Batch fabrication of flowable colorimetric pressure sensing particles via surface micromachining

Journal ArticleThe batch fabrication and test of artificial optical resonator slab-type micro particles (14 μm diameter, 0.7 μm gap) is presented as a means to map absolute pressure within microscopic environments. The pressure-sensing particles consist of a semi-transparent elastic polysilicon shell enclosing a reference vacuum cavity. The optical resonance frequency and the corresponding external pressure can hence be interrogated optically via reflectivity measurements. We demonstrate the measurement of internal pressures between 0-20 psi within microfluidic environments

Activated recombinant factor VIIa should not be used in patients with refractory variceal bleeding: it is mostly ineffective, is expensive, and may rarely cause serious adverse events

Activated Recombinant Factor VIIa Does Not Improve Mortality in Variceal Bleeding. Bendtsen F, D’Amico G, Rusch E, de Franchis R, Anderson PK, Lebrec D, et al. Effect of recombinant Factor VIIa on outcome of acute variceal bleeding: An individual patient based meta-analysis of two controlled trials. J Hepatol 2014; 61: 252–259. (Reproduced with Permission) BACKGROUND & AIMS: Two randomized controlled studies have evaluated the effect of recombinant Factor VIIa (rFVIIa) on variceal bleeding in cirrhosis without showing significant benefit. The aim of the present study was to perform a meta-analysis of the two trials on individual patient data with special focus on high risk patients. METHODS: The primary outcome measure was the effect of rFVIIa on a composite five day endpoint: failure to control bleeding, 5-day rebleeding or death. Analysis was based on intention to treat. High risk was defined as active bleeding on endoscopy while under vasoactive drug infusion and Child-Pugh score >8. RESULTS: 497 patients were eligible for the meta-analysis; 308 (62%) had active variceal bleeding at endoscopy (oozing or spurting) and 283 of these had a Child-Pugh score >8. Analysis on the composite endpoint in all patients with bleeding from oesophageal varices did not show any beneficial treatment effect. However, failure rate for the primary composite end-point was significantly lower in treated patients with active bleeding at endoscopy (17%) compared to placebo (26%, p = 0.049). This difference was highly significant in patients with Child-Pugh score >8 and active bleeding at endoscopy (rFVIIa 16%, placebo 27%; p = 0.023). No significant treatment effect was found at 42 days. Five thromboembolic events occurred in rFVIIa treated patients compared to none in placebo treated patients. CONCLUSIONS: The current meta-analysis shows a beneficial effect of rFVIIa on the primary composite endpoint of control of acute bleeding, prevention of rebleeding day 1–5 and 5-day mortality in patients with advanced cirrhosis and active bleeding from oesophageal varices at endoscopy. A major drawback of the treatment is a potential increased risk of arterial thrombo-embolic events. This treatment might be considered in patients with lack of control of bleeding after standard treatment

A voltage limiter circuit for indoor light energy harvesting applications

A voltage limiter circuit for indoor light energy harvesting applications is presented. This circuit is a part of a bigger system, whose function is to harvest indoor light energy, process it and store it, so that it can be used at a later time. This processing consists on maximum power point tracking (MPPT) and stepping-up, of the voltage from the photovoltaic (PV) harvester cell. The circuit here described, ensures that even under strong illumination, the generated voltage will not exceed the limit allowed by the technology, avoiding the degradation, or destruction, of the integrated die. A prototype of the limiter circuit was designed in a 130 nm CMOS technology. The layout of the circuit has a total area of 23414 mu m(2). Simulation results, using Spectre, are presented

Trends in Characteristics, Mortality, and Other Outcomes of Patients With Newly Diagnosed Cirrhosis

Importance: Changes in the characteristics of patients with cirrhosis are likely to affect future outcomes and are important to understand in planning for the care of this population. Objective: To identify changes in demographic and clinical characteristics and outcomes in patients with newly diagnosed cirrhosis. Design, Setting, and Participants: A retrospective cohort study of patients with a new diagnosis of cirrhosis was conducted using the Indiana Network for Patient Care, a large statewide regional health information exchange, between 2004 and 2014. Patients with at least 1 year of continuous follow-up before the cirrhosis diagnosis were followed up through August 1, 2015. The analysis was conducted from December 2018 to January 2019. Exposures: Age, cause of cirrhosis, and year of diagnosis. Main Outcomes and Measures: Overall rates for mortality, liver transplant, hepatocellular carcinoma, and hepatic decompensation (composite of ascites, hepatic encephalopathy, or variceal bleeding). Results: A total of 9261 patients with newly diagnosed cirrhosis were identified (mean [SD] age, 57.9 [12.6] years; 5109 [55.2%] male). A 69% increase in new diagnoses occurred over the course of the study period (620 in 2004 vs 1045 in 2014). The proportion of those younger than 40 years increased by 0.20% per year (95% CI, 0.04% to 0.36%; P for trend = .02), and the proportion of those aged 65 years and older increased by 0.81% per year (95% CI, 0.51% to 1.11%; P for trend < .001). The proportion of patients with alcoholic cirrhosis increased by 0.80% per year (95% CI, 0.49% to 1.12%), and the proportion with nonalcoholic steatohepatitis increased by 0.59% per year (95% CI, 0.30% to 0.87%), whereas the proportion with viral hepatitis decreased by 1.36% per year (95% CI, -1.68% to -1.03%) (P < .001 for all). In patients younger than 40 years, 40 to 64 years, and 65 years and older, mortality rates were 6.4 (95% CI, 5.4 to 7.6), 9.9 (95% CI, 9.5 to 10.4), and 16.2 (95% CI, 15.2 to 17.2) per 100 person-years, respectively (P < .001). Mortality rates decreased during the study period (11.9 [95% CI, 10.7-13.1] per 100 person-years in 2004 vs 10.0 [95% CI, 8.1-12.2] per 100 person-years in 2014; annual adjusted hazard ratio, 0.87 [95% CI, 0.86 to 0.88]) and were lower in those with alcoholic cirrhosis compared with patients with viral hepatitis (adjusted hazard ratio, 0.89 [95% CI, 0.80 to 0.98]). Rates of hepatocellular carcinoma were low in patients younger than 40 years (0.5 [95% CI, 0.2 to 0.9] per 100 person-years). Liver transplant rates were low throughout the study period (0.3 [95% CI, 0.3-0.4] per 100 person-years). In patients with compensated cirrhosis, rates of hepatic decompensation were lower in patients younger than 40 years (adjusted subhazard ratio 0.78; 95% CI, 0.62 to 0.99) and in patients with nonalcoholic steatohepatitis (adjusted subhazard ratio, 0.51; 95% CI, 0.43 to 0.60). Conclusions and Relevance: The population of patients with newly diagnosed cirrhosis in Indiana has experienced changes in the age distribution and cause of cirrhosis, with decreasing mortality rates. These findings support investment in the prevention and treatment of alcoholic liver disease and nonalcoholic steatohepatitis, particularly in younger and older patients. Additional study is needed to identify the reasons for decreasing mortality rates

Alcohol Abstinence Does Not Fully Reverse Abnormalities of Mucosal-Associated Invariant T Cells in the Blood of Patients With Alcoholic Hepatitis

OBJECTIVES: Alcoholic hepatitis (AH) develops in approximately 30% of chronic heavy drinkers. The immune system of patients with AH is hyperactivated, yet ineffective against infectious diseases. Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that are highly enriched in liver, mucosa, and peripheral blood and contribute to antimicrobial immunity. We aimed to determine whether MAIT cells were dysregulated in heavy drinkers with and without AH and the effects of alcohol abstinence on MAIT cell recovery. METHODS: MR1 tetramers loaded with a potent MAIT cell ligand 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil were used in multiparameter flow cytometry to analyze peripheral blood MAIT cells in 59 healthy controls (HC), 56 patients with AH, and 45 heavy drinkers without overt liver disease (HDC) at baseline and 6- and 12-month follow-ups. Multiplex immunoassays were used to quantify plasma levels of cytokines related to MAIT cell activation. Kinetic Turbidimetric Limulus Amebocyte Lysate Assay and ELISA were performed to measure circulating levels of 2 surrogate markers for bacterial translocation (lipopolysaccharide and CD14), respectively. RESULTS: At baseline, patients with AH had a significantly lower frequency of MAIT cells than HDC and HC. HDC also had less MAIT cells than HC (median 0.16% in AH, 0.56% in HDC, and 1.25% in HC). Further, the residual MAIT cells in patients with AH expressed higher levels of activation markers (CD69, CD38, and human leukocyte antigen [HLA]-DR), the effector molecule granzyme B, and the immune exhaustion molecule PD-1. Plasma levels of lipopolysaccharide and CD14 and several cytokines related to MAIT cell activation were elevated in patients with AH (interferon [IFN]-α, interleukin [IL]-7, IL-15, IL-17, IL-18, IL-23, IFN-γ, and tumor necrosis factor α). Decreased MAIT cell frequency and upregulated CD38, CD69, and HLA-DR correlated negatively and positively, respectively, with aspartate aminotransferase level. MAIT cell frequency negatively correlated with IL-18. HLA-DR and CD38 levels correlated with several cytokines. At follow-ups, abstinent patients with AH had increased MAIT cell frequency and decreased MAIT cell activation. However, MAIT cell frequency was not fully normalized in patients with AH (median 0.31%). DISCUSSION: We showed that HDC had a reduction of blood MAIT cells despite showing little evidence of immune activation, whereas patients with AH had a severe depletion of blood MAIT cells and the residual cells were highly activated. Alcohol abstinence partially reversed those abnormalities

Poor Performance Status is Associated with Increased Mortality in Patients with Cirrhosis

Background & Aims Functional status (a patient’s ability to perform activities that meet basic needs, fulfill usual roles, and maintain health and well being) has been linked to outcomes in patients with cirrhosis and can be measured by the Karnofsky performance status (KPS) scale. We investigated the association between KPS score and mortality in patients with cirrhosis. Methods We used the United Network for Organ Sharing database to perform a retrospective cohort study of patients listed for liver transplantation in the United States between 2005 and 2015. We used Cox proportional hazards and competing risk regression analyses to examine the association between KPS and mortality and transplantation. Results Of 79,092 patients, 44% were in KPS category A (KPS 80%–100%), 43% were in category B (KPS 50%–70%), and 13% were in category C (KPS 10%–40%). Between 2005 and 2015, the proportion of patients in category A decreased from 53% to 35%, whereas the proportions in categories B and C increased from 36% to 49% and from 11% to 16%, respectively. KPS was associated with mortality: compared to patients in KPS category A, the KPS B adjusted hazard ratio [HR] was 1.14 (95% confidence interval [CI], 1.11–1.18) and the KPS C adjusted HR was 1.63 (95% CI, 1.55–1.72). KPS was also associated with liver transplantation; compared to patients in KPS category A, the KPS B adjusted HR was 1.08 (95% CI, 1.06–1.11) and the KPS C adjusted HR was 1.35 (95% CI, 1.30–1.40). In competing risk analysis, only the relationship between KPS and mortality maintained significance and directionality. These relationships were most pronounced in patients without hepatocellular carcinoma. Conclusions Among patients with cirrhosis listed for liver transplantation, poor performance status, based on the KPS scale, is associated with increased mortality. In this population, performance status has decreased over time

Signal transducer and activator of transcription 2 deficiency is a novel disorder of mitochondrial fission

Defects of mitochondrial dynamics are emerging causes of neurological disease. In two children presenting with severe neurological deterioration following viral infection we identified a novel homozygous STAT2 mutation, c.1836C4A (p.Cys612Ter), using whole exome sequencing. In muscle and fibroblasts from these patients, and a third unrelated STAT2-deficient patient, we observed extremely elongated mitochondria. Western blot analysis revealed absence of the STAT2 protein and that the mitochondrial fission protein DRP1 (encoded by DNM1L) is inactive, as shown by its phosphorylation state. All three patients harboured 15 decreased levels of DRP1 phosphorylated at serine residue 616 (P-DRP1S616), a post-translational modification known to activate DRP1, and increased levels of DRP1 phosphorylated at serine 637 (P-DRP1S637), associated with the inactive state of the DRP1 GTPase. Knockdown of STAT2 in SHSY5Y cells recapitulated the fission defect, with elongated mitochondria and decreased PDRP1 S616 levels. Furthermore the mitochondrial fission defect in patient fibroblasts was rescued following lentiviral transduction with wild-type STAT2 in all three patients, with normalization of mitochondrial length and increased P-DRP1S616 levels. Taken 20 together, these findings implicate STAT2 as a novel regulator of DRP1 phosphorylation at serine 616, and thus of mitochondrial fission, and suggest that there are interactions between immunity and mitochondria. This is the first study to link the innate immune system to mitochondrial dynamics and morphology. We hypothesize that variability in JAK-STAT signalling may contribute to the phenotypic heterogeneity of mitochondrial disease, and may explain why some patients with underlying mitochondrial disease decompensate after seemingly trivial viral infections. Modulating JAK-STAT activity may represent a novel 25 therapeutic avenue for mitochondrial diseases, which remain largely untreatable. This may also be relevant for more common neurodegenerative diseases, including Alzheimer’s, Huntington’s and Parkinson’s diseases, in which abnormalities of mitochondrial morphology have been implicated in disease pathogenesis

Strain in epitaxial MnSi films on Si(111) in the thick film limit studied by polarization-dependent extended x-ray absorption fine structure

We report a study of the strain state of epitaxial MnSi films on Si(111) substrates in the thick film limit (100-500~\AA) as a function of film thickness using polarization-dependent extended x-ray absorption fine structure (EXAFS). All films investigated are phase-pure and of high quality with a sharp interface between MnSi and Si. The investigated MnSi films are in a thickness regime where the magnetic transition temperature $T_\mathrm{c}$ assumes a thickness-independent enhanced value of $\geq$43~K as compared with that of bulk MnSi, where $T_\mathrm{c} \approx 29~{\rm K}$. A detailed refinement of the EXAFS data reveals that the Mn positions are unchanged, whereas the Si positions vary along the out-of-plane [111]-direction, alternating in orientation from unit cell to unit cell. Thus, for thick MnSi films, the unit cell volume is essentially that of bulk MnSi --- except in the vicinity of the interface with the Si substrate (thin film limit). In view of the enhanced magnetic transition temperature we conclude that the mere presence of the interface, and its specific characteristics, strongly affects the magnetic properties of the entire MnSi film, even far from the interface. Our analysis provides invaluable information about the local strain at the MnSi/Si(111) interface. The presented methodology of polarization dependent EXAFS can also be employed to investigate the local structure of other interesting interfaces.Comment: 11 pages, 10 figure

Hospital Readmissions in Patients with Cirrhosis: A Systematic Review

BACKGROUND: Hospital readmission is a significant problem for patients with complex chronic illnesses such as liver cirrhosis. PURPOSE: We aimed to describe the range of readmission risk in patients with cirrhosis and the impact of the model for end-stage liver disease (MELD) score. DATA SOURCES: We conducted a systematic review of studies identified in Ovid MEDLINE, PubMed, EMBASE, CINAHL, the Cochrane Library, Scopus, Google Scholar, and ClinicalTrials.gov from 2000 to May 2017. STUDY SELECTION: We examined studies that reported early readmissions (up to 90 days) in patients with cirrhosis. Studies were excluded if they did not examine the association between readmission and at least 1 variable or intervention. DATA EXTRACTION: Two reviewers independently extracted data on study design, setting, population, interventions, comparisons, and detailed information on readmissions. DATA SYNTHESIS: Of the 1363 records reviewed, 26 studies met the inclusion and exclusion criteria. Of these studies, 21 were retrospective, and there was significant variation in the inclusion and exclusion criteria. The pooled estimate of 30-day readmissions was 26%(95% confidence interval [CI], 22%-30%). Few studies examined readmission preventability or the relationship between readmissions and social determinants of health. Reasons for readmission were highly variable. An increased MELD score was associated with readmissions in most studies. Readmission was associated with increased mortality. CONCLUSIONS: Hospital readmissions frequently occur in patients with cirrhosis and are associated with liver disease severity. The impact of functional and social factors on readmissions is unclear

A DC-DC Step-Up mu-Power Converter for Energy Harvesting Applications, Using Maximum Power PointTracking, Based on Fractional Open Circuit Voltage

A DC-DC step-up micro power converter for solar energy harvesting applications is presented. The circuit is based on a switched-capacitorvoltage tripler architecture with MOSFET capacitors, which results in an, area approximately eight times smaller than using MiM capacitors for the 0.131mu m CMOS technology. In order to compensate for the loss of efficiency, due to the larger parasitic capacitances, a charge reutilization scheme is employed. The circuit is self-clocked, using a phase controller designed specifically to work with an amorphous silicon solar cell, in order to obtain themaximum available power from the cell. This will be done by tracking its maximum power point (MPPT) using the fractional open circuit voltage method. Electrical simulations of the circuit, together with an equivalent electrical model of an amorphous silicon solar cell, show that the circuit can deliver apower of 1132 mu W to the load, corresponding to a maximum efficiency of 66.81%