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Abstract Background Proper vector surveillance relies on the ability to identify species of interest accurately and efficiently, though this can be difficult in groups containing cryptic species. Culicoides Latreille is a genus of small biting flies responsible for the transmission of numerous pathogens to a multitude of vertebrates. Regarding pathogen transmission, the C. variipennis species complex is of particular interest in North America. Of the six species within this group, only C. sonorensis Wirth & Jones is a proven vector of bluetongue virus and epizootic hemorrhagic disease virus. Unfortunately, subtle morphological differences, cryptic species, and mitonuclear discordance make species identification in the C. variipennis complex challenging. Recently, single-nucleotide polymorphism (SNP) analysis enabled discrimination between the species of this group; however, this demanding approach is not practical for vector surveillance. Methods The aim of the current study was to develop a reliable and affordable way of distinguishing between the species within the C. variipennis complex, especially C. sonorensis. Twenty-five putative microsatellite markers were identified using the C. sonorensis genome and tested for amplification within five species of the C. variipennis complex. Machine learning was then used to determine which markers best explain the genetic differentiation between species. This led to the development of a subset of four and seven markers, which were also tested for species differentiation. Results A total of 21 microsatellite markers were successfully amplified in the species tested. Clustering analyses of all of these markers recovered the same species-level identification as the previous SNP data. Additionally, the subset of seven markers was equally capable of accurately distinguishing between the members of the C. variipennis complex as the 21 microsatellite markers. Finally, one microsatellite marker (C508) was found to be species-specific, only amplifying in the vector species C. sonorensis among the samples tested. Conclusions These microsatellites provide an affordable way to distinguish between the sibling species of the C. variipennis complex and could lead to a better understanding of the species dynamics within this group. Additionally, after further testing, marker C508 may allow for the identification of C. sonorensis with a single-tube assay, potentially providing a powerful new tool for vector surveillance in North America. Graphical Abstract

Social stress can contribute to the development of substance use disorders (SUDs) and increase the likelihood of relapse. Oxytocin (OT) is a potential pharmacotherapy that may buffer the effects of social stress on arousal and reward neurocircuitry. However, more research is needed to understand how OT moderates the brain’s response to social stress in SUDs. The present study examined the effect of intransasal OT (24 IU) versus placebo (PBO) on corticolimbic functional connectivity associated with acute social stress in individuals with cocaine use disorder (CUD; n = 67) and healthy controls (HC; n = 52). Psychophysiological interaction modeling used the left and right amygdala as seed regions with the left and right orbitofrontal and anterior cingulate cortex as a priori regions of interest. Moderators of the OT response included childhood trauma history and biological sex, which were examined in independent analyses. The main finding was that OT normalized corticolimbic connectivity (left amygdala-orbitofrontal and left amygdala-anterior cingulate) as a function of childhood trauma such that connectivity was different between trauma-present and trauma-absent groups on PBO, but not between trauma groups on OT. Effects of OT on corticolimbic connectivity were not different as a function of diagnosis (CUD vs HC) or sex. However, OT reduced subjective anxiety during social stress for CUD participants who reported childhood trauma compared to PBO and normalized craving response as a function of sex in CUD. The present findings add to some prior findings of normalizing effects of OT on corticolimbic circuitry in individuals with trauma histories and provide some initial support that OT can normalize subjective anxiety and craving in CUD.

A patient in Virginia, USA, who had previously undergone multiple kidney transplantations showed signs of Bordetella hinzii bacteremia and meningitis. This emerging pathogen has been increasingly identified as a clinically significant pathogen in immunosuppressed and, less frequently, immunocompetent patients. This patient was treated and recovered without further issue.

Abstract Facilitating coexistence between people and wildlife is a major conservation challenge in East Africa. Some conservation models aim to balance the needs of people and wildlife, but the effectiveness of these models is rarely assessed. Using a case‐study approach, we assessed the ecological performance of a pastoral area in northern Tanzania (Manyara Ranch) and established a long‐term wildlife population monitoring program (carried out intermittently from 2003 to 2008 and regularly from 2011 to 2019) embedded in a distance sampling framework. By comparing density estimates of the road transect‐based long‐term monitoring to estimates derived from systematically distributed transects, we found that the bias associated with nonrandom placement of transects was nonsignificant. Overall, cattle and sheep and goat reached the greatest densities and several wildlife species occurred at densities similar (zebra, wildebeest, waterbuck, Kirk's dik‐dik) or possibly even greater (giraffe, eland, lesser kudu, Grant's gazelle, Thomson's gazelle) than in adjacent national parks in the same ecosystem. Generalized linear mixed models suggested that most wildlife species (8 out of 14) reached greatest densities during the dry season, that wildlife population densities either remained constant or increased over the 17‐year period, and that herbivorous livestock species remained constant, while domestic dog population decreased over time. Cross‐species correlations did not provide evidence for interference competition between grazing or mixed livestock species and wildlife species but indicate possible negative relationships between domestic dog and warthog populations. Overall, wildlife and livestock populations in Manyara Ranch appear to coexist over the 17‐year span. Most likely, this is facilitated by existing connectivity to adjacent protected areas, effective anti‐poaching efforts, spatio‐temporal grazing restrictions, favorable environmental conditions of the ranch, and spatial heterogeneity of surface water and habitats. This long‐term case study illustrates the potential of rangelands to simultaneously support wildlife conservation and human livelihood goals if livestock grazing is restricted in space, time, and numbers.

Information regarding Coronavirus disease 2019 in the transplant population is lacking. Recently it has been suggested that cycle threshold values obtained on polymerase chain reaction tests may serve as a marker of disease severity with lower values (i.e., higher viral load) being associated with higher mortality. This study was done to assess the impact of remdesivir use on the time to a negative COVID-19 PCR as well as the degree of change between two Ct’s based on treatment. A total of 30 kidney transplant patients with a new diagnosis of COVID-19 were assessed. Serial PCR results were followed from the time of diagnosis then every 2–4 weeks until negative. In patients who received remdesivir immediately after COVID-19 confirmation compared to no remdesivir, time to negative PCR was not statistically different with a median duration of 57 days in both groups (p = 0.369). The change in the Ct between the first and the second PCR test was also not statistically different between groups with a median change of 18.4 cycles in the remdesivir group and 15.7 cycles without remdesivir (p = 0.516). The results of this small single-center analysis suggest that remdesivir may not be beneficial in shortening time to a negative COVID-19 PCR.

Cocaine use disorder (CUD) is a major public health concern with devastating social, economic, and mental health implications. A better understanding of the underlying neurobiology and phenotypic variations in individuals with CUD is necessary for the development of effective and targeted treatments. In this study, 39 women and 54 men with CUD completed a 6-min resting-state functional magnetic resonance imaging scan after intranasal oxytocin (OXY) or placebo administration. Graph-theory network analysis was used to quantify functional connectivity changes caused by OXY in striatum, anterior cingulate cortex (ACC), insula, and amygdala nodes of interest. OXY increased connectivity in the right ACC and left amygdala in males, whereas OXY increased connectivity in the right ACC and right accumbens in females. Machine learning was then used to associate treatment response (placebo minus OXY) in nodes of interest with years of cocaine use and severity of childhood trauma separately for males and females. Childhood trauma and years of cocaine use were associated with OXY-induced changes in ACC connectivity for both men and women, but connectivity changes in the amygdala were associated with years of cocaine use in men and connectivity changes in the right insula were associated with years of cocaine use in women. These findings suggest that salience network nodes (ACC and insula) are potential OXY treatment targets in CUD, with the amygdala as a treatment target for men and the accumbens as a treatment target for women.