Biodistribution Analysis of Peptide-Coated Magnetic Iron Nanoparticles: A Simple and Quantitative Method

Biodistribution tracks compounds or molecules of interest in vivo to understand a compound's anticipated efficacy and safety. Nanoparticles deliver nucleic acid and drug payloads and enhance tumor permeability due to multiple properties such as high surface area to volume ratio, surface functionalization, and modifications. Studying the in vivo biodistribution of nanoparticles documents the effectiveness and safety of nanoparticles and facilitates a more application-driven approach for nanoparticle development that allows for more successful translation into clinical use. In this study, we present a relatively simple method to determine the biodistribution of magnetic iron nanoparticles in mice. In vitro, cells take up branched amphiphilic peptide-coated magnetic nanobeads (BAPc-MNBs) like their counterparts, i.e., branched amphiphilic peptide capsules (BAPCs) with a hollow water-filled core. Both BAPc-MNBs and BAPCs have widespread applications as a nanodelivery system. We evaluated the BAPc-MNBs tissue distribution in wild-type mice injected intravenously (i.v.), intraperitoneally (i.p.), or orally gavaged to understand the biological interactions and to further the development of branched amphiphilic peptide-based nanoparticles. The magnetic nanoparticles allowed collection of the BAPc-MNBs from multiple organs by magnetic bead sorting, followed by a high-throughput screening for iron content. When injected i.v., nanoparticles were distributed widely to various organs before elimination from the system via the intestines in feces. The spleen accumulated the highest amount of BAPc-MNBs in mice administered NPs via i.v. and i.p. but not via oral gavage. Taken together, these data demonstrate that the magnetic sorting not only allowed quantification of the BAPc-MNBs but also identified the distribution of BAPc-MNBs after distinct administration methods.

Biodistribution Analysis of Peptide-Coated Magnetic Iron Nanoparticles: A Simple and Quantitative Method

Biodistribution is the tracking of compounds or molecules of interest in the subject which is integral to understanding their anticipated efficacy and safety. Nanoparticles are highly desirable delivery systems which have the ability to deliver higher nucleic acid and drug payloads and they have enhanced tumor permeability due to their unique properties such as high surface area to volume ratio. Studying the biodistribution of nanoparticles is crucial to understand their effectiveness and safety in vivo, facilitate a more application driven approach for nanoparticle development which will lead to their successful translation into clinical use. In this study, we present a relatively simple method to determine the biodistribution of magnetic iron nanoparticles in mice. Branched Amphiphilic Peptide coated Magnetic Nanobeads BAPc-MNBs like their counterpart i.e., Branched Amphiphilic Peptide capsules (BAPCs) with a hollow water-filled core, are readily taken up by cells in vitro and have widespread application as a nanodelivery systems. We evaluated the BAPc-MNBs tissue distribution in wildtype mice injected intravenously (i.v.), intraperitoneally (i.p.) or orally gavaged to understand the biological interactions of the peptide nanoparticles and to further the development of branched amphiphilic peptides-based nanoparticles. BAPc-MNBs were distributed widely to various organs when injected i.v. and were eliminated from the system via the intestines in feces. The spleen was found to accumulate the highest amount of BAPc-MNBs in mice administered the NPs i.v. and i.p. while they were not absorbed into the system via oral gavage. This study not only presents a relatively simple quantification method to determine in vivo biodistribution of magnetic iron nanoparticles that can be widely applied but also demonstrates the potential of Branched Amphiphilic Peptides in the form of BAPCs or BAPc-MNBs as a delivery system.

Transcriptomic analyses of joint tissues during osteoarthritis development in a rat model reveal dysregulated mechanotransduction and extracellular matrix pathways

OBJECTIVE

Transcriptomic changes in joint tissues during the development of osteoarthritis (OA) are of interest for the discovery of biomarkers and mechanisms of disease. The objective of this study was to use the rat medial meniscus transection (MMT) model to discover stage and tissue-specific transcriptomic changes.

DESIGN

Sham or MMT surgeries were performed in mature rats. Cartilage, menisci and synovium were scored for histopathological changes at 2, 4 and 6 weeks post-surgery and processed for RNA-sequencing. Differentially expressed genes (DEG) were used to identify pathways and mechanisms. Published transcriptomic datasets from animal models and human OA were used to confirm and extend present findings.

RESULTS

The total number of DEGs was already high at 2 weeks (723 in meniscus), followed by cartilage (259) and synovium (42) and declined to varying degrees in meniscus and synovium but increased in cartilage at 6 weeks. The most upregulated genes included tenascins. The 'response to mechanical stimulus' and extracellular matrix-related pathways were enriched in both cartilage and meniscus. Pathways that were enriched in synovium at 4 weeks indicate processes related to synovial hyperplasia and fibrosis. Synovium also showed upregulation of IL-11 and several MMPs. The mechanical stimulus pathway included upregulation of the mechanoreceptors PIEZO1, PIEZO2 and TRPV4 and nerve growth factor. Analysis of data from prior RNA-sequencing studies of animal models and human OA support these findings.

CONCLUSION

These results indicate several shared pathways that are affected during OA in cartilage and meniscus and support the role of mechanotransduction and other pathways in OA pathogenesis.

Coexistent diabetes is associated with the presence of adverse phenotypic features in patients with hypertrophic cardiomyopathy

Background

Type 2 diabetes mellitus (DM) is associated with worsened clinical outcomes in hypertrophic cardiomyopathy (HCM) patients. The reasons for this adverse prognostic association are incompletely understood. Although distinct entities both HCM and DM share common features of impaired myocardial energetics and coronary microvascular function.

Purpose

We sought to test the hypothesis that co-existent diabetes is associated with greater reductions in myocardial energetics and perfusion, and higher scar burden in HCM.

Research design and methods

Seventy-five age- and sex-matched participants with concomitant HCM and DM (HCM-DM, n=20), isolated HCM (n=20), isolated DM (n=20) and healthy volunteers (HV, n=15) underwent 31phosphorus magnetic resonance spectroscopy and cardiovascular magnetic resonance imaging. The HCM groups were matched for HCM phenotype. The DM groups were matched for diabetes treatment, duration, HbA1c, body mass index and hypertension comorbidity.

Results

ESC sudden cardiac death risk scores were comparable between the HCM groups (HCM: 2.2±1.5%, HCM-DM: 1.9±1.2%; p=NS) and sarcomeric mutations were equally common. HCM-DM had the highest NT-proBNP levels (HV: 42 ng/L [IQR: 35–66], DM: 118 ng/L [IQR: 53–187], HCM: 298 ng/L [IQR: 157–837], HCM-DM: 726 ng/L [IQR: 213–8695]; p<0.0001). Left-ventricular ejection fraction, mass and wall thickness were similar between the HCM groups. HCM-DM displayed a greater degree of fibrosis burden with higher scar percentage, and lower global longitudinal strain compared to the isolated HCM. PCr/ATP was similarly decreased in the HCM-DM and DM (HV: 2.17±0.49, DM: 1.61±0.23, HCM: 1.93±0.38, HCM-DM: 1.54±0.27; p=0.0003). HCM-DM had the lowest stress myocardial blood flow (HV: 2.06±0.42 ml/min/g, DM: 1.78±0.45 ml/min/g, HCM: 1.74±0.44 ml/min/g, HCM-DM: 1.39±0.42 ml/min/g; p=0.004).

Conclusions

We show for the first time that HCM patients with DM comorbidity display greater reductions in myocardial energetics, perfusion, contractile function and higher myocardial scar burden and serum NT-proBNP levels compared to patients with isolated HCM despite similar LV mass and wall thickness and presence of sarcomeric mutations. These adverse phenotypic features may be important components of the adverse clinical manifestation attributable to a combined presence of HCM and DM.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Diabetes UK

Factors Associated With Severe Illness in Patients Aged <21 Years Hospitalized for COVID-19

OBJECTIVES

To describe coronavirus disease 2019 (COVID-19)-related pediatric hospitalizations during a period of B.1.617.2 (Δ) variant predominance and to determine age-specific factors associated with severe illness.

METHODS

We abstracted data from medical charts to conduct a cross-sectional study of patients aged <21 years hospitalized at 6 United States children's hospitals from July to August 2021 for COVID-19 or with an incidental positive severe acute respiratory syndrome coronavirus 2 test. Among patients with COVID-19, we assessed factors associated with severe illness by calculating age-stratified prevalence ratios (PR). We defined severe illness as receiving high-flow nasal cannula, positive airway pressure, or invasive mechanical ventilation.

RESULTS

Of 947 hospitalized patients, 759 (80.1%) had COVID-19, of whom 287 (37.8%) had severe illness. Factors associated with severe illness included coinfection with respiratory syncytial virus (RSV) (PR 3.64) and bacteria (PR 1.88) in infants; RSV coinfection in patients aged 1 to 4 years (PR 1.96); and obesity in patients aged 5 to 11 (PR 2.20) and 12 to 17 years (PR 2.48). Having ≥2 underlying medical conditions was associated with severe illness in patients aged <1 (PR 1.82), 5 to 11 (PR 3.72), and 12 to 17 years (PR 3.19).

CONCLUSIONS

Among patients hospitalized for COVID-19, factors associated with severe illness included RSV coinfection in those aged <5 years, obesity in those aged 5 to 17 years, and other underlying conditions for all age groups <18 years. These findings can inform pediatric practice, risk communication, and prevention strategies, including vaccination against COVID-19.

Coexistent Diabetes Is Associated With the Presence of Adverse Phenotypic Features in Patients With Hypertrophic Cardiomyopathy

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is associated with worsened clinical outcomes in hypertrophic cardiomyopathy (HCM) patients. We sought to investigate whether HCM patients with T2DM comorbidity exhibit adverse cardiac alterations in myocardial energetics, function, perfusion, or tissue characteristics.

RESEARCH DESIGN AND METHODS

A total of 55 participants with concomitant HCM and T2DM (HCM-DM) (n = 20) or isolated HCM (n = 20) and healthy volunteers (HV) (n = 15) underwent 31P-MRS and cardiovascular MRI. The HCM groups were matched for HCM phenotype.

RESULTS

Mean ± SD European Society of Cardiology sudden cardiac death risk scores were comparable between the HCM groups (HCM 2.2 ± 1.5%, HCM-DM 1.9 ± 1.2%; P = not significant), and sarcomeric mutations were equally common. HCM-DM patients had the highest median NT-proBNP levels (HV 42 ng/L [interquartile range 35-66], HCM 298 ng/L [157-837], HCM-DM 726 ng/L [213-8,695]; P < 0.0001). Left ventricular (LV) ejection fraction, mass, and wall thickness were similar between the HCM groups. HCM-DM patients displayed a greater degree of fibrosis burden with higher scar percentage and lower global longitudinal strain compared with HCM patients. PCr/ATP (the relative concentrations of phosphocreatine and ATP) was significantly lower in the HCM-DM group than in both HCM and HV (HV 2.17 ± 0.49, HCM 1.93 ± 0.38, HCM-DM 1.54 ± 0.27; P = 0.002). In a similar pattern, stress myocardial blood flow was significantly lower in the HCM-DM group than in both HCM and HV (HV 2.06 ± 0.42 mL/min/g, HCM 1.74 ± 0.44 mL/min/g, HCM-DM 1.39 ± 0.42 mL/min/g; P = 0.002).

CONCLUSIONS

We show for the first time that HCM-DM patients display greater reductions in myocardial energetics, perfusion, and contractile function and higher myocardial scar burden and serum NT-proBNP levels compared with patients with isolated HCM despite similar LV mass and wall thickness and presence of sarcomeric mutations. These adverse phenotypic features may be important components of the adverse clinical manifestation attributable to a combined presence of HCM and T2DM.

Inhibition of novel lipoprotein(a) receptor major facilitator superfamily domain containing 5 (MFSD5) reduces development of aortic valve calcification

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Private grant from Kowa Pharmaceuticals to Brigham and Woman's Hospital

Calcific aortic valve stenosis (CAVS) is the most prevent valvular heart disease in the western world increasing exponentially with age, with an 112% increase in CAVS deaths in the last three decades; however no therapeutic treatment is currently available. Recently, lipoprotein(a) [Lp(a)] has been demonstrated to be an independent and causal risk factor for CAVS, yet the understanding of its cellular uptake and catabolism is limited thus underscoring the need for further investigation.

This study aimed to determine a target receptor, unique for Lp(a) on the surface of valvular interstitial cells (VICs) and ascertain the role of the receptor on the development of VIC calcification.

Unbiased ligand-receptor capture mass spectrometry (TriCEPS) was used to identify target receptor, with western blotting, ELISA, qPCR, alizarin red calcium staining and immunofluorescence used to validate the targets in vitro via siRNA inhibition and overexpression. Transmission electron microscopy (TEM) was used to determine uptake of Lp(a) within excised human valves. Identification of small molecule inhibitors was assessed computationally via the L1000 dataset, with the top hit candidate validated in vitro. Genotype-phenotype studies were examined using the United Kingdom Biobank (UKBB) and the Millions Veterans Program. Linear regression was used to evaluate association between aortic stenosis and plasma Lp(a) levels, and a phenotype-wide association analysis was then performed against this generated ‘genotype’.

Ligand-receptor capture mass spectrometry was used to detect novel membrane proteins with specific binding to Lp(a); MFSD5, MRC2, LDLR were identified as possible candidates. MFSD5 RNAscope demonstrated its presence in human aortic valves. Lp(a) uptake in VICs was confirmed via western blot and TEM. MFSD5 siRNA significantly reduced dil-labelled Lp(a) uptake in human VICs (p=0.003) and HEPG2 cells (p=0.0003), conversely MFSD5 overexpression increased uptake (p=0.0345, p=0.0318), whilst specificity of MFSD5 to Lp(a) alone was shown via no change in LDL uptake following MFSD5 inhibition (p=0.616, p=0.991). MFSD5 inhibition reduced RUNX2 (p=0.0124) and Osteocalcin (p&lt;0.001) RNA expression and reduced alizarin red staining following culture in Lp(a) osteogenic media for 21 days (p&lt;0.0033). Druggability of MFSD5 was confirmed by the L1000 database, which identified aminopurvalanol as a binding partner for MFSD5 and significantly reduced Lp(a) uptake within VICs (p=0.0091). MFSD5-loss of function within the UKBB showed no significant cardiovascular association, however 50kb +/- of the MFSD5 gene showed nominal association with hyperlipidaemia and atrial fibrillation.

The current study demonstrates the novel Lp(a) receptor MFSD5 may be responsible for uptake of Lp(a) within VICs, resulting in the development of aortic valve calcification, highlighting the need for further exploration into the role of MFSD5 in aortic valve disease.

Donor-derived Cryptococcus gattii sensu stricto infection in two kidney transplant recipients, southeastern United States

Cryptococcus gattii infection is a rare cause of severe pulmonary disease and meningoencephalitis that has only recently been detected in the southeastern United States. We describe an organ transplant-associated outbreak of C. gattii infection involving an HIV-negative immunosuppressed donor in this region who died following new-onset headache and seizure of unknown cause. Retrospective cryptococcal antigen (CrAg) testing of donor serum was positive. Two of the three transplant recipients developed severe C. gattii infection 11 and 12 weeks following transplantation. One recipient died from severe pulmonary infection, identified on autopsy, and the other ill recipient survived following treatment for cryptococcal meningitis. This outbreak underscores the importance of considering cryptococcosis in patients with clinical findings suggestive of subacute meningitis or other central nervous system (CNS) pathology, and the potential benefit of routine pre-transplant donor CrAg screening using lateral flow assay to guide recipient antifungal prophylaxis. The case also adds to emerging evidence that C. gattii is a potential threat in the southeastern United States.

Trends in COVID-19 Cases, Emergency Department Visits, and Hospital Admissions Among Children and Adolescents Aged 0-17 Years - United States, August 2020-August 2021

Although COVID-19 generally results in milder disease in children and adolescents than in adults, severe illness from COVID-19 can occur in children and adolescents and might require hospitalization and intensive care unit (ICU) support (1-3). It is not known whether the B.1.617.2 (Delta) variant,* which has been the predominant variant of SARS-CoV-2 (the virus that causes COVID-19) in the United States since late June 2021,^† causes different clinical outcomes in children and adolescents compared with variants that circulated earlier. To assess trends among children and adolescents, CDC analyzed new COVID-19 cases, emergency department (ED) visits with a COVID-19 diagnosis code, and hospital admissions of patients with confirmed COVID-19 among persons aged 0-17 years during August 1, 2020-August 27, 2021. Since July 2021, after Delta had become the predominant circulating variant, the rate of new COVID-19 cases and COVID-19-related ED visits increased for persons aged 0-4, 5-11, and 12-17 years, and hospital admissions of patients with confirmed COVID-19 increased for persons aged 0-17 years. Among persons aged 0-17 years during the most recent 2-week period (August 14-27, 2021), COVID-19-related ED visits and hospital admissions in the states with the lowest vaccination coverage were 3.4 and 3.7 times that in the states with the highest vaccination coverage, respectively. At selected hospitals, the proportion of COVID-19 patients aged 0-17 years who were admitted to an ICU ranged from 10% to 25% during August 2020-June 2021 and was 20% and 18% during July and August 2021, respectively. Broad, community-wide vaccination of all eligible persons is a critical component of mitigation strategies to protect pediatric populations from SARS-CoV-2 infection and severe COVID-19 illness.

Suspected SARS-CoV-2 Reinfections: Incidence, Predictors, and Healthcare Use among Patients at 238 U.S. Healthcare Facilities, June 1, 2020- February 28, 2021

In a retrospective cohort study, among 131,773 patients with previous COVID19, reinfection with SARS-CoV-2 was suspected in 253(0.2%) patients at 238 U.S. healthcare facilities between June 1, 2020- February 28, 2021. Women displayed a higher cumulative reinfection risk. Healthcare burden and illness severity were similar between index and reinfection encounters.

Characteristics and Risk Factors of Hospitalized and Nonhospitalized COVID-19 Patients, Atlanta, Georgia, USA, March-April 2020

We compared the characteristics of hospitalized and nonhospitalized patients who had coronavirus disease in Atlanta, Georgia, USA. We found that risk for hospitalization increased with a patient’s age and number of concurrent conditions. We also found a potential association between hospitalization and high hemoglobin A1c levels in persons with diabetes.

COVID-19 Clinical Phenotypes: Presentation and Temporal Progression of Disease in a Cohort of Hospitalized Adults in Georgia, United States

BACKGROUND

The epidemiological features and outcomes of hospitalized adults with coronavirus disease 2019 (COVID-19) have been described; however, the temporal progression and medical complications of disease among hospitalized patients require further study. Detailed descriptions of the natural history of COVID-19 among hospitalized patients are paramount to optimize health care resource utilization, and the detection of different clinical phenotypes may allow tailored clinical management strategies.

METHODS

This was a retrospective cohort study of 305 adult patients hospitalized with COVID-19 in 8 academic and community hospitals. Patient characteristics included demographics, comorbidities, medication use, medical complications, intensive care utilization, and longitudinal vital sign and laboratory test values. We examined laboratory and vital sign trends by mortality status and length of stay. To identify clinical phenotypes, we calculated Gower's dissimilarity matrix between each patient's clinical characteristics and clustered similar patients using the partitioning around medoids algorithm.

RESULTS

One phenotype of 6 identified was characterized by high mortality (49%), older age, male sex, elevated inflammatory markers, high prevalence of cardiovascular disease, and shock. Patients with this severe phenotype had significantly elevated peak C-reactive protein creatinine, D-dimer, and white blood cell count and lower minimum lymphocyte count compared with other phenotypes (P < .01, all comparisons).

CONCLUSIONS

Among a cohort of hospitalized adults, we identified a severe phenotype of COVID-19 based on the characteristics of its clinical course and poor prognosis. These findings need to be validated in other cohorts, as improved understanding of clinical phenotypes and risk factors for their development could help inform prognosis and tailored clinical management for COVID-19.

Understanding the influence of experimental factors on bio-interactions of nanoparticles: Towards improving correlation between in vitro and in vivo studies

Bionanotechnology has developed rapidly over the past two decades, owing to the extensive and versatile, functionalities and applicability of nanoparticles (NPs). Fifty-one nanomedicines have been approved by FDA since 1995, out of the many NPs based formulations developed to date. The general conformation of NPs consists of a core with ligands coating their surface, that stabilizes them and provides them with added functionalities. The physicochemical properties, especially the surface composition of NPs influence their bio-interactions to a large extent. This review discusses recent studies that help understand the nano-bio interactions of iron oxide and gold NPs with different surface compositions. We discuss the influence of the experimental factors on the outcome of the studies and, thus, the importance of standardization in the field of nanotechnology. Recent studies suggest that with careful selection of experimental parameters, it is possible to improve the positive correlation between in vitro and in vivo studies. This provides a fundamental understanding of the NPs which helps in assessing their potential toxic side effects and may aid in manipulating them further to improve their biocompatibility and biosafety.

Association of premature menopause with incident pulmonary hypertension

Background

Several forms of pulmonary hypertension (PH) disproportionately affect women. Prior animal and human studies suggest that oestradiol exerts mixed effects on the pulmonary vasculature. Whether premature menopause represents a risk factor for PH is currently unknown.

Purpose

To test the independent association of premature menopause with incident PH.

Methods

We included women in the UK Biobank who were 40–69 years old and postmenopausal at enrolment and underwent pulmonary function testing at the baseline study visit. Women with missing menopause data, prevalent PH, extreme pulmonary function test outliers (Z&gt;5 or Z&lt;−5), and those with congenital heart disease were excluded. Premature menopause was defined as occurring before age 40 years. Reproductive history, including age at menopause and use of menopausal hormone therapy (MHT), was ascertained by participant self-report at enrolment. PH risk factors and relevant co-morbidities were captured by participant self-report and by ICD code. Incident PH was ascertained by the appearance of a qualifying ICD code (ICD-9 4160; ICD-10 I27.0, I27.2). Follow-up began at study enrolment, with time to censoring determined by date of PH diagnosis or last encounter in the medical record. Multivariable Cox proportional hazard models tested the association between premature menopause and incident PH, with adjustment for age, race, ever-smoking, body-mass index, systolic blood pressure, antihypertensive medication use, non-high-density lipoprotein cholesterol, cholesterol-lowering medication use, C-reactive protein, prevalent type 2 diabetes, obstructive sleep apnoea, heart failure, venous thromboembolism, mitral regurgitation, aortic stenosis, forced vital capacity (FVC), the forced expiratory volume in 1 second (FEV1)/FVC ratio, and ever-use of MHT.

Results

Among 138,518 postmenopausal women (mean [SD] age at enrolment 60.0 [5.4] years), 5,440 women (3.9%) had a history of premature menopause. Incident PH was diagnosed in 253 women over a median 8.1 (interquartile range 7.4–8.8) years of follow-up. Mean age at menopause was 48.3 (6.4) years among women with incident PH vs. 49.7 (5.1) years among those without PH (P&lt;0.001). Crude cumulative incidence of PH was 0.40% among women premature menopause vs. 0.17% among those without (Figure 1). After multivariable adjustment, premature menopause remained independently associated with PH (hazard ratio [HR] 1.91, 95% CI 1.15–3.16, P=0.01). Ever-use of MHT was not significantly associated with incident PH (HR 0.93, 95% CI 0.68–1.26, P=0.62). In sensitivity analysis excluding 4,461 women with prevalent heart failure, venous thromboembolism, mitral regurgitation, or aortic stenosis, the HR for PH associated with premature menopause was 2.19 (95% CI 1.28–3.74, P=0.004).

Conclusions

Premature menopause is an independent risk factor for PH in women.

Figure 1

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): U.S. National Heart, Lung, and Blood Institute

Predictors at admission of mechanical ventilation and death in an observational cohort of adults hospitalized with COVID-19

Background

Coronavirus disease (COVID-19) can cause severe illness and death. Predictors of poor outcome collected on hospital admission may inform clinical and public health decisions.

Methods

We conducted a retrospective observational cohort investigation of 297 adults admitted to eight academic and community hospitals in Georgia, United States, during March 2020. Using standardized medical record abstraction, we collected data on predictors including admission demographics, underlying medical conditions, outpatient antihypertensive medications, recorded symptoms, vital signs, radiographic findings, and laboratory values. We used random forest models to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CI) for predictors of invasive mechanical ventilation (IMV) and death.

Results

Compared with age <45 years, ages 65–74 years and ≥75 years were predictors of IMV (aOR 3.12, CI 1.47–6.60; aOR 2.79, CI 1.23–6.33) and the strongest predictors for death (aOR 12.92, CI 3.26–51.25; aOR 18.06, CI 4.43–73.63). Comorbidities associated with death (aORs from 2.4 to 3.8, p <0.05) included end-stage renal disease, coronary artery disease, and neurologic disorders, but not pulmonary disease, immunocompromise, or hypertension. Pre-hospital use vs. non-use of angiotensin receptor blockers (aOR 2.02, CI 1.03–3.96) and dihydropyridine calcium channel blockers (aOR 1.91, CI 1.03–3.55) were associated with death.

Conclusions

After adjustment for patient and clinical characteristics, older age was the strongest predictor of death, exceeding comorbidities, abnormal vital signs, and laboratory test abnormalities. That coronary artery disease, but not chronic lung disease, was associated with death among hospitalized patients warrants further investigation, as do associations between certain antihypertensive medications and death.

A Study of the Cellular Uptake of Magnetic Branched Amphiphilic Peptide Capsules

Understanding cellular uptake mechanisms of nanoparticles with therapeutic potential has become critical in the field of drug delivery. Elucidation of cellular entry routes can aid in the dissection of the complex intracellular trafficking and potentially allow for the manipulation of nanoparticle fate after cellular delivery (i.e., avoid lysosomal degradation). Branched amphiphilic peptide capsules (BAPCs) are peptide nanoparticles that have been and are being explored as delivery systems for nucleic acids and other therapeutic molecules in vitro and in vivo. In the present study, we determined the cellular uptake routes of BAPCs with and without a magnetic nanobead core (BAPc-MNBs) in two cell lines: macrophages and intestinal epithelial cells. We also studied the influence of size and growth media composition in this cellular process. Substituting the water-filled core with magnetic nanobeads might provide the peptide bilayer nanocapsules with added functionalities, facilitating their use in bio/immunoassays, magnetic field guided drug delivery, and magnetofection among others. Results suggest that BAPc-MNBs are internalized into the cytosol using more than one endocytic pathway. Flow cytometry and analysis of reactive oxygen and nitrogen species (ROS/RNS) demonstrated that cell viability was minimally impacted by BAPc-MNBs. Cellular uptake pathways of peptide vesicles remain poorly understood, particularly with respect to endocytosis and intracellular trafficking. Outcomes from these studies provide a fundamental understanding of the cellular uptake of this peptide-based delivery system which will allow for strengthening of their delivery capabilities and expanding their applications both in vitro and in vivo.

Maternal hyperglycemia in singleton pregnancies conceived by IVF may be modified by first-trimester BMI

STUDY QUESTION

Does IVF independently increase the risk of gestational diabetes mellitus (GDM) and is this increase in risk modified by maternal body mass index?

SUMMARY ANSWER

IVF appears to be an independent risk factor for GDM and elevated blood glucose levels in overweight women (BMI > 25 kg/m2).

WHAT IS KNOWN ALREADY

IVF has been associated with increased risk of GDM, but most previous studies did not adequately assess confounding or effect modification by other risk factors.

STUDY DESIGN, SIZE, DURATION

Cross-sectional study using data from 1089 women with singleton pregnancies who participated in a Singaporean birth cohort study (GUSTO) and received a 75 g oral glucose tolerance test (OGTT) at 26-28 weeks gestation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

A total of 1089 women (n = 1013 conceived spontaneously, n = 76 conceived through IVF) with singleton pregnancies received a 75 g OGTT at 26-28 weeks gestation. Fasting and 2 h postprandial blood glucose levels were assayed. World Health Organization criteria (1999) standard criteria were used to classify GDM: ≥7.0 mmol/L for fasting and/or ≥7.8 mmol/L for 2-h postprandial plasma glucose levels, which was the clinical guideline in use during the study.

MAIN RESULTS AND THE ROLE OF CHANCE

IVF pregnancies had nearly double the odds of GDM (OR = 1.83, 95% CI: 1.03-3.26) and elevated fasting (mean difference = 0.12 mmol/L, 95% CI: 0.00-0.24) and OGTT 2-h blood glucose levels (mean difference = 0.64 mmol/L, 95% CI: 0.27-1.01), after adjusting for commonly recognized risk factors for GDM. After stratification by first-trimester BMI, these increased risks of GDM (OR = 3.54, 95% CI: 1.44-8.72) and elevated fasting (mean difference = 0.39 mmol/L, 95% CI: 0.13-0.65) and 2-h blood (mean difference = 1.24 mmol/L, 95% CI: 0.56-1.91) glucose levels were significant only in the IVF group who is also overweight or obese (BMI > 25 kg/m2).

LIMITATIONS REASONS FOR CAUTION

One limitation of our study is the absence of a 1 h post-OGTT plasma glucose sample, as we were using the 1999 WHO diagnostic criteria (the clinical guideline in Singapore) at the time of our study, instead of the revised 2013 WHO diagnostic criteria. Our cohort may not be representative of the general Singapore obstetric population, although participants were recruited from the two largest maternity hospitals in the country and include both private and subsidized patients.

WIDER IMPLICATIONS OF THE FINDINGS

IVF appears to be an independent risk factor for GDM and elevated blood glucose levels in overweight women. Our findings reinforce the need to advise overweight or obese women contemplating IVF to lose weight before the procedure to reduce their risk of GDM and hyperglycemia-related adverse outcomes arising therefrom. In settings where universal GDM screening is not routine, overweight or obese women who conceive by IVF should be screened.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by the Singapore National Research Foundation under its Translational and Clinical Research (TCR) Flagship Program and administered by the Singapore Ministry of Health's National Medical Research Council (NMRC), Singapore (NMRC/TCR/004-NUS/2008; NMRC/TCR/012-NUHS/2014). Additional funding was provided by the Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR). K.M.G. and Y.S.C. have received lecture fees from Nestle Nutrition Institute and Danone, respectively. K.M.G., Y.S.C. and S.Y.C. are part of an academic consortium that has received research funding from Abbott Nutrition, Nestec and Danone. The other authors have nothing to disclose. The other authors have nothing to disclose.

TRIAL REGISTRATION NUMBER

N/A.

The impact of vaccination on RBC alloimmunization in a murine model

Emerging data in animal models and humans suggest that pathogen-associated and damage-associated molecular patterns variably impact RBC alloantibody formation. In this study, we tested the hypothesis that vaccinations may enhance immune responses to transfused RBCs. The Pneumovax23 vaccine decreased the magnitude of anti-KEL alloimmunization in a murine model, whereas the hepB vaccine did not impact the response; RBC transfusion did not alter immune responses to either vaccine. These data highlight the complexities of the intersection of innate and adaptive immunity and suggest that future studies investigating the pathways through which inflammation impacts alloimmunization are warranted.

Split-hand/feet malformation: A rare syndrome

Split-hand/split-foot malformation (SHFM) is mainly inherited as an autosomal dominant trait with incomplete penetrance and characterized by malformation of the limb involving the central rays of the autopod. It presents with a deep median cleft of the hand and/or foot, aplasia/hypoplasia of the phalanges, metacarpals, and metatarsals. Pathogenic mechanism is a failure to maintain signaling from the median apical ectodermal ridge. Without this signaling, cells of the underlying progress zone stop proliferation and differentiation which in turn results in defects of the central rays. We describe a case of SHFM in 10-year-old boy.

Clinically significant anti-KEL RBC alloantibodies are transferred by breast milk in a murine model

BACKGROUND AND OBJECTIVES

Fetuses affected by maternal RBC alloantibodies may have prolonged anaemia after birth, leading one to question whether maternal alloantibody transfer may occur outside the placenta. In response to a recent publication describing breast milk transfer of clinically significant amounts of maternal antiplatelet IgA antibodies from mother to nursing infant, we hypothesized that maternal RBC alloantibodies may also be capable of being transferred in breast milk.

MATERIALS AND METHODS

The presence and clinical significance of breast milk alloantibody transfer were tested through a series of pregnancy, fostering and transfusion experiments, using a murine model in which transgenic RBCs express the human KEL glycoprotein.

RESULTS

Maternal anti-KEL immunoglobulins, induced through transfusion or pregnancy, were detected in the aqueous phase of breast milk. Further, efficient transfer of maternal anti-KEL IgG and IgA to nursing pups was observed in fostering experiments. The breast milk-acquired alloantibodies were clinically significant in wild-type pups in a transfusion setting, binding to 'incompatible' KEL RBCs and leading to premature clearance from the circulation. Although breast milk-acquired alloantibodies also bound to the RBCs of transgenic KEL-positive fostered pups, no anaemia resulted.

CONCLUSIONS

Taking these murine data in combination with recently published human data of maternal antiplatelet IgA antibodies in breast milk leading to sequelae in some infants, it is theoretically possible that maternal anti-RBC IgA alloantibodies may also be transferred in human breast milk and may lead to sequelae in some infants under some circumstances.

The impact of Human Chorionic Gonadotropin (hCG) on growth and food conversion efficiency in Royal Danio, Barilius bakeri Day

In aquaculture, growth hormones attract many researchers as they play a key role in the regulation of body weight and metabolism. In this study, we observed the influence of hCG on growth in Barilius bakeri, a common ornamental fish endemic to the Western Ghats, Kerala, India. Juveniles of B. bakeri 2.19 ± 0.92 g were selected and stocked in the experimental tanks of size 90 x 45 x 45 cm. Water quality parameters were examined periodically and were maintained under tolerable limits. The feeds were formulated at 40% protein level. Different levels of hCG i.e. @ 2.5, 5, 7.5, 10, 12.5 and 15 ppm were tested for both short term and long term. Fishes were fed with experimental diets twice daily at the rate of 5% body weight. Fishes were examined fortnightly and their length and weight documented. Their gross body compositions were also analyzed. The results of the study were subjected to ANOVA using statistical package SPSS version 10.1. Feed incorporated with 12.5 ppm hCG showed the best result in providing percentage gain in length, weight and SGR. The FCE, FAE, PER and protein digestibility values were highest in fishes given feed incorporated with 12.5 ppm hCG.

A case of relapsed visceral Kaposi's sarcoma with bilateral chylothoraces successfully treated with paclitaxel

Chylothorax is a rare complication of visceral Kaposi's sarcoma. We report a case with bilateral chylothoraces secondary to relapsed visceral Kaposi's sarcoma who was successfully treated with paclitaxel chemotherapy.

Immobilization of carbonic anhydrase enzyme purified from Bacillus subtilis VSG-4 and its application as CO(2) sequesterer

The purification, immobilization, and characterization of carbonic anhydrase (CA) secreted by Bacillus subtilis VSG-4 isolated from tropical soil have been investigated in this work. Carbonic anhydrase was purified using ammonium sulfate precipitation, Sephadex-G-75 column chromatography, and DEAE-cellulose chromatography, achieving a 24.6-fold purification. The apparent molecular mass of purified CA obtained by SDS-PAGE was found to be 37 kD. The purified CA was entrapped within a chitosan-alginate polyelectrolyte complex (C-A PEC) hydrogel for potential use as an immobilized enzyme. The optimum pH and temperature for both free and immobilized enzymes were 8.2 and 37°C, respectively. The immobilized enzyme had a much higher storage stability than the free enzyme. Certain metal ions, namely, Co(2+), Cu(2+), and Fe(3+), increased the enzyme activity, whereas CA activity was inhibited by Pb(2+), Hg(2+), ethylenediamine tetraacetic acid (EDTA), 5,5'-dithiobis-(2-nitrobenzoic acid (DTNB), and acetazolamide. Free and immobilized CAs were tested further for the targeted application of the carbonation reaction to convert CO(2) to CaCO(3). The maximum CO(2) sequestration potential was achieved with immobilized CA (480 mg CaCO(3)/mg protein). These properties suggest that immobilized VSG-4 carbonic anhydrase has the potential to be used for biomimetic CO(2) sequestration.

Development and feasibility study of a sensory-enhanced robot-aided motor training in stroke rehabilitation

Functional impairment of the upper limb is a major challenge faced by many stroke survivors. The present study aimed at developing a novel sensory-enhanced robot-aided motor training program and testing its feasibility in stroke rehabilitation. A specially designed robot handle was developed as an attachment to the Inmotion2 robotic system. This handle provided sensory stimulation through pins connected to small servo motors inside the handle. Vibration of the pins was activated during motor training once pressure on the handle reached a certain threshold indicating an active motion of the study subject. Nine chronic stroke survivors were randomly assigned to either a sensory-enhanced robot-aided motor training group (SERMT) or robot-aided motor training only group (RMT). All participants underwent a 6-week motor training program, performing target reaching movements with the specialized handle with or without vibration stimulation during training. Motor Status (MS) scores were measured for functional outcome prior to and after training. The results showed significant improvement in the total MS scores after training in both experimental groups. However, MS sub-scores for the shoulder/elbow and the wrist/hand increased significantly only in the SERMT group (p<0.05). Future studies are required to confirm these preliminary findings.

Positive antibacterial co-action between hop (Humulus lupulus) constituents and selected antibiotics

The research reported here deals with co-action of the hop (Humulus lupulus)-derived anti-bacterial compounds, lupulone and xanthohumol, with several antibiotics. Among the antibiotics investigated for their co-action, polymyxin B sulfate, tobramycin and ciprofloxacin had a positive co-action in inhibiting selected test bacteria. The disc/well-diffusion assay and the minimum inhibitory concentration test (MIC) were employed to determine co-action. Both Gram-positive and Gram-negative bacteria were used in the evaluation. There was some co-action against all Gram-positive bacteria tested. Surprisingly, there was some positive co-action even against certain Gram-negative bacteria but not against others. Particularly, there was no co-action against E.coli. An antibacterial cream with lupulone, neomycin and polymyxin B sulfate was prepared and showed co-action. Ideas for other practical applications of this effect are put forth. The mechanism of the synergistic effect is briefly discussed but no attempt was made to prove it experimentally.

Rosai–Dorfman disease of the central nervous system

Rosai-Dorfman disease (RDD) is an idiopathic, non-neoplastic, lymphoproliferative disorder characterized by sinus histiocytosis and massive lymphadenopathy. When RDD involves the central nervous system the lesion simulates a meningioma. Histological and immunohistochemical confirmation is essential for a definitive diagnosis. In this paper, ten cases of RDD confined to the central nervous system are reported. Another case with orbital RDD was excluded. Nine cases involved the cranial cavity alone; in one, the cervical extradural region was also involved. Treatment consisted of surgical excision or biopsy. Histology and immunohistochemistry revealed a mixed cell population of predominantly mature histiocytes with evidence of emperipolesis and strong positivity for S100 protein in all cases. No recurrence was observed during follow up ranging from three months to eight years.