Novel Human Parechovirus 3 Diversity, Recombination, and Clinical Impact Across 7 Years: An Australian Story

BACKGROUND

A novel human parechovirus 3 Australian recombinant (HPeV3-AR) strain emerged in 2013 and coincided with biennial outbreaks of sepsis-like illnesses in infants. We evaluated the molecular evolution of the HPeV3-AR strain and its association with severe HPeV infections.

METHODS

HPeV3-positive samples collected from hospitalized infants aged 5-252 days in 2 Australian states (2013-2020) and from a community-based birth cohort (2010-2014) were sequenced. Coding regions were used to conduct phylogenetic and evolutionary analyses. A recombinant-specific polymerase chain reaction was designed and utilized to screen all clinical and community HPeV3-positive samples.

RESULTS

Complete coding regions of 54 cases were obtained, which showed the HPeV3-AR strain progressively evolving, particularly in the 3' end of the nonstructural genes. The HPeV3-AR strain was not detected in the community birth cohort until the initial outbreak in late 2013. High-throughput screening showed that most (>75%) hospitalized HPeV3 cases involved the AR strain in the first 3 clinical outbreaks, with declining prevalence in the 2019-2020 season. The AR strain was not statistically associated with increased clinical severity among hospitalized infants.

CONCLUSIONS

HPeV3-AR was the dominant strain during the study period. Increased hospital admissions may have been from a temporary fitness advantage and/or increased virulence.

Testing the Electronic Personal Health Record Acceptance Model by Nurses for Managing Their Own Health: A Cross-sectional Survey

BACKGROUND

To our knowledge, no evidence is available on health care professionals' use of electronic personal health records (ePHRs) for their health management. We therefore focused on nurses' personal use of ePHRs using a modified technology acceptance model.

OBJECTIVES

To examine (1) the psychometric properties of the ePHR acceptance model, (2) the associations of perceived usefulness, ease of use, data privacy and security protection, and perception of self as health-promoting role models to nurses' own ePHR use, and (3) the moderating influences of age, chronic illness and medication use, and providers' use of electronic health record (EHRs) on the associations between the ePHR acceptance constructs and ePHR use.

METHODS

A convenience sample of registered nurses, those working in one of 12 hospitals in the Maryland and Washington, DC areas and members of the nursing informatics community (AMIA and HIMSS), were invited to respond to an anonymous online survey; 847 responded. Multiple logistic regression identified associations between the model constructs and ePHR use, and the moderating effect.

RESULTS

Overall, ePHRs were used by 47%. Sufficient reliability for all scales was found. Three constructs were significantly related to nurses' own ePHR use after adjusting for covariates: usefulness, data privacy and security protection, and health-promoting role model. Nurses with providers that used EHRs who perceived a higher level of data privacy and security protection had greater odds of ePHR use than those whose providers did not use EHRs. Older nurses with a higher self-perception as health-promoting role models had greater odds of ePHR use than younger nurses.

CONCLUSIONS

Nurses who use ePHRs for their personal health might promote adoption by the general public by serving as health-promoting role models. They can contribute to improvements in patient education and ePHR design, and serve as crucial resources when working with their individual patients.

Guidelines for the treatment of myelodysplastic syndromes (MDS) in South Africa

INTRODUCTION

Myelodysplastic syndromes (MDS) encompass a heterogeneous group of clonal haematopoietic disorders characterised by chronic and progressive cytopenias resulting from ineffective haematopoiesis. Treatment is complicated by differences in disease mechanisms in different subgroups, variable clinical phenotypes and risk of progression to acute myeloid leukaemia.

RATIONALE

Changes in disease classification, prognostic scoring systems, the availability of novel treatment options and the absence of South African guidelines for the diagnosis and management of these complex disorders underpinned the need for the development of these recommendations.

METHODS

These recommendations are based on the opinion of a number of experts in the field from the laboratory as well as clinical settings and came from both the private and institutional academic environments. The most recent literature as well as available guidelines from other countries were discussed and debated at a number of different meetings held over a 2-year period.

RESULTS

A comprehensive set of recommendations was developed focusing on risk stratification, supportive management and specific treatment. Novel agents and their indications are discussed and recommendations are made based on best available evidence and taking into account the availability of treatments in South Africa.

CONCLUSION

Correct diagnosis, risk stratification and appropriate therapeutic choices are the cornerstones of success in the management of patients with myelodysplastic syndromes.

Modulation of nutrient sensing nuclear hormone receptors promotes weight loss through appetite suppression in mice

AIM

Peroxisome proliferator activated receptors (PPARs) are nuclear receptors involved in glucose and lipid metabolism. Three isoforms of PPARs have been identified with different tissue distribution and biological functions. Although the pharmacology of each receptor is well studied, the physiological effect of simultaneous activation of PPARalpha, gamma and delta is only starting to emerge. We sought to determine the biological effects of a novel PPAR pan activator and elucidate the physiological mechanisms involved.

METHODS

Ob/ob, diet-induced obese (DIO) or PPARalpha knockout mice were administered a novel agonist that activates all PPARs to various degrees to determine the effect on body weight, body composition, food intake and energy expenditure. In addition, serum parameters including glucose, insulin, triglycerides and ketone bodies as well as tissue acylcarnitine were evaluated. The effect of the novel agonist on liver and skeletal muscle histopathology was also studied.

RESULTS

We report that simultaneous activation of all PPARs resulted in substantial weight loss in ob/ob and DIO mice. Consistent with known PPAR pharmacology, we observed that agonist treatment increased lipid oxidation, although appetite suppression was mainly responsible for the weight loss. Agonist-induced weight loss was completely absent in PPARalpha knockout mice suggesting that PPARalpha pharmacology was the major contributor to weight regulation in mice.

CONCLUSIONS

Our work provides evidence that simultaneous activation of PPARalpha, gamma and delta decreases body weight by regulating appetite. These effects of the pan agonist were completely absent in PPARalpha knockout mice, suggesting that PPARalpha pharmacology was the major contributor to weight loss.

2'-Chlorodeoxyadenosine Effectively Induces Complete Remission in Hairy Cell Leukaemia

Hairy cell leukaemia, previously known as leukaemic reticuloendotheliosis, is an indolent lymphoproliferative disorder of unknown etiology. It typically affects males, causes marked splenomegaly and moderate enlargement of the liver, whilst lymphadenopathy is inconspicuous. Pancytopenia is characteristic with unusually profound monocytopenia, variable reduction in platelets, and the presence in the peripheral blood and marrow of abnormal small lymphocytes having irregular cytoplasmic margins. Ultrastructure, combined with cytochemistry and flow cytometry, have refined diagnosis. A variant exists between this classical entity and B prolymphocytic leukaemia, where blastic transformation or massive lymph node enlargement are found, and this is of ominous significance. In all these patients with this entity conventional chemotherapy is ineffective and shortens survival. Our previous experience with splenectomy results in excellent clinical control for long periods of time, but without disease eradication. There followed a vogue for the use of interferon but this is limited by high cost and dose-dependent side-effects. Contemporary management centres on the purine analogues, where durable responses are possible with fludarabine and deoxycoformycin, but best with 2'chlorodeoxyadenosine (2-CDA). To document the efficacy of the latter agent, we analysed the outcome in seventeen consecutive patients treated over the last five years. Four were ineligible for analysis, although two had 2-CDA. The other thirteen, managed on a standard seven-day course of 0.1 mg/kg 2-CDA given as a continuous intravenous infusion, all responded promptly. Apart from transient leucopenia complications have been minimal, and oral co-trimoxazole prophylaxis for pneumocystis carinii was maintained during the first one year. In all thirteen there was a rapid return to normal of peripheral blood count and marrow on aspiration and trephine biopsy. Even in the longest follow-up clinical and haematologic remission has been maintained and no patients have required retreatment. One individual has relapsed in the marrow at two years. Despite the relative expense of the agent the excellent treatment outcome and patient acceptability, coupled with its safety, leads to the recommendation that in South Africa-as elsewhere in the world-this be regarded as the first line of treatment.

Hypoxaemia in patients with hyperleukocytosis: true or spurious, and clinical implications

It has been suggested that in asymptomatic patients with leukaemias and very high white blood cell counts, the apparent hypoxaemia found using routine blood gas analysis is spurious, the result of excessive O2 metabolism by leukocytes. Pulse oximetry has been suggested as a means of overcoming the shortcomings of blood gas analysis in the assessment of these patients. We present the findings of two patients with extremely high white cell counts, which show that the hypoxaemia found is in fact true hypoxaemia, even in asymptomatic patients, and that met-haemoglobinaemia may be at least in part responsible for the low PaO2. We also showed that pulse oximetry was completely unreliable in our patients due to the elevated met-haemoglobin levels. We recommend that all patients with markedly elevated white cell counts should undergo blood gas analysis with no delay between sampling and processing and that patients with low PaO2 should undergo urgent cytoreduction.