Common carotid artery diameter and the risk of cardiovascular disease mortality: a prospective cohort study in northeast China

BACKGROUND

The association between the common carotid artery (CCA) diameter and cardiovascular disease (CVD) is recognized, but the precise nature of this link remains elusive. This study aimed to investigate the potential relationship between CCA diameter and the risk of CVD mortality in a large population in northeast China.

METHODS

The current study included 5668 participants (mean age 58.9 ± 10.1 years) from a population-based study conducted in rural areas of northeast China between September 2017 and May 2018. Information on death was collected from baseline until July 31, 2022. The CCA inter-adventitial diameter was measured using ultrasound. Cox proportional-hazard models were employed to explore the relationship between the common carotid artery diameter and cardiovascular mortality.

RESULTS

At baseline, the mean CCA diameter (mm) of subjects was 7.30 ± 0.99 and increased significantly with age, ranging from 6.65 ± 0.71 among people 40-49 years to 7.99 ± 1.04 among people ≥ 80 years. CCA diameter was significantly larger in males compared to females (7.51 ± 1.03 versus vs. 7.16 ± 0.94; P < 0.001). A total of 185 participants died of CVD during a median follow-up of 4.48 years. CCA diameters were divided into quartiles, and the highest quartile of carotid diameter (≥ 8.06 mm) had a 2.29 (95% confidence interval [CI]: 1.24, 4.22) times higher risk of CVD mortality than the lowest quartile (≤ 6.65 mm) (P < 0.01) in the fully adjusted model. Each increase in the diameter of the common carotid artery (per SD) raised the risk of cardiovascular death by 36% (hazard ratio [HR]: 1.36; 95% CI: 1.18, 1.57). The subgroup analysis results demonstrated that a per SD increase was associated with a 42% increased risk of CVD mortality in participants aged ≥ 64 years in the fully adjusted model (HR: 1.42; 95%CI: 1.21, 1.66).

CONCLUSIONS

Our study indicates the possible incremental value of CCA diameter in optimizing the risk stratification of cardiovascular disease and provides essential insights into reducing the burden of cardiovascular disease.

Insight into the Inhibitory Mechanism of Embryonic Ectoderm Development Subunit by Triazolopyrimidine Derivatives as Inhibitors through Molecular Dynamics Simulation

Inhibition of the Embryonic Ectoderm Development (EED) subunit in Polycomb Repressive Complex 2 (PRC2) can inhibit tumor growth. In this paper, we selected six experimentally designed EED competitive Inhibitors of the triazolopyrimidine derivatives class. We investigated the difference in the binding mode of the natural substrate to the Inhibitors and the effects of differences in the parent nuclei, heads, and tails of the Inhibitors on the inhibitory capacity. The results showed that the binding free energy of this class of Inhibitors was close to or lower compared to the natural substrate, providing an energetic basis for competitive inhibition. For the Inhibitors, the presence of a strong negatively charged group at the 6-position of the parent nucleus or the 8'-position of the head would make the hydrogen atom on the head imino group prone to flip, resulting in the vertical movement of the parent nucleus, which significantly decreased the inhibitory ability. When the 6-position of the parent nucleus was a nonpolar group, the parent nucleus would move horizontally, slightly decreasing the inhibitory ability. When the 8'-position of the head was methylene, it formed an intramolecular hydrophobic interaction with the benzene ring on the tail, resulting in a significant increase in inhibition ability.

Receptor modulators associated with the hypothalamus -pituitary-thyroid axis

The hypothalamus-pituitary-thyroid (HPT) axis maintains normal metabolic balance and homeostasis in the human body through positive and negative feedback regulation. Its main regulatory mode is the secretion of thyrotropin (TSH), thyroid hormones (TH), and thyrotropin-releasing hormone (TRH). By binding to their corresponding receptors, they are involved in the development and progression of several systemic diseases, including digestive, cardiovascular, and central nervous system diseases. The HPT axis-related receptors include thyrotropin receptor (TSHR), thyroid hormone receptor (TR), and thyrotropin-releasing hormone receptor (TRHR). Recently, research on regulators has become popular in the field of biology. Several HPT axis-related receptor modulators have been used for clinical treatment. This study reviews the developments and recent findings on HPT axis-related receptor modulators. This will provide a theoretical basis for the development and utilisation of new modulators of the HPT axis receptors.

Induction Immunotherapy vs. Consolidation Immunotherapy for Unresectable Stage III NSCLC

PURPOSE/OBJECTIVE(S)

Consolidation immunotherapy after chemoradiotherapy (CRT) is the standard of care for unresectable stage III non-small cell lung cancer (NSCLC). However, whether upfront immunotherapy before CRT has similar benefits has not been addressed. This study aimed at exploring the efficacy and safety of induction immunotherapy for unresectable stage III NSCLC through real-world data.

MATERIALS/METHODS

Patients diagnosed with stage III NSCLC who received immunotherapy in combination with sequential (sCRT) or concurrent CRT (cCRT) between November 2018 and December 2021 were retrospectively identified. Patients were divided into induction (Ind), consolidation (Con) and induction plus consolidation (Ind+Con) immunotherapy groups. Progression-free survival (PFS) and overall survival (OS) were assessed from the initiation of treatment and estimated by Kaplan‒Meier method. The potential factors affecting PFS and OS were analyzed by univariate and multivariate Cox regression models.

RESULTS

One hundred and two patients were included, with 52 (51.0%) patients in the Ind group, 35 (34.3%) in the Con group and 15 (14.7%) in the Ind+Con group. Median PFS was 24.0 months vs. 36.0 months vs. 19.0 months in the three groups, and 2-year PFS were 43.0% vs 51.1% vs 44.4% (p = 0.940). Median OS was not reached (NR) vs. 44.0 months vs. NR, with a 2-year OS rate of 80.5% vs. 84.4% vs. 86.2% (p = 0.861). In the cCRT setting, 2-year PFS rates were 56.7% vs. 71.6% vs. 100.0% (p = 0.439), 2-year OS rates were 92.3% vs. 89.3% vs. 100.0% in the three groups (p = 0.827). In multivariate analysis, elder (HR = 0.487, p = 0.037) and cCRT (HR = 0.282, p = 0.001) were the independent factors favoring PFS, while only elder (HR = 0.088, p = 0.021) was the independent factors favoring OS. Adverse events were similar in the three arms. Further analysis found the objective response rate (ORR) and disease control rate (DCR) in the Ind and Ind+Con group after induction immunotherapy were 59.7% and 98.5%, respectively. Only 1 (1.5%) patient developed progression. Subgroup analysis showed no significant difference in PFS (p = 0.520) and OS (p = 0.116) between patients who responded to induction immunotherapy (PR+CR) and those who did not (SD+PD). Patients with <4 cycles of induction immunotherapy exhibited numerically better PFS than those with ≥4 cycles of induction immunotherapy (p = 0.113) and improved OS (p = 0.021).

CONCLUSION

Induction immunotherapy may achieve similar survival benefits to consolidation immunotherapy, and the combination of induction and consolidation immunotherapy with cCRT appears to achieve better outcomes. It seems feasible and safe to upfront immunotherapy before CRT, and further investigations on the combination of induction immunotherapy and CRT are warranted.

Solvent-controlled formation of alkali and alkali-earth-secured cucurbituril/guest trimers

Cucurbit[7]uril (CB[7]) encapsulates adamantyl and trimethylsilyl substituents of positively charged guests in dimethyl sulfoxide (DMSO). Unlike in water or deuterium oxide, addition of a selection of alkali and alkali-earth cations with van der Waals radii between 1.0 and 1.4 Å (Na+, K+, Ca2+, Sr2+, Ba2+ and Eu3+) to the CB[7]/guest complexes triggers their cation-mediated trimerization, a process that is very slow on the nuclear magnetic resonance (NMR) time scale. Smaller (Li+, Mg2+) or larger cations (Rb+, Cs+ or NH4+) are inert. The trimers display extensive CH-O interactions between the equatorial and pseudo-equatorial hydrogens of CB[7] and the carbonyl rim of the neighboring CB[7] unit in the trimer, and a deeply nested cation between the three interacting carbonylated CB[7] rims; a counteranion is likely perched in the shallow cavity formed by the three outer walls of CB[7] in the trimer. Remarkably, a guest must occupy the cavity of CB[7] for trimerization to take place. Using a combination of semi-empirical and density functional theory techniques in conjunction with continuum solvation models, we showed that trimerization is favored in DMSO, and not in water, because the penalty for the partial desolvation of three of the six CB[7] portals upon aggregation into a trimer is less unfavorable in DMSO compared to water.

[STIP1 correlates with tumor immune infiltration and prognosis as a potential immunotherapy target: a pan-cancer bioinformatics analysis]

OBJECTIVE

To investigate the correlation of stress-inducible phosphoprotein 1 (STIP1) expression level with prognosis of different cancers and its potential role in immunotherapy.

METHODS

TCGA, TARGET and GTEx databases were used for bioinformatic analysis of STIP1 expression level and its prognostic value in different cancers. We also detected STIP1 expression immunohistochemically in 10 pairs of colorectal cancer and adjacent tissues. We further analyzed the correlation of STIP1 expression level with tumor mutational burden, microsatellite instability, immune cell infiltration, immune regulators and outcomes of different cancers. STIP1- related proteins were identified using protein- protein interaction (PPI) network analysis, and functional enrichment analysis was performed to analyze the regulatory pathways involving STIP1.

RESULTS

Bioinformatics analysis showed that STIP1 was highly expressed in most tumors compared with the normal tissues (P < 0.05), which was confirmed by immunohistochemistry of the 10 pairs of colorectal cancer tissues. STIP1 expression level was correlated with clinical stages of multiple cancers (P < 0.05), and in some cancer types, an upregulated STIP1 expression was correlated with a poor prognosis of the patients in terms of overall survival, disease-specific survival, disease-free survival and progression-free survival (P < 0.05). STIP1 expression was significantly correlated with tumor mutational burden, microsatellite instability, immune cell infiltration and immunomodulatory factors in most tumors (P < 0.05). PPI network analysis indicated that STIP1-related proteins included HSPA4, HSPA8, and HSP90AA1. KEGG enrichment analysis suggested that the high expression of STIP1 in liver cancer was related mainly with valerate metabolism, tryptophan metabolism, and butyrate metabolism pathways; HALLMARK enrichment analysis suggested high STIP1 expression in liver cancer was involved in bile acid and fatty acid metabolism.

CONCLUSION

STIP1 is up-regulated in multiple cancer types and its expression level is correlated with clinical tumor stage, tumor mutational burden, microsatellite instability, immune cell infiltration and immunomodulatory factors.

Mechanism Exploration of Amyloid-β-42 Disaggregation by Single-Chain Variable Fragments of Alzheimer's Disease Therapeutic Antibodies

Alzheimer's disease (AD) is a specific neurodegenerative disease. This study adopts single-chain variable fragments (scFvs) as a potential immunotherapeutic precursor for AD. According to the remarkable effects of monoclonal antibodies, such as the depolymerization or promotion of Aβ42 efflux by Crenezumab, Solanezumab, and 12B4, it is attractive to prepare corresponding scFvs targeting amyloid-β-42 protein (Aβ42) and investigate their biological activities. Crenezumab-like scFv (scFv-C), Solanezumab-like scFv (scFv-S), and 12B4-like scFv (scFv-12B4) were designed and constructed. The thermal stabilities and binding ability to Aβ42 of scFv-C, scFv-S, and scFv-12B4 were evaluated using unfolding profile and enzyme-linked immunosorbent assay. As the results indicated that scFv-C could recognize Aβ42 monomer/oligomer and promote the disaggregation of Aβ42 fiber as determined by the Thioflavin-T assay, the potential mechanism of its interaction with Aβ42 was investigated using molecular dynamics analysis. Interactions involving hydrogen bonds and salt bonds were predicted between scFv-C and Aβ42 pentamer, suggesting the possibility of inhibiting further aggregation of Aβ42. The successfully prepared scFvs, especially scFv-C, with favorable biological activity targeting Aβ42, might be developed for a potentially efficacious clinical application for AD.

[Application of short-course radiotherapy with total neoadjuvant therapy in the treatment of middle and low rectal cancer]

Objective: To compare the efficacy and safety of short-course radiotherapy with total neoadjuvant therapy (SCRT-TNT) and neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced middle and low rectal cancer. Methods: A retrospective cohort study was carried out. A of 126 patients with locally advanced middle and low rectal cancer who were treated in the Department of Gastrointestinal Cancer Surgery of Fujian Cancer Hospital from September 2016 to March 2020 were enrolled, including 73 males and 53 females, with a mean age of (56.5±9.8) (23-77) years. Based on neoadjuvant regimen (nCRT treatment was performed before December 2018 and SCRT-TNT treatment was carried out after January 2019), patients were divided into nCRT group (n=68) and SCRT-TNT group (n=58). There were no statistically significant differences in age, sex, distance from tumor to anal verge, Eastern Cooperative Oncology Group (ECOG) performance status and clinical TNM stage between the two groups (all P>0.05). Patients in both groups received pelvic intensity-modulated radiotherapy (IMRT). The radiotherapy dose of nCRT group was 50Gy/25 times/5 weeks. Patients in nCRT group received oral capecitabine chemotherapy during radiotherapy and underwent surgery 6-8 weeks after chemoradiation. However, patients in SCRT-TNT group received CapeOX regimen (oxaliplatin+capecitabine) for 2 cycles of induction chemotherapy, followed by short-course radiotherapy (25Gy/5 times/5 days), then underwent a radical surgery two weeks after completion of consolidation chemotherapy (4 cycles). The adverse reactions, perioperative safety and efficacy of neoadjuvant therapy were compared and analyzed between the two groups. Results: Both groups completed neoadjuvant therapy as planned. Patients in nCRT group and SCRT-TNT group had similar incidence of adverse reactions to radiotherapy and chemotherapy, however, there were no statistically significant differences in the incidence of surgical complications, operation time, intraoperative blood loss and postoperative length of hospital stay (all P>0.05). A total of 119 patients underwent total mesenterectomy (TME), including 64 patients in the nCRT group and 55 patients in the SCRT-TNT group, all with R0 resection. The pathological complete response (pCR) rate was 10.9% (7/64) in the nCRT group and 25.5% (14/55) in the SCRT-TNT group, respectively, with a statistically significant difference (P=0.038). Two years after surgery, there was no statistically significant difference in local recurrence rate and overall survival rate between the two groups (both P>0.05). However, the clinical metastasis rate of SCRT-TNT group was significantly lower than that of nCRT group (20.3% vs 9.1%), with a statistically significant difference (P<0. 05). Conclusion: SCRT-TNT do not increase the adverse reactions of radio chemotherapy and perioperative risks in the treatment of locally advanced middle and low rectal cancer, and the tumor regression effect is good, which is worthy of clinical promotion.

Protonated α-N-Acetyl Galactose Glycopeptide Dissociation Chemistry

We recently provided mass spectrometric, H/D labeling, and computational evidence of pyranose to furanose N-acetylated ion isomerization reactions that occurred prior to glycosidic bond cleavage in both O- and N-linked glycosylated amino acid model systems (Guan et al. Phys. Chem. Chem. Phys., 2021, 23, 23256-23266). These reactions occurred irrespective of the glycosidic linkage stereochemistry (α or β) and the N-acetylated hexose structure (GlcNAc or GalNAc). In the present article, we test the generality of the preceding findings by examining threonyl α-GalNAc-glycosylated peptides. We utilize computational chemistry to compare the various dissociation and isomerization pathways accessible with collisional activation. We then interrogate the structure(s) of the resulting charged glycan and peptide fragments with infrared "action" spectroscopy. Isomerization of the original pyranose, the protonated glycopeptide [AT(GalNAc)A+H]⁺, is predicted to be facile compared to direct dissociation, as is the glycosidic bond cleavage of the newly formed furanose form, i.e., furanose oxazolinium ion structures are predicted to predominate. IR action spectra for the m/z 204, C₈H₁₄N₁O₅⁺, glycan fragment population support this prediction. The IR action spectra of the complementary m/z 262 peptide fragment were assigned as a mixture of the lowest-energy structures of [ATA+H]⁺ consistent with the literature. If general, the change to a furanose m/z 204 product ion structure fundamentally alters the ion population available for MS³ dissociation and glycopeptide sequence identification.

[Surgical management of nipple areola complex in central breast cancer]

Objective: To explore the surgical strategy of nipple areola complex (NAC) management in central breast cancer. Methods: A retrospective analysis was conducted on 164 cases of central breast cancer who underwent surgery treatment from December 2017 to December 2020 in the Breast Center of Beijing Tongren Hospital, Capital Medical University. Prior to the surgery, the tumor-nipple distance (TND) and the maximum diameter of the tumor were measured by magnetic resonance imaging (MRI). The presence of nipple invagination, nipple discharge, and nipple ulceration (including nipple Paget's disease) were recorded accordingly. NAC was preserved in patients with TND≥0.5 cm, no signs of NAC invasion (nipple invagination, nipple ulceration) and negative intraoperative frozen pathological margin. All patients with signs of NAC involvement, TND<0.5 cm or positive NAC basal resection margin confirmed by intraoperative frozen pathology underwent NAC removal. χ(2) test or Fisher exact test was used to analyze the influencing factors. Results: Of the 164 cases of central breast cancer, 73 cases underwent breast-conserving surgery, 43 cases underwent nipple-areola complex sparing mastectomy (NSM), 34 cases underwent total mastectomy, and the remaining 14 cases underwent skin sparing mastectomy (SSM). Among the 58 cases of NAC resection (including 34 cases of total mastectomy, 14 cases of SSM, and 10 cases of breast-conserving surgery), 25 cases were confirmed tumor involving NAC (total mastectomy in 12 cases, SSM in 9 cases, and breast-conserving surgery in 4 cases). The related factors of NAC involvement included TND (P=0.040) and nipple invagination (P=0.031). There were no correlations between tumor size (P=0.519), lymph node metastasis (P=0.847), bloody nipple discharge (P=0.742) and NAC involvement. During the follow-up period of 12 to 48 months, there was 1 case of local recurrence and 3 cases of distant metastasis. Conclusions: For central breast cancer, data suggest that patients with TND≥0.5cm, no signs of NAC invasion (nipple invagination, nipple ulceration) and negative NAC margin in intraoperative frozen pathology should be treated with NAC preservation surgery, whereas for those with TND<0.5 cm or accompanied by signs of NAC invasion, NAC should be removed. In addition, nipple reconstruction can be selected to further improve the postoperative appearance of patients with central breast cancer.

Treatment-related adverse events as predictive biomarkers of efficacy in patients with advanced neuroendocrine tumors treated with surufatinib: results from two phase III studies

Background

No validated biomarkers currently exist for predicting the efficacy outcomes in patients with neuroendocrine tumors (NETs) treated with antiangiogenic therapy. We aimed to evaluate the association between treatment-related adverse events (TRAEs) and efficacy outcomes of surufatinib in patients with advanced NET.

Patients and methods

We included patients with NET treated with surufatinib in two multicenter, randomized, double-blind, placebo-controlled, phase III trials (SANET-p and SANET-ep) in this study. The main exposure was the presence of any of the TRAEs including hypertension, proteinuria, and hemorrhage in the first 4 weeks of surufatinib treatment. The primary outcome of the study was investigator-assessed progression-free survival (PFS). PFS outcomes were estimated using the Kaplan–Meier method with the log-rank test. Hazard ratios (HRs) were calculated by using univariable and multivariable Cox proportional hazard regression models. Blinded independent image review committee (BIIRC) assessments and 4-week landmark analysis were also performed as supportive evaluations.

Results

During the study period, a total of 242 patients treated with surufatinib were included in the analysis, and 164 (68%) patients had at least one of hypertension, proteinuria, and hemorrhage in the first 4 weeks of treatment. The presence of TRAEs in the first 4 weeks was associated with prolonged median PFS [11.1 versus 9.2 months; HR 0.67, 95% confidence interval (CI) 0.47-0.97; P = 0.036]. In multivariable Cox regression analysis, the presence of TRAEs was also significantly associated with longer PFS (HR 0.65, 95% CI 0.44-0.97; P = 0.035). Similar results were obtained in the BIIRC assessments and 4-week landmark analysis.

Conclusions

Treatment-related hypertension, proteinuria, and hemorrhage could be potential biomarkers to predict antitumor efficacy of surufatinib in patients with advanced NET. Future prospective studies are needed to validate the findings.

Trial registration

ClinicalTrials.govNCT02589821; https://clinicaltrials.gov/ct2/show/NCT02589821 and ClinicalTrials.gov NCT02588170; https://clinicaltrials.gov/ct2/show/NCT02588170

•

Treatment-related hypertension, proteinuria, or hemorrhage is associated with longer survival in NETs.

•

The association is confirmed by the BIIRC assessments and 4-week landmark analysis.

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TRAEs can be biomarkers to predict antitumor efficacy in patients with NET.

[Incision selection for nipple-sparing mastectomy with implant-based breast reconstruction]

Objective: To examine the outcome of different incision selection for nipple-sparing mastectomy (NSM) with implant-based breast reconstruction (IBBR). Methods: Ninety-Two cases accepted NSM and IBBR from totally 1 002 cases of breast cancer admitted to Beijing Tongren Hospital Affiliated to Capital Medical University from June 2013 to December 2020 were analyzed retrospectively. All the patients were female, aging (42.0±7.5) years (range: 27 to 64 years). There were 12 patients at stage 0, 47 patients at stage Ⅰ, 17 patients at stage Ⅱ, and 16 patients at stage Ⅲ. The patients were divided in three groups by the incision: peri-areolar group (n=23), inframammary group (n=33) and lateral group (n=36). The age, tumor size, lymph node status, hormone receptor, operation method and postoperative complications were followed-up of three groups and compared by one-way ANOVA, χ² test or Fisher's exact test and expansion to comparied. Results: There was no significant difference in operation time ((180.7±54.0) minutes vs. (176.9±48.1) minutes vs. (194.6±37.5) minutes, F=1.401, P=0.252), postoperative drainage volume ((497.5±226.0) ml vs. (495.4±182.5) ml vs. (519.8±172.0) ml, F=0.167, P=0.846) and drainage time ((8.8±3.8) days vs. (8.0±2.5) days vs. (8.3±2.9) days, F=0.542, P=0.583) among the peri-areolar, inframammary, and lateral groups. The cumulative postoperative complications were relatively higher in the peri-areola group (26.1%(6/23) vs. 0 vs.8.3%(3/36), χ²=9.675, P=0.004). All female patients were followed up for (49.0±25.6) months(range: 12 to 112 months). Breast cancer related death rate was 2.2% (2/92), local recurrence was 1.1% (1/92), regional recurrence was 4.3% (4/92), distant metastasis was 6.5% (6/92), and the disease-free survival rate was 88.0% (81/92). Conclusion: The surgical effects of the peri-areolar, inframammary and lateral incisions for NSM and IBBR are approximate, the total complication rate of the peri-areolar incision is slightly higher.

Hemagglutinin-based DNA vaccines containing trimeric self-assembling nanoparticles confer protection against influenza

Influenza viruses continue to threaten public health, and currently available vaccines provide insufficient immunity against seasonal and pandemic influenza. The use of recombinant trimeric hemagglutinin (HA) as an Ag provides an attractive alternative to current influenza vaccines. Aiming to develop an effective vaccine with rapid production, robust immunogenicity, and high protective efficiency, a DNA vaccine was designed by fusing influenza virus HA with self-assembled ferritin nanoparticles, denoted as HA-F. This candidate vaccine was prepared and purified in a 293-6E cell eukaryotic expression system. After BALB/c mice were immunized with 100 μg of HA-F DNA 3 times, HA-F elicited significant HA-specific humoral immunity and T cell immune responses. The HA-F DNA vaccine also conferred protection in mice against a lethal infection of homologous A/17/California/2009/38 (H1N1) virus. These results suggest that the HA-F DNA vaccine is a competitive vaccine candidate and presents a promising vaccination approach against influenza viruses.

Evidence of gas-phase pyranose-to-furanose isomerization in protonated peptidoglycans

Peptidoglycans are diverse co- and post-translational modifications of key importance in myriad biological processes. Mass spectrometry is employed to infer their biomolecular sequences and stereochemisties, but little is known about the critical gas-phase dissociation processes involved. Here, using tandem mass spectrometry (MS/MS and MSⁿ), isotopic labelling and high-level simulations, we identify and characterize a facile isomerization reaction that produces furanose N-acetylated ions. This reaction occurs for both O- and N-linked peptidoglycans irrespective of glycosidic linkage stereochemistry (α/β). Dissociation of the glycosidic and other bonds thus occur from the furanose isomer critically altering the reaction feasibility and product ion structures.

POS0442 RELATIONSHIP BETWEEN PARAOXONASE-1 GENOTYPE, ACTIVITY AND MAJOR ADVERSE CARDIOVASCULAR EVENTS IN PATIENTS WITH RHEUMATOID ARTHRITIS RECEIVING TOFACITINIB

Background:

Paraoxonase-1 (PON1) is a high-density lipoprotein (HDL)-associated enzyme with paraoxonase, lactonase and arylesterase activities.1 PON1 contributes to the antioxidant properties of HDL, and is being investigated for its atheroprotective properties.1 Patients (pts) with rheumatoid arthritis (RA) who are homozygous for the RR genotype of the Q192R gene polymorphism on PON1 (rs662) have increased paraoxonase activity, and lower risk of carotid plaques, vs those with QQ or QR genotypes.2 Tofacitinib is an oral Janus kinase inhibitor for the treatment of RA.

Objectives:

To investigate the relationship between PON1 genotype/activity and risk of major adverse cardiovascular events (MACE) in the tofacitinib RA clinical programme.

Methods:

In this post hoc analysis, data were pooled from pts enrolled in nine Phase 2/3 studies of tofacitinib in RA. Enzyme activities in pt plasma samples were measured at individual study baseline (BL) and at follow-up visits using three substrates: paraoxon (paraoxonase activity), dihydrocoumarin (lactonase activity) and phenylacetate (arylesterase activity). The effect of the PON1 Q192R genotype (QQ, QR or RR) on BL paraoxonase/lactonase/arylesterase activity was assessed using linear regression for each study, with age and sex as covariates, and then fixed-effect meta-analysis assessed effects across studies. The risk of MACE by enzyme activity was determined using Cox proportional hazards regression stratified by clinical studies. Univariate regression against BL enzyme activity and other risk factors, as well as both minimally and fully adjusted multivariable regressions against time-varying enzyme activity, are presented.

Results:

The analysis included 1969 pts with RA who received ≥1 dose of tofacitinib and had PON1 activity measures available at BL; 39 pts had ≥1 MACE event. Compared with the QQ genotype, the RR genotype had a highly significant positive association with BL paraoxonase activity, and a highly significant negative association with BL lactonase and arylesterase activity (Table 1). A univariate analysis identified several BL covariates significantly associated with risk of MACE (Figure 1a). Time-varying models found a highly significant association of increased paraoxonase activity over time with lower risk of future MACE, even after controlling for low-density lipoprotein or HDL cholesterol levels, and other traditional cardiovascular (CV) risk factors identified in univariate analysis (Figure 1b), with similar findings for lactonase and arylesterase (data not shown).

Table 1.

Effect of PON1 genotype (RR vs QQ) on BL enzyme activity

nEstimate95% CIp valueCochran’s Q testParaoxonase12291.0350.93, 1.141<0.00010.209Lactonase1188-0.375-0.505, -0.246<0.00010.025Arylesterase1231-1.016-1.382, -0.649<0.00010.251

Fixed-effects model; estimate >0 favours RR genotype and <0 favours QQ genotype

BL, baseline; CI, confidence interval

Conclusion:

Higher activity of the HDL-associated protein PON1 over time was associated with a significantly reduced risk of future MACE in pts with RA receiving tofacitinib, after controlling for traditional CV risk factors and cholesterol levels. Further investigation of PON1 as a novel functional lipid biomarker to assess CV risk in pts with RA is warranted.

References:

[1]Mackness & Mackness. Gene 2015; 567: 12-21.

[2]Charles-Schoeman et al. Arthritis Rheum 2013; 65: 2765-2772.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Jennifer Higginson, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

Christina Charles-Schoeman Consultant of: AbbVie, Gilead, Pfizer Inc, Regeneron-Sanofi, Grant/research support from: AbbVie, Bristol-Myers Squibb, Pfizer Inc, Craig Hyde Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Shunjie Guan Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Neil Parikh: None declared, Jennifer Wang: None declared, Ani Shahbazian: None declared, Lori Stockert Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, John Andrews Shareholder of: Pfizer Inc, Employee of: Pfizer Inc

Size Dependent Fragmentation Chemistry of Short Doubly Protonated Tryptic Peptides

Tandem mass spectrometry of electrospray ionized multiply charged peptide ions is commonly used to identify the sequence of peptide(s) and infer the identity of source protein(s). Doubly protonated peptide ions are consistently the most efficiently sequenced ions following collision-induced dissociation of peptides generated by tryptic digestion. While the broad characteristics of longer (N ≥ 8 residue) doubly protonated peptides have been investigated, there is comparatively little data on shorter systems where charge repulsion should exhibit the greatest influence on the dissociation chemistry. To address this gap and further understand the chemistry underlying collisional-dissociation of doubly charged tryptic peptides, two series of analytes ([G_xR+2H]²⁺ and [A_xR+2H]²⁺, x = 2-5) were investigated experimentally and with theory. We find distinct differences in the preference of bond cleavage sites for these peptides as a function of size and to a lesser extent composition. Density functional calculations at two levels of theory predict that the threshold relative energies required for bond cleavages at the same site for peptides of different size are quite similar (for example, b₂-y_N-2). In isolation, this finding is inconsistent with experiment. However, the predicted extent of entropy change of these reactions is size dependent. Subsequent RRKM rate constant calculations provide a far clearer picture of the kinetics of the competing bond cleavage reactions enabling rationalization of experimental findings. The M06-2X data were substantially more consistent with experiment than were the B3LYP data.

Gas-Phase Dissociation Chemistry of Deprotonated RGD

We investigate the structure and dissociation pathways of the deprotonated amphoteric peptide arginylglycylasparic acid, [RGD-H]^-. We model the pertinent gas-phase structures and fragmentation chemistry of the precursor anions and predominant sequence-informative bond cleavages (b₂+H₂O, c₂, and z₁ peaks) and compare these predictions to our tandem mass spectra and infrared spectroscopy experiments. Formation of the b₂+H₂O anions requires rate-limiting intramolecular back biting to cleave the second amide bond and generate an anhydride structure. Facile cleavage of the newly formed ester bond with concerted expulsion of a cyclic anhydride neutral generates the product structure. IR spectroscopy supports this b₂+H₂O anion having structures that are essentially identical to C-terminally deprotonated arginylglycine, [RG-H]^-. Formation of the c₂ anion is predicted to require concerted expulsion of CO₂ from the aspartyl side chain carboxylate and cleavage of the N-C_alpha bond to produce a proton-bound dimer of arginylglycinamide and acrylate. Proton transfers within the dimer then enable predominant detection of a c₂ anion with the negative charge nominally on the central, glycine nitrogen (amidate structure) as the proton affinity of this structure is predicted to be lower than acrylate by ∼27 kJ mol^-1. Alternate means of cleaving the same N-C_alpha bond produce deprotonated cis-1,4-dibut-2-enoic acid z₁ anion structures. These lowest energy processes involve C-H proton mobilization from the aspartyl side chain prior to N-C_alpha bond cleavage consistent with proposals from the literature.

[Analysis of emergency venous sinus stenting in the treatment of acute visual impairment caused by idiopathic cranial hypertension]

Objective: To investigate the efficacy and safety of emergency venous sinus stenting in the treatment of acute visual impairment caused by idiopathic intracranial hypertension (IIH). Methods: A descriptive cross-sectional study design was used to retrospectively analyze 38 patients undergoing venous sinus stenting in the First Affiliated Hospital of Zhengzhou University from January 2013 to October 2019. A total of 9 patients who had sudden short-term vision loss met the inclusion criteria. Routine visual field and fundus examination were performed. The venous sinus stenosis (CVSS) was confirmed by MR venography or DSA. The pressure gradient at both ends of CVSS was ≥10 mmHg(1 mmHg=0.133 kPa). All patients were treated with emergency venous sinus stenting. Six-month follow-up data were collected for comparison, evaluation of the therapeutic effect, and observation of adverse reactions. Results: All 9 patients were successfully treated with venous sinus stent. The pressure gradient at the distal and proximal ends of the stenosis after stent implantation decreased to (2.3±1.2) mmHg. After 6 months of follow-up, the papilledema was significantly improved or disappeared in all patients. The average grade of papilledema decreased from 2.44±0.73 before operation to 0.56±0.53 after treatment (t=6.314, P<0.001). The visual acuity of 9 patients recovered to the pre-onset level or improved significantly after 6 months. The average baseline value of preoperative visual acuity (logMAR) was 0.12±0.11, which increased to 0.74±0.13 on average 6 months after operation (t=-10.827, P<0.001). No recurrence of symptoms or serious adverse reactions occurred in all patients during the follow-up period. Conclusion: For patients with acute visual impairment caused by idiopathic cranial hypertension, emergency venous sinus stenting is a relatively safe and effective treatment that can effectively improve visual acuity.

Role of PTH1R Signaling in Prx1+ Mesenchymal Progenitors during Eruption

Tooth eruption is a complex process requiring precise interaction between teeth and adjacent tissues. Molecular analysis demonstrates that bone remodeling plays an essential role during eruption, suggesting that a parathyroid hormone 1 receptor (PTH1R) gene mutation is associated with disturbances in bone remodeling and results in primary failure of eruption (PFE). Recent research reveals the function of PTH1R signaling in mesenchymal progenitors, whereas the function of PTH1R in mesenchymal stem cells during tooth eruption remains incompletely understood. We investigated the specific role of PTH1R in Prx1⁺ progenitor expression during eruption. We found that Prx1⁺-progenitors occur in mesenchymal stem cells residing in alveolar bone marrow surrounding incisors, at the base of molars and in the dental follicle and pulp of incisors. Mice with conditional deletion of PTH1R using the Prx1 promoter exhibited arrested mandibular incisor eruption and delayed molar eruption. Micro-computed tomography, histomorphometry, and molecular analyses revealed that mutant mice had significantly reduced alveolar bone formation concomitant with downregulated gene expression of key regulators of osteogenesis in PTH1R-deficient cells. Moreover, culturing orofacial bone-marrow-derived mesenchymal stem cells (OMSCs) from Prx1Cre;PTH1R^fl/fl mice or from transfecting Cre recombinase adenovirus in OMSCs from PTH1R^fl/fl mice suggested that lack of Pth1r expression inhibited osteogenic differentiation in vitro. However, bone resorption was not affected by PTH1R ablation, indicating the observed reduced alveolar bone volume was mainly due to impaired bone formation. Furthermore, we found irregular periodontal ligaments and reduced Periostin expression in mutant incisors, implying loss of PTH1R results in aberrant differentiation of periodontal ligament cells. Collectively, these data suggest that PTH1R signaling in Prx1⁺ progenitors plays a critical role in alveolar bone formation and periodontal ligament development during eruption. These findings have implications for our understanding of the physiologic and pathologic function of PTH1R signaling in tooth eruption and the progression of PFE.

Palmatine alleviates hyperalgesia by inhibiting the expression of calcitonin gene-related peptide in the trigeminal ganglion of rats with chronic constriction injury of the infraorbital nerve

Trigeminal neuralgia is one of the most common of the neuropathic pains, and it can seriously influence patients' quality of life. Calcitonin gene-related peptide (CGRP) is a type of nociceptive neurotransmitter that is expressed in neurons of the trigeminal ganglion and plays a major part in transmitting pain. The rat model of trigeminal neuralgia was established by causing a chronic constriction injury of the infraorbital nerve (CCI-ION). Male Sprague-Dawley rats (n=24) were randomly divided into a sham control group (sham, n=6), sham-treated with palmatine group (sham+palmatine, n=6), trigeminal nerve model group (TN, n=6), and trigeminal nerve treated with palmatine group (TN+palmatine, n=6). Fifteen days after the operation the mechanical response threshold was decreased in the TN group compared with the sham group. From postoperative day 7 to day 15, the mechanical response threshold in the TN+palmatine group significantly increased compared with the TN group. On postoperative day 15 the results of quantitative polymerase chain reaction (qPCR), immunohistochemical staining, and western blotting showed an obvious increase in expression of CGRP and its receptors, serum concentrations of interleukin-1β (IL-1β), and tumour necrosis factor-α (TNF-α), and phosphorylation of protein kinase C (PKC) in the trigeminal ganglia of the TN group compared with the sham group, but these increases could be down-regulated by treatment with palmatine. Palmatine might therefore have therapeutic potential for the treatment of trigeminal neuralgia by inhibiting the expression of CGRP and its receptors in trigeminal ganglia, suppressing the serum concentrations of IL-1β and TNF-α, and decreasing the phosphorylation of PKC in the trigeminal ganglia of affected rats.

Exploration of Binding Mechanism of a Potential Streptococcus pneumoniae Neuraminidase Inhibitor from Herbaceous Plants by Molecular Simulation

Streptococcus pneumoniae can cause diseases such as pneumonia. Broad-spectrum antibiotic therapy for Streptococcus pneumoniae is increasingly limited due to the emergence of drug-resistant strains. The development of novel drugs is still currently of focus. Abundant polyphenols have been demonstrated to have antivirus and antibacterial ability. Chlorogenic acid is one of the representatives that has been proven to have the potential to inhibit both the influenza virus and Streptococcus pneumoniae. However, for such a potential neuraminidase inhibitor, the interaction mechanism studies between chlorogenic acid and Streptococcus pneumoniae neuraminidase are rare. In the current study, the binding mechanism of chlorogenic acid and Streptococcus pneumoniae neuraminidase were investigated by molecular simulation. The results indicated that chlorogenic acid might establish the interaction with Streptococcus pneumoniae neuraminidase via hydrogen bonds, salt bridge, and cation-π. The vital residues involved Arg347, Ile348, Lys440, Asp372, Asp417, and Glu768. The side chain of Arg347 might form a cap-like structure to lock the chlorogenic acid to the active site. The results from binding energy calculation indicated that chlorogenic acid had strong binding potential with neuraminidase. The results predicted a detailed binding mechanism of a potential Streptococcus pneumoniae neuraminidase inhibitor, which will be provide a theoretical basis for the mechanism of new inhibitors.

[Clinical analysis of 382 immediately breast reconstruction after mastectomy in Beijing City, Tianjin City and Hebei Province from 2012 to 2016]

Objective: To summarize the status of immediate breast reconstruction (IBR) after mastectomy in Beijing City, Tianjin City and Hebei Province. Methods: A retrospective analysis was made on the data of 382 cases with breast cancer who were treated and followed up successfully with immediate breast reconstruction after mastectomy from January 2012 to December 2016 in Beijing City, Tianjin City and Hebei Province. Clinic data of the followed-up 382 cases (all female, age (38.5±4.2) years (range: 24 to 70 years)), including general information, tumor information, sugery methods, and treatments after surgery were collected. The survival status, metastasis,complications and prognosis were followed up. Cosmetic effcet was evalated by Harris method, and life quality by Functional Assessment of Cancer Therapy-Breast scale (FACT-B). χ(2) test was used to compare the difference between year 2012 and year 2013 to 2016. Bonferroni method was used to correct the inspection level, which was 0.05/10=0.005. The trend of IBR rate (ratio of IBR to modified radical mastectomy) from 2013 to 2016 was analyzed by trend χ(2) test. Results: There was 46 cases in stage 0, 152 cases in stage Ⅰ, 165 cases in stage Ⅱ, 19 cases in stage Ⅲ. Twenty-five cases was treated by neoadjuvant chemotherapy, 231 by chemotherapy and 35 by radiotherapy. The proportion of implant reconstruction was 48.7% (186/382), more than expanded of 21.5% (82/382), with latissimus dorsi of 12.0% (46/382), TRAM of 8.9% (34/382), DIEP of 2.1% (8/382), and latissimus plus implant of 6.8% (26/382). According to the Harris standard, the excellent and good rate of the cosmetic effect of the reconstructed breast was 93.7%. The score of FACT-B was 108.20±16.9 (range: 67 to 144) 1 year postoperatively. Compared with 2012, the IBR rate was significant increased, till 2015, the IBR rate was 153/10 000 cases (χ(2)=47.028, P=0.000). Conclusions: There is a significant increase on IBR rate in Beijing City, Tianjin City and Hebei province by year. Most of cases received IBR is stage Ⅰ to Ⅱ. Implant reconstruction is the main reconstructive method. Postoperative cosmetic effects and quality of life are both meet patients' demon.

Leaving Group Effects in a Series of Electrosprayed CcHhN1 Anthracene Derivatives

We investigate the gas-phase structures and fragmentation pathways of model compounds of anthracene derivatives of the general formula C_cH_hN₁ utilizing tandem mass spectrometry and computational methods. We vary the substituent alkyl chain length, composition, and degree of branching. We find substantial experimental and theoretical differences between the linear and branched congeners in terms of fragmentation thresholds, available pathways, and distribution of products. Our calculations predict that the linear substituents initially isomerize to form lower energy branched isomers prior to loss of the alkyl substituents as alkenes. The rate-determining chemistry underlying these related processes is dominated by the ability to stabilize the alkene loss transition structures. This task is more effectively undertaken by branched substituents. Consequently, analyte lability systematically increased with degree of branching (linear < secondary < tertiary). The resulting anthracen-9-ylmethaniminium ion generated from these alkene loss reactions undergoes rate-limiting proton transfer to enable expulsion of either hydrogen cyanide or CNH. The combination of the differences in primary fragmentation thresholds and degree of radical-based fragmentation processes provide a potential means of distinguishing compounds that contain branched alkyl chain substituents from those with linear ones.

Elastocapillary self-assembled neurotassels for stable neural activity recordings

Implantable neural probes that are mechanically compliant with brain tissue offer important opportunities for stable neural interfaces in both basic neuroscience and clinical applications. Here, we developed a Neurotassel consisting of an array of flexible and high-aspect ratio microelectrode filaments. A Neurotassel can spontaneously assemble into a thin and implantable fiber through elastocapillary interactions when withdrawn from a molten, tissue-dissolvable polymer. Chronically implanted Neurotassels elicited minimal neuronal cell loss in the brain and enabled stable activity recordings of the same population of neurons in mice learning to perform a task. Moreover, Neurotassels can be readily scaled up to 1024 microelectrode filaments, each with a neurite-scale cross-sectional footprint of 3 × 1.5 μm², to form implantable fibers with a total diameter of ~100 μm. With their ultrasmall sizes, high flexibility, and scalability, Neurotassels offer a new approach for stable neural activity recording and neuroprosthetics.

Screening HCV genotype-specific epitope peptides based on conserved sequence analysis and B cell epitope prediction in HCV E2 region

The high mutation rate of the hepatitis C virus (HCV) genome increases the genotype diversity and renders the detection of the virus more difficult. Therefore, prediction and assessment of highly conserved and strongly antigenic epitope polypeptide sequences have become a focus of current research. The E2 region is the target binding region of neutralizing antibodies. HCV genomics, especially the high mutation rate of E2 region sequence, makes its genotyping more and more diverse, and the detection of HCV and genotype is becoming more and more strict. In this study, four HCV B cell epitope polypeptides were constructed based on assessment of conserved sequences in the HCV E2 region and prediction of B cell epitopes, including sequences specific to genotype 1A (DC-13: 434-DTGWLAGLFYYHK-446), genotype 1B (HC-13: 434-HTGFLAALFYAKS-446), genotype 4D (NC-13: 434-NTGFLASLFYTHK-446), and a consensus sequence (FC-9: 447-FNSSGCPER-455). Epitope polypeptides combined with serum from 29 HCV-infected or 25 non-HCV-infected individuals were assayed by enzyme-linked immunosorbent assay (ELISA), and differences were analyzed by T/T' test methods in SPSS v20.0 software. Binding levels of genotype 1A, 4D, and consensus epitope polypeptides with sera of HCV-infected patients were higher than those of non-infected individuals. Moreover, binding of genotype 1B epitope polypeptides with serum of HCV 1B-infected patients was higher than that of HCV 2A-infected patients. While the screening results of HCV genotype-specific epitope polypeptides were preliminary, these findings indicated that we successfully established an HCV and genotype serological ELISA detection method. Such an approach would facilitate the discovery of epitope polypeptides which may become new antigen candidates in peptide vaccine development for the prevention of HCV infection.

Effect of Chemical Structure on the Performance of Sulfonated Poly(aryl ether sulfone) Composite Nanofiltration Membranes

This paper discusses the effect of the chemical structure of sulfonated poly(aryl ether sulfone) on the performance of composite nanofiltration membranes. The composite nanofiltration membranes were fabricated by coating sulfonated poly(aryl ether sulfone) solution onto the top surface of poly(phthalazinone ether sulfone ketone) support membranes. Three kinds of sulfonated poly(aryl ether sulfone)s with different amounts of phthalazinone moieties, namely, sulfonated poly(phthalazinone ether sulfone) (SPPES), sulfonated poly(phthalazinone biphenyl ether sulfone) (SPPBES), and sulfonated poly(phthalazinone hydroquinone ether sulfone)s (SPPHES), were used as coating materials. The solvents used in preparing the coating solution were investigated and optimized. The separation properties, thermal stability, and chlorine resistance of composite membranes were determined. The structures and morphologies of membranes were characterized with FTIR and SEM, respectively. The membrane prepared from SPPES with more phthalazinone moiety groups showed high water flux and salt rejection. The salt rejection of composite membranes followed the order SPPES > SPPHES > SPPBES. The rejection of the three composite membranes decreased slightly with the solution temperature rising from 20 to 90 °C, while the composite membrane with SPPES as the active layer showed a higher increase in flux than others. The results indicate that SPPES composite membranes show better thermal stability than others.

Effects of Tyr555 and Trp678 on the processivity of cellobiohydrolase A from Ruminiclostridium thermocellum: A simulation study

Cellobiohydrolase A from Ruminiclostridium thermocellum (Cbh9A) is a processive exoglucanase from family 9 and is an important cellobiohydrolase that hydrolyzes cello-oligosaccharide into cellobiose. Residues Tyr555 and Trp678 considerably affect catalytic activity, but their mechanisms are still unknown. To investigate how the Tyr555 and Trp678 affect the processivity of Cbh9A, conventional molecular dynamics, steered molecular dynamics, and free energy calculation were performed to simulate the processive process of wild type (WT)-Cbh9A, Y555S mutant, and W678G mutant. Analysis of simulation results suggests that the binding free energies between the substrate and WT-Cbh9A are lower than those of Y555S and W678G mutants. The pull forces and energy barrier in Y555S and W678G mutants also reduced significantly during the steered molecular dynamics (SMD) simulation compared with that of the WT-Cbh9A. And the potential mean force calculations showed that the pulling energy barrier of Y555S and W678G mutants is much lower than that of WT-Cbh9A.

Humanization and directed evolution of the selenium-containing scFv phage abzyme

According to the binding site structure and the catalytic mechanism of the native glutathione peroxidase (GPX), three glutathione derivatives, GSH-S-DNP butyl ester (hapten Be), GSH-S-DNP hexyl ester (hapten He) and GSH-S-DNP hexamethylene ester (hapten Hme) were synthesized. By a four-round panning with a human synthetic scFv phage library against three haptens, the enrichment of the scFv phage particles with specific binding activity could be determined. Three phage particles were selected binding to each glutathione derivative, respectively. After a two-step chemical mutation to convert the serine residues of the scFv phage particles into selenocysteine residues, GPX activity could be observed and determined upto 3000 U μmol^-1 in the selenium-containing scFv phage abzyme which was isolated by affinity capture against the hapten Be. Also the scFv phage abzymes elicited by different antigens displayed different catalytic activities. After a directed evolution by DNA shuffling to improve the affinity to the hapten Be, a secondary library with GPX activity was created in which the catalytic activity of the selenium-containing scFv phage abzyme could be increased 17%. This study might be helpful for new haptens or antigens design to optimize the abzymes with high binding activities and might also provide a novel scheme for GPX mimic candidates for drug development.

Insight into the process of product expulsion in cellobiohydrolase Cel6A from Trichoderma reesei by computational modeling

Glycoside hydrolase cellulase family 6 from Trichoderma reesei (TrCel6A) is an important cellobiohydrolase to hydrolyze cellooligosaccharide into cellobiose. The knowledge of enzymatic mechanisms is critical for improving the conversion efficiency of cellulose into ethanol or other chemicals. However, the process of product expulsion, a key component of enzymatic depolymerization, from TrCel6A has not yet been described in detail. Here, conventional molecular dynamics and steered molecular dynamics (SMD) were applied to study product expulsion from TrCel6A. Tyr103 may be a crucial residue in product expulsion given that it exhibits two different posthydrolytic conformations. In one conformation, Tyr103 rotates to open the -3 subsite. However, Tyr103 does not rotate in the other conformation. Three different routes for product expulsion were proposed on the basis of the two different conformations. The total energy barriers of the three routes were calculated through SMD simulations. The total energy barrier of product expulsion through Route 1, in which Tyr103 does not rotate, was 22.2 kcal·mol^-1. The total energy barriers of product expulsion through Routes 2 and 3, in which Tyr103 rotates to open the -3 subsite, were 10.3 and 14.4 kcal·mol^-1, respectively. Therefore, Routes 2 and 3 have lower energy barriers than Route 1, and Route 2 is the thermodynamically optimal route for product expulsion. Consequently, the rotation of Tyr103 may be crucial for product release from TrCel6A. Results of this work have potential applications in cellulase engineering.

The deposition of metal nanoparticles on carbon surfaces: the role of specific functional groups

The influence of hydroxyl and carbonyl groups on the deposition of gold from solution onto graphite surfaces was explored: OH gives Au⁰ whereas CO results in Au³⁺.

Effects of poly(I:C) and MF59 co-adjuvants on immunogenicity and efficacy of survivin polypeptide immunogen against melanoma

Malignant tumors pose a public health problem that jeopardizes human life and quality of living. At present, tumor vaccines in clinical research typically are aimed at stimulating the cellular immune response, while more effective vaccines should take into account the synergy between broad spectrum antibodies and high levels of cellular immunity. In this study, epitope peptides (68-81, 95-104, 80-88) of the tumor antigen survivin were chosen as immunogens and supplemented with poly(I:C) and/or MF59 adjuvant to evaluate the immune effects and anti-melanoma activities. The results indicated that poly(I:C) and MF59 could assist the survivin epitope peptide immunogen to control the tumor size, quality, and volume in black melanoma mouse models. Analyses by antibody titering, antibody isotyping and ELISPOT suggested that the adjuvanted immunogen could induce humoral immunity in mice. Poly(I:C) and MF59 combined with survivin peptide 95-104 could effectively induce humoral immunity mediated by type 2 T helper (Th2) cells. This study provides a basis for candidate immunogen design based on survivin and provides support for tumor therapy that can induce a more balanced Th1/Th2 immune response.

Cationized Carbohydrate Gas-Phase Fragmentation Chemistry

We investigate the fragmentation chemistry of cationized carbohydrates using a combination of tandem mass spectrometry, regioselective labeling, and computational methods. Our model system is D-lactose. Barriers to the fundamental glyosidic bond cleavage reactions, neutral loss pathways, and structurally informative cross-ring cleavages are investigated. The most energetically favorable conformations of cationized D-lactose were found to be similar. In agreement with the literature, larger group I cations result in structures with increased cation coordination number which require greater collision energy to dissociate. In contrast with earlier proposals, the B _n -Y _m fragmentation pathways of both protonated and sodium-cationized analytes proceed via protonation of the glycosidic oxygen with concerted glycosidic bond cleavage. Additionally, for the sodiated congeners our calculations support sodiated 1,6-anhydrogalactose B _n ion structures, unlike the preceding literature. This affects the subsequent propensity of formation and prediction of B _n /Y _m branching ratio. The nature of the anomeric center (α/β) affects the relative energies of these processes, but not the overall ranking. Low-energy cross-ring cleavages are observed for the metal-cationized analytes with a retro-aldol mechanism producing the ^0,2 A ₂ ion from the sodiated forms. Theory and experiment support the importance of consecutive fragmentation processes, particularly for the protonated congeners at higher collision energies. Graphical Abstract ᅟ.

Therapy of tacrolimus combined with corticosteroids in idiopathic membranous nephropathy

We evaluated the efficacy and safety of tacrolimus (TAC) combined with corticosteroids in treating patients with idiopathic membranous nephropathy (IMN). One hundred seventy-seven biopsy-proven IMN patients were recruited in this retrospective clinical study. Sixty patients received TAC (target blood concentration of 4–8 ng/mL) and 117 patients received daily cyclophosphamide (CYC, 100 mg) combined with prednisone. Remission rates at the end of the first, second and third month in the TAC group were significantly higher than that in the CYC group (1st: 35.0 vs 19.7%, P<0.05; 2nd: 56.7 vs 38.5%, P<0.05; 3rd: 76.7 vs 59.0%, P<0.05). In the first 3 months, daily urinary protein and serum albumin in the TAC group obtained a better improvement than that in the CYC group (P<0.05). At the end of the sixth and the twelfth month, the remission rates, daily urinary protein and serum albumin were all comparable between the two groups (P>0.05). No significant difference of relapse rate between the groups was found (16.3 vs 12.0%, P>0.05). Patients were more likely to develop glucose intolerance in the TAC group. The TAC regimen obtained more benefits in treating IMN patients, especially in the first 3 months, than the CYC regimen.

[Endoscopic nipple-sparing mastectomy with skin lifting system followed by immediate breast reconstruction]

Objective: To discuss the surgical treatment and efficacy of endoscopic nipple-sparing mastectomy with skin lifting system (ENSMSLS) followed by immediate breast reconstruction. Methods: ENSMSLS was conducted on 21 patients followed by immediate breast reconstruction with implant via axillary incision from August 2014 to January 2016 in Oncology Center, Beijing Tongren Hospital, Capital Medical University. These 21 patients were frequency matched with 21 patients, who received nipple-sparing mastectomy via loop periareolar incision from November 2012 to May 2015 in the same center. These 21 patients formed the control group. The operation data of two groups were compared by t test and Fisher's exact test. Results: Differences in operation time ((185±43) minutes vs. (165±33) minutes, t=1.778, P=0.101), amount of bleeding ((60±48) ml vs. (75±57) ml, t=-0.535, P=0.329), and drainage ((240±112) ml vs. (201±91) ml, t=1.238, P=0.233) between these two groups of patients were not statistically significant. There was no nipple necrosis recorded in the ENSMSLS group, while there were three cases (14.3%) recorded in the control group. Two cases (9.5%) of nipple transposition were recorded in the ENSMSLS group, while five cases (23.8%) were recorded in the control group. Differences in nipple necrosis and nipple transposition were statistically significant (0 vs. 5, P=0.001). There were 16 cases (76.2%) of excellent appearance recorded in the ENSMSLS group, while there were 11 cases (52.4%) recorded in the control group. There were 5 cases (23.8%) of good appearance recorded in the ENSMSLS group, while there were 9 cases (42.9%) recorded in the control group. There was no case of fair appearance in the ENSMSLS group, while there was 1 case (4.8%) recorded in the control group. Difference in postoperative appearance was statistically significant (P=0.001). Conclusions: ENSMSLS significantly decreases the possibility of nipple necrosis and nipple transposition. This technique avoids visible incisions of breast. It also enhances the aesthetic appeal of reconstructed breasts.

Frailty in Relation to the Risk of Alzheimer's Disease, Dementia, and Death in Older Chinese Adults: A Seven-Year Prospective Study

OBJECTIVES

To explore the relationship of general health decline assessed by frailty and risk of dementia and Alzheimer's disease (AD).

DESIGN

A seven-year prospective cohort study.

SETTING

Secondary analysis of data from the Beijing Longitudinal Study on Aging.

PARTICIPANTS

Urban and rural community-dwelling people aged 60 and older at baseline.

MEASUREMENTS

Frailty was quantified using the deficit accumulation-based frailty index (FI), constructed from 40 health deficits at baseline. Dementia was diagnosed by DSM-IIIR. AD and vascular dementia (VaD) were diagnosed by NINCDS-ADRDA and NINDS-AIREN. The relationships between frailty and the risk of dementia, AD and death were evaluated through multivariable models.

RESULTS

Of 2788 participants at baseline (1997), 171 (11.1%) reported a history of dementia. In seven years, 351 people developed dementia (13%: 223 AD and 128 other types of dementia) and 813 died (29%). After adjustment for age, sex, education, and baseline cognition, baseline frailty status significantly associated with Alzheimer's disease and dementia and death. For each deficit accumulated, the odds ratio of death increased by 5.7%, and the odds ratio of dementia increased by 2.9% (p < 0.001).

CONCLUSION

Frailty was associated with Alzheimer's disease and dementia over a seven years period. Frailty index might facilitate the identification of older adults at high risk of dementia for the application of the most effective, targeted prevention strategies.

Stereochemical Sequence Ion Selectivity: Proline versus Pipecolic-acid-containing Protonated Peptides

Substitution of proline by pipecolic acid, the six-membered ring congener of proline, results in vastly different tandem mass spectra. The well-known proline effect is eliminated and amide bond cleavage C-terminal to pipecolic acid dominates instead. Why do these two ostensibly similar residues produce dramatically differing spectra? Recent evidence indicates that the proton affinities of these residues are similar, so are unlikely to explain the result [Raulfs et al., J. Am. Soc. Mass Spectrom. 25, 1705-1715 (2014)]. An additional hypothesis based on increased flexibility was also advocated. Here, we provide a computational investigation of the "pipecolic acid effect," to test this and other hypotheses to determine if theory can shed additional light on this fascinating result. Our calculations provide evidence for both the increased flexibility of pipecolic-acid-containing peptides, and structural changes in the transition structures necessary to produce the sequence ions. The most striking computational finding is inversion of the stereochemistry of the transition structures leading to "proline effect"-type amide bond fragmentation between the proline/pipecolic acid-congeners: R (proline) to S (pipecolic acid). Additionally, our calculations predict substantial stabilization of the amide bond cleavage barriers for the pipecolic acid congeners by reduction in deleterious steric interactions and provide evidence for the importance of experimental energy regime in rationalizing the spectra. Graphical Abstract ᅟ.