Quantification of biological age as a determinant of age-related diseases in the Rotterdam Study: a structural equation modeling approach.

Chronological age alone is not a sufficient measure of the true physiological state of the body. The aims of the present study were to: (1) quantify biological age based on a physiological biomarker composite model; (2) and evaluate its association with death and age-related disease onset in the setting of an elderly population. Using structural equation modeling we computed biological age for 1699 individuals recruited from the first and second waves of the Rotterdam study. The algorithm included nine physiological parameters (c-reactive protein, creatinine, albumin, total cholesterol, cytomegalovirus optical density, urea nitrogen, alkaline phosphatase, forced expiratory volume and systolic blood pressure). We assessed the association between biological age, all-cause mortality, all-cause morbidity and specific age-related diseases over a median follow-up of 11 years. Biological age, compared to chronological age or the traditional biomarkers of age-related diseases, showed a stronger association with all-cause mortality (HR 1.15 vs. 1.13 and 1.10), all-cause morbidity (HR 1.06 vs. 1.05 and 1.03), stroke (HR 1.17 vs. 1.08 and 1.04), cancer (HR 1.07 vs. 1.04 and 1.02) and diabetes mellitus (HR 1.12 vs. 1.01 and 0.98). Individuals who were biologically younger exhibited a healthier life-style as reflected in their lower BMI (P < 0.001) and lower incidence of stroke (P < 0.001), cancer (P < 0.01) and diabetes mellitus (P = 0.02). Collectively, our findings suggest that biological age based on the biomarker composite model of nine physiological parameters is a useful construct to assess individuals 65 years and older at increased risk for specific age-related diseases.

Predictive value of the pretreatment extent of disease system in hepatoblastoma: results from the International Society of Pediatric Oncology Liver Tumor Study Group SIOPEL-1 study.

PURPOSE: Preoperative staging (pretreatment extent of disease [PRETEXT]) was developed for the first prospective liver tumor study by the International Society of Pediatric Oncology (SIOPEL-1 study; preoperative chemotherapy and delayed surgery). Study aims were to analyze the accuracy and interobserver agreement of PRETEXT and to compare the predictive impact of three currently used staging systems. PATIENTS AND METHODS: Hepatoblastoma (HB) patients younger than 16 years who underwent surgical resection (128 of 154 patients) were analyzed. The centrally reviewed preoperative staging was compared with postoperative pathology (accuracy) in 91 patients (81%), and the local center staging was compared with the central review (interobserver agreement) in 97 patients (86%), using the agreement beyond change method (weighted kappa). The predictive values of the three staging systems were compared in 110 patients (97%) using survival curves and Cox proportional hazard ratio estimates. RESULTS: Preoperative PRETEXT staging compared with pathology was correct in 51%, overstaged in 37%, and understaged in 12% of patients (weighted kappa = 0.44; 95% CI, 0.26 to 0.62). The weighted kappa value of the interobserver agreement was 0.76 (95% CI, 0.64 to 0.88). The Children's Cancer Study Group/Pediatric Oncology Group-based staging system showed no predictive value for survival (P = .516), but the tumor-node-metastasis-based system and PRETEXT system showed good predictive values (P = .0021 and P = .0006, respectively). PRETEXT seemed to be superior in the statistical fit. CONCLUSION: PRETEXT has moderate accuracy with a tendency to overstage patients, shows good interobserver agreement (reproducibility), shows superior predictive value for survival, offers the opportunity to monitor the effect of preoperative therapy, and can also be applied in patients who have not had operations. For comparability reasons, we recommend that all HB patients included in trials also be staged according to PRETEXT.

Human monoclonal antibody as prophylaxis for SARS coronavirus infection in ferrets.

SARS coronavirus continues to cause sporadic cases of severe acute respiratory syndrome (SARS) in China. No active or passive immunoprophylaxis for disease induced by SARS coronavirus is available. We investigated prophylaxis of SARS coronavirus infection with a neutralising human monoclonal antibody in ferrets, which can be readily infected with the virus. Prophylactic administration of the monoclonal antibody at 10 mg/kg reduced replication of SARS coronavirus in the lungs of infected ferrets by 3.3 logs (95% CI 2.6-4.0 logs; p<0.001), completely prevented the development of SARS coronavirus-induced macroscopic lung pathology (p=0.013), and abolished shedding of virus in pharyngeal secretions. The data generated in this animal model show that administration of a human monoclonal antibody might offer a feasible and effective prophylaxis for the control of human SARS coronavirus infection.

TMC125 exerts similar initial antiviral potency as a five-drug, triple class antiretroviral regimen.

OBJECTIVE: TMC125, a next generation, non-nucleoside reverse transcriptase inhibitor (NNRTI), demonstrated a remarkable decline of plasma HIV-1 RNA during a phase IIa study. We compared the initial rate of decline of plasma HIV-1 RNA achieved by TMC125 monotherapy with that of a triple class, five-drug regimen, containing drugs from all three currently licensed classes (zidovudine, lamivudine, abacavir, indinavir and nevirapine). METHODS: The decline in plasma HIV-1 RNA of 12 HIV-1 infected, antiretroviral (ART) naive patients treated for 1 week with TMC125 monotherapy was compared with that observed in the ERA study (n = 11). The plasma HIV-1 RNA elimination rate constant was calculated based on at least four plasma HIV-1 RNA measurements during the first week of treatment (first-order elimination) and compared using the Student's t test. RESULTS: Median ages were 23 and 38 years for TMC125 and ERA patients, respectively (P = 0.001), median baseline plasma HIV-1 RNA levels were 4.2 and 4.8 log10 copies/ml (P = 0.001) and median baseline CD4 T-cell counts were 458 x 10(6) and 360 x 10(6) cells/l (P = 0.08). The median plasma HIV-1 RNA elimination rate constant was 0.68/day in TMC125 treated patients, and 0.56/day in ERA participants (P = 0.24). The median decline in plasma HIV-1 RNA after 7 days was 1.92 and 1.76 log10 copies (P = 0.77) and the median increase of CD4 T cells was 119 x 10(6) and 60 x 10(6) cells/l, respectively (P = 0.29). CONCLUSION: Monotherapy with TMC125 in ART-naive, HIV-1-infected individuals resulted in a similar rate of decline of plasma HIV-1 RNA during 1 week of therapy as therapy with a five-drug regimen.

Compartmentalisation of cytokines and cytokine inhibitors in ventilator-associated pneumonia.

OBJECTIVE: To examine whether cytokine concentrations change in the pulmonary compartment during the development of ventilator-associated pneumonia (VAP). DESIGN: Non-directed bronchial lavage (NBL) was performed every 48 h in critically ill mechanically ventilated patients. Serial measurements of the cytokines tumor necrosis factor (TNF) alpha, interleukin (IL)-1alpha, IL-1beta, IL-6, and IL-10 and the cytokine inhibitors soluble TNFalpha receptor type I (sTNFalphaRI), IL-1 receptor antagonist (IL-1Ra) and soluble IL-1 receptor II (sIL-1RII) were performed on the NBL fluid and matching plasma samples by ELISA. SETTING: An adult medical and surgical university hospital intensive care unit. PATIENTS: Nine patients who developed VAP and nineteen patients who did not develop VAP served as controls. INTERVENTIONS: None. RESULTS: Plasma concentrations of the measured cytokines and cytokine inhibitors did not change significantly in any patients. In control patients, NBL fluid concentrations of sIL-1RII decreased significantly over time (P=0.01). In patients who developed VAP, NBL fluid concentrations of TNFalpha, sTNFalphaRI, IL-1alpha, and IL-1beta increased significantly (P=0.002, P=0.03, P=0.04 and P=0.02, respectively). Furthermore, NBL fluid/plasma concentration ratios for TNFalpha, sTNFalphaRI, IL-1alpha, IL-1Ra and IL-6 increased significantly as VAP developed (P=0.001, P=0.001, P=0.04, P=0.03, and P=0.04, respectively). CONCLUSION: Our results suggest that the production of important cytokines and cytokine inhibitors is compartmentalised within the lung in critically ill mechanically ventilated patients who develop VAP.

A survey of infectious agents as risk factors for primary sclerosing cholangitis: are Chlamydia species involved?

OBJECTIVES: The aetiology of primary sclerosing cholangitis (PSC) is unknown, and the role of micro-organisms has been studied only to a limited extent. We tested the hypothesis that past or persisting infection with common viruses or atypical bacteria might play a role in genetically susceptible hosts. DESIGN: Case-control study. METHODS: Serological screening for antibodies against 22 viruses as well as Chlamydia spp. and Mycoplasma pneumoniae was carried out in 41 well-established PSC patients. All 5110 sera tested in 1997 for these micro-organisms at our laboratory served as a background reference group. Subsequently, Chlamydia anti-lipopolysaccharide (LPS) antibodies were determined by enzyme-linked immunosorbent assay (ELISA) in the PSC group and in three race-matched control groups (inflammatory bowel disease (IBD) group, n = 35; non-IBD patients group, n = 39; healthy blood donor group, n = 40). Subtyping in Chlamydia trachomatis and C. pneumoniae serotypes by specific anti-major outer membrane protein (MOMP) assays was carried out in the four groups. Immunohistochemical staining using specific markers for chlamydiae was carried out on liver biopsies of 14 PSC patients. RESULTS: There was a markedly elevated seroprevalence of Chlamydia-LPS antibodies compared with the 1997 reference group. The odds ratios (ORs) for the presence of immunoglobulin G, immunoglobulin M and immunoglobulin A antibodies for the PSC patients versus the control group were 2.4 (95% confidence interval (CI) 1.1 to 5.4), 1.9 (95% CI 0.9 to 4.0) and 6.7 (95% CI 3.0 to 17.0), respectively. All other micro-organisms tested showed normal antibody profiles that did not differ from the 1997 reference group. The seroprevalence of Chlamydia-anti-LPS antibodies was elevated markedly in the PSC patients compared with the IBD, non-IBD and blood donor groups. The outcomes in the C. trachomatis and C. pneumoniae anti-MOMP assays did not correlate with the anti-LPS-positive PSC sera. The actual presence of Chlamydia bodies in liver tissue could not be demonstrated. CONCLUSION: Our findings suggest an association between PSC and (previous) infection with Chlamydia.

International seroepidemiology of adenovirus serotypes 5, 26, 35, and 48 in pediatric and adult populations.

Recombinant adenovirus serotype 5 (rAd5) vaccine vectors for HIV-1 and other pathogens have been shown to be limited by high titers of Ad5 neutralizing antibodies (NAbs) in the developing world. Alternative serotype rAd vectors have therefore been constructed. Here we report Ad5, Ad26, Ad35, and Ad48 NAb titers in 4381 individuals from North America, South America, sub-Saharan Africa, and Southeast Asia. As expected, Ad5 NAb titers were both frequent and high magnitude in sub-Saharan Africa and Southeast Asia. In contrast, Ad35 NAb titers proved infrequent and low in all regions studied, and Ad48 NAbs were rare in all regions except East Africa. Ad26 NAbs were moderately common in adults in sub-Saharan Africa and Southeast Asia, but Ad26 NAb titers proved markedly lower than Ad5 NAb titers in all regions, and these relatively low Ad26 NAb titers did not detectably suppress the immunogenicity of 4×10(10)vp of a rAd26-Gag/Pol/Env/Nef vaccine in rhesus monkeys. These data inform the clinical development of alternative serotype rAd vaccine vectors in the developing world.

Age dependence of adenovirus-specific neutralizing antibody titers in individuals from sub-Saharan Africa.

We assessed neutralizing antibody titers to adenovirus serotype 5 (Ad5) and six rare adenovirus serotypes, serotypes 11, 35, 50, 26, 48, and 49, in pediatric populations in sub-Saharan Africa. We observed a clear age dependence of Ad5-specific neutralizing antibody titers. These data will help to guide the development of Ad vector-based vaccines for human immunodeficiency virus type 1 and other pathogens.