A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa

A multigene phylogenetic assessment of North American species of Mallocybe is presented based on analyses of rpb1, rpb2, ITS, and 28S rDNA nucleotide data. This framework enables a systematic revision of the genus for 16 eastern North American species and captures taxonomic and phylogenetic diversity in a global context. A grade of two unusual and poorly known North American species stems from the most recent common ancestor of the genus that gives rise to three core subgroups named here as clades Unicolores, Nothosperma, and Mallocybe. The grade of taxa includes the poorly known Lepista praevillosa from Florida and a new species from the southern Appalachians, M. montana, both of which appear to be narrow-range endemics. Clade Nothosperma is characterized by Australian and New Zealand species, whereas clade Unicolores is composed of six species from eastern North America and East Asia. Clade Mallocybe is dominated by numerous north temperate taxa and constitutes the sister group to clade Nothosperma. These major clades are distinguished by a combination of phylogeny, morphology, geographic distribution, and ecology. In addition, four North American species are described as new: M. leucothrix, M. luteobasis, M. montana, and M. tomentella. Several names originating in North America, long ignored or misunderstood in the literature, are revitalized and established by type comparisons and modern reference material collected from or near type localities. In addition, 11 species were subjected to mass spectrometry muscarine assays, none of which contained detectable amounts of muscarine except for two: M. sabulosa and M. praevillosa. This confirms a diffuse phylogenetic distribution of muscarine within the genus. Taxonomic descriptions are presented for 16 species, several synonymies proposed, and four new combinations made. A key to species of eastern North American Mallocybe is presented, along with illustrations of important diagnostic features. Citation: Matheny PB, Kudzma LV, Graddy MG, Mardini SM, Noffsinger CR, Swenie RA, Walker NC, Campagna SR, Halling R, Lebeuf R, Kuo M, Lewis DP, Smith ME, Tabassum M, Trudell SA, Vauras J (2023). A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa. Fungal Systematics and Evolution 12: 153-201. doi: 10.3114/fuse.2023.12.09.

Efficacy of dopamine, epinephrine and blood transfusion for treatment of fluid refractory shock in children with severe acute malnutrition or severe underweight and cholera or other dehydrating diarrhoeas: protocol for a randomised controlled clinical trial

INTRODUCTION

Diarrhoea is one of the leading causes of under-5 childhood mortality and accounts for 8% of 5.4 million global under-5 deaths. In severely malnourished children, diarrhoea progresses to shock, where the risk of mortality is even higher. At icddr,b Dhaka Hospital, the fatality rate is as high as 69% in children with severe malnutrition and fluid refractory septic shock. To date, no study has evaluated systematically the effects of inotrope or vasopressor or blood transfusion in children with dehydrating diarrhoea (eg, in cholera) and severe acute malnutrition (SAM) or severe underweight who are in shock and unresponsive to WHO-recommended fluid therapy. To reduce the mortality of severely malnourished children presenting with diarrhoea and fluid refractory shock, we aim to compare the efficacy of blood transfusion, dopamine and epinephrine in fluid refractory shock in children who do not respond to WHO-recommended fluid resuscitation.

METHODS AND ANALYSIS

In this randomised, three-arm, controlled, non-masked clinical trial in children 1-59 months old with SAM or severe underweight and fluid refractory shock, we will compare the efficacy of dopamine or epinephrine administration versus blood transfusion in children who failed to respond to WHO-recommended fluid resuscitation. The primary outcome variable is the case fatality rate. The effect of the intervention will be assessed by performing an intention-to-treat analysis. Recruitment and data collection began in July 2021 and are now ongoing. Results are expected by May 2023.

ETHICS AND DISSEMINATION

This study has been approved by the icddr,b Institutional Review Board. We adhere to the 'Declaration of Helsinki' (2000), guidelines for Good Clinical Practice. Before enrolment, we collect signed informed consent from the parents or caregivers of the children. We will publish the results in a peer-reviewed journal and will arrange a dissemination seminar.

TRIAL REGISTRATION NUMBER

NCT04750070.

Vitamin D supplementation among Bangladeshi children under-five years of age hospitalised for severe pneumonia: A randomised placebo controlled trial

INTRODUCTION

Vitamin D is important for its immunomodulatory role and there is an independent association between vitamin D deficiency and pneumonia. We assessed the effect of vitamin D supplementation on the outcome in children hospitalized for severe pneumonia.

METHODS

This was a randomised, double blinded, placebo-controlled clinical trial in children aged >2-59 months with severe pneumonia attending Dhaka Hospital, icddr,b. Children received age-specific megadose of vitamin D3 (20,000IU: <6 months, 50,000 IU: 6-12 months, 100,000 IU:13-59 months) or placebo on first day and 10,000 IU as maintenance dose for next 4 days or until discharge (if discharged earlier) along with standard therapy. This trial is registered at ClinicalTrials.gov, number NCT02185196.

FINDINGS

We enrolled 100 children in placebo group and 97 in vitamin D group. On admission, 50 (52%) and 49 (49%) of children in vitamin D and placebo groups, respectively were vitamin D deficient. Among children with a sufficient serum vitamin D level on admission, a lower trend for duration of resolution of severe pneumonia in hours [72(IQR:44-96)vs. 88(IQR:48-132);p = 0.07] and duration of hospital stay in days [4(IQR:3-5)vs.5(IQR:4-7);P = 0.09] was observed in vitamin D group compared to placebo. No beneficial effect was observed in vitamin D deficient group or irrespective of vitamin D status.

CONCLUSION

Age-specific mega dose of vitamin D followed by a maintenance dose shown to have no statistical difference between the two intervention groups, however there was a trend of reduction of time to recovery from pneumonia and overall duration of hospital stay in under-five children with a sufficient serum vitamin D level on hospital admission.