Standard microplate based enzyme-linked immunosorbent assays (ELISA) are widely utilized for various nanomedicine, molecular sensing, and disease screening applications, and this multiwell plate ...batched analysis dramatically reduces diagnosis costs per patient compared to nonbatched or nonstandard tests. However, their use in resource-limited and field-settings is inhibited by the necessity for relatively large and expensive readout instruments. To mitigate this problem, we created a hand-held and cost-effective cellphone-based colorimetric microplate reader, which uses a 3D-printed opto-mechanical attachment to hold and illuminate a 96-well plate using a light-emitting-diode (LED) array. This LED light is transmitted through each well, and is then collected via 96 individual optical fibers. Captured images of this fiber-bundle are transmitted to our servers through a custom-designed app for processing using a machine learning algorithm, yielding diagnostic results, which are delivered to the user within ∼1 min per 96-well plate, and are visualized using the same app. We successfully tested this mobile platform in a clinical microbiology laboratory using FDA-approved mumps IgG, measles IgG, and herpes simplex virus IgG (HSV-1 and HSV-2) ELISA tests using a total of 567 and 571 patient samples for training and blind testing, respectively, and achieved an accuracy of 99.6%, 98.6%, 99.4%, and 99.4% for mumps, measles, HSV-1, and HSV-2 tests, respectively. This cost-effective and hand-held platform could assist health-care professionals to perform high-throughput disease screening or tracking of vaccination campaigns at the point-of-care, even in resource-poor and field-settings. Also, its intrinsic wireless connectivity can serve epidemiological studies, generating spatiotemporal maps of disease prevalence and immunity.
Background The question of whether gender-related disparities still exist in the treatment and outcomes of patients presenting with acute coronary syndromes (ACS) remains controversial. Using data ...from 4 registries spanning a decade, we sought to determine whether sex-related differences have persisted over time and to examine the treating physician's rationale for adopting a conservative management strategy in women compared with men. Methods From 1999 to 2008, 14,196 Canadian patients with non–ST-segment elevation ACS were recruited into the Acute Coronary Syndrome I (ACSI), ACSII, Global Registry of Acute Coronary Events (GRACE/GRACE2 ), and Canadian Registry of Acute Coronary Events (CANRACE) prospective multicenter registries. Results Women in the study population were found to be significantly older than men and were more likely to have a history of heart failure, diabetes, or hypertension. Fewer women were treated with thienopyridines, heparin, and glycoprotein IIb/IIIa inhibitors compared with men in GRACE and CANRACE. Female gender was independently associated with a lower in-hospital use of coronary angiography (adjusted odds ratio 0.76, 95% CI 0.69-0.84, P < .001) and higher in-hospital mortality (adjusted odds ratio 1.26, 95% CI 1.02-1.56, P = .036), irrespective of age ( P for interaction =.76). Underestimation of patient risk was the most common reason for not pursuing an invasive strategy in both men and women. Conclusions Despite temporal increases in the use of invasive cardiac procedures, women with ACS are still more likely to be treated conservatively, which may be due to underestimation of patient risk. Furthermore, they have worse in-hospital outcomes. Greater awareness of this paradox may assist in bridging the gap between current guidelines and management practices.
Astrocytes have important roles in the central nervous system (CNS) during health and disease. Through genome-wide analyses we detected a transcriptional response to type I interferons (IFN-Is) in ...astrocytes during experimental CNS autoimmunity and also in CNS lesions from patients with multiple sclerosis (MS). IFN-I signaling in astrocytes reduces inflammation and experimental autoimmune encephalomyelitis (EAE) disease scores via the ligand-activated transcription factor aryl hydrocarbon receptor (AHR) and the suppressor of cytokine signaling 2 (SOCS2). The anti-inflammatory effects of nasally administered interferon (IFN)-β are partly mediated by AHR. Dietary tryptophan is metabolized by the gut microbiota into AHR agonists that have an effect on astrocytes to limit CNS inflammation. EAE scores were increased following ampicillin treatment during the recovery phase, and CNS inflammation was reduced in antibiotic-treated mice by supplementation with the tryptophan metabolites indole, indoxyl-3-sulfate, indole-3-propionic acid and indole-3-aldehyde, or the bacterial enzyme tryptophanase. In individuals with MS, the circulating levels of AHR agonists were decreased. These findings suggest that IFN-Is produced in the CNS function in combination with metabolites derived from dietary tryptophan by the gut flora to activate AHR signaling in astrocytes and suppress CNS inflammation.
The gut microbiome plays an important role in immune function and has been implicated in several autoimmune disorders. Here we use 16S rRNA sequencing to investigate the gut microbiome in subjects ...with multiple sclerosis (MS, n=60) and healthy controls (n=43). Microbiome alterations in MS include increases in Methanobrevibacter and Akkermansia and decreases in Butyricimonas, and correlate with variations in the expression of genes involved in dendritic cell maturation, interferon signalling and NF-kB signalling pathways in circulating T cells and monocytes. Patients on disease-modifying treatment show increased abundances of Prevotella and Sutterella, and decreased Sarcina, compared with untreated patients. MS patients of a second cohort show elevated breath methane compared with controls, consistent with our observation of increased gut Methanobrevibacter in MS in the first cohort. Further study is required to assess whether the observed alterations in the gut microbiome play a role in, or are a consequence of, MS pathogenesis.
Background Left atrial appendage occlusion (LAAO) has emerged as an alternative to oral anticoagulation therapy for stroke prevention in atrial fibrillation, but data comparing LAAO with direct oral ...anticoagulant (DOAC) are sparse. Methods and Results This cohort study compared LAAO (with or without prior anticoagulation) with a switch of one DOAC to another DOAC by 1:2 propensity score matching. The primary outcome was a composite of all-cause mortality, ischemic stroke, and major bleeding. A total of 2350 patients (874 in the LAAO group and 1476 in the DOAC switch group) were included. After a mean follow-up of 1052±694 days, the primary outcome developed in 215 (24.6%) patients in the LAAO group and in 335 (22.7%) patients in the DOAC switch group (hazard ratio HR, 0.94 95% CI, 0.80-1.12;
=0.516). The LAAO group had a lower all-cause mortality (HR, 0.49 95% CI, 0.39-0.60;
<0.001) and cardiovascular mortality (HR, 0.49 95% CI, 0.32-0.73;
<0.001) but similar risk of ischemic stroke (HR, 0.83 95% CI, 0.63-1.10;
=0.194). The major bleeding risk was similar overall (HR, 1.18 95% CI, 0.94-1.48,
=0.150) but was lower in the LAAO group after 6 months (HR, 0.71 95% CI, 0.51-0.97;
=0.032). Conclusions LAAO conferred a similar risk of composite outcome of all-cause mortality, ischemic stroke, and major bleeding, as compared with DOAC switch. The risks of all-cause mortality and cardiovascular mortality were lower with LAAO.
Aims Previous studies have reported differences in the use of cardiovascular medications for acute coronary syndromes (ACSs) according to the sex of the patient. We analysed which clinical factors ...are associated with underutilization of evidence-based therapies in women. Methods and results From the Canadian Registry of ACS I and II, 6558 patients (4471 men and 2087 women) with a final diagnosis of ACS were selected for the current analysis. Covariates were chosen using the approach described by Blackstone. The final selected model included 23 patient clinical variables. Women were less likely than men to receive beta-blockers (75.76 vs. 79.24%; P < 0.01), lipid-modifying agents (56.37 vs. 65.44%; P < 0.0001), and angiotensin-converting enzyme (ACE)-inhibitors (55.52 vs. 59.99%; P < 0.01). Female sex and clinical decision not to investigate with cardiac catheterization were the strongest independent predictors for not receiving lipid-modifying agents and ACE-inhibitors. Age, Killip class 2, and Killip class 3/4 were significant independent predictors of underutilization of beta-blocker use. Women were older (69 ± 12 vs. 64 ± 12; P < 0.01) with a higher prevalence of Killip class ≥ 2 (19.95 vs. 15.54%; P < 0.068), and they were less likely to be referred for cardiac catheterization (41.9 vs. 49.6 %; P < 0.001). Conclusions The current findings demonstrate that underutilization of evidence-based therapies in women with ACS compared with men is associated with multiple factors related to the patient (age), the consequences of the disease (congestive heart failure), and the physician's assessment of patient risk (decision to catheterize). Female gender remains associated with underutilization of lipid-modifying agents and ACE-inhibitors despite adjustment for these confounders.
Rapid and sensitive detection of waterborne pathogens in drinkable and recreational water sources is crucial for treating and preventing the spread of water related diseases, especially in ...resource-limited settings. Here we present a field-portable and cost-effective platform for detection and quantification of Giardia lamblia cysts, one of the most common waterborne parasites, which has a thick cell wall that makes it resistant to most water disinfection techniques including chlorination. The platform consists of a smartphone coupled with an opto-mechanical attachment weighing ~205 g, which utilizes a hand-held fluorescence microscope design aligned with the camera unit of the smartphone to image custom-designed disposable water sample cassettes. Each sample cassette is composed of absorbent pads and mechanical filter membranes; a membrane with 8 μm pore size is used as a porous spacing layer to prevent the backflow of particles to the upper membrane, while the top membrane with 5 μm pore size is used to capture the individual Giardia cysts that are fluorescently labeled. A fluorescence image of the filter surface (field-of-view: ~0.8 cm(2)) is captured and wirelessly transmitted via the mobile-phone to our servers for rapid processing using a machine learning algorithm that is trained on statistical features of Giardia cysts to automatically detect and count the cysts captured on the membrane. The results are then transmitted back to the mobile-phone in less than 2 minutes and are displayed through a smart application running on the phone. This mobile platform, along with our custom-developed sample preparation protocol, enables analysis of large volumes of water (e.g., 10-20 mL) for automated detection and enumeration of Giardia cysts in ~1 hour, including all the steps of sample preparation and analysis. We evaluated the performance of this approach using flow-cytometer-enumerated Giardia-contaminated water samples, demonstrating an average cyst capture efficiency of ~79% on our filter membrane along with a machine learning based cyst counting sensitivity of ~84%, yielding a limit-of-detection of ~12 cysts per 10 mL. Providing rapid detection and quantification of microorganisms, this field-portable imaging and sensing platform running on a mobile-phone could be useful for water quality monitoring in field and resource-limited settings.
Left ventricular (LV) circumferential strain (Ecc) is a sensitive index of regional myocardial function. Currently, no studies have assessed its prognostic value in general population. We sought to ...investigate whether Ecc has a prognostic value for predicting incident heart failure (HF) and other major cardiovascular events in asymptomatic individuals without a history of previous cardiovascular diseases.
We, prospectively, assessed incident HF and atherosclerotic events during a 5.5 ± 1.3-year period in 1768 asymptomatic individuals aged 45-84 (mean age 65 years; 47% female) who underwent tagged magnetic resonance imaging for strain determination. During the follow-up period, 39 (2.2%) participants experienced incident HF and 108 (6.1%) participants had atherosclerotic cardiovascular events. Average of peak Ecc of 12-LV segments (Ecc-global) and mid-slice (Ecc-mid) was -17.0 ± 2.4 and -17.5 ± 2.7%, respectively. Participants with average absolute Ecc-mid lower than -16.9% had a higher cumulative hazard of incident HF (log-rank test, P = 0.001). In cox regression analysis, Ecc-mid predicted incident HF independent of age, diabetes status, hypertension, interim myocardial infarction, LV mass index, and LV ejection fraction (hazard ratio 1.15 per 1%, 95% CI: 1.01-1.31, P = 0.03). This relationship remained significant after adjustment for LV-end-systolic wall stress into covariates. In addition, by adding Ecc-mid to risk factors, LV ejection fraction, and the LV mass index, both the global χ(2) value (76.6 vs. 82.4, P = 0.04) and category-less net-reclassification index (P = 0.01, SE = 0.18, z = 2.53) were augmented for predicting HF. Circumferential strain was also significantly related to the composite atherosclerotic cardiovascular events, but its relationship was attenuated after introducing the LV mass index.
Circumferential shortening provides robust, independent, and incremental predictive value for incident HF in asymptomatic subjects without any history of previous clinical cardiovascular disease.
http://www.clinicaltrials.gov. Unique identifier: NCT00005487.
The predictive value of ascending aortic distensibility (AAD) for mortality and hard cardiovascular disease (CVD) events has not been fully established.
This study sought to assess the utility of AAD ...to predict mortality and incident CVD events beyond conventional risk factors in MESA (Multi-Ethnic Study of Atherosclerosis).
AAD was measured with magnetic resonance imaging at baseline in 3,675 MESA participants free of overt CVD. Cox proportional hazards regression was used to evaluate risk of death, heart failure (HF), and incident CVD in relation to AAD, CVD risk factors, indexes of subclinical atherosclerosis, and Framingham risk score.
There were 246 deaths, 171 hard CVD events (myocardial infarction, resuscitated cardiac arrest, stroke and CV death), and 88 HF events over a median 8.5-year follow-up. Decreased AAD was associated with increased all-cause mortality with a hazard ratio (HR) for the first versus fifth quintile of AAD of 2.7 (p = 0.008) independent of age, sex, ethnicity, other CVD risk factors, and indexes of subclinical atherosclerosis. Overall, patients with the lowest AAD had an independent 2-fold higher risk of hard CVD events. Decreased AAD was associated with CV events in low to intermediate- CVD risk individuals with an HR for the first quintile of AAD of 5.3 (p = 0.03) as well as with incident HF but not after full adjustment.
Decreased proximal aorta distensibility significantly predicted all-cause mortality and hard CV events among individuals without overt CVD. AAD may help refine risk stratification, especially among asymptomatic, low- to intermediate-risk individuals.
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