Identification of altered dipeptidyl-peptidase activities as potential biomarkers for unipolar depression

Background

Changes in circulatory aminopeptidases [dipeptidyl-peptidase-IV (DPP-IV), Prolyl-oligopeptidase (POP) and Leucine aminopeptidase (LAP)] activities have been found to be associated with psychiatric illnesses and inflammatory diseases.

Methods

The discriminatory indices of aminopeptidases activities were assessed by enzymatic assays in plasma samples from 240 unipolar depression (UD) patients and 264 matched controls. In addition the relationship between soluble and cellular DPP-IV activity was determined in plasma and blood cells from healthy subjects.

Results

Greater than 95% of the plasma DPP-IV activity could be blocked by inhibitors, demonstrating the specificity of the assay. Also, DPP-IV protein and activity levels were strongly correlated. In contrast, only 50% of the membrane-bound activity in blood cells was inhibited, which suggested that other similar peptidases may be present in these cells. UD patients had decreased plasma levels of DPP-IV and POP activities compared to healthy controls with a concomitant increase in LAP activity. Finally, testing of the LAP/DPP-IV ratio resulted in good discrimination of UD patients from controls with an area under the curve—receiver operating characteristic of 0.70.

Limitations

Further biological validation studies using different cohorts are warranted.

Conclusions

The finding that plasma DPP-IV activity was decreased and LAP activity was increased in UD patients suggests the potential value for testing the levels of these enzymes for improved classification of patients. In addition, the changes in these enzymes, suggests that the proteolytic maturation of their proneuropeptide and prohormone subtrates may also be affected in UD, resulting in altered production of the associated bioactive peptides.     

Multisite rTMS for the Treatment of Chronic Tinnitus: Stimulation of the Cortical Tinnitus Network—A Pilot Study

Low-frequency repetitive transcranial magnetic stimulation (rTMS) of the auditory cortex has been shown to significantly reduce tinnitus severity in some patients. There is growing evidence that a neural network of both auditory and non-auditory cortical areas is involved in the pathophysiology of chronic subjective tinnitus. Targeting several core regions of this network by rTMS might constitute a promising strategy to enhance treatment effects. This study intends to test the effects of a multisite rTMS protocol on tinnitus severity. 45 patients with chronic tinnitus were treated with multisite stimulation (left dorsolateral prefrontal, 2,000 stimuli, 20 Hz; left temporoparietal, 1,000 stimuli, 1 Hz; right temporoparietal, 1,000 stimuli, 1 Hz). Results were compared with a historical control group consisting of 29 patients who received left temporal stimulation (2,000 stimuli, 1 Hz). Both groups were treated on ten consecutive working days. Tinnitus severity was assessed at three time points: at baseline, after the last treatment session (day 12) and after a follow-up period of 90 days. A change of tinnitus severity over time was tested using repeated measures ANOVA with the between-subjects factor treatment group. Both groups improved similarly from baseline to day 12. However, there was a difference on day 90: the multisite stimulation group showed an overall improvement whereas patients receiving temporal stimulation returned to their baseline level of tinnitus severity. These pilot data suggest that multisite rTMS is superior to temporal rTMS and represents a promising strategy for enhancing treatment effects of rTMS in tinnitus. Future studies should explore this new protocol with respect to clinical and neurobiological effects in more detail.     

High frequency of disease progression in pediatric spinal cord low-grade glioma (LGG): management strategies and results from the German LGG study group

BackgroundKnowledge on management of pediatric spinal cord low-grade glioma (LGG) is scarce.MethodsWe analyzed clinical datasets of 128 pediatric patients with spinal LGG followed within the prospective multicenter trials HIT-LGG 1996 (n = 36), SIOP-LGG 2004 (n = 56), and the subsequent LGG-Interim registry (n = 36).ResultsSpinal LGG, predominantly pilocytic astrocytomas (76%), harbored KIAA1549-BRAF fusion in 14/35 patients (40%) and FGFR1-TACC1 fusion in 3/26 patients (12%), as well as BRAFV600E mutation in 2/66 patients (3%). 10-year overall survival (OS) and event-free survival (EFS) was 93% ± 2% and 38% ± 5%, respectively. Disseminated disease (n = 16) was associated with inferior OS and EFS, while age ≥11 years and total resection were favorable factors for EFS. We observed 117 patients following total (n = 24) or subtotal/partial resection (n = 74), biopsy (n = 16), or radiologic diagnosis only (n = 3). Eleven patients were treated first with chemotherapy (n = 9) or irradiation (n = 2). Up to 20.8 years after diagnosis/initial intervention, 73/128 patients experienced one (n = 43) or up to six (n = 30) radiological/clinical disease progressions. Tumor resections were repeated in 36 patients (range, 2-6) and 47 patients required nonsurgical treatment (chemotherapy, n = 20; radiotherapy, n = 10; multiple treatment lines, n = 17). Long-term disease control for a median of 6.5 (range, 0.02-20) years was achieved in 73/77 patients following one (n = 57) or repeated (n = 16) resections, and in 35/47 patients after nonsurgical treatment.ConclusionsThe majority of patients experienced disease progression, even after years. Multiple interventions were required for more than a third, yet multimodal treatment enabled long-term disease control. Molecular testing may reveal therapeutic targets.     

Default network is not hypoactive in dementia with fluctuating cognition: an Alzheimer disease/dementia with Lewy bodies comparison

Default mode network resting state activity in posterior cingulate cortex is abnormally reduced in Alzheimer disease (AD) patients. Fluctuating cognition and electroencephalogram abnormalities are established core and supportive elements respectively for the diagnosis of dementia with Lewy bodies (DLB). Our aim was to assess whether patients with DLB with both of these features have different default mode network patterns during resting state functional magnetic resonance imaging compared with AD. Eighteen patients with DLB, 18 AD patients without fluctuating cognition, and 15 control subjects were selected after appropriate matching and followed for 2–5 years to confirm diagnosis. Independent component analysis with functional connectivity (FC) and Granger causality approaches were applied to isolate and characterize resting state networks. FC was reduced in AD and DLB patients compared with control subjects. Posterior cingulate cortex activity was lower in AD than in control subjects and DLB patients (p < 0.05). Right hemisphere FC was reduced in DLB patients in comparison with control subjects but not in patients with AD, and was correlated with severity of fluctuations (ρ = −0.69; p < 0.01). Causal flow analysis showed differences between patients with DLB and AD and control subjects.     

Psychotropic medications,including short acting benzodiazepines,strongly increase the frequency of falls in elderly

ObjectivesFalls in the elderly are common and often serious. The aim of this study was to examine the association between the use of different classes of psychotropic medications, especially short acting benzodiazepines, and the frequency of falling in elderly.Study design This retrospective cohort study was performed with patients who visited the day clinic of the department of geriatric medicine of the University Medical Center Utrecht in the Netherlands between 1 January 2011 and 1 April 2012.Measurements Frequencies of falling in the past year and medication use were recorded. Logistic regression analysis was performed to assess the relationship between the frequency of falling in the past year and the use of psychotropic medications.ResultsDuring this period 404 patients were included and 238 (58.9%) of them had experienced one or more falls in the past year. After multivariate adjustment, frequent falls remained significantly associated with exposure to psychotropic medications (odds ratio [OR] 1.96; 95% confidence interval [CI] 1.17–3.28), antipsychotics (OR 3.62; 95% CI 1.27–10.33), hypnotics and anxiolytics (OR 1.81; 95% CI 1.05–3.11), short-acting benzodiazepines or Z-drugs (OR 1.94; 95% CI 1.10–3.42) and antidepressants (OR 2.35; 95% CI 1.33–4.16).ConclusionsThis study confirms that taking psychotropic medication, including short-acting benzodiazepines, strongly increases the frequency of falls in elderly. This relation should be explicitly recognized by doctors prescribing for older people, and by older people themselves. If possible such medication should be avoided for elderly patients especially with other risk factors for falling.     

Trimethoprim-sulfamethoxazole as de-escalation in ventilator-associated pneumonia: a cohort study subanalysis

European Journal of Clinical Microbiology & Infectious Diseases - This is a subanalysis of a previous study which compared the effectiveness of trimetoprim-sulfametoxazole (TMP-SMX) with all...     

Multidisciplinary consensus on sputum induction biosafety during the COVID-19 pandemic

Sputum induction (SI) is the gold standard approach to the non-invasive study of airway inflammation. The differential count of inflammatory cells for SI allows patients with asthma to be classified according to inflammatory phenotypes and predicted therapeutic responses. Since SI involves the generation of aerosols, there is a need to establish a protocol to ensure biosafety in clinical practice during the current COVID-19 pandemic. The multidisciplinary consensus on SI described in this article was developed by 22 experts in SI from different Spanish hospitals who drew on available scientific evidence in achieving consensuated opinions, compiled by means of an electronic survey. We hope that these unified criteria and recommendations will guide health professionals in implementing SI sampling and processing procedures as safely as possible during the COVID-19 pandemic.     

Processes of knowing in the translation of a health communication intervention for dialysis patients awaiting kidney transplantation

ObjectiveTo strengthen patients’ health literacy and their role as active knowledge actors, we developed a health communication intervention including a film-viewing and counselling session for patients awaiting kidney transplantation. We aimed to explore processes of knowing in the translation of the intervention.MethodsWe applied an ethnographic research approach, observing nine intervention sessions with patients and dialysis nurses. Afterwards, the patients and the nurses were interviewed in-depth. Data were analysed using Engebretsen’s modified version of Lonergans’ four-step model of knowing.ResultsThe following knowing processes were identified: i) Knowing as meaning-making; ii) Knowing as acquiring confidence; and iii) Accessing professionals’ and peer experts’ knowledge. Divergent considerations were taken by the different knowledge actors, which had a direct influence on the knowing processes and knowledge translation.ConclusionsThe findings support active interactions between patients and healthcare providers in processes of knowing. These include self-conscious approaches and critical questioning in both parties.Practice implicationsFor transplant professionals, this study demonstrates knowing processes in a real-life context. It also spotlights professional skills and attitudes regarding the importance of self-conscious questioning and a critical interrogating position (for both patients and providers).