[Association of sleep duration and risk of frailty among the elderly over 80 years old in China: a prospective cohort study]

Objective: To explore the association between sleep duration and the risk of frailty among the elderly over 80 years old in China. Methods: Using the data from five surveys of the China Elderly Health Influencing Factors Follow-up Survey (CLHLS) (2005, 2008-2009, 2011-2012, 2014, and 2017-2018), 7 024 elderly people aged 80 years and above were selected as the study subjects. Questionnaires and physical examinations were used to collect information on sleep time, general demographic characteristics, functional status, physical signs, and illness. The frailty state was evaluated based on a frailty index that included 39 variables. The Cox proportional risk regression model was used to analyze the correlation between sleep time and the risk of frailty occurrence. A restricted cubic spline function was used to analyze the dose-response relationship between sleep time and the risk of frailty occurrence. The likelihood ratio test was used to analyze the interaction between age, gender, sleep quality, cognitive impairment, and sleep duration. Results: The age M (Q₁, Q₃) of 7 024 subjects was 87 (82, 92) years old, with a total of 3 435 (48.9%) patients experiencing frailty. The results of restricted cubic spline function analysis showed that there was an approximate U-shaped relationship between sleep time and the risk of frailty. When sleep time was 6.5-8.5 hours, the elderly had the lowest risk of frailty; Multivariate Cox proportional risk regression model analysis showed that compared to 6.5-8.5 hours of sleep, long sleep duration (>8.5 hours) increased the risk of frailty by 13% (HR: 1.13; 95%CI: 1.04-1.22). Conclusion: There is a nonlinear association between sleep time and the risk of frailty in the elderly.

Characterization and Immunogenicity of Influenza H7N9 Vaccine Antigens Produced Using a Serum-Free Suspension MDCK Cell-Based Platform

Human infections with avian-origin H7N9 influenza A viruses were first reported in China, and an approximately 38% human mortality rate was described across six waves from February 2013 to September 2018. Vaccination is one of the most cost-effective ways to reduce morbidity and mortality during influenza epidemics and pandemics. Egg-based platforms for the production of influenza vaccines are labor-intensive and unable to meet the surging demand during pandemics. Therefore, cell culture-based technology is becoming the alternative strategy for producing influenza vaccines. The current influenza H7N9 vaccine virus (NIBRG-268), a reassortant virus from A/Anhui/1/2013 (H7N9) and egg-adapted A/PR/8/34 (H1N1) viruses, could grow efficiently in embryonated eggs but not mammalian cells. Moreover, a freezing-dry formulation of influenza H7N9 vaccines with long-term stability will be desirable for pandemic preparedness, as the occurrence of influenza H7N9 pandemics is not predictable. In this study, we adapted a serum-free anchorage-independent suspension Madin-Darby Canine Kidney (MDCK) cell line for producing influenza H7N9 vaccines and compared the biochemical characteristics and immunogenicity of three influenza H7N9 vaccine antigens produced using the suspension MDCK cell-based platform without freeze-drying (S-WO-H7N9), the suspension MDCK cell-based platform with freeze-drying (S-W-H7N9) or the egg-based platform with freeze-drying (E-W-H7N9). We demonstrated these three vaccine antigens have comparable biochemical characteristics. In addition, these three vaccine antigens induced robust and comparable neutralizing antibody (NT; geometric mean between 1016 and 4064) and hemagglutinin-inhibition antibody (HI; geometric mean between 640 and 1613) titers in mice. In conclusion, the serum-free suspension MDCK cell-derived freeze-dried influenza H7N9 vaccine is highly immunogenic in mice, and clinical development is warranted.

[Efficacy and safety of endothelin receptor antagonists combined with phosphodiesterase 5 inhibitor in the treatment of pulmonary arterial hypertension: a network meta-analysis]

Objective: To examine the efficacy and safety of endothelin receptor antagonists (ERA) combined with phosphodiesterase 5 inhibitors (PDE5i) in the treatment of pulmonary artery hypertension (PAH). Methods: Computer-based retrieval was performed on PubMed, Cochrane Library, CNKI, Wanfang, and VIP database (up to February 12th, 2021). Randomized controlled trials about endothelin receptor antagonists (ERAs) or PDE5i in patients with PAH were collected. The change of 6-minute walking distance (6MWD) in 12-16 weeks was used as primary outcome index. Case fatality rate, worsening clinical events, WHO functional class (FC) improvement, adverse events (AEs), serious adverse events (SAE) were the key secondary outcomes indicators. STATA 16.0 software was used for network meta-analysis, and the pooled estimates of odds ratios (ORs) or weighted mean differences (WMDs) and 95% confidence intervals (CIs) of the results were shown. To help explain ORs and WMDs, we used the surface under the cumulative ranking curve (SUCRA) to calculate the probability of each intervention. Results: We included 29 trials with 5 949 participants. In network meta-analysis, Bosentan combined with Sildenafil (WMD=53.93, 95%CI=6.19-101.66) had shown the greatest improvement in 6MWD compared with placebo, followed by Bosentan combined with Tadalafil (WMD=50.84, 95%CI=7.05-94.62), Ambrisentan combined with Tadalafil (WMD=46.67, 95%CI=15.88-77.45), Bosentan (WMD=29.44, 95%CI=5.86-53.02), Ambrisentan (WMD=23.90, 95%CI=0.31-47.48) and Macitentan (WMD=21.57, 95%CI=2.45-40.69). According to SUCRA, the effects of different intervention measures on improving 6MWD in patients with arterial pulmonary hypertension were as follows: Bosentan+Sildenafil (82.9%)>Bosentan+Tadalafil (78.4%)>Ambrisentan+Tadalafil (77.1%)>Bosentan (49.2%)>Sildenafil (48.5%)>Ambrisentan (40.3%)>Macitentan (37.3%)>Tadalafil (33.0%)>Placebo (3.3%). For the WHO functional class, Sildenafil (OR=2.90, 95%CI=1.04-8.08) was optimal compared with placebo, followed by Bosentan (OR=2.15, 95%CI=1.15-4.04), and there was no significant difference in the rest. For clinical worsening, Bosentan combined with Tadalafil (OR=0.08, 95%CI=0.01-0.49) performed best compared with placebo, followed by Bosentan (OR=0.20, 95%CI=0.11-0.38), Bosentan combined with Sildenafil (OR=0.21, 95%CI=0.09-0.46), Ambrisentan combined with Tadalafil (OR=0.27, 95%CI=0.15-0.50), Sildenafil (OR=0.33, 95%CI=0.17-0.66) and Tadalafil (OR=0.44, 95%CI=0.21-0.90). There was no statistical difference between all interventions and placebo in terms of the incidence of adverse events and serious adverse events. For case fatality rate, Ambrisentan (OR=0.28, 95%CI=0.11-0.74) was statistically superior to placebo and there was no statistics difference in the rest. Conclusions: The combination therapy of ERAs and PDE5i performed well in the short-term improvement of motor function. Furthermore, there was no significant difference with monotherapy in terms of safety. However, it is worth emphasizing that the choice of treatment should be based on the patient's individualized situation and the patient's requirements.

[Change of innate lymphoid cell subsets in peripheral bloods and ascites in liver cirrhotic patients complicated with spontaneous bacterial peritonitis]

Objective: To investigate the change of innate lymphoid cells (ILC) subsets in peripheral blood and ascites in liver cirrhotic patients complicated with spontaneous bacterial peritonitis (SBP). Methods: The data of 62 patients with liver cirrhosis admited to the Zhumadian Central Hospital from November 2019 to November 2020 were analyzed. Among them, 41 cases were complicated with untainted ascites (untainted ascites group), while the other 21 cases were complicated with SBP (SBP group). Meanwhile, 20 cases of controls who received healthy examination in the same period were also enrolled (control group). Peripheral blood mononuclear cell (PBMC) was isolated from peripheral blood of all patients and controls. Mononuclear cell in ascites was isolated from patients with liver cirrhosis. The percentage of ILC1, ILC2, and ILC3 subsets in PBMC and mononuclear cell in ascites were measured by flow cytometry. CD3^-CD19^-CD20^-CD14^- cells (lin^-cells) were purified from ascites and were stimulated with lipopolysaccharide (LPS) for 24 h. The transcription factor T-bet, GATA3, and RORγt mRNA relative level in lin^-cells was semi-quantified by real-time PCR. Cytokine level in the supernatants was measured by enzyme linked immunosorbent assay. Differences of ILC subsets in peripheral blood and ascites were compared among groups. Results: There were twenty-nine males and twelve females in untainted ascites group, aged M(Q₁,Q₃) 49(33, 78) years. There were twelve males and nine females in SBP group, aged 50(37, 76) years. There were eleven males and nine females in control group, aged 48(32, 69) years. lin^-CD45⁺CD161⁺CD127⁺ ILC cells could be detected in both peripheral blood and ascites. There was no significant difference in total ILC percentage within PBMC among untainted ascites group, SBP group, and control group (P=0.235). There was also no significant difference of total ILC percentage within mononuclear cells in ascites between untainted ascites group and SBP group (P=0.232). The differences were not statistically significant of peripheral CD117^-CRTh2^-ILC1, CRTh2⁺ILC2, or CD117⁺CRTh2^-ILC3 within peripheral ILC among untainted ascites group, SBP group, and control group (all P>0.05). ILC1 percentage in ascites was up-regulated in SBP group compared with untainted ascites group (35.69%±3.39% vs 26.40%±3.85%, P<0.001), while ILC2 in ascites was down-regulated in SBP group (36.83%±7.70% vs 48.35%±9.45%, P<0.001). There was no statistical difference in ILC3 percentage in ascites between the two groups (P=0.230). T-bet mRNA relative level and IFN-γ production by lin^- cells from ascites were elevated in response to LPS stimulation in SBP group compared with untainted ascites group (both P<0.001). GATA3 mRNA relative level and IL-5/IL-13 secretion by lin^-cells from ascites were reduced in SBP group compared with untainted ascites group (both P<0.05). There was no significant difference of RORγt mRNA relative level or IL-17/IL-22 expression between the two groups (both P>0.05). Conclusion: Peripheral ILC subsets do not change in liver cirrhosis patients with SBP. ILC1 percentage is up-regulated, and ILC2 percentage is down-regulated in ascites in liver cirrhosis patients with SBP.

[Association between sleep duration and activity of daily living in the elderly aged 65 years and older in China]

Objective: To investigate the association between sleep duration and activity of daily living (ADL) in the elderly aged 65 years and older in China. Methods: A total of 11 247 subjects aged 65 and above were included in the Chinese Elderly Health Factors Tracking Survey from March 29, 2005 to April 8, 2019. Self-made questionnaire was used to collect the data of population sociological characteristics, health status and disease status. ADL status was assessed by basic activities of daily living. The association between sleep duration and ADL impairment was assessed by Cox proportional risk regression model. The dose-response relationship between sleep duration and ADL impairment was analyzed using restricted cubic spline function. Results: The age of the subjects was (79±10) years, including 5 793(51.5%) females. The incidence of ADL impairment was 33.3% (3 747/11 247). Subjects were divided into short, medium, and long sleep groups according to sleep duration of fewer than seven hours, seven to eight hours, or more than eight hours. The number of short, medium and long sleepers was 2 974 (26.4%), 4 922 (43.8%) and 3 351(29.8%), respectively. The intermediate sleep group had the lowest incidence of impaired ADL (4.98/100 person-years). Cox proportional risk regression model analysis showed that: taking the intermediate sleep group as reference, after adjustment of gender, age, marital status, educational level, place of residence, living with family, smoking, drinking, exercise, frequency of fruit consumption, vegetable intake frequency, sleep quality, factors such as hypertension, diabetes, heart disease and cerebrovascular disease, the long sleep time increased the risk of impaired ADL [HR (95%CI): 1.148 (1.062-1.241)]. Subgroup analysis showed a weak positive multiplicative interaction between sleep duration and age [HR (95%CI): 1.004 (1.000-1.009)], but no multiplicative interaction between sleep duration and sex [HR(95%CI): 0.948 (0.870-1.034)]. Longer sleep duration increased the risk of ADL impairment in women [HR (95%CI): 1.195 (1.074-1.329)], but not in men [HR (95%CI): 1.084 (0.966-1.217)]. Longer sleep duration increased the risk of ADL impairment in people aged 80 years and older [HR (95%CI): 1.185 (1.076-1.305)], but not in people younger than 80 years [HR (95%CI): 1.020 (0.890-1.169)]. There was a non-linear dose-response relationship between sleep duration and ADL damage (P=0.007), and the risk of ADL damage was lowest when sleep duration was 7.5 h. Conclusion: Sleep duration was positively correlated with the risk of ADL impairment in the elderly in a nonlinear dose-response relationship.

[Predictive value of serum ferritin and a new predictive model for intravenous immunoglobulin resistance in Kawasaki disease]

Objective: To evaluate the predictive value of serum ferritin (SF) and construct a novel predictive model for intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) (IVIGRKD). Methods: The clinical data of 422 children with KD from January 2017 to December 2019 in Quanzhou Women's and Children's Hospital were retrospectively analyzed. According to the response to IVIG, they were divided into IVIG-resistant group and IVIG-sensitive group. Forty-one clinical indicators including general characteristics and laboratory results were compared between the two groups. Comparisons between groups were performed with unpaired Student t test or Mann-Whitney U test or chi-square test. Receiver operating characteristic (ROC) curve was applied to evaluate the predictive value of SF for IVIGRKD. Binary Logistic regression analysis was used to test whether SF was an independent risk factor for IVIGRKD. Meanwhile, a novel predictive scoring system was established. The comparisons between the new predictive scoring system with four commonly used prediction scoring systems were conducted. Results: A total of 422 KD cases (285 males and 137 females, 17.0 (9.0,29.0) years of age) were enrolled and divided into IVIG-resistant group (n=57) and IVIG-sensitive group (n=365). Seventeen clinical indicators differed significantly between the two groups. SF level of the IVIG-resistant group was significantly higher than that of the sensitive group (245.0 (131.0, 519.0) vs. 145.0 (92.5, 232.5) μg/L, Z=-5.109, P<0.05). ROC curve showed that the Youden index of SF for predicting IVIGRKD was 0.326 (cutoff value 403.5 μg/L). Binary logistic regression analysis showed that SF, days of illness at initial IVIG treatment, cervical lymphadenopathy, pleomorphic rash, white blood cell, C-reactive protein (CRP), activated partial thromboplastin time (APTT), alanine transaminase (ALT) and creatinine were independent risk factors for IVIGRKD. A novel prediction model was constructed, and the cutoff points and score points were as follows: pleomorphic rash, 2 points; cervical lymphadenopathy, 1 point; SF≥ 403.5 μg/L, 1 point; white blood cell ≥ 18.3×10⁹/L, 1 point; CRP≥83.1 mg/L, 1 point; APTT≥25.3 s, 1 point; ALT≥37.5 U/L, 1 point. And patients with scores of 4 or more were at high-risk for IVIGRKD. The Youden index of the four commonly used scoring systems ranged from 0.315 to 0.512. However, the Youden index of the new scoring system was 0.695 (sensitivity 0.772, specificity 0.923) and was the highest among the five scoring systems. Conclusions: SF shows well predictive efficiency for IVIGRKD and is an independent risk factor for IVIGRKD. SF can be used as a new predictor of IVIGRKD.

[Sensitivity and specificity of nucleic acid testing in close contacts of COVID-19 cases in Guangzhou]

Objective: To analyze the sensitivity and specificity of SARS-CoV-2 nucleic acid testing in 20 348 close contacts of COVID-19 cases in different prevention and control stages in Guangzhou and to provide scientific evidence for optimizing epidemic response strategies. Methods: A total of 20 348 close contacts of COVID-19 cases in Guangzhou were traced between February 21 and September 22,2020. All the close contacts were tested for the nucleic acid of SARS-CoV-2. The sensitivity and specificity of nucleic acid testing and diagnosis in the different prevention and control stages were compared. Results: In 20 348 close contacts, 12 462 were males (61.24%), the median (P₂₅,P₇₅) of age of them was 31.0 years (23.0,43.0), the median number (P₂₅,P₇₅) of nucleic acid testing for them was 2.0 (1.0,3.0), and the median (P₂₅,P₇₅) of their quarantine days was 12.0 (8.0,13.0) days, respectively. A total of 256 COVID-19 cases were confirmed in the close contacts after seven nucleic acid tests. In the 1^st, 2^nd, 3^rd and 7^th nucleic acid testing, the sensitivity and specificity were 69.14% and 99.99% (177 cases confirmed), 89.84% and 99.99% (230 cases confirmed), 97.27% and 99.99% (249 cases confirmed), and 100.00% and 99.98%, respectively. In the three stages of COVID-19 prevention and control in China: domestic case stage, imported case stage, and imported case associated local epidemic stage, the sensitivity of the 1^st nucleic acid testing was 70.68%, 68.00% and 67.35%, and the specificity was 99.98%, 100.00% and 100.00%, respectively. Conclusions: The sensitivity of nucleic acid testing in the close contacts at the different stages were consistent with slight decrease, which might be related to the increased proportion of asymptomatic infections in the late stage of epidemic prevention and control with COVID-19 in Guangzhou. It is suggested to give three nucleic acid tests to improve the sensitivity and reduce false negative risk.

[The relationship between resting heart rate and all-cause mortality among the Chinese oldest-old aged more than 80: a prospective cohort study]

Objective: To explore the association between resting heart rate(RHR) and all-cause mortality among the Chinese oldest-old aged more than 80. Methods: Using a total of seven surveys or follow-ups data (1998, 2000, 2002, 2005, 2008, 2011 and 2014) from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 17 886 elderly over 80 years old were selected as subjects, their resting heart rate were measured though baseline survey and the survival outcome and death time of the subjects were followed up. The subjects were divided into 6 groups according to their resting heart rate. Cox regression model was used to estimate the effect of resting heart rate on mortality risk. The interaction of age, gender and resting heart rate was also analyzed by likelihood ratio test. Results: The age of subjects M (P₂₅, P₇₅) was 92 (86, 100) years old, including 10 531 females (58.9%) and there were 13 598 participants died, the mortality rate was 195.5 per 1 000 person-years. Multivariate Cox regression analysis showed that compared to the control group (60-69 pbm/min), the hazard ratio of the elderly are 1.06 (95%CI: 1.02, 1.11), 1.09 (95%CI: 1.04, 1.15), 1.23 (95%CI: 1.14, 1.34), 1.25 (95%CI: 1.08, 1.44) in the group of RHR between 70-79, 80-89, 90-99 and ≥100 pbm/min and P values are all less than 0.05. Likelihood ratio test showed that RHR and age had an interaction effect. (P for interaction=0.011). Conclusion: The risk of all-cause death increased with the increase of resting heart rate and this relationship was stronger between the 80-89 years old people.

Development and Evaluation of Vero Cell-Derived Master Donor Viruses for Influenza Pandemic Preparedness

The embryonated egg-based platform currently produces the majority of seasonal influenza vaccines by employing a well-developed master donor virus (MDV, A/PR/8/34 (PR8)) to generate high-growth reassortants (HGRs) for A/H1N1 and A/H3N2 subtypes. Although the egg-based platform can supply enough seasonal influenza vaccines, it cannot meet surging demands during influenza pandemics. Therefore, multi-purpose platforms are desirable for pandemic preparedness. The Vero cell-based production platform is widely used for human vaccines and could be a potential multi-purpose platform for pandemic influenza vaccines. However, many wild-type and egg-derived influenza viruses cannot grow efficiently in Vero cells. Therefore, it is critical to develop Vero cell-derived high-growth MDVs for pandemic preparedness. In this study, we evaluated two in-house MDVs (Vero-15 and VB5) and two external MDVs (PR8 and PR8-HY) to generate Vero cell-derived HGRs for five avian influenza viruses (AIVs) with pandemic potentials (H5N1 clade 2.3.4, H5N1 clade 2.3.2.1, American-lineage H5N2, H7N9 first wave and H7N9 fifth wave). Overall, no single MDV could generate HGRs for all five AIVs, but this goal could be achieved by employing two in-house MDVs (vB5 and Vero-15). In immunization studies, mice received two doses of Vero cell-derived inactivated H5N1 and H7N9 whole virus antigens adjuvanted with alum and developed robust antibody responses.

[Significance of microRNA 216a, 324-5p and 29a expression in peripheral blood in patients with acute pancreatitis and their correlation with liver injury]

Objective: To investigate the significance of microRNA (miR)-216a, miR-324-5p, miR-29a expression in peripheral blood in patients with acute pancreatitis (AP) and their correlation with liver injury. Methods: It was a case-control study design. To select 130 AP patients admitted from June 2017 to May 2019 in the First People's Hospital of Shangqiu, and the patients were divided into mild AP group (MAP group) and moderately severe AP group (SAP group) according to the disease severity, or 54 patients in the liver injury group (20 were MAP and 34 were SAP) and 76 in the non-liver injury group(all were MAP) according to liver injury. And another 40 healthy volunteers were selected as the healthy group. The expressions of miR-216a, miR-324-5p and miR-29a in peripheral blood of MAP group, SAP group, healthy group and liver injury group, non-liver injury group were compared, and the correlation between the miRNA levels and clinical indexes was analyzed. The predictive value of miRNA levels in peripheral blood for AP complicated with liver injury was analyzed by receiver operating characteristic (ROC) curve. Results: The levels of miR-216a and miR-29a in MAP group and SAP group were higher than those in healthy group, and the level of miR-324-5p was lower than that in healthy group (all P<0.01). The levels of miR-216a and miR-29a in SAP group were higher than those in MAP group, and the level of miR-324-5p was lower than that in healthy group (all P<0.01). Balthazar CT Score, acute physiology and chronic health evaluations (APACHE Ⅱ) score, C-reactive protein level, length of hospital stay were positively correlated with the levels of miR-216a and miR-29a in peripheral blood (all P<0.05), and negatively correlated with the levels of miR-324-5p (P<0.05). The levels of miR-216a and miR-29a in the peripheral blood in the liver injury group were higher than those in the non-liver injury group, and they were higher inSAP patients than those in MAP patients in the liver injury group (all P<0.05). The level of miR-324-5p in the peripheral blood in the liver injury group was lower than that in the non-liver injury group, and it was lower in SAP patients than that in MAP patientsin the liver injury group (all P<0.05). The area under ROC curve of miR-216a, miR-324-5p, and miR-29a in peripheral blood to predicate the AP complicated with liver damage was 0.694, 0.750 and 0.814, respectively. Conclusions: The levels of miR-216a and miR-29a increase in peripheral blood and the level of miR-324-5p decreases in patients with AP, and they are closely related to Balthazar CT score, APACHEⅡ score, C-reactive protein and length of hospital stay. The levels of miR-216a, miR-324-5p, miR-29a has certain predictive value for AP with liver injury, of which miR-29a has the highest predictive value.

Development of high-growth influenza H7N9 prepandemic candidate vaccine viruses in suspension MDCK cells

BACKGROUND

Influenza vaccine manufacturers traditionally use egg-derived candidate vaccine viruses (CVVs) to produce high-yield influenza viruses for seasonal or pandemic vaccines; however, these egg-derived CVVs need an adaptation process for the virus to grow in mammalian cells. The low yields of cell-based manufacturing systems using egg-derived CVVs remain an unsolved issue. This study aimed to develop high-growth cell-derived CVVs for MDCK cell-based vaccine manufacturing platforms.

METHODS

Four H7N9 CVVs were generated in characterized Vero and adherent MDCK (aMDCK) cells. Furthermore, reassortant viruses were amplified in adherent MDCK (aMDCK) cells with certification, and their growth characteristics were detected in aMDCK cells and new suspension MDCK (sMDCK) cells. Finally, the plaque-forming ability, biosafety, and immunogenicity of H7N9 reassortant viruses were evaluated.

RESULTS

The HA titers of these CVVs produced in proprietary suspension MDCK (sMDCK) cells and chicken embryos were 2- to 8-fold higher than those in aMDCK cells. All H7N9 CVVs showed attenuated characteristics by trypsin-dependent plaque assay and chicken embryo lethality test. The alum-adjuvanted NHRI-RG5 (derived from the fifth wave H7N9 virus A/Guangdong/SP440/2017) vaccine had the highest immunogenicity and cross-reactivity among the four H7N9 CVVs. Finally, we found that AddaVax adjuvant improved the cross-reactivity of low pathogenic H7N9 virus against highly pathogenic H7N9 viruses.

CONCLUSIONS

Our study indicates that cell-derived H7N9 CVVs possessed high growth rate in new sMDCK cells and low pathogenicity in chicken embryo, and that CVVs generated by this platform are also suitable for both cell- and egg-based prepandemic vaccine production.

The efficacy and safety of topical rapamycin-calcitriol for facial angiofibromas in patients with tuberous sclerosis complex: a prospective, double-blind, randomized clinical trial

BACKGROUND

The efficacy of topical rapamycin is well documented for tuberous sclerosis complex (TSC)-related facial angiofibromas (FAs). Calcitriol has been shown to lessen skin fibrosis and may be therapeutically beneficial to FAs.

OBJECTIVES

To evaluate whether topical rapamycin-calcitriol combination is an effective and safe treatment for TSC-related FAs.

METHODS

Fifty-two patients with TSC with FAs were enrolled in this prospective study including three 12-week periods. In period 1, either topical rapamycin 0·1% or calcitriol 0·0003% single-agent therapy vs. their combination was applied in a double-blind, left-right-randomized, split-face comparison. The primary outcome was the reduction of modified Facial Angiofibroma Severity Index (mFASI) at week 12. In period 2, the patients were reassigned to use on both cheeks the ointment that resulted in the better primary outcome in period 1. The treatment was discontinued in period 3 (week 25-36) and a follow-up mFASI was scored to evaluate the degree of recurrence.

RESULTS

The mean changes in mFASI at week 12 compared with baseline were -0·92, -0·44 and -1·09 for rapamycin (P ≤ 0·001), calcitriol (P = 0·039) and rapamycin-calcitriol combination (P ≤ 0·001), respectively. Although rapamycin-calcitriol combination and rapamycin had similar statistically significant decreases of mFASI at week 12, rapamycin-calcitriol combination resulted in faster improvement in erythema, greater reduction of papule elevation and longer durability after discontinuing treatment than rapamycin alone. The treatments were well tolerated.

CONCLUSIONS

This randomized clinical trial demonstrates that topical rapamycin-calcitriol combination therapy is an effective and safe regimen for TSC-related FAs. What is already known about this topic? Facial angiofibromas (FAs) cause substantial psychological distress in individuals with tuberous sclerosis complex (TSC), but invasive procedural treatments are not applicable to all patients. Topical rapamycin has been demonstrated as an effective and safe treatment regimen for TSC-related FAs. What does this study add? Compared with baseline (day 0), both topical rapamycin 0·1% and rapamycin 0·1%-calcitriol 0·0003% combination ointment achieved statistically significant reductions in modified Facial Angiofibroma Severity Index at week 12. Compared with rapamycin alone, extended use of the rapamycin-calcitriol combination regimen until week 24 showed more effectiveness in decreasing papule elevation and could maintain a longer therapeutic effect after treatment discontinuation. Linked Comment: Lee. Br J Dermatol 2020; 183:604-606.

Development and characterization of standard reagents for cell-based prepandemic influenza vaccine products

Outbreaks of infection by novel avian influenza virus strains in humans cause public health issues worldwide, and the development of vaccines against such novel strains is the most effective method for the prevention of these virus outbreaks. All types of vaccines must be tested for potency before use; thus, quantitative potency assays are needed for influenza vaccines. The single radial immunodiffusion (SRID) assay is considered the gold standard for quantification of influenza virus antigens, and the SRID reference reagents are essential for the determination of vaccine potency. However, it remains debatable whether reference reagents derived from egg-based vaccine platforms can be used to precisely quantify non-egg-derived vaccines; thus, influenza vaccine production using cell-based platforms has attracted increasing attention. To evaluate the utility of reference reagents derived from a cell-based influenza vaccine platform, we prepared cell-based reference reagents from MDCK cell-grown viruses and compared them with egg-derived reference reagents. A primary liquid standard (PLS) was purified from cell-derived candidate influenza vaccine viruses, and hemagglutinin (HA) antigen content was determined by a densitometric method. The produced PLS could be stored at 4°C for more than 10 months. We also established a simple HA protein purification method for goat antiserum preparation, and the performance of the resulting antiserum was compared to that of standard reagents obtained using different production platforms. The results of this study indicate that these reference reagents can be used for both cell-based and egg-based production platforms and that the differences between these two types of platforms are negligible.

Development of American-Lineage Influenza H5N2 Reassortant Vaccine Viruses for Pandemic Preparedness

Novel low-pathogenic avian influenza (LPAI) H5N2 viruses hit poultry farms in Taiwan in 2003, and evolved into highly pathogenic avian influenza (HPAI) viruses in 2010. These viruses are reassortant viruses containing HA and NA genes from American-lineage H5N2 and six internal genes from local H6N1 viruses. According to a serological survey, the Taiwan H5N2 viruses can cause asymptomatic infections in poultry workers. Therefore, a development of influenza H5N2 vaccines is desirable for pandemic preparation. In this study, we employed reverse genetics to generate a vaccine virus having HA and NA genes from A/Chicken/CY/A2628/2012 (E7, LPAI) and six internal genes from a Vero cell-adapted high-growth H5N1 vaccine virus (Vero-15). The reassortant H5N2 vaccine virus, E7-V15, presented high-growth efficiency in Vero cells (512 HAU, 10^7.6 TCID₅₀/mL), and passed all tests for qualification of candidate vaccine viruses. In ferret immunization, two doses of inactivated whole virus antigens (3 μg of HA protein) adjuvanted with alum could induce robust antibody response (HI titre 113.14). In conclusion, we have established reverse genetics to generate a qualified reassortant H5N2 vaccine virus for further development.

Precision Measurement of the Branching Fractions of η^{'} Decays

Based on a sample of (1310.6±7.0)×10^{6}J/ψ events collected with the BESIII detector, we present measurements of J/ψ and η^{'} absolute branching fractions using the process J/ψ→γη^{'}. By analyzing events where the radiative photon converts into an e^{+}e^{-} pair, the branching fraction for J/ψ→γη^{'} is measured to be (5.27±0.03±0.05)×10^{-3}. The absolute branching fractions of the five dominant decay channels of the η^{'} are then measured for the first time and are determined to be B(η^{'}→γπ^{+}π^{-})=(29.90±0.03±0.55)%, B(η^{'}→ηπ^{+}π^{-})=(41.24±0.08±1.24)%, B(η^{'}→ηπ^{0}π^{0})=(21.36±0.10±0.92)%, B(η^{'}→γω)=(2.489±0.018±0.074)%, and B(η^{'}→γγ)=(2.331±0.012±0.035)%, where the first uncertainties are statistical and the second systematic.

Measurement of the Dynamics of the Decays D_{s}^{+}→η^{(')}e^{+}ν_{e}

Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 3.19  fb^{-1} collected at a center-of-mass energy of 4.178 GeV with the BESIII detector, we measure the absolute branching fractions B_{D_{s}^{+}→ηe^{+}ν_{e}}=(2.323±0.063_{stat}±0.063_{syst})% and B_{D_{s}^{+}→η^{'}e^{+}ν_{e}}=(0.824±0.073_{stat}±0.027_{syst})% via a tagged analysis technique, where one D_{s} is fully reconstructed in a hadronic mode. Combining these measurements with previous BESIII measurements of B_{D^{+}→η^{(')}e^{+}ν_{e}}, the η-η^{'} mixing angle in the quark flavor basis is determined to be ϕ_{P}=(40.1±2.1_{stat}±0.7_{syst})°. From the first measurements of the dynamics of D_{s}^{+}→η^{(')}e^{+}ν_{e} decays, the products of the hadronic form factors f_{+}^{η^{(')}}(0) and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined with different form factor parametrizations. For the two-parameter series expansion, the results are f_{+}^{η}(0)|V_{cs}|=0.4455±0.0053_{stat}±0.0044_{syst} and f_{+}^{η^{'}}(0)|V_{cs}|=0.477±0.049_{stat}±0.011_{syst}.

Evidence of a Resonant Structure in the e^{+}e^{-}→π^{+}D^{0}D^{*-} Cross Section between 4.05 and 4.60 GeV

The cross section of the process e^{+}e^{-}→π^{+}D^{0}D^{*-} for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6±4.1±6.3  MeV/c^{2} and a width of 77.0±6.8±6.3  MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a DD[over ¯]_{1}(2420) molecule. This result is the first observation of Y(4220) associated with an open-charm final state. Fits with three resonance functions with additional Y(4260), Y(4320), Y(4360), ψ(4415), or a new resonance do not show significant contributions from either of these resonances. The second enhancement is not from a single known resonance. It could contain contributions from ψ(4415) and other resonances, and a detailed amplitude analysis is required to better understand this enhancement.

Determination of the Pseudoscalar Decay Constant f_{D_{s}^{+}} via D_{s}^{+}→μ^{+}ν_{μ}

Using a 3.19  fb^{-1} data sample collected at an e^{+}e^{-} center-of-mass energy of E_{cm}=4.178  GeV with the BESIII detector, we measure the branching fraction of the leptonic decay D_{s}^{+}→μ^{+}ν_{μ} to be B_{D_{s}^{+}→μ^{+}ν_{μ}}=(5.49±0.16_{stat}±0.15_{syst})×10^{-3}. Combining our branching fraction with the masses of the D_{s}^{+} and μ^{+} and the lifetime of the D_{s}^{+}, we determine f_{D_{s}^{+}}|V_{cs}|=246.2±3.6_{stat}±3.5_{syst}  MeV. Using the c→s quark mixing matrix element |V_{cs}| determined from a global standard model fit, we evaluate the D_{s}^{+} decay constant f_{D_{s}^{+}}=252.9±3.7_{stat}±3.6_{syst}  MeV. Alternatively, using the value of f_{D_{s}^{+}} calculated by lattice quantum chromodynamics, we find |V_{cs}|=0.985±0.014_{stat}±0.014_{syst}. These values of B_{D_{s}^{+}→μ^{+}ν_{μ}}, f_{D_{s}^{+}}|V_{cs}|, f_{D_{s}^{+}} and |V_{cs}| are each the most precise results to date.

First Measurement of the Form Factors in D_{s}^{+}→K^{0}e^{+}ν_{e} and D_{s}^{+}→K^{*0}e^{+}ν_{e} Decays

We report on new measurements of Cabibbo-suppressed semileptonic D_{s}^{+} decays using 3.19  fb^{-1} of e^{+}e^{-} annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(D_{s}^{+}→K^{0}e^{+}ν_{e})=[3.25±0.38(stat)±0.16(syst)]×10^{-3} and B(D_{s}^{+}→K^{*0}e^{+}ν_{e})=[2.37±0.26(stat)±0.20(syst)]×10^{-3}, which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For D_{s}^{+}→K^{0}e^{+}ν_{e}, we obtain f_{+}(0)=0.720±0.084(stat)±0.013(syst), and for D_{s}^{+}→K^{*0}e^{+}ν_{e}, we find form-factor ratios r_{V}=V(0)/A_{1}(0)=1.67±0.34(stat)±0.16(syst) and r_{2}=A_{2}(0)/A_{1}(0)=0.77±0.28(stat)±0.07(syst).

Observation of D^{+}→f_{0}(500)e^{+}ν_{e} and Improved Measurements of D→ρe^{+}ν_{e}

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D^{0}→π^{-}π^{0}e^{+}ν_{e} and D^{+}→π^{-}π^{+}e^{+}ν_{e}. By performing a partial wave analysis, the π^{+}π^{-} S-wave contribution to D^{+}→π^{-}π^{+}e^{+}ν_{e} is observed to be (25.7±1.6±1.1)% with a statistical significance greater than 10σ, besides the dominant P-wave contribution. This is the first observation of the S-wave contribution. We measure the branching fractions B(D^{0}→ρ^{-}e^{+}ν_{e})=(1.445±0.058±0.039)×10^{-3}, B(D^{+}→ρ^{0}e^{+}ν_{e})=(1.860±0.070±0.061)×10^{-3}, and B(D^{+}→f_{0}(500)e^{+}ν_{e},f_{0}(500)→π^{+}π^{-})=(6.30±0.43±0.32)×10^{-4}. An upper limit of B(D^{+}→f_{0}(980)e^{+}ν_{e},f_{0}(980)→π^{+}π^{-})<2.8×10^{-5} is set at the 90% confidence level. We also obtain the hadronic form factor ratios of D→ρe^{+}ν_{e} at q^{2}=0 assuming the single-pole dominance parametrization: r_{V}={[V(0)]/[A_{1}(0)]}=1.695±0.083±0.051, r_{2}={[A_{2}(0)]/[A_{1}(0)]}=0.845±0.056±0.039.

Study of the D^{0}→K^{-}μ^{+}ν_{μ} Dynamics and Test of Lepton Flavor Universality with D^{0}→K^{-}ℓ^{+}ν_{ℓ} Decays

Using e^{+}e^{-} annihilation data of 2.93  fb^{-1} collected at center-of-mass energy sqrt[s]=3.773  GeV with the BESIII detector, we measure the absolute branching fraction of D^{0}→K^{-}μ^{+}ν_{μ} with significantly improved precision: B_{D^{0}→K^{-}μ^{+}ν_{μ}}=(3.413±0.019_{stat}±0.035_{syst})%. Combining with our previous measurement of B_{D^{0}→K^{-}e^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{0}→K^{-}μ^{+}ν_{μ}}/B_{D^{0}→K^{-}e^{+}ν_{e}}=0.974±0.007_{stat}±0.012_{syst}, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. A study of the ratio of the two branching fractions in different four-momentum transfer regions is also performed, and no evidence for lepton flavor universality violation is found with current statistics. Taking inputs from global fit in the standard model and lattice quantum chromodynamics separately, we determine f_{+}^{K}(0)=0.7327±0.0039_{stat}±0.0030_{syst} and |V_{cs}|=0.955±0.005_{stat}±0.004_{syst}±0.024_{LQCD}.

Measurement of the Absolute Branching Fraction of the Inclusive Semileptonic Λ_{c}^{+} Decay

Using a data sample of e^{+}e^{-} collisions corresponding to an integrated luminosity of 567  pb^{-1} collected at a center-of-mass energy of sqrt[s]=4.6  GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive semileptonic Λ_{c}^{+} decay with a double-tag method. We obtain B(Λ_{c}^{+}→Xe^{+}ν_{e})=(3.95±0.34±0.09)%, where the first uncertainty is statistical and the second systematic. Using the known Λ_{c}^{+} lifetime and the charge-averaged semileptonic decay width of nonstrange charmed mesons (D^{0} and D^{+}), we obtain the ratio of the inclusive semileptonic decay widths Γ(Λ_{c}^{+}→Xe^{+}ν_{e})/Γ[over ¯](D→Xe^{+}ν_{e})=1.26±0.12.

Measurement of the Branching Fraction For the Semileptonic Decay D^{0(+)}→π^{-(0)}μ^{+}ν_{μ} and Test of Lepton Flavor Universality

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we perform an analysis of the semileptonic decays D^{0(+)}→π^{-(0)}μ^{+}ν_{μ}. The branching fractions of D^{0}→π^{-}μ^{+}ν_{μ} and D^{+}→π^{0}μ^{+}ν_{μ} are measured to be (0.272±0.008_{stat}±0.006_{syst})% and (0.350±0.011_{stat}±0.010_{syst})%, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of D^{0(+)}→π^{-(0)}e^{+}ν_{e}, we calculate the branching fraction ratios to be R^{0}≡B_{D^{0}→π^{-}μ^{+}ν_{μ}}/B_{D^{0}→π^{-}e^{+}ν_{e}}=0.922±0.030_{stat}±0.022_{syst} and R^{+}≡B_{D^{+}→π^{0}μ^{+}ν_{μ}}/B_{D^{+}→π^{0}e^{+}ν_{e}}=0.964±0.037_{stat}±0.026_{syst}, which are compatible with the theoretical expectation of lepton flavor universality within 1.7σ and 0.5σ, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.

Measurement of the Absolute Branching Fraction of the Inclusive Decay Λ_{c}^{+}→Λ+X

Based on an e^{+}e^{-} collision data sample corresponding to an integrated luminosity of 567  pb^{-1} taken at the center-of-mass energy of sqrt[s]=4.6  GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive decay Λ_{c}^{+}→Λ+X to be B(Λ_{c}^{+}→Λ+X)=(38.2_{-2.2}^{+2.8}±0.9)% using the double-tag method, where X refers to any possible final state particles. In addition, we search for direct CP violation in the charge asymmetry of this inclusive decay for the first time, and obtain A_{CP}≡[B(Λ_{c}^{+}→Λ+X)-B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]/[B(Λ_{c}^{+}→Λ+X)+B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]=(2.1_{-6.6}^{+7.0}±1.6)%, a statistically limited result with no evidence of CP violation.

Precision Measurement of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Cross Section Near Threshold

The cross section of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} process is measured with unprecedented precision using data collected with the BESIII detector at sqrt[s]=4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold is cleared. At center-of-mass energies sqrt[s]=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ_{c} polar angle distributions. From these, the Λ_{c} electric over magnetic form-factor ratios (|G_{E}/G_{M}|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03, respectively, where the first uncertainties are statistical and the second are systematic.

Gut microbiome modulates response to anti-PD-1 immunotherapy in melanoma patients

Preclinical mouse models suggest that the gut microbiome modulates tumor response to checkpoint blockade immunotherapy; however, this has not been well-characterized in human cancer patients. Here we examined the oral and gut microbiome of melanoma patients undergoing anti-programmed cell death 1 protein (PD-1) immunotherapy (n = 112). Significant differences were observed in the diversity and composition of the patient gut microbiome of responders versus nonresponders. Analysis of patient fecal microbiome samples (n = 43, 30 responders, 13 nonresponders) showed significantly higher alpha diversity (P < 0.01) and relative abundance of bacteria of the Ruminococcaceae family (P < 0.01) in responding patients. Metagenomic studies revealed functional differences in gut bacteria in responders, including enrichment of anabolic pathways. Immune profiling suggested enhanced systemic and antitumor immunity in responding patients with a favorable gut microbiome as well as in germ-free mice receiving fecal transplants from responding patients. Together, these data have important implications for the treatment of melanoma patients with immune checkpoint inhibitors.

Assessment of pathogenicity and antigenicity of American lineage influenza H5N2 viruses in Taiwan

During December 2003 and March 2004, large scale epidemics of low-pathogenic avian influenza (LPAI) H5N2 occurred in poultry farms in central and southern Taiwan. Based on genomic analysis, these H5N2 viruses contain HA and NA genes of American-lineage H5N2 viruses and six internal genes from avian influenza A/H6N1 viruses endemic in poultry in Taiwan. After disappearing for several years, these novel influenza H5N2 viruses caused outbreaks in poultry farms again in 2008, 2010 and 2012, and have evolved into high pathogenic AI (HPAI) since 2010. Moreover, asymptomatic infections of influenza H5N2 were detected serologically in poultry workers in 2012. Therefore, we evaluated antigenicity and pathogenicity of the novel H5N2 viruses in ferrets. We found that no significant antigenic difference was detected among the novel H5N2 viruses isolated from 2003 to 2014 and the novel H5N2 viruses could cause mild infections in ferrets. Monitoring zoonotic transmission of the novel H5N2 viruses is necessary.

A Novel Hybrid Viabahn-assisted Bypass Technique: Extra-arterial Flossing Wiring for Chronic Total Occlusion in Superficial Femoral Artery

Introduction

A hybrid Viabahn-assisted bypass (VAB) technique is introduced for revascularizing chronic total occlusion (CTO) in superficial femoral artery (SFA) when bypass surgery is difficult or endovascular intervention fails.

Report

This technique combines extra-arterial flossing wiring with antegrade-retrograde intervention via traditional open exposure of middle SFA and deploying a Viabahn from the proximal true lumen through the subintimal lumen and extra-arterial space, and back into distal true lumen to restore flow. It only needs a 3–5 cm incision to expose the mid-SFA without clamping or endarterectomy of the SFA.

Discussion

This hybrid procedure is an alternative technique to improve SFA revascularization in some difficult CTOs.

Association between MTHFR gene polymorphisms (C677T, A1298C) and genetic susceptibility to prostate cancer: a meta-analysis

Genetic polymorphisms (C677T and A1298C) in methylenetetrahydrofolate reductase (MTHFR) were shown to be related to prostate cancer risk in previous studies; however, the results are controversial. We performed a meta-analysis of previous studies and quantitatively estimated these associations. Pubmed, Embase, and Cochrane Library Database were searched for published case-control studies evaluating the association between C677T (or A1298C) and prostate cancer risk. Pooled associations were presented as odds ratios (ORs) along with their 95% confidence intervals. Twenty-one case control studies were identified for meta-analysis that included 21,581 participants. No significant associations were found between the MTHFR polymorphisms C677T or A1298C and prostate cancer risk in our meta-analysis. However, in subgroup analyses, the C677T CT polymorphism was associated with increased prostate cancer risk in East Asians (CT vs CC+TT: OR = 1.324, P = 0.03). The A1298C CC polymorphism in MTHFR was also linked to slightly reduced prostate cancer risk in European residents (CC vs AC+AA: OR = 0.751, P = 0.004; CC vs AA: OR = 0.768, P = 0.011), whereas it was associated with a significantly increased prostate cancer risk in Asian residents (CC vs AA: OR = 1.862, P = 0.006). The C677T CT polymorphism of MTHFR may be a risk factor for prostate cancer in East Asians. The association between the MTHFR A1298C CC genotype and prostate cancer risk may vary within different populations. Large-scale well-designed studies are required to confirm these associations.

Evaluation of MDCK cell-derived influenza H7N9 vaccine candidates in ferrets

Avian-origin influenza A (H7N9) viruses emerged as human pathogens in China in early 2013 and have killed >100 persons. Influenza vaccines are mainly manufactured using egg-based technology which could not meet the surging demand during influenza pandemics. In this study, we evaluated cell-based influenza H7N9 vaccines in ferrets. An egg-derived influenza H7N9 reassortant vaccine virus was adapted in MDCK cells. Influenza H7N9 whole virus vaccine antigen was manufactured using a microcarrier-based culture system. Immunogenicity and protection of the vaccine candidates with three different formulations (300μg aluminum hydroxide, 1.5μg HA, and 1.5μg HA plus 300μg aluminum hydroxide) were evaluated in ferrets. In ferrets receiving two doses of vaccination, geometric mean titers of hemagglutination (HA) inhibition and neutralizing antibodies were <10 and <40 for the control group (adjuvant only), 17 and 80 for the unadjuvanted (HA only) group, and 190 and 640 for the adjuvanted group (HA plus adjuvant), respectively. After challenge with wild-type influenza H7N9 viruses, virus titers in respiratory tracts of the adjuvanted group were significantly lower than that in the control, and unadjuvanted groups. MDCK cell-derived influenza H7N9 whole virus vaccine candidate is immunogenic and protective in ferrets and clinical development is highly warranted.

Detection of human JCPyV and BKPyV in diffuse large B-cell lymphoma of the GI tract

Previous studies have demonstrated that infection with human polyomavirus, such as JCPyV and BKPyV, might be associated with various human tumors. However, an association between human JCPyV and BKPyV infection and diffuse large B-cell lymphoma (DLBCL) has not been reported. The purpose of this study was to examine DLBCLs of the gastrointestinal tract for evidence of human polyomavirus infection. Nested PCR and DNA sequencing were employed for viral DNA detection and viral genotype identification. In addition, two viral proteins, the large tumor antigen (LT) and the major structural protein (VP1), were detected by immunohistochemistry (IHC). Human JCPyV and BKPyV DNA was detected in 14 out of 16 tissue samples (87.5%), whereby nine cases were infected with JCPyV and five cases were infected with BKPyV. Both archetypal and rearranged genotypes of JCPyV and BKPyV were detected in the tissues. LT was detected in 11 tissue samples (68.75%). However, VP1 was not detected in any of the tissue samples. The presence of human JCPyV and BKPyV DNA and protein in DLBCL tissues of gastrointestinal tract were first reported in this study. The current results provide evidence of a possible association between human JCPyV and BKPyV infection and DLBCL.

Detection of human JCPyV and BKPyV in diffuse large B-cell lymphoma of the GI tract

Previous studies have demonstrated that infection with human polyomavirus, such as JCPyV and BKPyV, might be associated with various human tumors. However, an association between human JCPyV and BKPyV infection and diffuse large B-cell lymphoma (DLBCL) has not been reported. The purpose of this study was to examine DLBCLs of the gastrointestinal tract for evidence of human polyomavirus infection. Nested PCR and DNA sequencing were employed for viral DNA detection and viral genotype identification. In addition, two viral proteins, the large tumor antigen (LT) and the major structural protein (VP1), were detected by immunohistochemistry (IHC). Human JCPyV and BKPyV DNA was detected in 14 out of 16 tissue samples (87.5%), whereby nine cases were infected with JCPyV and five cases were infected with BKPyV. Both archetypal and rearranged genotypes of JCPyV and BKPyV were detected in the tissues. LT was detected in 11 tissue samples (68.75%). However, VP1 was not detected in any of the tissue samples. The presence of human JCPyV and BKPyV DNA and protein in DLBCL tissues of gastrointestinal tract were first reported in this study. The current results provide evidence of a possible association between human JCPyV and BKPyV infection and DLBCL.

Enzymatic stability and immunoregulatory efficacy of a synthetic indolicidin analogue with regular enantiomeric sequence

Cell-mediated immunity plays a major role in protecting the host from viral infections and tumor challenge. Here, we report the enzymatic stability and adjuvanticity of a peptiomimetic stereoisomer of the bovine neutrophil peptide indolicidin. The analogue, dubbed ld-indolicidin, contains the regular enantiomeric sequence of indolicidin and is synthesized by general stepwise solid-phase strategy. ld-Indolicidin possesses high resistance to enzymatic degradation and shows tolerance in mice. As vaccine adjuvant, ld-indolicidin is better able than the native form of indolicidin to enhance cell-mediated immune responses, using inactivated H5N1 virus as a model antigen. Taken together, these results open up a new approach to the development of vaccine adjuvants and immunotherapy technologies.

Transgenic expression of haem oxygenase-1 in pancreatic beta cells protects non-obese mice used as a model of diabetes from autoimmune destruction and prolongs graft survival following islet transplantation

AIMS/HYPOTHESIS

Haem oxygenase 1 (HO-1) has strong anti-apoptotic, anti-inflammatory and antioxidative effects that help protect cells against various forms of immune attack. We investigated whether transgenic expression of Ho-1 (also known as Hmox1) in pancreatic beta cells would protect NOD mice from autoimmune damage and prolong graft survival following islet transplantation.

METHODS

To evaluate the protective effect of beta cell-specific HO-1 in autoimmune diabetes, we used an insulin promoter-driven murine Ho-1 construct (pIns-mHo-1) to generate a transgenic NOD mouse. Transgene expression, insulitis and the incidence of diabetes in mice were characterised. Lymphocyte composition, the development of T helper (Th)1, Th2 and T regulatory (Treg) cells, T cell proliferation and lymphocyte-mediated disease transfer were analysed. The potential effects of transgenic islets and islet transplantation on apoptosis, inflammation and the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) were evaluated.

RESULTS

Transgenic mice showed less severe insulitis and a lower incidence of diabetes than non-transgenic control littermates. Lymphocyte composition and functions were not affected. Islets from transgenic mice expressed lower levels of proinflammatory cytokines/chemokines, proapoptotic gene expression and amounts of ROS/RNS, and were more resistant to TNF-α- and IFN-γ-induced apoptosis. Islet grafts from transgenic mice also survived longer in diabetic recipients than control islets.

CONCLUSIONS/INTERPRETATION

Transgenic overexpression of Ho-1 in beta cells protected NOD mice from diabetes and delayed the autoimmune destruction of islet grafts, providing valuable insight into the development of better strategies for clinical islet transplantation in patients with type 1 diabetes.

Risk factors of multidrug resistance in nosocomial bacteremia due to Acinetobacter baumannii: a case-control study

BACKGROUND AND PURPOSE

Acinetobacter baumannii is an important nosocomial pathogen. Bacteremia caused by multidrug-resistant A. baumannii (MDRAB) leads to higher mortality and medical cost compared with non-MDRAB bacteremia. We aimed to identify risk factors of multidrug resistance in A. baumannii bacteremia.

METHODS

A matched case-control study was conducted to compare the differences in risk factors of patients with MDRAB and non-MDRAB bacteremia.

RESULTS

Sixty three patients with MDRAB bacteremia and 63 matched patients with non-MDRAB bacteremia were identified from hospital and laboratory records of the period 1996 to 2002. Multivariate logistic regression analysis identified four independent risk factors associated with multidrug resistance in A. baumannii bacteremic patients: previous colonization with A. baumannii (odds ratio [OR], 7.99; 95% confidence interval [CI], 2.1-30.6; p=0.002), antecedent antimicrobial therapy (OR, 6.10; 95% CI, 1.2-29.9; p=0.026) the number of recently prescribed antibiotics (OR 1.35; 95% CI, 1.0-1.8; p=0.026), and recent invasive procedures (OR, 4.17; 95% CI, 1.6-11.1; p=0.004).

CONCLUSIONS

Overall, patients with MDRAB bacteremia had earlier A. baumannii colonization, greater previous exposure to antimicrobial agents and recent invasive procedures. The results of this study demonstrate a rationale for the development of effective interventions to minimize the impact of MDRAB.

Changes of brachial flow-mediated vasodilation in different ischemic stroke subtypes

The relationship between endothelial dysfunction and stroke subtypes is unclear. We prospectively measured brachial flow-mediated vasodilation (FMD) in 143 patients with acute ischemic stroke and 40 controls. The overall stroke patients had impaired FMD, but only lacunar infarction had significantly impaired FMD vs the controls. Impaired FMD was an independent predictor for lacunar infarction. Ischemic stroke is associated with endothelial dysfunction, which is more conspicuous in lacunar infarction.

An atomic force microscope study of thermal behavior of phospholipid monolayers on mica

We observed by using atomic force microscope (AFM) phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) monolayers on mica being annealed and cooled to a selection of temperatures through steps of 2-4 degrees C/min. The annealed phospholipid monolayers started to disappear at 45-50 degrees C and disappeared completely above 60-63 degrees C under AFM observation. The phospholipid monolayers reformed when the samples were cooled below 60 degrees C and developed from fractal into compact monolayer films with decreasing temperatures. Simultaneously the height of the reformed phospholipid films also increased with decreasing temperatures from 0.4 nm to the value before annealing. The observed thermal features are attributed to a phase-transition process that upon heating to above 45-50 degrees C, the lipids condensed in the monolayers transform into a low-density expanded phase in which the lipids are invisible to AFM, and the transformation continues and completes at 60-63 degrees C. The lipid densities of the expanded phase inferred from the dissociated area of the condensed phase are observed to be a function of the temperature. The behavior contrasts with a conventional first-order phase transition commonly seen in the Langmuir films. The temperature-dependent height and shape of the reformed phospholipid films during cooling are argued to arise from the adjustment of the packing and molecular tilting (with respect to the mica surface) of the phospholipids in order to accommodate more condensed phospholipids.

Growth of Co clusters on thin films Al2O3∕NiAl(100)

We present a scanning tunnel microscopy study of Co clusters grown through vapor deposition on Al(2)O(3) thin films over NiAl(100) at different coverages and temperatures. Formation of Co clusters was observed at 90, 300, 450, and 570 K. At the three lower temperatures, we find narrow cluster size distributions and the mean sizes (with a diameter of 2.6 nm and a height of 0.7 nm) do not change significantly with the coverage and temperature, until the clusters start to coalesce. Even on 3-4-nm-wide crystalline Al(2)O(3) strips where the deposited Co atoms are confined, the same features sustain. Only at 570 K the normal growth mode where the cluster size increases with the deposition coverage is observed, although the data are less conclusive. A simple modeling of kinetic surface processes on a strip confirms the normal growth mode, but fails to show a favored size unless additional energetic constraints are applied on the cluster sizes. Increasing Co coverages to cluster coalescence, a larger preferable size (mean diameter of 3.5 nm and height of 1.4 nm) appears for growth at 450 K. These two sizes are corroborated by morphology evolution of high Co coverages deposited at 300 K and annealed to 750 K, in which the coalescence is eliminated and the two preferable geometries appear and coexist.

Non-clostridial gas gangrene caused by Klebsiella pneumoniae: a case report

A 45-y-old man was hospitalized due to pain and swelling of the right leg for 3 d. Bullae developed with gas formation involving multiple compartments of the entire limb 46 h later. Klebsiella pneumoniae was recovered from blood and surgical specimens. The patient died on Day 8 despite amputation and antibiotic therapy.

Quality-adjusted survival estimation with periodic observations

Quality-adjusted survival is a measure that integrates both longevity and quality-of-life information. The analysis of quality-adjusted survival in a clinical study with data collected at periodic intervals encounters difficulties due to incomplete information. Based on observed time points, the time axis is partitioned into a set of disjoint time intervals, and under a Markovian assumption on patient's health status, the expected quality-adjusted survival is estimated as the summed product of the quality of life and its mean sojourn time of each health state within partitioned intervals. It is shown that the estimator is asymptotically normal with a simple variance calculation. A simulation study is conducted to investigate the behavior of the estimator, and a stroke study illustrates the use of the estimator.

Disulfide bonds stabilize JC virus capsid-like structure by protecting calcium ions from chelation

To investigate the role of disulfide bonds in the capsid structure, a recombinant JC virus-like particle (VLP) was used. The major capsid protein, VP1, of the JC virus was expressed in yeast cells. The yeast-expressed VP1 was self-assembled into a VLP. Disulfide bonds were found in the VLP which caused dimeric and trimeric VP1 linkages as demonstrated by non-reducing SDS-PAGE. The VLP remained intact when disulfide bonds were reduced by dithiothreitol. The VLP without disulfide bonds could be disassembled into capsomeres by EGTA alone, but those with disulfide bonds could not be disassembled by EGTA. Capsomeres were reassembled into VLPs in the presence of calcium ions. Capsomeres formed irregular aggregations instead of VLPs when treated with diamide to reconstitute the disulfide bonds. These results indicate that disulfide bonds play an important role in maintaining the integrity of the JC VLP by protecting calcium ions from chelation.

Genome mining for human cancer genes: wherefore art thou?

In an initial data-mining effort, the draft human genome was searched to find paralogs of known tumor suppressor genes, and for gene arrangements, which are typical of oncogenes, in cancer cells. The results were disappointing, indicating that although knowledge of the human genome will undoubtedly be of great help, other approaches to identify new oncogenes are needed.

RINT-1, a novel Rad50-interacting protein, participates in radiation-induced G(2)/M checkpoint control

Rad50, an structural maintenance of chromosomes (SMC) protein family member, participates in a variety of cellular processes, including DNA double-strand break repair, cell cycle checkpoint activation, telomere maintenance, and meiosis. Disruption of Rad50 in mice leads to lethality during early embryogenesis, indicating its essential function in normal proliferating cells. In addition to its ability to form a complex with the DNA double-strand break repair proteins Mre11 and NBS1, Rad50 may interact with other cellular proteins to execute its full range of biological activities. A novel 87-kDa protein named RINT-1 was identified using the C-terminal region of human Rad50 as the bait in a yeast two-hybrid screen. Human RINT-1 shares sequence homology with a novel protein identified in Drosophila melanogaster, including a coiled-coil domain within its N-terminal 150 amino acids, a conserved central domain of about 350 amino acids, and a C-terminal region of 90 amino acids exhibiting 35--38% identity. The conserved central and C-terminal regions of RINT-1 are required for its interaction with Rad50. While Rad50 and RINT-1 are both expressed throughout the cell cycle, RINT-1 specifically binds to Rad50 only during late S and G(2)/M phases, suggesting that RINT-1 may be involved in cell cycle regulation. Consistent with this possibility, MCF-7 cells expressing an N-terminally truncated RINT-1 protein displayed a defective radiation-induced G(2)/M checkpoint. These results suggest that RINT-1 may play a role in the regulation of cell cycle control after DNA damage.

Sequence-specific transcriptional corepressor function for BRCA1 through a novel zinc finger protein, ZBRK1

BRCA1 has been implicated in the transcriptional regulation of DNA damage-inducible genes that function in cell cycle arrest. To explore the mechanistic basis for this regulation, a novel human gene, ZBRK1, which encodes a 60 kDa protein with an N-terminal KRAB domain and eight central zinc fingers, was identified by virtue of its interaction with BRCA1 in vitro and in vivo. ZBRK1 binds to a specific sequence, GGGxxx CAGxxxTTT, within GADD45 intron 3 that supports the assembly of a nuclear complex minimally containing both ZBRK1 and BRCA1. ZBRK1 represses transcription through this recognition sequence in a BRCA1-dependent manner. These results thus reveal a novel corepressor function for BRCA1 and provide a mechanistic basis for the biological activity of BRCA1 through sequence-specific transcriptional regulation.

NBS1 and TRF1 colocalize at promyelocytic leukemia bodies during late S/G2 phases in immortalized telomerase-negative cells. Implication of NBS1 in alternative lengthening of telomeres

Nijmegen breakage syndrome, a chromosomal instability disorder, is characterized in part by cellular hypersensitivity to ionizing radiation. The NBS1 gene product, p95 (NBS1 or nibrin) forms a complex with Rad50 and Mre11. Cells deficient in the formation of this complex are defective in DNA double-strand break repair, cell cycle checkpoint control, and telomere length maintenance. How the NBS1 complex is involved in telomere length maintenance remains unclear. Here we show that the C-terminal region of NBS1 interacts directly with a telomere repeat binding factor, TRF1, by both yeast two-hybrid and in vivo DNA-coimmunoprecipitation assays. NBS1 and Mre11 colocalize with TRF1 at promyelocytic leukemia (PML) nuclear bodies in immortalized telomerase-negative cell lines, but rarely in telomerase-positive cell lines. The translocation of NBS1 to PML bodies occurs specifically during late S to G(2) phases of the cell cycle and coincides with active DNA synthesis in these NBS1-containing PML bodies. These results suggest that NBS1 may be involved in alternative lengthening of telomeres in telomerase-negative immortalized cells.

Functional link of BRCA1 and ataxia telangiectasia gene product in DNA damage response

BRCA1 encodes a familial breast cancer suppressor that has a critical role in cellular responses to DNA damage. Mouse cells deficient for Brca1 show genetic instability, defective G2-M checkpoint control and reduced homologous recombination. BRCA1 also directly interacts with proteins of the DNA repair machinery and regulates expression of both the p21 and GADD45 genes. However, it remains unclear how DNA damage signals are transmitted to modulate the repair function of BRCA1. Here we show that the BRCA1-associated protein CtIP becomes hyperphosphorylated and dissociated from BRCA1 upon ionizing radiation. This phosphorylation event requires the protein kinase (ATM) that is mutated in the disease ataxia telangiectasia. ATM phosphorylates CtIP at serine residues 664 and 745, and mutation of these sites to alanine abrogates the dissociation of BRCA1 from CtIP, resulting in persistent repression of BRCA1-dependent induction of GADD45 upon ionizing radiation. We conclude that ATM, by phosphorylating CtIP upon ionizing radiation, may modulate BRCA1-mediated regulation of the DNA damage-response GADD45 gene, thus providing a potential link between ATM deficiency and breast cancer.