Inflammatory Biomarkers and Physiomarkers of Late-Onset Sepsis and Necrotizing Enterocolitis in Premature Infants

Background

Early diagnosis of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) in VLBW (<1500g) infants is challenging due to non-specific clinical signs. Inflammatory biomarkers increase in response to infection, but non-infectious conditions also cause inflammation in premature infants. Physiomarkers of sepsis exist in cardiorespiratory data and may be useful in combination with biomarkers for early diagnosis.

Objectives

To determine whether inflammatory biomarkers at LOS or NEC diagnosis differ from times without infection, and whether biomarkers correlate with a cardiorespiratory physiomarker score.

Methods

We collected remnant plasma samples and clinical data from VLBW infants. Sample collection occurred with blood draws for routine laboratory testing and blood draws for suspected sepsis. We analyzed 11 inflammatory biomarkers and a continuous cardiorespiratory monitoring (POWS) score. We compared biomarkers at gram-negative (GN) bacteremia or NEC, gram-positive (GP) bacteremia, negative blood cultures, and routine samples.

Results

We analyzed 188 samples in 54 VLBW infants. Biomarker levels varied widely, even at routine laboratory testing. Several biomarkers were increased at the time of GN LOS or NEC diagnosis compared with all other samples. POWS was higher in patients with LOS and correlated with five biomarkers. IL-6 had 78% specificity at 100% sensitivity to detect GN LOS or NEC and added information to POWS (AUC POWS = 0.610, POWS + IL-6 = 0.680).

Conclusions

Inflammatory biomarkers discriminate sepsis due to GN bacteremia or NEC and correlate with cardiorespiratory physiomarkers. Baseline biomarkers did not differ from times of GP bacteremia diagnosis or negative blood cultures.

Intranasal delivery of a synthetic Entamoeba histolytica vaccine containing adjuvant (LecA + GLA-3M-052 liposomes): in vitro characterization

Amebiasis, a disease caused by the parasite Entamoeba histolytica, is estimated to cause millions of infections and at least 55,000 deaths globally each year. With no vaccine currently available, there is an urgent need for an accessible means of stimulating protective mucosal immunity. The objective of this study was to characterize the nasal spray of a novel amebiasis vaccine candidate from a syringe-based liquid atomization device, the Teleflex MAD Nasal™, in both adult and infant nasal airways. Human ergonomic testing was completed to determine realistic actuation parameters. Spray pattern, plume geometry, and droplet size distribution were measured to evaluate reproducibility of free plume characteristics. The Alberta Idealized Nasal Inlet (AINI) and three realistic infant nasal airways were used to determine the in vitro deposition profile in adult and infant airways, respectively. Collectively, in vitro results demonstrated the feasibility of delivering the vaccine candidate to target sites within the nasal airways. Penetration through the nasal airways that could lead to deposition in the lungs was below the limit of quantification for both adult and infant geometries, indicating a low likelihood of adverse events due to lung exposure. These results support continued investigation of intranasal delivery of the synthetic Entamoeba histolytica vaccine.

Blood pressure variability in hypertension patients in Indian clinical settings

Funding Acknowledgements

Type of funding sources: None.

Background

 Blood pressure variability (BPV) is a potential predictor for complications such as coronary artery disease, heart failure, stroke, and all-cause death, independently of mean blood pressure (BP) in patients with hypertension.(1)

Objective

 The survey was carried out to seek the opinion of Indian clinicians on the burden, measurement  and management of BPV in patients with hypertension.

Method

 This PAN-India survey used a structured web-based objective questionnaire that was administered to 200 clinicians via google forms. The responses were analyzed descriptively.

Results

 This study suggests that &gt;80% of the clinicians reported that 10-40% of their hypertensive patients experience BPV while 13% and 6.5% respectively, reported having BPV issues in &lt;10% and &gt;40% of their patients.

A large majority of the clinicians (88.5%) agreed that effective control of BPV in hypertensive patients exerts benefits to prevent complications like target organ damage, cardiovascular disease and mortality.

A combination of home and office BP monitoring was the most recommended approach for the measurement of BPV by 28% of the clinicians, followed by home monitoring (23%) &gt; ambulatory monitoring (22.5%) &gt; combination of ambulatory and office monitoring (21%) &gt; office monitoring (4.5%) of BP. A majority of clinicians opted for angiotensin receptor blocker (ARB) + calcium channel blocker (CCB), ARB + beta blocker (BB) and ARB + diuretic as most preferred antihypertensive combination for effective control of BP and BPV (Figure 1). In particular, the clinicians opined for Telmisartan + Amlodipine (45.5%) &gt; Telmisartan + Chorthalidone (27%) &gt; Telmisartan + Cilnidipine (14%) &gt; Telmisartan + Hydrochlorothiazide (13%) as the preferred antihypertensive combinations.

41% and 30.5% of the clinicians reported that they would shift their patients with high BPV to a dual and a triple combination of antihypertensives, respectively followed by increasing the antihypertensive dose (18%) and shifting to new antihypertensive medication (8.5%).

Conclusion

 The survey underlined the considerable prevalence of BPV in hypertensive individuals and that its control can be beneficial in reducing the risk of future complications. The study also reflects that both home and office BP monitoring are important to identify BPV while ARBs particularly, Telmisartan in combination with CCB or a diuretic is the preferred regimen for effective control of BP and BPV. Abstract Figure 1

An indian clinician outlook on hypertension care during Covid-19 pandemic

Funding Acknowledgements

Type of funding sources: None.

Background

Hypertension (HTN) has been found to increase the risk of Covid-19 mortality when compared with normotensives, and those discontinuing the antihypertensive treatment have an additional fatality risk.

Objective

The survey was carried out to seek the opinion of Indian healthcare practitioners (HCPs) on the risk factors, challenges and management of HTN during the ongoing Covid-19 pandemic.

Method

This was a structured web-based objective questionnaire survey involving 2545 HCPs PAN-India. The survey comprised questions related to the risk factors for HTN, home blood pressure monitoring (HBPM), BP control, treatment, complications and challenges of uncontrolled HTN during Covid-19.

Results

This study showed that tobacco use, obesity and comorbidities are top three modifiable risk factors for HTN followed by emotional stress, during Covid-19 pandemic. A majority of HCPs (44%) reported that <30% of their hypertensive patients check BP at home while 36% and 20% reported that 30-50% and >50% of their patients respectively, practice HBPM. 20%, 63%, and 17% of HCPs respectively, reported that <20%, 20-40% and >40% of their patients presented with BP > 150/100 mmHg during lockdown. Of all the HCPs, 53% and 33% respectively, reported BP increase in <20% and 20-40% of their patients on monotherapy while 14% of HCPs reported BP increase in >40% of their patients on monotherapy during the lockdown. As compared to high dose monotherapy, dual and triple combination therapies (TDC) were selected as most preferred for the management of uncontrolled BP opted by 56% and 34% of the HCPs, respectively. The dual combination antihypertensives were ranked as angiotensin receptor blockers (ARB) + diuretic (DU) > ARB + calcium channel blockers (CCB) > ARB + beta-blocker. The TDC with ARB + CCB + DU was the most favored TDC antihypertensive therapy during Covid-19 era. Acute coronary syndrome was anticipated as the most common complication of HTN in the Covid-19 pandemic, followed by renal dysfunction, cerebral ischemia and cerebral hemorrhage reported by 47%, 17%, 14% and 14% of HCPs, respectively. Multiple challenges in HTN care during Covid-19 as opined by HCPs included BP measurement while avoiding the risk of infection (57%), advising treatment via teleconsultation (48%), dose modification (41%), patient compliance (32%) and transport-related issues (30%). Most of the HCPs believed that self-monitoring of BP (32%) and economical medicines (24%) can improve medication adherence in patients with HTN.

Conclusion

The study underlined that the provision of economic medicines, single pill combinations, doctor-patient digital connect, and patient education can help in improving medication adherence leading to better outcomes in patients with HTN during Covid-19.  The study also suggested the need to enhance HBPM and the use of ARB-based dual and triple combination therapies to improve BP control in patients uncontrolled on monotherapy during Covid-19 pandemic.

Rapid detection of Clostridium difficile via magnetic bead aggregation in cost-effective polyester microdevices with cell phone image analysis

A centrifugally-driven polyester microdevice for sequence-specific detection ofClostridium difficileusing magnetic beads, isothermal amplification, and cell phone image analysis.

Expression, purification, and evaluation of recombinant LecA as a candidate for an amebic colitis vaccine

Entamoeba histolytica, which causes amebic colitis and liver abscess, is considered a major enteric pathogen in residents and travelers to developing countries where the disease is endemic. Interaction of this protozoan parasite with the intestine is mediated through the binding of the trophozoite stage to intestinal mucin and epithelium via a galactose and N-acetyl-d-galactosamine (Gal/GalNAc) lectin comprised of a disulfide linked heavy (ca. 180 kDa) and light chain (ca. 35 kDa) and a noncovalently bound intermediate subunit (ca. 150 kDa). Our efforts to develop a vaccine against this pathogen have focused on an internal 578 amino acid fragment, designated LecA, located within the cysteine-rich region of the heavy chain subunit because: (i) it is a major target of adherence-blocking antibodies of seropositive individuals and (ii) vaccination with his-tagged LecA provides protection in animal models. We developed a purification process for preparing highly purified non-tagged LecA using a codon-optimized gene expressed in Escherichia coli. The process consisted of: (i) cell lysis, collection and washing of inclusion bodies; (ii) solubilization and refolding of denatured LecA; and (iii) a polishing gel filtration step. The purified fragment existed primarily as a random coil with β-sheet structure, contained low endotoxin and nucleic acid, was highly immunoreactive, and elicited antibodies that recognized native lectin and that inhibited in vitro adherence of trophozoites to CHO cells. Immunization of CBA mice with LecA resulted in significant protection against cecal colitis. Our procedure yields sufficient amounts of highly purified LecA for future studies on stability, immunogenicity, and protection with protein-adjuvant formulations.

Replication initiation at a distance: determination of the cis- and trans-acting elements of replication origin alpha of plasmid R6K

Plasmid R6K, which contains 3 replication origins called alpha, gamma, and beta, is a favorable system to investigate the molecular mechanism(s) of action at a distance, i.e. replication initiation at a considerable distance from the primary initiator protein binding sites (iterons). The centrally located gamma origin contains 7 iterons that bind to the plasmid-encoded initiator protein, pi. Ori alpha, located at a distance of approximately 4 kb from gamma, contains a single iteron that does not directly bind to pi but is believed to access the protein by pi-mediated alpha-gamma iteron-iteron interaction that loops out the intervening approximately 3.7 kb of DNA. Although the cis-acting components and the trans-acting proteins required for ori gamma function have been analyzed in detail, such information was lacking for ori alpha. Here, we have identified both the sequence elements located at alpha and those at gamma, that together promoted alpha activity. The data support the conclusion that besides the single iteron, a neighboring DNA primase recognition element called G site is essential for alpha-directed plasmid maintenance. Sequences preceding the iteron and immediately following the G site, although not absolutely necessary, appear to play a role in efficient plasmid maintenance. In addition, while both dnaA1 and dnaA2 boxes that bind to DnaA protein and are located at gamma were essential for alpha activity, only dnaA2 was required for initiation at gamma. Mutations in the AT-rich region of gamma also abolished alpha function. These results are consistent with the interpretation that a protein-DNA complex consisting of pi and DnaA forms at gamma and activates alpha at a distance by DNA looping.