBD-associated autophagy gene IRGM on AS susceptibility in a Chinese Han population. A total of 1270 unrelated subjects (643 AS and 627 controls) were enrolled. Two tag single-nucleotide polymorphisms (SNPs) (rs10065172 and rs4958846) were selected and were genotyped by iMLDR Assay technology. Genotypes and haplotype analysis were conducted by using SPSS 16.0 and haploview 4.2 software. Among two tag SNPs of IRGM, no correlation was observed between rs10065172 and AS susceptibility. For rs4958846, genotype and allelic frequencies were marginally discrepant between female cases and controls before, not after, Bonferroni correction (P=0.049; P=0.031). Logistic regression analysis revealed that carriers with CT+TT or CT genotype had a significantly decreased risk for developing AS among female subjects when compared with CC genotype (OR=0.514, 95% CI=0.301-0.876, P=0.014; OR=0.518, 95% CI=0.297-0.902, P=0.020, respectively). Additionally, a risk haplotype rs4958846C-rs10065172C (OR=2.093, 95% CI=1.301-3.368) and a protective haplotype rs4958846T-rs10065172C (OR=0.652, 95% CI=0.441-0.964) were also identified to be associated with female AS. IBD-associated IRGM gene is also associated with AS susceptibility in the Chinese female population, indicating that autophagy pathway may involve in AS genetic predisposition.

Role of autoantibodies to various Ro60 epitopes in the decrease of lymphocytes seen in systemic lupus erythematosus and primary Sjögren's syndrome.

We investigated the roles of autoantibodies to different Ro60 epitopes in lymphopenia in systemic lupus erythematosus (SLE) and primary Sjögren's syndrome (pSS). We recruited 16 patients with SLE, 14 with pSS, and 10 healthy controls; all were female. Patients had active disease, had not received glucocorticoid or immunosuppressants for at least 3 months, and had positive laboratory tests for autoantibodies against Ro60. Patient peripheral blood lymphocyte (LC) counts were < 1 x 10(9)/L: (0.66 ± 0.12) x 10(9)/L and (0.70 ± 0.16) x 10(9)/L for SLE and pSS groups, respectively (P = 0.511). LCs from each group were cultured in vitro with each of the three immunotoxins (ITs) (AE1-3), which specifically combine with one of the three epitopes (aa482-493, aa310-323, and aa230-241, respectively) on Ro60. The cytotoxicity of each IT to the cultured LCs was measured by the MTT colorimetric method. The relationships between IT cytotoxicity and LC counts were analyzed, and autoantibodies against the three epitopes in patient peripheral blood were detected. All ITs showed cytotoxicity to control LCs; however, AE3 and AE2 showed greater toxicity to LCs from SLE and pSS groups, respectively, and the enhanced cytotoxicity was significantly associated with the respective LC counts (r = 0.653, P = 0.06; r = 0.594, P = 0.025). No difference was found in the prevalence of the autoantibodies between the SLE and pSS groups. These results suggest that autoantibodies to Ro60 might play a pathogenic role in lymphopenia in both SLE and pSS, but the pathogenic mechanisms might differ.

Clinical analysis of patients with myeloperoxidase antineutrophil cytoplasmic antibody-associated vasculitis.

This prospective study analyzed the clinical characteristics of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis and explored the relationship between MPO-ANCA and clinical manifestations of the associated vasculitis in 132 p-ANCA and MPO-ANCA-positive patients (average age, 62.3 ± 14.8 years) who were initially diagnosed with ANCA-associated vasculitis. The p-ANCA and MPO-ANCA levels in peripheral blood were detected in all patients. Among these, 128 (97%) had microscopic polyangiitis (MPA), 3 (2.3%) had granulomatous polyangiitis, and 1 (0.7%) had eosinophilic granulomatous vasculitis. The average time of diagnosis was 10.2 ± 18 months; only 14 (10.6%) patients were diagnosed within 1 month. The main organs involved and the corresponding number of patients were: renal, 95 (72%); lung, 89 (67.4%); joints, 35 (26.5%); heart, 26 (19.7%); peripheral nerve, 23 (17.4%); skin rash, 14 (10.6%); and CNS, 13 (9.8%). Older patients were more likely to show lung involvement in the early disease stage, whereas the joints were involved mostly in the younger patients. The p-ANCA levels (mean titers, 1:60) were not correlated with disease activity and extent of organ involvement, and the MPO-ANCA levels were positively correlated with disease activity, but had no correlation with the extent of organ involvement. MPO-ANCA vasculitis is a common occurrence in China; it mainly involves the elderly and presents as clinical manifestations of MPA. However, the multiple organ damage is not specific leading to delay in diagnosis. MPO-ANCA may play a pathogenic role in the associated vasculitis, and the diverse clinical manifestations might be related with the different characteristics of MPO-ANCA.

Effects of pressure and temperature on the carrier transports in organic crystal: a first-principles study.

By employing density-functional theory coupled with Holstein-Peierls model, we investigate the pressure and temperature dependence of the hole and electron mobilities in naphthalene single crystal from atmospheric pressure up to 2.1 GPa (at room temperature) and from 5 to 296 K (at ambient pressure). It is found that the pressure reduces the electron-phonon coupling strength and enhances the mobilities. Importantly, we point out that only when temperature-dependent structure modifications are taken into account can one better describe the temperature-dependent transport behavior. Especially, the band to hopping crossover transition temperature for the electron transport in the c'-axis is calculated to be around 153 K, which is close to the experimental result of between 100 and 150 K. If this temperature-dependent structure modifications were neglected, the transition temperature would be only about 23 K, as previously obtained [L. J. Wang et al., J. Chem. Phys. 127, 044506 (2007)].

Roles of inter- and intramolecular vibrations and band-hopping crossover in the charge transport in naphthalene crystal.

We calculate the hole and electron mobilities in naphthalene crystal from 10 to 300 K within the framework of the Holstein-Peierls model coupled with first-principles density-functional-theory-projected tight-binding band structures. All the electron-phonon coupling constants, including both local and nonlocal parts for inter- and intramolecular vibrations, have been taken into considerations through density functional theory. The band-hopping crossover transition temperature for the electron transport in the c' axis is calculated to be around 23 K. We have identified a few high frequency intramolecular vibrations which are very important to the charge transport in naphthalene crystal due to their comparatively large electron-phonon coupling constants. However, their contributions to the temperature dependence of mobility are minor because of the small phonon occupations and small nonlocal coupling strengths. The low frequency intermolecular modes (longitudinal optical modes) are found to be the major contributions to the temperature dependent charge transfer properties in naphthalene crystal. Even though the calculated qualitative temperature dependence is in agreement with experiment, the predicted absolute mobility is about one to two orders of magnitude larger.

Inelastic x-ray scattering study of exciton properties in an organic molecular crystal.

Excitons in a complex organic molecular crystal were studied by inelastic x-ray scattering (IXS) for the first time. The dynamic dielectric response function is measured over a large momentum transfer region, from which an exciton dispersion of 130 meV is observed. Semiempirical quantum chemical calculations reproduce well the momentum dependence of the measured dynamic dielectric responses, and thus unambiguously indicate that the lowest Frenkel exciton is confined within a fraction of the complex molecule. Our results demonstrate that IXS is a powerful tool for studying excitons in complex organic molecular systems. Besides the energy position, the IXS spectra provide a stringent test on the validity of the theoretically calculated exciton wave functions.

Electron transport in self-assembled polymer molecular junctions.

A molecular junction of a poly(p-phenyleneethynylene)s derivative with thioacetate end groups (TA-PPE) was fabricated by self-assembling. Nanogap electrodes made by electroplating technique was used to couple thiol end groups of TA-PPE molecules. Room temperature current-voltage characteristics of the molecular junction exhibited highly periodic, repeatable, and identical stepwise features. First-principles calculations suggest that one possibility for the equidistant step is due to the opening of different conducting channels that corresponds to the unoccupied molecular orbitals of the polymer in the junction. It is interesting to see that an 18 nm long polymer is of quantized electronic structures and behaves like a quantum transport device.

Optical properties of singly charged conjugated oligomers: a coupled-cluster equation of motion study.

We have implemented a coupled-cluster equation of motion approach combined with the intermediate neglect of differential overlap parametrization and applied it to study the excited states and optical absorptions in positively and negatively charged conjugated oligomers. The method is found to be both reliable and efficient. The theoretical results are in very good agreement with experiments and confirm that there appear two subgap absorption peaks upon polaron formation. Interestingly, the relative intensities of the polaron-induced subgap absorptions can be related to the extent of the lattice geometry relaxations.

Singlet-triplet splitting of geminate electron-hole pairs in conjugated polymers.

The singlet-triplet splitting of geminate polaron pairs in a ladder-type conjugated polymer has been studied by the thermally stimulated luminescence technique. The energy gap separating the singlet and triplet states of the geminate pairs is measured to be in the range of 3-6 meV, depending on the polymer morphology. The results of correlated quantum-chemical calculations on a long ladder-type oligomer are fully consistent with the observed values of the geminate polaron pair singlet-triplet gap. Such low splitting values have important implications for the spin-dependent exciton formation in conjugated polymers.