Consistency between Treatment Effects on Clinical and Brain Atrophy Outcomes in Alzheimer's Disease Trials.

BACKGROUND: Longitudinal changes in volumetric MRI outcome measures have been shown to correlate well with longitudinal changes in clinical instruments and have been widely used as biomarker outcomes in clinical trials for Alzheimer's disease (AD). While instances of discordant findings have been noted in some trials, especially the recent amyloid-removing therapies, the overall relationship between treatment effects on brain atrophy and clinical outcomes, and how it might depend on treatment target or mechanism, clinical instrument or imaging variable is not yet clear. OBJECTIVE: To systematically assess the consistency and therapeutic class-dependence of treatment effects on clinical outcomes and on brain atrophy in published reports of clinical trials conducted in mild cognitive impairment (MCI) and/or AD. DESIGN: Quantitative review of the published literature. The consistency of treatment effects on clinical and brain atrophy outcomes was assessed in terms of statistical agreement with hypothesized equal magnitude effects (e.g., 30% slowing of both) and nominal directional concordance, as a function of therapeutic class. SETTING: Interventional randomized clinical trials. PARTICIPANTS: MCI or AD trial participants. INTERVENTION: Treatments included were those that involved ingestion or injection of a putatively active substance into the body, encompassing both pharmacological and controlled dietary interventions. MEASUREMENTS: Each trial included in the analysis reported at least one of the required clinical outcomes (ADAS-Cog, CDR-SB or MMSE) and at least one of the required imaging outcomes (whole brain, ventricular or hippocampal volume). RESULTS: Data from 35 trials, comprising 185 pairwise comparisons, were included. Overall, the 95% confidence bounds overlapped with the line of identity for 150/185 (81%) of the imaging-clinical variable pairs. The greatest proportion of outliers was found in trials of anti-amyloid antibodies that have been shown to dramatically reduce the level of PET-detectable amyloid plaques, for which only 13/33 (39%) of observations overlapped the identity line. A Deming regression calculated using all data points yielded a slope of 0.54, whereas if data points from the amyloid remover class were excluded, the Deming regression line had a slope of 0.92. Directional discordance of treatment effects was also most pronounced for the amyloid-removing class, and for comparisons involving ventricular volume. CONCLUSION: Our results provide a frame of reference for the interpretation of clinical and brain atrophy results from future clinical trials and highlight the importance of mechanism of action in the interpretation of imaging results.

Lessons learned during implementation of MR-guided High-Intensity Focused Ultrasound treatment of uterine fibroids.

BACKGROUND: Although promising results have been reported for Magnetic Resonance image-guided High-Intensity Focused Ultrasound (MR-HIFU) treatment of uterine fibroids, this treatment is not yet widely implemented in clinical practice. During the implementation of a new technology, lessons are learned and an institutional learning-curve often has to be completed. The primary aim of our prospective cohort study was to characterize our learning-curve based on our clinical outcomes. Secondary aims included identifying our lessons learned during implementation of MR-HIFU on a technical, patient selection, patient counseling, medical specialists and organizational level. RESULTS: Our first seventy patients showed significant symptom reduction and improvement of quality of life at 3, 6 and 12 months after MR-HIFU treatment compared to baseline. After the first 25 cases, a clear plateau phase was reached in terms of failed treatments. The median non-perfused volume percentage of these first 25 treatments was 44.6% (range: 0-99.7), compared to a median of 74.7% (range: 0-120.6) for the subsequent treatments. CONCLUSIONS: Our findings describe the learning-curve during the implementation of MR-HIFU and include straightforward suggestions to shorten learning-curves for future users. Moreover, the lessons we learned on technique, patient selection, patient counseling, medical specialists and organization, together with the provided supplements, may be of benefit to other institutions aiming to implement MR-HIFU treatment of uterine fibroids. Trial registration ISRCTN14634593. Registered January 12, 2021-Retrospectively registered, https://www.isrctn.com/ISRCTN14634593 .

The course of apathy in late-life depression treated with electroconvulsive therapy; a prospective cohort study.

OBJECTIVES: Apathy, a lack of motivation, is frequently seen in older individuals, with and without depression, with substantial impact on quality of life. This prospective cohort study of patients with severe late-life depression treated with electroconvulsive therapy (ECT) aims to study the course of apathy and the predictive value of vascular burden and in particular white matter hyperintensities on apathy course. METHODS: Information on apathy (defined by a score of >13 on the Apathy Scale), depression severity, vascular burden, and other putative confounders was collected in at 2 psychiatric hospitals on patients with late-life depression (aged 55 to 87 years, N = 73). MRI data on white matter hyperintensities were available in 52 patients. Possible risk factors for apathy post-ECT were determined using regression analyses. RESULTS: After treatment with ECT, 52.0% (26/50) of the depression remitters still suffered from clinically relevant apathy symptoms. In the entire cohort, more patients remained apathetic (58.9%) than depressed (31.5%). Presence of apathy post-ECT was not associated with higher age, use of benzodiazepines, or severity of apathy and depression at baseline. Less response in depressive symptomatology after ECT predicted post-treatment apathy. The presence of vascular disease, diabetes mellitus and smoking, and white matter hyperintensities in the brain was not associated with post-treatment apathy. CONCLUSIONS: Apathy may perpetuate in individual patients, despite remission of depressive symptoms. In this cohort of patients with late-life depression, post-ECT apathy is not associated with white matter hyperintensities.

Functional and effective whole brain connectivity using magnetoencephalography to identify monozygotic twin pairs.

Resting-state functional connectivity patterns are highly stable over time within subjects. This suggests that such 'functional fingerprints' may have strong genetic component. We investigated whether the functional (FC) or effective (EC) connectivity patterns of one monozygotic twin could be used to identify the co-twin among a larger sample and determined the overlap in functional fingerprints within monozygotic (MZ) twin pairs using resting state magnetoencephalography (MEG). We included 32 cognitively normal MZ twin pairs from the Netherlands Twin Register who participate in the EMIF-AD preclinAD study (average age 68 years). Combining EC information across multiple frequency bands we obtained an identification rate over 75%. Since MZ twin pairs are genetically identical these results suggest a high genetic contribution to MEG-based EC patterns, leading to large similarities in brain connectivity patterns between two individuals even after 60 years of life or more.

Consequence of restaging after neoadjuvant treatment for locally advanced rectal cancer.

BACKGROUND: Locally advanced rectal cancer is customarily treated with neoadjuvant chemoradiotherapy (CRT) followed by a total mesorectal excision. During the course of CRT, previously non-detectable distant metastases can appear. Therefore, a restaging CT scan of the chest and abdomen was performed prior to surgery. The aim of this study was to determine the frequency of a change in treatment strategy after this restaging CT scan. METHODS: Patients treated with neoadjuvant CRT for locally advanced rectal cancer between January 2003 and July 2013 were included retrospectively. To determine the value of the restaging CT scan, the surgical treatment as planned before CRT was compared with the treatment ultimately received. RESULTS: A total of 153 patients (91 male) were eligible, and median age was 62 (32-82) years. The restaging CT scan revealed the presence of distant metastases in 19 patients (12.4, 95 % confidence interval [CI] 7.0-17.8). In 17 patients (11.1, 95 % CI 6.1-16.1), a change in treatment strategy occurred due to the detection of metastases with a restaging CT scan. CONCLUSION: A restaging CT scan after completion of neoadjuvant CRT may detect newly developed metastases and consequently alter the initial treatment strategy. This study demonstrated the added value of the restaging CT scan prior to surgery.

Dynamics of interferon-gamma release assay and cytokine profiles in blood and respiratory tract specimens from mice with tuberculosis and the effect of therapy.

There are limitations on diagnostic methods to differentiate between active and latent tuberculosis (TB), and the prediction of latent progression to TB disease is yet complex. Traditionally, tuberculosis-specific host immune response was visualized using the tuberculin skin test. Nowadays, IFN-γ release assays (IGRA) provide a more specific and sensitive tool, by which exposure to Mtb could be determined. However, the merit of IGRA aids in diagnosing active TB is yet unclear. We adapted IGRA for use in mice, and quantifying bead-based flow cytometry techniques were used to assess cytokine profiles during the course of untreated infection and to investigate the value of IGRA and cytokines as biomarkers for therapy response. High variability of IGRA results during progression of active TB infection related to various phases of infection was obtained. However, a significant decrease in IGRA results and in levels of IFN-γ, IL-17, IP-10 or MIG was observed and appeared to be associated with successful therapy. This outcome does not support the value of IGRA to accurately diagnose active TB or to monitor infection progression. However, IGRA proved to be a useful biomarker to monitor therapy success. In addition, different cytokines might serve as biomarkers.

Course of murine tuberculosis and response to first-line therapy depends on route of infection and inoculum size.

BACKGROUND: In the search for new anti-tuberculosis drugs, numerous potential drugs are being screened in vitro. In animal models, promising new anti-tuberculosis drugs are assessed in terms of toxic side effects and comparative therapeutic efficacy. Mice are frequently used and experimental infections are established in different ways. OBJECTIVE: To investigate to what extent the route of Mycobacterium tuberculosis inoculation is a determinant in the pathogenesis of tuberculosis (TB) and the therapeutic outcome. Results will contribute to insight into the translational value of TB models used for preclinical studies. DESIGN: TB in mice was established through intratracheal or intravenous mycobacterial inoculation. The efficacy of a 26-week treatment regimen was evaluated, including assessment of relapse of infection 13 weeks post-treatment. RESULTS: It was shown that the course of TB and the therapeutic response, in terms of histopathological characteristics and mycobacterial load, in lungs and extra- pulmonary organs is substantially different and dependent on the route of infection applied and the inoculum size used. CONCLUSION: When evaluating the comparative therapeutic potential of novel anti-tuberculosis drugs or drug treatment schedules investigated in different studies, it should be noted that the route of infection applied and the inoculum size used influence the course of murine TB and the therapeutic response to the standard first- line anti-tuberculosis drug regimen.

A prospective cohort study on the absolute risks of venous thromboembolism and predictive value of screening asymptomatic relatives of patients with hereditary deficiencies of protein S, protein C or antithrombin.

BACKGROUND: Absolute risks of venous thromboembolism (VTE) in protein S-, protein C-, or antithrombin-deficient subjects are mainly based on retrospective data. Screening asymptomatic relatives of these patients is disputed, though studies addressing this issue have yet to be conducted. METHODS: We prospectively followed 382 relatives of 84 probands. Participants were assessed for other thrombophilic defects and occurrence of exogenous risk factors (i.e. surgery/trauma/immobilization, malignancies, use of systemic estrogens, and pregnancy/puerperium). After screening, deficient subjects were advised to use thromboprophylaxis during exogenous risk factors; use of oral contraceptives was discouraged. RESULTS: Overall annual incidence of VTE was 1.53% (95% CI, 1.00-2.34) in deficient vs. 0.29% (0.13-0.64) in non-deficient relatives; adjusted hazard ratio, 7.0 (95% CI, 2.7-18.0). Annual incidence of unprovoked VTE was 0.95% in deficient vs. 0.05% in non-deficient subjects; age-adjusted hazard ratio, 22.3 (P = 0.003). In contrast, annual incidence of provoked VTE was 0.58% vs. 0.24%; age-adjusted hazard ratio, 2.8 (P = 0.08). Fifty-five (37%) deficient and 80 (34%) non-deficient subjects experienced 91 and 143 exogenous risk factors, respectively, during which six vs. five VTEs (6.6% vs 3.5% per risk-period) occurred, despite the higher compliance with recommended thromboprophylaxis use in deficient (51%) vs. non-deficient (22%) subjects. In deficient subjects all provoked VTEs occurred when thromboprophylaxis was not used. CONCLUSIONS: Protein S, protein C or antithrombin deficiencies confer high absolute risk of VTE. Screening and subsequent augmentation of thromboprophylaxis use may result in reduction of provoked VTE, whereas risk of unprovoked VTE could not be affected by screening.

Immunological parameters to define infection progression and therapy response in a well-defined tuberculosis model in mice.

To evaluate novel approaches for tuberculosis (TB) diagnostics and treatment, well-validated animal TB models are needed. Especially the emergence and spread of drug resistant TB requires innovative therapy and accurate parameters for monitoring success or failure of therapy. We developed a TB model in BALB/c mice, in which Mycobacterium tuberculosis (Mtb) infection was induced through the natural respiratory route, mimicking human TB infection. The lung showed a mild inflammatory infiltrate consisting of granulomas in the first phase of infection, followed by progressive increase of pneumonic lesions resulting in extensive lung consolidation in the chronic phase. Dissemination to the extra-pulmonary sites was observed. The model was validated in terms of therapeutic outcome. The 26-week standard therapy administered in human pharmacokinetic-equivalent doses, resulted in complete elimination of Mtb in all infected organs, without relapse of infection in the post-treatment period. However, a 13-week therapy, simulating patient non-adherence resulted in relapse of infection. In our quest to find biomarkers for monitoring success or failure of therapy, the concentrations of various cytokines in serum and lung, determined by cytometric bead array (CBA), were evaluated in relation to the in situ cytokine expression in the lung, assessed by immunohistochemistry. The level of IFN-gamma concentration in serum increased with infection progression, and decreased during effective therapy, and as such appeared to be an appropriate immunological parameter for success or failure of therapy. Relapse of infection, after inappropriate therapy, manifested as an increase in the serum IFN-gamma concentration.

Protein S deficiency: a clinical perspective.

Protein S (PS) is an extensively studied protein with an important function in the down-regulation of thrombin generation. Because of the presence of a pseudogene and two different forms of PS in plasma, a bound and a free form, it is one of the most difficult thrombophilias to study. A deficiency of PS predisposes subjects to (recurrent) venous thromboembolism (VTE) and foetal loss. However, the conundrum of diagnosing PS deficiency has led to conflicting reports of PS as a risk factor for VTE. In this review, we aim to present a clinical perspective of PS deficiency.

A small mammal model of tumour implantation, dissemination and growth factor expression after partial hepatectomy.

BACKGROUND: Surgical resection remains the most effective therapy for metastatic colorectal cancer confined to the liver, although the extrahepatic recurrence rate is high. AIM OF THE STUDY: To develop a mammal model in order to investigate by which mechanisms liver surgery affects distant tumour recurrence. METHODS: In this animal study the effect of partial hepatectomy (phX) on the development of tumour noduli in the lungs was evaluated. CC531 rat colon carcinoma cells were inoculated i.v. 24h before, during or 24h after surgery. Rat serum was obtained at different time-points after phX and added to in vitro CC531 cell cultures. Finally, phX was compared with an ileum resection (ilX). RESULTS: phX leads to increased tumour noduli in the lungs, compared to Sham operation (p=0.002), but only when performed directly before the injection of tumour cells and not when performed 24h before or after the inoculation. Comparable results were obtained for ilX. No growth stimulation of tumour cells after incubation with rat serum, obtained at different time-points after phX, could be detected in vitro. CONCLUSION: Not only phX, but also surgery, in general promotes distant tumour recurrence exerting the effect during the early phase of tumour cell adhesion and not during tumour outgrowth.

Role of ceftazidime dose regimen on the selection of resistant Enterobacter cloacae in the intestinal flora of rats treated for an experimental pulmonary infection.

OBJECTIVES: The effect of ceftazidime dosing increments and frequency of dosing on the selection of ceftazidime-resistant Enterobacter cloacae in the intestine was studied in rats, during treatment of a pulmonary infection caused by Klebsiella pneumoniae. METHODS: Rats with pulmonary infection (n = 10 per group) received therapy with doses of ceftazidime at 3.1 to 400 mg/kg per day at a frequency of every 6,12 or 24 h for 18 days, starting 24 h after bacterial inoculation of the lung. Emergence of resistance in intestinal E. cloacae was monitored by culturing fresh stool specimens at days 0, 8, 15, 22, 29, 36 and 43 on agar plates with (6.4 mg/L) and without ceftazidime. Pharmacodynamic indices and time within the mutant selection window (MSW) were assessed in infected rats for each regimen. Ceftazidime-resistant E. cloacae mutants were characterized by determination of the beta-lactamase activity under cefoxitin-induced and non-induced conditions. RESULTS: A reduction of intestinal ceftazidime-susceptible E. cloacae was observed and showed a significant correlation with the fAUC/MIC at days 8, 15 and 22 and with the fCmax on days 8, 15, 22, 29 and 36. More rats treated with 12-25 and 50-100 mg/kg per day every 6 h were found colonized with ceftazidime-resistant E. cloacae mutants than animals treated every 12 h or every 24 h. The proportion of rats colonized with ceftazidime-resistant E. cloacae mutants at days 15, 36 and 43 correlated with the time during which ceftazidime plasma concentrations were within the boundaries of the MSW. Only at day 15 was a correlation demonstrated between the fCmax and significantly fewer rats colonized with ceftazidime-resistant E. cloacae. Ceftazidime-resistant E. cloacae mutants (MIC >or= 128 mg/L) were characterized as stable derepressed mutants. CONCLUSIONS: Colonization with stable derepressed ceftazidime-resistant E. cloacae mutants particularly occurred when rats were exposed to moderate doses of ceftazidime (12-25 or 50-100 mg/kg per day) administered every 6 h. Emergence of resistance was correlated with time within the MSW.

The role of superoxide anions in the development of distant tumour recurrence.

We hypothesise that reactive oxygen species (ROS) released from activated polymorphonuclear leucocytes during surgery play a crucial role in enhanced tumour recurrence seen after surgery. Therefore, the effect of ROS on adhesion of tumour cells to microvascular endothelium in a reproducible human in vitro model was studied. Preincubation of microvascular endothelial cells with the superoxide anion producing xanthine-xanthine oxidase complex significantly increased adhesion of the human colon carcinoma cells HT29 (167% vs control, P < 0.01), Caco2 (164% vs control, P < 0.01) and of the pancreas carcinoma cells PanC1 (180% vs control, P < 0.01). Addition of the antioxidant enzymes superoxide dismutase or catalase significantly decreased tumour cell adhesion (P < 0.01). Exposure of endothelial cells to superoxide anions increased the apoptotic rate to 7.9 times the normal rate. Additionally, exposure increased expression of the endothelial adhesion molecules E-Selectin, ICAM-1, and VCAM-1 of maximally 170% vs control (P < 0.01). In conclusion, this study shows that superoxide anions promote the adherence of tumour cells to the microvasculature by inducing endothelial apoptosis that subsequently induces the expression of various adhesion molecules for tumour cells. This indicates that by tackling the production of ROS preventing tumour recurrence at distant sites might be feasible.

In vivo synergistic interaction of liposome-coencapsulated gentamicin and ceftazidime.

Antimicrobial agents may interact synergistically. But to ensure synergy in vivo, the drugs should both be present at the site of infection at sufficiently high concentrations for an adequate period of time. Coencapsulation of the drugs in a drug carrier may ensure parallel tissue distributions. Since liposomes localize preferentially at sites of infection, this mode of drug delivery could, in addition, increase drug concentrations at the focus of infection. The therapeutic efficacy of gentamicin and ceftazidime coencapsulated into liposomes was examined by monitoring survival in a rat model of an acute unilateral pneumonia caused by antibiotic-susceptible and antibiotic-resistant Klebsiella pneumoniae strains. It is shown that administration of gentamicin in combination with ceftazidime in the free form either as single dose or as 5-day treatment resulted in an additive effect on rat survival in both models. In contrast, targeted delivery of liposome-coencapsulated gentamicin and ceftazidime resulted in a synergistic interaction of the antibiotics in both models. Consequently, liposome coencapsulation of gentamicin and ceftazidime allowed both a shorter course of treatment at lower cumulative doses compared with administration of the antibiotics in the free form to obtain complete survival of rats. Liposomal coencapsulation of synergistic antibiotics may open new perspectives in the treatment of severe infections.

Improved efficacy of ciprofloxacin administered in polyethylene glycol-coated liposomes for treatment of Klebsiella pneumoniae pneumonia in rats.

Animal and clinical data show that high ratios of the area under the concentration-time curve and the peak concentration in blood to the MIC of fluoroquinolones for a given pathogen are associated with a favorable outcome. The present study investigated whether improvement of the therapeutic potential of ciprofloxacin could be achieved by encapsulation in polyethylene glycol (PEG)-coated long-circulating sustained-release liposomes. In a rat model of unilateral Klebsiella pneumoniae pneumonia (MIC = 0.1 microg/ml), antibiotic was administered at 12- or 24-h intervals at twofold-increasing doses. A treatment period of 3 days was started 24 h after inoculation of the left lung, when the bacterial count had increased 1,000-fold and some rats had positive blood cultures. The infection was fatal within 5 days in untreated rats. Administration of ciprofloxacin in the liposomal form resulted in delayed ciprofloxacin clearance and increased and prolonged ciprofloxacin concentrations in blood and tissues. The ED(50) (dosage that results in 50% survival) of liposomal ciprofloxacin was 3.3 mg/kg of body weight/day given once daily, and that of free ciprofloxacin was 18.9 mg/kg/day once daily or 5.1 mg/kg/day twice daily. The ED(90) of liposomal ciprofloxacin was 15.0 mg/kg/day once daily compared with 36.0 mg/kg/day twice daily for free ciprofloxacin; 90% survival could not be achieved with free ciprofloxacin given once daily. In summary, the therapeutic efficacy of liposomal ciprofloxacin was superior to that of ciprofloxacin in the free form. PEG-coated liposomal ciprofloxacin was well tolerated in relatively high doses, permitting once daily administration with relatively low ciprofloxacin clearance and without compromising therapeutic efficacy.

Therapeutic efficacy of liposome-encapsulated gentamicin in rat Klebsiella pneumoniae pneumonia in relation to impaired host defense and low bacterial susceptibility to gentamicin.

Long-circulating liposomes (LCL) may be used as targeted antimicrobial drug carriers as they localize at sites of infection. As a result, LCL-encapsulated gentamicin (LE-GEN) has demonstrated superior antibacterial activity over the free drug in a single-dose study of immunocompetent rats with Klebsiella pneumoniae pneumonia. In the present study, the therapeutic efficacy of LE-GEN was evaluated by monitoring rat survival and bacterial counts in blood and lung tissue in clinically relevant models, addressing the issue of impaired host defense and low bacterial antibiotic susceptibility. The results show that in immunocompetent rats infected with the high-GEN-susceptibility K. pneumoniae strain, a single dose of LE-GEN is clearly superior to an equivalent dose of free GEN. Yet complete survival can also be obtained with multiple doses of free GEN. In leukopenic rats infected with the high-GEN-susceptible K. pneumoniae strain, free GEN at the maximum tolerated dose (MTD) was needed to obtain survival. However, with the addition of a single dose of LE-GEN to free-GEN treatment, complete survival can be obtained using a sevenfold-lower cumulative amount of GEN than with free-GEN treatment alone. In leukopenic rats infected with low-GEN-susceptible K. pneumoniae cells, free GEN at the MTD did not result in survival. The use of LE-GEN is needed for therapeutic success. Increasing LE-GEN bilayer fluidity resulted in an increased GEN release from the liposomes and hence improved rat survival, thus showing the importance of the liposome lipid composition for therapeutic efficacy. These results warrant further clinical studies of liposomal formulations of aminoglycosides in immunocompromised patients with severe infections.

Metastasectomy, a feasible treatment in selected cases with gynecologic malignancy.

We present the course of six gynecological patients who underwent surgical intervention because of a solitary metastasis. After a considerable follow-up period five patients are alive without evidence of disease and with a good quality of life. Metastasectomy should play a role in the management of gynecologic malignancies.