High-intensity interval training in cardiac rehabilitation (HIIT or MISS UK): A multi-centre randomised controlled trial

BACKGROUND

There is a lack of international consensus regarding the prescription of high-intensity interval exercise training (HIIT) for people with coronary artery disease (CAD) attending cardiac rehabilitation (CR).

AIM

To assess the clinical effectiveness and safety of low-volume HIIT compared with moderate intensity steady-state (MISS) exercise training for people with CAD.

METHODS

We conducted a multi-centre RCT, recruiting 382 patients from 6 outpatient CR centres. Participants were randomised to twice-weekly HIIT (n = 187) or MISS (n = 195) for 8 weeks. HIIT consisted of 10 × 1-minute intervals of vigorous exercise (>85% maximum capacity) interspersed with 1-minute periods of recovery. MISS was 20-40 minutes of moderate intensity continuous exercise (60-80% maximum capacity). The primary outcome was the change in cardiorespiratory fitness (peak oxygen uptake, VO2 peak) at 8-week follow-up. Secondary outcomes included cardiovascular disease risk markers, cardiac structure and function, adverse events, and health-related quality of life.

RESULTS

At 8 weeks, VO2  peak improved more with HIIT (2.37 mL.kg-1.min-1; SD, 3.11) compared with MISS (1.32 mL.kg-1.min-1; SD, 2.66). After adjusting for age, sex and study site, the difference between arms was 1.04 mL.kg-1.min-1 (95% CI, 0.38 to 1.69; p = 0.002). Only 1 serious adverse event was possibly related to HIIT.

CONCLUSIONS

In stable CAD, low-volume HIIT improved cardiorespiratory fitness more than MISS by a clinically meaningful margin. Low-volume HIIT is a safe, well tolerated, and clinically effective intervention that produces short-term improvement in cardiorespiratory fitness. It should be considered by all CR programmes as an adjunct or alternative to MISS.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02784873. https://clinicaltrials.gov/ct2/show/NCT02784873.

Heart failure with preserved ejection fraction (HFpEF) pathophysiology study (IDENTIFY-HF): rise in arterial stiffness associates with HFpEF with increase in comorbidities

Background

There has been a shift in paradigm proposing that comorbidities play a significant role towards the pathophysiology of the heart failure with preserved ejection fraction (HFpEF) syndrome. Further, HFpEF patients have abnormal macrovascular function, potentially contributing significantly in altered ventricular-vascular coupling in these patients. However, our full understanding of the role of comorbidities, arterial stiffness and it relationship with HFpEF remains incomplete.

Purpose

The IDENTIFY-HF study aims to shed light on the HFpEF pathophysiology and investigates whether gradually increase in arterial stiffness (in addition to ageing) due to increasing common comorbidities, such as hypertension and diabetes, is associated with HFpEF.

Methods

Arterial compliance was assessed in five groups (Groups A to E) matched for age, (≥70 years), sex and renal function: Group A; normal healthy volunteers without major comorbidities (control). Group B; patients with hypertension only. Group C; patients with hypertension and diabetes mellitus only. Group D; patients with HFpEF. Group E; patients with heart failure and reduced ejection fraction (HFrEF); the parallel group. Arterial compliance was assessed using pulse wave velocity (PWV), as the primary outcome measure and was compared between Group A to D. A separate comparison was made between Groups D and E. To avoid confounding factors, participants were asked to omit their morning blood pressure medication and abstain from caffeine for 12 hours prior to the study.

Results

From the 95 volunteers recruited, PWV was obtained in 94 subjects. The mean PWV in group A, B, C, D and E was 10.2-, 12.2-, 13.0-, 13.7- and 10.0 m/s respectively. After adjusting for covariance (age, sex, BMI and renal function), the mean difference between Group A (healthy volunteers) and D (HFpEF) was 2.14 m/s (p=0.023). Whilst the mean difference between the HFpEF and HFrEF group D and E respectively was 2.68 m/s (p=0.003).

Conclusion

Rise in comorbidities increases arterial stiffness, as measured by pulse wave velocity, which in turn significantly associates with HFpEF (p=0.023). It is therefore possible that the HFpEF syndrome may not be due to a primary cardiac pathology but rather an end-result of non-cardiac comorbidities affecting vascular resistance with perhaps some secondary cardiac involvement.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): 1)West Midlands Clinical Research Network, National Institute of Health Research, UK2)Research, Development & Innovation department of the University Hospitals Coventry & Warwickshire NHS Trust (RDI, UHCW), UK.

Real-world evaluation of follow up strategies after implantable cardiac-defibrillator therapies in patients with ventricular tachycardia (REFINE-VT)

Introduction

Implantable cardiac-defibrillators (ICD) can prevent sudden cardiac death but the risk of recurrent ventricular arrhythmia (VA) and ICD therapies persists. Established strategies to minimize such risks include medication optimization, device reprogramming or ventricular tachycardia (VT) catheter ablation (CA). However, the timing and choice of these strategies at ICD follow-up may not be as consistent in the real-world as the regulated conditions of clinical trials. Furthermore, whether these decisions at follow-up are influenced by the type of arrhythmia, ICD therapy or patient characteristics remain unclear.

Purpose

We evaluated ICD follow-up strategies in patients with ischaemic (ICM) and non-ischaemic cardiomyopathy (NICM) to refine the outpatient management of these complex patients and ultimately improve overall patient outcome.

Methods

REFINE-VT is a retrospective study of 514 patients with ICD/CRT-D who attended ICD follow-up between June 2018 to September 2019 at the University Hospital Coventry & Warwickshire (UHCW) tertiary cardiology department. All follow-ups were face-to-face. Patients were divided into 2 groups according to the absence or presence of sustained VA (e.g. >30 seconds of VT and/or appropriate ICD therapy), described as “negative event” and “positive event” groups respectively. The type of strategy employed in response to a positive event were categorized into 4 groups: (1) Medication change only (2) Device programming +/− medication (3) Referral for VT CA (4) No intervention

Results

514 consecutive patients with ICD (52%) or CRT-D (48%) were analysed. Overall mean age was 67±14 years with 79% male patients. ICM was diagnosed in 329 (64%) patient and NICM in 185 (36%). 437 (85%) patients had no significant VA and/or ICD therapy referred to as the negative group. A total of 77 patients (15%) suffered VA and/or ICD therapies, of whom 22 patients (26%) experienced a second event. 31% (n=24) of this positive event group received no preventative strategy (Table 1). We observed an inconsistent approach to the choice of strategies across different types of arrhythmias and ICD therapies. E.g. the odds of intervening were significantly higher if ICD shock was detected compared to anti-tachycardia pacing (OR 8.4, 95% CI 1.7–39.6, p=0.007). Even in patients with two events, the rate of referral for VT ablation and escalation of antiarrhythmics were similarly as low as patients with a single event (Table 2).

Conclusion

This is the first contemporary study that has evaluated how strategies that reduce the risk of recurrent ICD events are executed in a real-world population. We have demonstrated that the decision to intervene and choices of strategy remain inconsistent and partially biased by the type of arrhythmia and ICD therapy at follow-up. This supports the need for an evidence-driven multi-disciplinary VT clinic to refine and standardize our approach to this heterogeneous population.

Funding Acknowledgement

Type of funding sources: None.

HEMOPHAGOCYTOSIS SECONDARY TO PHARYNGEAL ABSCESS IN AN IMMUNOCOMPETENT PATIENT (case report)

Background. Hemophagocytosis is a rare, potentially fatal disorder, comprising pancytopenia, liver dysfunction, hepatosplenomegaly, hypertriglyceridemia, and hyperferritinemia presenting as fever, lympha­denopathy and skin rashes. Objective. To attract the clinicians’ attention to a problem of hemophagocytosis in Critical Care management.Methods. Hemophagocytosis secondary to pharyngeal abscess in a 58 year old male is being reported.Results. A 58-year-old immunocompetent patient presenting with hemophagocytosis secondary to pharyngeal abscess, was managed on ventilator and inotropic support, when he developed heathcare-associated urinary tract infection by Escherichia coli and ventilator-associated pneumonia by Acinetobacter baumanii. He developed neutropenic septic shock and multi-organ dysfunction and went through a downhill course leading to demise.Conclusions. Hemophagocytosis remains a sinister entity in modern intensive care despite astute clinical management. Secondary superinfections with opportunistic multidrug resistant pathogens are difficult to treat. A high index of clinical suspicion, aggressive diagnosis and prompt treatment for hemophagocytosis and polymicrobial opportunistic superinfections with multidrug-resistant healthcare-associated pathogens needs to be addressed upfront.

Effect of chronic kidney disease on serum resistin level

BACKGROUND

Chronic Kidney Diseases (CKD) of all etiologies are usually associated with Insulin Resistance (IR). Resistin is also a protein associated with IR. Some studies conducted abroad have shown that resistin level is higher among CKD patients.

OBJECTIVE

To test if serum resistin level is significantly higher in CKD patients compared to normal individuals.

PATIENTS AND METHODS

96 CKD patients and 97 normal individuals were included in the study. Written informed consent was obtained from every individual.

RESULTS

Serum resistin level was higher in CKD patients compared to control subjects. The difference in serum resistin level between two groups was statistically significant.

CONCLUSION

Our study is probably the first study in India comparing serum resistin levels of CKD patients vis-à-vis control subjects. Further cellular research may be needed to explore this relation.

Colossal dielectric permittivity in Co-doped ZnO ceramics prepared by a pressure-less sintering method

Dielectric properties and impedance spectroscopic studies of single phase Zn_1−xCo_xO (0 ≤ x ≤ 0.05) ceramics, synthesized by a pressure-less solid state reaction method, have been carried out to investigate the origin of colossal dielectric permittivity (CP), ε′ ∼ 10⁵, in a wide frequency (2 × 10¹–2 × 10⁶ Hz) range.

Cord blood NK cells engineered to express IL-15 and a CD19-targeted CAR show long-term persistence and potent antitumor activity

Chimeric antigen receptors (CARs) have been used to redirect the specificity of autologous T cells against leukemia and lymphoma with promising clinical results. Extending this approach to allogeneic T cells is problematic as they carry a significant risk of graft-versus-host disease (GVHD). Natural killer (NK) cells are highly cytotoxic effectors, killing their targets in a non-antigen-specific manner without causing GVHD. Cord blood (CB) offers an attractive, allogeneic, off-the-self source of NK cells for immunotherapy. We transduced CB-derived NK cells with a retroviral vector incorporating the genes for CAR-CD19, IL-15 and inducible caspase-9-based suicide gene (iC9), and demonstrated efficient killing of CD19-expressing cell lines and primary leukemia cells in vitro, with marked prolongation of survival in a xenograft Raji lymphoma murine model. Interleukin-15 (IL-15) production by the transduced CB-NK cells critically improved their function. Moreover, iC9/CAR.19/IL-15 CB-NK cells were readily eliminated upon pharmacologic activation of the iC9 suicide gene. In conclusion, we have developed a novel approach to immunotherapy using engineered CB-derived NK cells, which are easy to produce, exhibit striking efficacy and incorporate safety measures to limit toxicity. This approach should greatly improve the logistics of delivering this therapy to large numbers of patients, a major limitation to current CAR-T-cell therapies.

Structural and functional diversity of nonapeptide hormones from an evolutionary perspective: A review

The article presents an overview of the comparative distribution, structure and functions of the nonapeptide hormones in chordates and non chordates. The review begins with a historical preview of the advent of the concept of neurosecretion and birth of neuroendocrine science, pioneered by the works of E. Scharrer and W. Bargmann. The sections which follow discuss different vertebrate nonapeptides, their distribution, comparison, precursor gene structures and processing, highlighting the major differences in these aspects amidst the conserved features across vertebrates. The vast literature on the anatomical characteristics of the nonapeptide secreting nuclei in the brain and their projections was briefly reviewed in a comparative framework. Recent knowledge on the nonapeptide hormone receptors and their intracellular signaling pathways is discussed and few grey areas which require deeper studies are identified. The sections on the functions and regulation of nonapeptides summarize the huge and ever increasing literature that is available in these areas. The nonapeptides emerge as key homeostatic molecules with complex regulation and several synergistic partners. Lastly, an update of the nonapeptides in non chordates with respect to distribution, site of synthesis, functions and receptors, dealt separately for each phylum, is presented. The non chordate nonapeptides share many similarities with their counterparts in vertebrates, pointing the system to have an ancient origin and to be an important substrate for changes during adaptive evolution. The article concludes projecting the nonapeptides as one of the very first common molecules of the primitive nervous and endocrine systems, which have been retained to maintain homeostatic functions in metazoans; some of which are conserved across the animal kingdom and some are specialized in a group/lineage-specific manner.

Submandibular intubation in awake patient of panfacial trauma

Maxillofacial trauma patients present with airway problems. Submandibular intubation is an effective means of intubation to avoid tracheostomy for operative procedures. Airway is secured with oral endotracheal intubation in paralyzed patient and tube is then transplaced in sub mental or submandibular region. However there may be instances when paralyzing such trauma patients is not safe and short term tracheostomy is the only airway channel available for conduction of anesthesia. We report a case of submandibular intubation in awake patient of maxillofacial trauma with anticipated intubation problems.

A dynamic landscape of allergen associations in delayed-type cutaneous hypersensitivity

BACKGROUND

Delayed-type hypersensitivity represents a significant clinical and public health challenge. Patients undergoing patch testing may exhibit positive reactions to more than one allergen. It is recognized that reactions to specific pairs of allergens are associated, reflecting a combination of exposure patterns and structural similarity.

OBJECTIVES

To explore the influence of time of testing, age, sex and atopy status on allergen pair associations in a series of 45 110 consecutive patients tested over 30 years.

METHODS

Patch test records of all patients undergoing testing with a modified European baseline series between 1985 and 2014 were retrieved from a database at St John's Institute of Dermatology. Reactions were read on days 2 and 4. For each allergen it was recorded whether the allergen was tested and whether the result was positive or negative.

RESULTS

This is the largest reported study of patch test allergen pair relationships. Our analysis shows a high degree of variability in allergen pair associations. Rigorous statistical analysis reveals a large number of differences between groups, including a significant increase in the association between formaldehyde and multiple formaldehyde-releasing preservatives over the study period, in addition to pair associations with cobalt and formaldehyde-releasing preservatives. These were present to a significantly greater extent in men than in women.

CONCLUSIONS

These observations extend our understanding of cutaneous allergy, with implications for both clinical practice and mechanisms of cutaneous hypersensitivity.

Balancing functions of annexin A6 maintain equilibrium between hypertrophy and apoptosis in cardiomyocytes

Pathological cardiac hypertrophy is a major risk factor associated with heart failure, a state concomitant with increased cell death. However, the mechanism governing progression of hypertrophy to apoptosis at the single-cell level remains elusive. Here, we demonstrate annexin A6 (Anxa6), a calcium (Ca(2+))-dependent phospholipid-binding protein critically regulates the transition of chronic hypertrophied cardiomyocytes to apoptosis. Treatment of the H9c2(2-1) cardiomyocytes with hypertrophic agonists upregulates and relocalizes Anxa6 with increased cytosolic punctate appearance. Live cell imaging revealed that chronic exposure to hypertrophic agonists such as phenylephrine (PE) compromises the mitochondrial membrane potential (ΔΨm) and morphological dynamics. Such chronic hypertrophic induction also activated the caspases 9 and 3 and induced cleavage of the poly-(ADP-ribose) polymerase 1 (Parp1), which are the typical downstream events in the mitochondrial pathways of apoptosis. An increased rate of apoptosis was evident in the hypertrophied cardiomyocytes after 48-72 h of treatment with the hypertrophic agonists. Anxa6 was progressively associated with the mitochondrial fraction under chronic hypertrophic stimulation, and Anxa6 knockdown severely abrogated mitochondrial network and dynamics. Ectopically expressed Anxa6 protected the mitochondrial morphology and dynamics under PE treatment, and also increased the cellular susceptibility to apoptosis. Biochemical analysis showed that Anxa6 interacts with Parp1 and its 89 kDa cleaved product in a Ca(2+)-dependent manner through the N-terminal residues (1-28). Furthermore, expression of Anxa6(S13E), a mutant dominant negative with respect to Parp1 binding, served as an enhancer of mitochondrial dynamics, even under chronic PE treatment. Chemical inhibition of Parp1 activity released the cellular vulnerability to apoptosis in Anxa6-expressing stable cell lines, thereby shifting the equilibrium away from cell death. Taken together, the present study depicts a dual regulatory function of Anxa6 that is crucial for balancing hypertrophy with apoptosis in cardiomyocytes.

Ascites alone as the presentation of Congenital Tuberculosis

Congenital tuberculosis is a rare disease. It usually presents with respiratory distress, fever and organomegaly. We report a case of congenital tuberculosis presenting with ascites only.DOI: http://dx.doi.org/10.3126/jcmsn.v10i1.12766 Journal of College of Medical Sciences-Nepal, 2014, Vol.10(1); 37-40

Uncoupling Neogenin association with lipid rafts promotes neuronal survival and functional recovery after stroke

The dependence receptor Neogenin and its ligand, the repulsive guidance molecule a (RGMa), regulate apoptosis and axonal growth in the developing and the adult central nervous system (CNS). Here, we show that this pathway has also a critical role in neuronal death following stroke, and that providing RGMa to neurons blocks Neogenin-induced death. Interestingly, the Neogenin pro-death function following ischemic insult depends on Neogenin association with lipid rafts. Thus, a peptide that prevents Neogenin association with lipid rafts increased neuronal survival in several in vitro stroke models. In rats, a pro-survival effect was also observed in a model of ocular ischemia, as well as after middle cerebral artery occlusion (MCAO). Treatments that prevented Neogenin association with lipid rafts improved neuronal survival and the complexity of the neuronal network following occlusion of the middle artery. Toward the development of a treatment for stroke, we developed a human anti-RGMa antibody that also prevents Neogenin association with lipid rafts. We show that this antibody also protected CNS tissue from ischemic damage and that its application resulted in a significant functional improvement even when administrated 6 h after artery occlusion. Thus, our results draw attention to the role of Neogenin and lipid rafts as potential targets following stroke.

Immune-driven adaptation of hepatitis B virus genotype D involves preferential alteration in B-cell epitopes and replicative attenuation--an insight from human immunodeficiency virus/hepatitis B virus coinfection

An important driving force behind the sequence diversity of hepatitis B virus (HBV) is viral adaptation to host immune responses. To gain an insight into the impact of host immunity on genetic diversification and properties of HBV, we characterized HBV of genotype D from treatment-naive hepatitis B e antigen-positive (EP) and hepatitis B e antigen-negative (EN) patients with chronic hepatitis B (CHB), where HBV is under stronger immune pressure, with that of HBV derived from human immunodeficiency virus (HIV)/HBV-coinfected individuals, where HIV infection has significantly weakened the immune system. Full-length sequence analysis showed that HBV heterogeneity was most extensive in EN-CHB followed by EP-CHB and HIV/HBV coinfection. The relative magnitude of non-synonymous changes within B-cell epitopes was greater than that in T-cell epitopes of HBV open reading frames (ORFs) in both EP-CHB and EN-CHB. Nine amino acid substitutions were identified in B-cell epitopes and one in a T-cell epitope of HBV in EN-CHB, most of which resulted in altered hydrophobicities, as determined using the Kyte and Doolittle method, relative to wild-type residues found in HBV from the HIV-positive group. Additionally, 19 substitutions occurred at significantly higher frequencies in non-epitope regions of HBV ORF-P in EN-CHB than HIV/HBV-coinfected patients. In vitro replication assay demonstrated that the substitutions, particularly in reverse transcriptase and RNaseH domains of ORF-P, resulted in a decline in replication capacity of HBV. Hence, our results indicate that HBV adapts to increasing immune pressure through preferential mutations in B-cell epitopes and by replicative attenuation. The viral epitopes linked to immune response identified in this study bear important implications for future HBV vaccine studies.

Comparative anti-proliferative activity of some new 2-(arylazo)phenolate-palladium (II) complexes and cisplatin against some human cancer cell lines

In this study, we report the synthesis of four 2-(arylazo)phenol-Pd(II) complexes and their anti-proliferative property against the human lung cancer (A549), cervical cancer (HeLa), and ovarian teratocarcinoma (PA-1) cell lines with cisplatin as the gold standard. One of the complexes, [Pd(L(2))2], induced robust apoptosis in all the chosen cells, as revealed by annexin-V-positive/propidium iodide dual staining, increased sub-G1 cell cycle population, and significant morphological changes in the treated cells. The Pd complex inflicted mitochondrial dysfunction leading to mitochondrial membrane potential loss, reactive oxygen species generation and release of cytosolic cytochrome c that activated caspase-9 and caspase-3 proteins which finally caused programmed cell death.