55 research outputs found
Serotonin and corticosterone rhythms in mice exposed to cigarette smoke and in patients with COPD:implication for COPD-associated neuropathogenesis
The circadian timing system controls daily rhythms of physiology and behavior, and disruption of clock function can trigger stressful life events. Daily exposure to cigarette smoke (CS) can lead to alteration in diverse biological and physiological processes. Smoking is associated with mood disorders, including depression and anxiety. Patients with chronic obstructive pulmonary disease (COPD) have abnormal circadian rhythms, reflected by daily changes in respiratory symptoms and lung function. Corticosterone (CORT) is an adrenal steroid that plays a considerable role in stress and anti-inflammatory responses. Serotonin (5-hydroxytryptamine; 5HT) is a neurohormone, which plays a role in sleep/wake regulation and affective disorders. Secretion of stress hormones (CORT and 5HT) is under the control of the circadian clock in the suprachiasmatic nucleus. Since smoking is a contributing factor in the development of COPD, we hypothesize that CS can affect circadian rhythms of CORT and 5HT secretion leading to sleep and mood disorders in smokers and patients with COPD. We measured the daily rhythms of plasma CORT and 5HT in mice following acute (3 d), sub-chronic (10 d) or chronic (6 mo) CS exposure and in plasma from non-smokers, smokers and patients with COPD. Acute and chronic CS exposure affected both the timing (peak phase) and amplitude of the daily rhythm of plasma CORT and 5HT in mice. Acute CS appeared to have subtle time-dependent effects on CORT levels but more pronounced effects on 5HT. As compared with CORT, plasma 5HT was slightly elevated in smokers but was reduced in patients with COPD. Thus, the effects of CS on plasma 5HT were consistent between mice and patients with COPD. Together, these data reveal a significant impact of CS exposure on rhythms of stress hormone secretion and subsequent detrimental effects on cognitive function, depression-like behavior, mood/anxiety and sleep quality in smokers and patients with COPD
Comparison of the diagnostic accuracy of commercial NS1-based diagnostic tests for early dengue infection
<p>Abstract</p> <p>Background</p> <p>We compared the diagnostic accuracy and reproducibility of commercially available NS1-based dengue tests and explored factors influencing their sensitivities.</p> <p>Methods</p> <p>Paired analysis of 310 samples previously characterized as positive (n = 218) and negative (n = 92) for viral isolation and/or RT-PCR and/or IgM seroconversion. Masked samples were tested by two observers with Platelia™ Dengue NS1 Ag, second generation Pan-E™ Dengue Early ELISA, SD Dengue NS1 Ag ELISA, Dengue NS1 Ag STRIP™, and SD BIOLINE™ Dengue Duo (NS1/IgM/IgG).</p> <p>Results</p> <p>SD BIOLINE™ NS1/IgM/IgG had the highest sensitivity (80.7% 95%CI 75-85.7) with likelihood ratios of 7.4 (95%CI 4.1-13.8) and 0.21 (95%CI 0.16-0.28). The ELISA-format tests showed comparable sensitivities; all below 75%. STRIP™ and SD NS1 had even lower sensitivities (<65%). The sensitivities significantly decreased in samples taken after 3 days of fever onset, in secondary infections, viral serotypes 2 and 4, and severe dengue. Adding IgM or IgG to SD NS1 increased its sensitivity in all these situations.</p> <p>Conclusions</p> <p>The simultaneous detection of NS1/IgM/IgG would be potentially useful for dengue diagnosis in both endemic and non endemic areas. A negative result does not rule out dengue. Further studies are required to assess the performance and impact of early laboratory diagnosis of dengue in the routine clinical setting.</p
Sentinel network for monitoring in vitro susceptibility of Plasmodium falciparum to antimalarial drugs in Colombia: a proof of concept
Drug resistance is one of the principal obstacles blocking worldwide malaria control. In Colombia, malaria remains a major public health concern and drug-resistant parasites have been reported. In vitro drug susceptibility assays are a useful tool for monitoring the emergence and spread of drug-resistant Plasmodium falciparum. The present study was conducted as a proof of concept for an antimalarial drug resistance surveillance network based on in vitro susceptibility testing in Colombia. Sentinel laboratories were set up in three malaria endemic areas. The enzyme linked immunosorbent assay-histidine rich protein 2 and schizont maturation methods were used to assess the susceptibility of fresh P. falciparum isolates to six antimalarial drugs. This study demonstrates that an antimalarial drug resistance surveillance network based on in vitro methods is feasible in the field with the participation of a research institute, local health institutions and universities. It could also serve as a model for a regional surveillance network. Preliminary susceptibility results showed widespread chloroquine resistance, which was consistent with previous reports for the Pacific region. However, high susceptibility to dihydroartemisinin and lumefantrine compounds, currently used for treatment in the country, was also reported. The implementation process identified critical points and opportunities for the improvement of network sustainability strategies.PAHO [057-1-3144141]; COLCIENCIAS [ID 2229-405-20319]info:eu-repo/semantics/publishedVersio
ZikaPLAN: addressing the knowledge gaps and working towards a research preparedness network in the Americas.
Zika Preparedness Latin American Network (ZikaPLAN) is a research consortium funded by the European Commission to address the research gaps in combating Zika and to establish a sustainable network with research capacity building in the Americas. Here we present a report on ZikaPLAN`s mid-term achievements since its initiation in October 2016 to June 2019, illustrating the research objectives of the 15 work packages ranging from virology, diagnostics, entomology and vector control, modelling to clinical cohort studies in pregnant women and neonates, as well as studies on the neurological complications of Zika infections in adolescents and adults. For example, the Neuroviruses Emerging in the Americas Study (NEAS) has set up more than 10 clinical sites in Colombia. Through the Butantan Phase 3 dengue vaccine trial, we have access to samples of 17,000 subjects in 14 different geographic locations in Brazil. To address the lack of access to clinical samples for diagnostic evaluation, ZikaPLAN set up a network of quality sites with access to well-characterized clinical specimens and capacity for independent evaluations. The International Committee for Congenital Anomaly Surveillance Tools was formed with global representation from regional networks conducting birth defects surveillance. We have collated a comprehensive inventory of resources and tools for birth defects surveillance, and developed an App for low resource regions facilitating the coding and description of all major externally visible congenital anomalies including congenital Zika syndrome. Research Capacity Network (REDe) is a shared and open resource centre where researchers and health workers can access tools, resources and support, enabling better and more research in the region. Addressing the gap in research capacity in LMICs is pivotal in ensuring broad-based systems to be prepared for the next outbreak. Our shared and open research space through REDe will be used to maximize the transfer of research into practice by summarizing the research output and by hosting the tools, resources, guidance and recommendations generated by these studies. Leveraging on the research from this consortium, we are working towards a research preparedness network
Haematological consequences of acute uncomplicated falciparum malaria: a WorldWide Antimalarial Resistance Network pooled analysis of individual patient data
Background: Plasmodium falciparum malaria is associated with anaemia-related morbidity, attributable to host, parasite and drug factors. We quantified the haematological response following treatment of uncomplicated P. falciparum malaria to identify the factors associated with malarial anaemia.
Methods: Individual patient data from eligible antimalarial efficacy studies of uncomplicated P. falciparum malaria, available through the WorldWide Antimalarial Resistance Network data repository prior to August 2015, were pooled using standardised methodology. The haematological response over time was quantified using a multivariable linear mixed effects model with nonlinear terms for time, and the model was then used to estimate the mean haemoglobin at day of nadir and day 7. Multivariable logistic regression quantified risk factors for moderately severe anaemia (haemoglobin < 7 g/dL) at day 0, day 3 and day 7 as well as a fractional fall ≥ 25% at day 3 and day 7.
Results: A total of 70,226 patients, recruited into 200 studies between 1991 and 2013, were included in the analysis: 50,859 (72.4%) enrolled in Africa, 18,451 (26.3%) in Asia and 916 (1.3%) in South America. The median haemoglobin concentration at presentation was 9.9 g/dL (range 5.0–19.7 g/dL) in Africa, 11.6 g/dL (range 5.0–20.0 g/dL) in Asia and 12.3 g/dL (range 6.9–17.9 g/dL) in South America. Moderately severe anaemia (Hb < 7g/dl) was present in 8.4% (4284/50,859) of patients from Africa, 3.3% (606/18,451) from Asia and 0.1% (1/916) from South America. The nadir haemoglobin occurred on day 2 post treatment with a mean fall from baseline of 0.57 g/dL in Africa and 1.13 g/dL in Asia. Independent risk factors for moderately severe anaemia on day 7, in both Africa and Asia, included moderately severe anaemia at baseline (adjusted odds ratio (AOR) = 16.10 and AOR = 23.00, respectively), young age (age < 1 compared to ≥ 12 years AOR = 12.81 and AOR = 6.79, respectively), high parasitaemia (AOR = 1.78 and AOR = 1.58, respectively) and delayed parasite clearance (AOR = 2.44 and AOR = 2.59, respectively). In Asia, patients treated with an artemisinin-based regimen were at significantly greater risk of moderately severe anaemia on day 7 compared to those treated with a non-artemisinin-based regimen (AOR = 2.06 [95%CI 1.39–3.05], p < 0.001).
Conclusions: In patients with uncomplicated P. falciparum malaria, the nadir haemoglobin occurs 2 days after starting treatment. Although artemisinin-based treatments increase the rate of parasite clearance, in Asia they are associated with a greater risk of anaemia during recovery
Optical Design of a Vertically Integrated Array-type Mirau-based OCT system
SPIE Photonics Europe 2014. Bruxelles (Belgique), du 14/04/2014 au 17/04/2014Skin cancer is the most diagnosed type of cancer. While an early treatment usually offers good therapy prospects, effective diagnosis techniques are required. Today traditional biopsy is still the reference diagnostic technique, which has the drawback of a long diagnosis time and invasiveness. In recent years, new optical system based on optical coherence tomography were developed for early diagnostics of skin cancer. But as these systems are still bulky and expensive, they're still available at specialized hospitals only. Therefore we present the optical design of a Vertically Integrated Array-type Mirau-based OCT System (VIAMOS), which will allow non-invasive 3D optical biopsies of skin for early diagnostics of skin cancer. The VIAMOS system constitutes a miniature, low cost, full-field optical coherence tomography system combining swept-source OCT, phase-shifting interferometry and MOEMS technologies. It will provide 3D tomograms of human skin from a measurement volume of 8 x 8 x 0.5 mm³ with an axial and transverse resolution of about 6 µm. The swept-source will be realized as a miniaturized, MEMS-based wavelength-tuning Fabry-Perot Interferometer and a near-infrared superluminescent diode resulting in a linewidth of approximately 1 nm and a scanning range of 50 nm. The wafer stacked measurement device consists of 4 x 4 Mirau-Interferometer channels with movable reference mirrors to realize heterodyne detection and will be fabricated by means of MOEMS technologies. The signal detection will be realized using a fast new developed smart camera chip, which features 4 x 4 multiple regions of interest and on-chip signal processing. In this contribution, we present the optical design of the sensor and provide results of an extensive stray light analysis of the system
Brief report: How many dimensions in the prosocial behavior scale? Psychometric investigation in French-speaking adolescents
Collision tumor in form of primary adenocarcinoma and neuroendocrine carcinoma of the duodenum
<em>Collision tumor</em> is a rare phenomenon characterized by coexistence of completely distinct and independent tumors at the same body location. Collision tumors have been reported in different sites. However, they are extremely uncommon in the duodenum. We report the case of a 52-year old man with a collision tumor in the third portion of the duodenum with two distinct tumors of primary adenocarcinoma and neuroendocrine carcinoma, and both tumors coexisting within a single metastatic lymph node. Immunohistochemistry studies were performed to conclude that this was a case of collision cancer. To the best of our knowledge, this is the first collision tumor case reported to date at this location, and the first report of lymph node with a collision metastasis from a collision tumor. Such tumor is very rare and may thus provide diagnostic challenges. This report also provides a review of other cases on duodenal collision tumors
Progression of aortic calcification is associated with disorders of mineral metabolism and mortality in chronic dialysis patients
Previous studies have shown that simple imaging methods may be useful for detection of vascular calcifications in dialysis patients. Based on annual, plain chest X-rays during follow-up on dialysis, we studied the associations of mineral metabolism with the presence and progression of aortic calcification. In addition, we assessed the impact of aortic calcification on mortality. Three hundred and eighty-four patients who started haemodialysis or peritoneal dialysis between 1997 and 2007 were included (age 61 ± 15 years, 64% male, 61% haemodialysis). Annual chest X-rays were screened for calcification in the aortic arch, and patients were categorized as having no, moderate or severe calcification. Progression was defined as an increase in calcification category during follow-up on dialysis. At baseline, 96 (25%) patients had severe, 205 (53%) patients had moderate and 83 (22%) patients had no aortic calcification. For 237 of the 288 patients with no or moderate calcifications at baseline, X-rays were available for follow-up. During follow-up (mean 2.3 years), aortic calcification progressed in 71 patients (30%). We found that baseline plasma calcium > 9.5 mg/dL and iPTH > 300 pg/mL were associated with progression [odds ratios of 3.1, 95% confidence interval (1.2-8.2) and 4.4 (1.4-14.1), respectively]. Progression of aortic calcification was significantly associated with increased risk of all-cause mortality (hazard ratio: 1.9; 95% CI: 1.2-3.1) and cardiovascular mortality (hazard ratio: 2.7; 95% CI: 1.3-5.6). Aortic calcification progressed in almost a third of the patients during dialysis. Hypercalcaemia and hyperparathyroidism were associated with an increased risk of progression. Progression of aortic calcification was significantly related to an increased mortality ris
- …